Acute impairment of regional myocardial glucose uptake in the apical ballooning (takotsubo) syndrome.

PubMed

Bybee, Kevin A; Murphy, Joseph; Prasad, Abhiram; Wright, R Scott; Lerman, Amir; Rihal, Charanjit S; Chareonthaitawee, Panithaya

2006-01-01

Apical ballooning syndrome (ABS) is a poorly understood clinical entity characterized by acute, transient systolic dysfunction of the left ventricular (LV) apex in the absence of epicardial coronary artery disease and commonly associated with acute emotional stress. We report abnormal regional myocardial perfusion and glucose uptake in 4 consecutive ABS patients studied using positron emission tomography with 13N-ammonia and 18F-fluorodeoxyglucose within 72 hours of presentation with ABS. All patients were postmenopausal females, 3 of whom had a major recent life stress event. Coronary angiography revealed no or minimal obstructive epicardial coronary artery disease. All patients exhibited reduced glucose uptake in the mid-LV and apical myocardial segments, which was out of proportion to perfusion abnormalities in half of the cases. In all 4 patients, affected regions subsequently recovered regional LV systolic function within 6 weeks.

Nicorandil improves myocardial function by regulating plasma nitric oxide and endothelin-1 in coronary slow flow

PubMed Central

Chen, Xiuhua; Li, Shan; Huo, Xuezhen; Fu, Xiuxiu; Dong, Xiaonan

2015-01-01

Background Coronary slow flow (CSF) is a special coronary microvascular disorder. The pathogenesis and effective therapeutics of CSF remain unclear. This study aimed to evaluate the global and regional functions of the left ventricle (LV) and investigate the efficacy of nicorandil in patients with CSF. Patients and methods Thirty-six patients with CSF in the left anterior descending (LAD) branch and 20 patients with normal coronary arteries were included. Global and regional functions of the LV supplied by LAD were measured using conventional Doppler echocardiography and two-dimensional speckle tracking echocardiography, respectively, within 24 h after coronary angiography. Concentrations of plasma nitric oxide (NO) and endothelin-1 (ET-1) were detected using colorimetry and radioimmunoassay, respectively. The function of the LV and the levels of NO and ET-1 were also investigated before and 90 days after treatment with 15 mg/day of nicorandil. Results Compared with the control group, the early diastolic peak velocity (E), E/A ratio, and plasma NO levels were lower, whereas the late diastolic peak flow velocity (A) and plasma ET-1 levels were significantly higher in the CSF group (P<0.05). The longitudinal strain rate peak of the LV was reduced significantly in CSF patients (P<0.001). After treatment, 75% (27/36) of CSF patients were free of chest pain. The values of E peak, E/A ratio, longitudinal strain rate peak, and plasma NO level were increased (P<0.001), whereas the ET-1 level was decreased in CSF patients (P<0.001). Conclusion Nicorandil may improve chest pain symptoms and the impaired function of the LV, possibly by increasing plasma NO and reducing ET-1 in CSF. PMID:25325437

Percutaneous closure of patent ductus arteriosus in children: Immediate and short-term changes in left ventricular systolic and diastolic function.

PubMed

Gupta, Saurabh Kumar; Krishnamoorthy, Km; Tharakan, Jaganmohan A; Sivasankaran, S; Sanjay, G; Bijulal, S; Anees, T

2011-07-01

To evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) systolic and diastolic function in children. Limited studies are available on alteration in LV hemodynamics, especially diastolic function, after PDA closure. Thirty-two consecutive children with isolated PDA treated by trans-catheter closure were studied. The LV systolic and diastolic function were assessed by two-dimensional (2D) echocardiography and tissue Doppler imaging 1 day before the PDA closure, on day 1, and on follow-up. At baseline, none of the patients had LV systolic dysfunction. On day 1 post-PDA closure, 8 (25%) children developed LV systolic dysfunction. The baseline LV ejection fraction (LVEF), LV end-systolic dimension (LVESD), and PDA diastolic gradient predicted the post-closure LVEF. Patients who developed post-closure LV systolic dysfunction had poorer LV diastolic function than those who did not. LV diastolic properties improved after PDA closure; however, the improvement in LV diastolic properties lagged behind the improvement in the LV systolic function. All children were asymptomatic and had normal LVEF on follow up of >3 months. Percutaneous closure of PDA is associated with the reversible LV systolic dysfunction. Improvement in the LV diastolic function lags behind that in the LV systolic function.

Identification of a C-type lectin with antiviral and antibacterial activity from pacific white shrimp Litopenaeus vannamei.

PubMed

Li, Ming; Li, Chaozheng; Ma, Chunxia; Li, Haoyang; Zuo, Hongliang; Weng, Shaoping; Chen, Xiaohan; Zeng, Digang; He, Jianguo; Xu, Xiaopeng

2014-10-01

C-type lectins (CTLs) play crucial roles in innate immune responses in invertebrates by recognizing and eliminating microinvaders. In this study, a CTL from pacific white shrimp Litopenaeus vannamei (LvCTL3) was identified. LvCTL3 contains a single C-type lectin-like domain (CTLD), which shows similarities to those of other shrimp CTLs and has a mutated 'EPD' motif in Ca(2+)-binding site 2. LvCTL3 mRNA can be detected in all tested tissues and expression of LvCTL3 in gills was up-regulated after Lipopolysaccharides, poly (I:C), Vibrio parahaemolyticus and white spot syndrome virus (WSSV) challenges, suggesting activation responses of LvCTL3 to bacterial, virus and immune stimulant challenges. The 5'flanking regulatory region of LvCTL3 was cloned and we identified a NF-κB binding motif in the LvCTL3 promoter region. Dual-luciferase reporter assays indicated that over-expression of L. vannamei dorsal can dramatically up regulate the promoter activity of LvCTL3, suggesting that LvCTL3 expression could be regulated through NF-κB signaling pathway. As far as we know, this is the first report on signaling pathway involve in shrimp CTLs expression. The recombinant LvCTL3 protein was expressed in Escherichia coli and purified by Ni-affinity chromatography. The purified LvCTL3 can agglutinate Gram-negative microbe Vibrio alginolyticus and V. parahaemolyticus and Gram-positive bacteria Bacillus subtilis in the presence of calcium ions, but cannot agglutinate Gram-positive bacteria Streptococcus agalactiae. The agglutination activity of LvCTL3 was abolished when Ca(2+) was chelated with EDTA, suggesting the function of LvCTL3 is Ca(2+)-dependent. In vivo challenge experiments showed that the recombinant LvCTL3 protein can significantly reduce the mortalities of V. parahemolyticus and WSSV infection, indicating LvCTL3 might play significant roles in shrimp innate immunity defense against bacterial and viral infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Computer-based assessment of left ventricular regional ejection fraction in patients after myocardial infarction

NASA Astrophysics Data System (ADS)

Teo, S.-K.; Su, Y.; Tan, R. S.; Zhong, L.

2014-03-01

After myocardial infarction (MI), the left ventricle (LV) undergoes progressive remodeling which adversely affects heart function and may lead to development of heart failure. There is an escalating need to accurately depict the LV remodeling process for disease surveillance and monitoring of therapeutic efficacy. Current practice of using ejection fraction to quantitate LV function is less than ideal as it obscures regional variation and anomaly. Therefore, we sought to (i) develop a quantitative method to assess LV regional ejection fraction (REF) using a 16-segment method, and (ii) evaluate the effectiveness of REF in discriminating 10 patients 1-3 months after MI and 9 normal control (sex- and agematched) based on cardiac magnetic resonance (CMR) imaging. Late gadolinium enhancement (LGE) CMR scans were also acquired for the MI patients to assess scar extent. We observed that the REF at the basal, mid-cavity and apical regions for the patient group is significantly lower as compared to the control group (P < 0.001 using a 2-tail student t-test). In addition, we correlated the patient REF over these regions with their corresponding LGE score in terms of 4 categories - High LGE, Low LGE, Border and Remote. We observed that the median REF decreases with increasing severity of infarction. The results suggest that REF could potentially be used as a discriminator for MI and employed to measure myocardium homogeneity with respect to degree of infarction. The computational performance per data sample took approximately 25 sec, which demonstrates its clinical potential as a real-time cardiac assessment tool.

Left ventricular strain distribution in healthy dogs and in dogs with tachycardia-induced dilated cardiomyopathy

PubMed Central

2013-01-01

Background Recently, left ventricular (LV) strain distribution pattern has been assessed in several cardiac disease states. Tachycardia-induced cardiomyopathy (TIC) is an animal model of non-ischemic cardiomyopathy well characterized in terms of global LV dysfunction but with poor understanding of regional variability in LV function. We hypothesized that TIC induces specific changes in LV strain distribution pattern. Methods Twenty five adult mongrel conscious dogs were trained to lie down calmly for echocardiography. In seven selected dogs, we implanted pacing system for TIC induction under general anesthesia. We measured LV geometry and function, strains, and torsion before and after the development of TIC in awake non-sedated state. Results In 25 healthy dogs, all three types of normal strain significantly increased from base to apex (p <0.05), while a definite and recognizable twist could be measured due to presence of shear strain. In 7 dogs with TIC, marked changes in LV mechanics occurred throughout the cardiac cycle, resulting in decrease of strain (p <0.001), twist (p <0.05), and negative peak twist rate (p <0.05). Interestingly, the relative decrease of strain due to TIC was more pronounced in the apex (p < 0.001), with the radial strain decreasing the most (p < 0.05). Conclusion TIC is accompanied by decreased systolic LV strain and twist deformation, as well as loss of early diastolic recoil. In addition, the decrease of strain was more profound in the apex. This “reverse” distribution of LV strain may help us understand LV dysfunction in the presence of nonischemic etiology. PMID:24304622

Left ventricular strain distribution in healthy dogs and in dogs with tachycardia-induced dilated cardiomyopathy.

PubMed

Kusunose, Kenya; Zhang, Youhua; Mazgalev, Todor N; Thomas, James D; Popović, Zoran B

2013-12-05

Recently, left ventricular (LV) strain distribution pattern has been assessed in several cardiac disease states. Tachycardia-induced cardiomyopathy (TIC) is an animal model of non-ischemic cardiomyopathy well characterized in terms of global LV dysfunction but with poor understanding of regional variability in LV function. We hypothesized that TIC induces specific changes in LV strain distribution pattern. Twenty five adult mongrel conscious dogs were trained to lie down calmly for echocardiography. In seven selected dogs, we implanted pacing system for TIC induction under general anesthesia. We measured LV geometry and function, strains, and torsion before and after the development of TIC in awake non-sedated state. In 25 healthy dogs, all three types of normal strain significantly increased from base to apex (p <0.05), while a definite and recognizable twist could be measured due to presence of shear strain. In 7 dogs with TIC, marked changes in LV mechanics occurred throughout the cardiac cycle, resulting in decrease of strain (p <0.001), twist (p <0.05), and negative peak twist rate (p <0.05). Interestingly, the relative decrease of strain due to TIC was more pronounced in the apex (p < 0.001), with the radial strain decreasing the most (p < 0.05). TIC is accompanied by decreased systolic LV strain and twist deformation, as well as loss of early diastolic recoil. In addition, the decrease of strain was more profound in the apex. This "reverse" distribution of LV strain may help us understand LV dysfunction in the presence of nonischemic etiology.

Relation between exercise central haemodynamic response and resting cardiac structure and function in young healthy men.

PubMed

Babcock, Matthew C; Lefferts, Wesley K; Heffernan, Kevin S

2017-07-01

Left ventricular (LV) structure and function are predictors of cardiovascular (CV) morbidity and mortality and are related to resting peripheral haemodynamic load in older adults. The central haemodynamic response to exercise may reveal associations with LV structure and function not detected by traditional peripheral (brachial) measures in a younger population. To examine correlations between acute exercise-induced changes in central artery stiffness and wave reflections and measures of resting LV structure and function. Sixteen healthy men (age 26 ± 6 year; BMI 25·3 ± 2·7 kg m -2 ) had measures of central haemodynamic load measured before/after a 30-s Wingate anaerobic test (WAT). Common carotid artery stiffness and reflected wave intensity were assessed via wave intensity analysis as a regional pulse wave velocity (PWV) and negative area (NA), respectively. Resting LV structure (LV mass) and function [midwall fractional shortening (mFS)] were assessed using M-mode echocardiography in the parasternal short-axis view. There was a significant association between mFS and WAT-mediated change in carotid systolic BP (r = -0·57, P = 0·011), logNA (r = -0·58, P = 0·009) and PWV (r = -0·44, P = 0·045). There were no significant associations between resting mFS and changes in brachial systolic BP (r = -0·26, P>0·05). There were no associations between resting LV mass and changes in any haemodynamic variable (P>0·05). Exercise-induced increases in central haemodynamic load reveal associations with lower resting LV function in young healthy men undetected by traditional peripheral haemodynamics. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Influence of pacing site characteristics on response to cardiac resynchronization therapy.

PubMed

Wong, Jorge A; Yee, Raymond; Stirrat, John; Scholl, David; Krahn, Andrew D; Gula, Lorne J; Skanes, Allan C; Leong-Sit, Peter; Klein, George J; McCarty, David; Fine, Nowell; Goela, Aashish; Islam, Ali; Thompson, Terry; Drangova, Maria; White, James A

2013-07-01

Transmural scar occupying left ventricular (LV) pacing regions has been associated with reduced response to cardiac resynchronization therapy (CRT). However, spatial influences of lead tip delivery relative to scar at both pacing sites remain poorly explored. This study evaluated scar distribution relative to LV and right ventricular (RV) lead tip placement through coregistration of late gadolinium enhancement MRI and cardiac computed tomographic (CT) findings. Influences on CRT response were assessed by serial echocardiography. Sixty patients receiving CRT underwent preimplant late gadolinium enhancement MRI, postimplant cardiac CT, and serial echocardiography. Blinded segmental evaluations of mechanical delay, percentage scar burden, and lead tip location were performed. Response to CRT was defined as a reduction in LV end-systolic volume ≥15% at 6 months. The mean age and LV ejection fraction were 64±9 years and 25±7%, respectively. Mean scar volume was higher among CRT nonresponders for both the LV (23±23% versus 8±14% [P=0.01]) and RV pacing regions (40±32% versus 24±30% [P=0.04]). Significant pacing region scar was identified in 13% of LV pacing regions and 37% of RV pacing regions. Absence of scar in both regions was associated with an 81% response rate compared with 55%, 25%, and 0%, respectively, when the RV, LV, or both pacing regions contained scar. LV pacing region dyssynchrony was not predictive of response. Myocardial scar occupying the LV pacing region is associated with nonresponse to CRT. Scar occupying the RV pacing region is encountered at higher frequency and seems to provide a more intermediate influence on CRT response.

Alterations in left ventricular curvature and principal strains in dilated cardiomyopathy with functional mitral regurgitation.

PubMed

Tibayan, Frederick A; Lai, David T M; Timek, Tomasz A; Dagum, Paul; Liang, David; Zasio, Mary K; Daughters, George T; Miller, D Craig; Ingels, Neil B

2003-05-01

Functional mitral regurgitation (FMR) is increasingly recognized as a left ventricular (LV) disease. Dilated cardiomyopathy (DCM) is commonly accompanied by FMR and reduction of LV torsion. Therapeutic targets for DCM include LV size reduction, altered LV shape, elimination of MR, and increasing LV torsion. It was hypothesized that, in addition to increasing LV size, DCM with FMR would alter normal LV shape and reduce and alter the direction of principal strains across the LV wall. This hypothesis was tested by measuring changes in epicardial and endocardial 2-D principal strains and regional radii of curvature accompanying tachycardia-induced cardiomyopathy in ovine hearts. Radio-opaque marker arrays were implanted into the left ventricle of eight sheep, including one subepicardial triangle and one subendocardial triangle in the anterior wall of the left ventricle. At one week postoperatively, biplane videofluoroscopy was used to determine marker dynamics. Rapid ventricular pacing was then instituted until FMR and signs of heart failure developed, and fluoroscopy was repeated. Circumferential LV radii of curvature were determined from marker triplets. DCM changed the normal epicardial oval LV cross-section to a more circular configuration. The endocardium maintained its normal circular shape as the left ventricle dilated. Deformations of the triangles from end-diastole to end-systole were determined, and the magnitude and direction of 2-D principal strains calculated. DCM was associated with decreased magnitude of both epicardial (-0.095 +/- 0.055 versus -0.040 +/- 0.032, p = 0.006) and endocardial (-0.117 +/- 0.047 versus -0.073 +/- 0.037, p = 0.023) principal strains. DCM reduced the angle of epicardial but not endocardial principal strain. DCM with FMR is associated with LV dilation, circularization of the normally oval equatorial circumferential LV epicardium, transmural reduction in principal strain, and decrease in angle of principal epicardial strain. These changes contribute to a reduction in the net torsional moment and may guide the development of reverse remodeling procedures for the dilated, failing ventricle with FMR.

Quantification of regional myocardial blood flow estimation with three-dimensional dynamic rubidium-82 PET and modified spillover correction model.

PubMed

Katoh, Chietsugu; Yoshinaga, Keiichiro; Klein, Ran; Kasai, Katsuhiko; Tomiyama, Yuuki; Manabe, Osamu; Naya, Masanao; Sakakibara, Mamoru; Tsutsui, Hiroyuki; deKemp, Robert A; Tamaki, Nagara

2012-08-01

Myocardial blood flow (MBF) estimation with (82)Rubidium ((82)Rb) positron emission tomography (PET) is technically difficult because of the high spillover between regions of interest, especially due to the long positron range. We sought to develop a new algorithm to reduce the spillover in image-derived blood activity curves, using non-uniform weighted least-squares fitting. Fourteen volunteers underwent imaging with both 3-dimensional (3D) (82)Rb and (15)O-water PET at rest and during pharmacological stress. Whole left ventricular (LV) (82)Rb MBF was estimated using a one-compartment model, including a myocardium-to-blood spillover correction to estimate the corresponding blood input function Ca(t)(whole). Regional K1 values were calculated using this uniform global input function, which simplifies equations and enables robust estimation of MBF. To assess the robustness of the modified algorithm, inter-operator repeatability of 3D (82)Rb MBF was compared with a previously established method. Whole LV correlation of (82)Rb MBF with (15)O-water MBF was better (P < .01) with the modified spillover correction method (r = 0.92 vs r = 0.60). The modified method also yielded significantly improved inter-operator repeatability of regional MBF quantification (r = 0.89) versus the established method (r = 0.82) (P < .01). A uniform global input function can suppress LV spillover into the image-derived blood input function, resulting in improved precision for MBF quantification with 3D (82)Rb PET.

Intravenously Delivered Mesenchymal Stem Cells: Systemic Anti-Inflammatory Effects Improve Left Ventricular Dysfunction in Acute Myocardial Infarction and Ischemic Cardiomyopathy.

PubMed

Luger, Dror; Lipinski, Michael J; Westman, Peter C; Glover, David K; Dimastromatteo, Julien; Frias, Juan C; Albelda, M Teresa; Sikora, Sergey; Kharazi, Alex; Vertelov, Grigory; Waksman, Ron; Epstein, Stephen E

2017-05-12

Virtually all mesenchymal stem cell (MSC) studies assume that therapeutic effects accrue from local myocardial effects of engrafted MSCs. Because few intravenously administered MSCs engraft in the myocardium, studies have mainly utilized direct myocardial delivery. We adopted a different paradigm. To test whether intravenously administered MSCs reduce left ventricular (LV) dysfunction both post-acute myocardial infarction and in ischemic cardiomyopathy and that these effects are caused, at least partly, by systemic anti-inflammatory activities. Mice underwent 45 minutes of left anterior descending artery occlusion. Human MSCs, grown chronically at 5% O 2 , were administered intravenously. LV function was assessed by serial echocardiography, 2,3,5-triphenyltetrazolium chloride staining determined infarct size, and fluorescence-activated cell sorting assessed cell composition. Fluorescent and radiolabeled MSCs (1×10 6 ) were injected 24 hours post-myocardial infarction and homed to regions of myocardial injury; however, the myocardium contained only a small proportion of total MSCs. Mice received 2×10 6 MSCs or saline intravenously 24 hours post-myocardial infarction (n=16 per group). At day 21, we harvested blood and spleens for fluorescence-activated cell sorting and hearts for 2,3,5-triphenyltetrazolium chloride staining. Adverse LV remodeling and deteriorating LV ejection fraction occurred in control mice with large infarcts (≥25% LV). Intravenous MSCs eliminated the progressive deterioration in LV end-diastolic volume and LV end-systolic volume. MSCs significantly decreased natural killer cells in the heart and spleen and neutrophils in the heart. Specific natural killer cell depletion 24 hours pre-acute myocardial infarction significantly improved infarct size, LV ejection fraction, and adverse LV remodeling, changes associated with decreased neutrophils in the heart. In an ischemic cardiomyopathy model, mice 4 weeks post-myocardial infarction were randomized to tail-vein injection of 2×10 6 MSCs, with injection repeated at week 3 (n=16) versus PBS control (n=16). MSCs significantly increased LV ejection fraction and decreased LV end-systolic volume. Intravenously administered MSCs for acute myocardial infarction attenuate the progressive deterioration in LV function and adverse remodeling in mice with large infarcts, and in ischemic cardiomyopathy, they improve LV function, effects apparently modulated in part by systemic anti-inflammatory activities. © 2017 American Heart Association, Inc.

Impact of Hypertension on Ventricular-Arterial Coupling and Regional Myocardial Work at Rest and during Isometric Exercise

PubMed Central

Kuznetsova, Tatiana; D’hooge, Jan; Kloch-Badelek, Malgorzata; Sakiewicz, Wojciech; Thijs, Lutgarde; Staessen, Jan A.

2013-01-01

Background To understand better the mechanism of left ventricular (LV) remodeling related to hypertension, it is important to evaluate LV function in relation to the changes in loading conditions. The aim of this study was to investigate changes in conventional ventricular-arterial coupling indexes, LV strain, and a new index reflecting regional myocardial work assessed noninvasively at rest and during isometric exercise in a random sample including participants with normal blood pressure and those with hypertension. Methods A total of 148 participants (53.4% women; mean age, 52.0 years; 39.2% with hypertension) underwent simultaneous echocardiographic and arterial data acquisition at rest and during increased afterload (handgrip exercise). End-systolic pressure was determined from the carotid pulse wave. Arterial elastance (Ea) and LV elastance (Ees) were calculated as end-systolic pressure/stroke volume and end-systolic pressure/end-systolic volume. Doppler tissue imaging and two-dimensional speckle tracking were used to derive LV longitudinal strain. Regional myocardial work (ejection work density [EWD]) was the area of the pressure-strain loop during ejection. Results At rest, with adjustments applied, Ees (3.06 vs 3.71 mmHg/mL,P = .0003), Ea/Ees (0.54 vs 0.47,P=.002) and EWD (670 vs 802 Pa/m2, P = .0001) differed significantly between participants with normal blood pressure and those with hypertension. During handgrip exercise, Ea and Ea/Ees significantly increased (P < .0001) in both groups. Doppler tissue imaging and two-dimensional LV strain decreased in participants with hypertension (P ≤ .008). Only in subjects with normal blood pressure EWD significantly increased (+14.7%, P = .0009). Conclusions Although patients with hypertension compared with those with normal blood pressure have increased LV systolic stiffness and regional myocardial work to match arterial load at rest, they might have diminished cardiac reserve to increase myocardial performance, as estimated by EWD during isometric exercise. PMID:22622108

Heart deformation analysis for automated quantification of cardiac function and regional myocardial motion patterns: A proof of concept study in patients with cardiomyopathy and healthy subjects.

PubMed

Lin, Kai; Collins, Jeremy D; Chowdhary, Varun; Markl, Michael; Carr, James C

2016-10-01

To test the performance of HDA in characterizing left ventricular (LV) function and regional myocardial motion patterns in the context of cardiomyopathy based on cine cardiovascular magnetic resonance (CMR). Following the approval of the institutional review board (IRB), standard cine images of 45 subjects, including 15 healthy volunteers, 15 patients with hypertrophic cardiomyopathy (HCM) and 15 patients with dilated cardiomyopathy (DCM) were retrospectively analyzed using HDA. The variations of LV ejection fraction (LVEF), LV mass (LVM), and regional myocardial motion indices, including radial (Drr), circumferential (Dcc) displacement, radial (Vrr) and circumferential (Vcc) velocity, radial (Err), circumferential (Ecc) and shear (Ess) strain and radial (SRr) and circumferential (SRc) strain rate, were calculated and compared among subject groups. Inter-study reproducibility of HDA-derived myocardial motion indices were tested on 15 volunteers by using intra-class correlation coefficient (ICC) and coefficient of variation (CoV). HDA identified significant differences in cardiac function and motion indices between subject groups. DCM patients had significantly lower LVEF (33.5±9.65%), LVM (105.88±21.93g), peak Drr (0.29±0.11cm), Vrr-sys (2.14±0.72cm/s), Err (0.17±0.08), Ecc (-0.08±0.03), SRr-sys (0.91±0.44s(-1)) and SRc-sys (-0.64±0.27s(-1)) compared to the other two groups. HCM patients demonstrated increased LVM (171.69±34.19) and lower peak Vcc-dia (0.78±0.30cm/s) than other subjects. Good inter-study reproducibility was found for all HDA-derived myocardial indices in healthy volunteers (ICC=0.664-0.942, CoV=15.1%-37.1%). Without the need for operator interaction, HDA is a reproducible method for the automated characterization of global and regional LV function in the context of cardiomyopathy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Using the laws of thermodynamics to understand how matrix metalloproteinases coordinate the myocardial response to injury.

PubMed

Iyer, Rugmani Padmanabhan; Jung, Mira; Lindsey, Merry L

Following myocardial infarction (MI), the left ventricle (LV) undergoes a series of molecular, cellular, and functional alterations that are both part of the wound healing response to form a scar in the infarct region and the consequence of that response. Using the laws of thermodynamics as an analogy, we present here three laws for categorizing the post-MI LV remodeling process. The first law is that the LV will attempt to maintain equilibrium and compensate as a way to maximize function, the second law is that remodeling is progressive and unidirectional, and the third law is that the final goal is (ideally, but not always achievable) a stable, equilibrated scar. This comparison helps to define the boundaries of the system, whether it be the infarct zone, the LV, the heart, or the entire body. This review provides an overview for those not directly in the field and establishes a framework to help prioritize future research directions.

Using the laws of thermodynamics to understand how matrix metalloproteinases coordinate the myocardial response to injury

PubMed Central

Iyer, Rugmani Padmanabhan; Jung, Mira; Lindsey, Merry L

2016-01-01

Following myocardial infarction (MI), the left ventricle (LV) undergoes a series of molecular, cellular, and functional alterations that are both part of the wound healing response to form a scar in the infarct region and the consequence of that response. Using the laws of thermodynamics as an analogy, we present here three laws for categorizing the post-MI LV remodeling process. The first law is that the LV will attempt to maintain equilibrium and compensate as a way to maximize function, the second law is that remodeling is progressive and unidirectional, and the third law is that the final goal is (ideally, but not always achievable) a stable, equilibrated scar. This comparison helps to define the boundaries of the system, whether it be the infarct zone, the LV, the heart, or the entire body. This review provides an overview for those not directly in the field and establishes a framework to help prioritize future research directions. PMID:27376092

Right Ventricular Strain, Torsion, and Dyssynchrony in Healthy Subjects using 3D Spiral Cine DENSE Magnetic Resonance Imaging

PubMed Central

Suever, Jonathan D; Wehner, Gregory J; Jing, Linyuan; Powell, David K; Hamlet, Sean M; Grabau, Jonathan D; Mojsejenko, Dimitri; Andres, Kristin N; Haggerty, Christopher M; Fornwalt, Brandon K

2017-01-01

Mechanics of the left ventricle (LV) are important indicators of cardiac function. The role of right ventricular (RV) mechanics is largely unknown due to the technical limitations of imaging its thin wall and complex geometry and motion. By combining 3D Displacement Encoding with Stimulated Echoes (DENSE) with a post-processing pipeline that includes a local coordinate system, it is possible to quantify RV strain, torsion, and synchrony. In this study, we sought to characterize RV mechanics in 50 healthy individuals and compare these values to their LV counterparts. For each cardiac frame, 3D displacements were fit to continuous and differentiable radial basis functions, allowing for the computation of the 3D Cartesian Lagrangian strain tensor at any myocardial point. The geometry of the RV was extracted via a surface fit to manually delineated endocardial contours. Throughout the RV, a local coordinate system was used to transform from a Cartesian strain tensor to a polar strain tensor. It was then possible to compute peak RV torsion as well as peak longitudinal and circumferential strain. A comparable analysis was performed for the LV. Dyssynchrony was computed from the standard deviation of regional activation times. Global circumferential strain was comparable between the RV and LV (−18.0% for both) while longitudinal strain was greater in the RV (−18.1% vs. −15.7%). RV torsion was comparable to LV torsion (6.2 vs. 7.1 degrees, respectively). Regional activation times indicated that the RV contracted later but more synchronously than the LV. 3D spiral cine DENSE combined with a post–processing pipeline that includes a local coordinate system can resolve both the complex geometry and 3D motion of the RV. PMID:28055859

Regional quantification of myocardial mechanics in rat using 3D cine DENSE cardiovascular magnetic resonance.

PubMed

Zhang, Xiaoyan; Liu, Zhan-Qiu; Singh, Dara; Wehner, Gregory J; Powell, David K; Campbell, Kenneth S; Fornwalt, Brandon K; Wenk, Jonathan F

2017-08-01

Rat models have assumed an increasingly important role in cardiac research. However, a detailed profile of regional cardiac mechanics, such as strains and torsion, is lacking for rats. We hypothesized that healthy rat left ventricles (LVs) exhibit regional differences in cardiac mechanics, which are part of normal function. In this study, images of the LV were obtained with 3D cine displacement encoding with stimulated echoes (DENSE) cardiovascular magnetic resonance in 10 healthy rats. To evaluate regional cardiac mechanics, the LV was divided into basal, mid-ventricular, and apical regions. The myocardium at the mid-LV was further partitioned into four wall segments (i.e. septal, inferior, lateral, and anterior) and three transmural layers (i.e. sub-endocardium, mid-myocardium, and sub-epicardium). The six Lagrangian strain components (i.e. E rr , E cc , E ll , E cl , E rl , and E cr ) were computed from the 3D displacement field and averaged within each region of interest. Torsion was quantified using the circumferential-longitudinal shear angle. While peak systolic E cl differed between the mid-ventricle and apex, the other five components of peak systolic strain were similar across the base, mid-ventricle, and apex. In the mid-LV myocardium, E cc decreased gradually from the sub-endocardial to the sub-epicardial layer. E ll demonstrated significant differences between the four wall segments, with the largest magnitude in the inferior segment. E rr was uniform among the four wall segments. E cl varied along the transmural direction and among wall segments, whereas E rl differed only among the wall segments. E rc was not associated with significant variations. Torsion also varied along the transmural direction and among wall segments. These results provide fundamental insights into the regional contractile function of healthy rat hearts, and form the foundation for future studies on regional changes induced by disease or treatments. Copyright © 2017 John Wiley & Sons, Ltd.

Effects of enzyme-replacement therapy in patients with Anderson-Fabry disease: a prospective long-term cardiac magnetic resonance imaging study.

PubMed

Imbriaco, M; Pisani, A; Spinelli, L; Cuocolo, A; Messalli, G; Capuano, E; Marmo, M; Liuzzi, R; Visciano, B; Cianciaruso, B; Salvatore, M

2009-07-01

Anderson-Fabry disease is a multisystem X linked disorder of lipid metabolism frequently associated with cardiac symptoms, including left ventricular (LV) hypertrophy gradually impairing cardiac function. Evidence showing that enzyme-replacement therapy (ERT) can be effective in reducing LV hypertrophy and improving myocardial function in the long term is limited. This study aimed to assess the long-term effects of ERT with recombinant alpha-galactosidase A (agalsidase beta, Fabrazyme) on LV function and myocardial signal intensity in 11 patients with Anderson-Fabry disease. Eleven patients (eight males, three females) with varying stages of genetically confirmed Anderson-Fabry disease were examined by means of physical examination and magnetic resonance imaging before ERT with agalsidase beta at 1 mg/kg every other week (study 1) and after a mean treatment duration of 45 months (study 2). At 45 months of treatment, LV mass and LV wall thickness had significantly reduced: 188 (SD 60) g versus 153 (47) g, and 16 (4) mm versus 14 (4) mm, respectively. Furthermore, a significant reduction in myocardial T2 relaxation times was noted in all myocardial regions, that is, interventricular septum 80 (5) ms versus 66 (8) ms, apex 79 (10) ms versus 64 (10) ms, and lateral wall 80 (8) ms versus 65 (16) ms. Changes in LV ejection fraction were not significant. Amelioration of clinical symptoms was observed in all patients. Long-term therapy with agalsidase beta at 1 mg/kg every 2 weeks was effective in significantly reducing LV hypertrophy, improving overall cardiac performance and ameliorating clinical symptoms in patients with Anderson-Fabry disease.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lathers, C.M.; Spivey, W.H.; Levin, R.M.

The effect of metoprolol (M) on beta receptor density (BRD) was examined. M (5 mg/kg, p.o., b.i.d.) was given for 2 and 8 wks prior to CO of the left anterior descending artery (LAD) at its origin. BRD, determined by binding of /sup 3/H-dihydroalprenol, was examined in the myocardium (LA = left atrium, RA = right atrium, LV1 = proximal LAD distribution, LV = 2 distal LAD distribution, LV3 = posterior left ventricle, RV = right ventricle, and S = septum. A 2 factor ANOVA followed by simple effect and Newman-Keuls post hoc tests revealed that M produced no effectmore » in BRD in LA, RA, LV2, or S. M increased BRD in LV1, LV3, and RV after 2 wk when compared to no M. In addition, BRD in LV3 and RV were also greater at 2 wk than after 8 wk M. The data indicate that there are regional differences in the beta adrenergic receptor densities among the areas of the heart and within the left ventricle. Chronic dosing with M produced increased BRD in only some of the areas of the heart. These differences may be related to functional differences in the various areas of the heart after CO.« less

Detecting Subclinical Biventricular Impairment in Scleroderma Patients by Use of Pulsed-Wave Tissue Doppler Imaging

PubMed Central

Can, Ilknur; Onat, Ahmet Mesut; Aytemir, Kudret; Akdogan, Ali; Ureten, Kemal; Kiraz, Sedat; Ertenli, Ihsan; Tokgozoglu, Lale; Oto, Ali

2009-01-01

Systemic scleroderma is a disease that is characterized by excessive fibroblastic activity and collagen deposition in various organs, including the heart. We sought to evaluate the limits of biventricular function as derived noninvasively from pulsed-wave tissue Doppler imaging (TDI) of tricuspid and mitral annular motion in patients who had scleroderma. We enrolled 24 patients with scleroderma (study group; mean age, 49 ± 11 yr; 20 women) and 24 healthy participants (control group; mean age, 51 ± 9 yr; 19 women). Persons with cardiovascular risk factors were excluded. We obtained images by conventional echocardiography and by pulsed-wave TDI, measuring the respective peak systolic velocities (S, Sm) and peak early (E, Em) and late (A, Am) diastolic velocities. Mean Sm, mean Em, and mean Am were averages of the 4 measured sites (anterior, inferior, lateral, and septal). We calculated noninvasive estimates of left ventricular (LV) filling pressure by dividing E velocities (from the mitral inflow) by Em velocities (E/Em ratios). Biventricular regional Sm, regional LV myocardial Em, and ratios of myocardial Em/atrial component velocity (Em/Am) for the LV, and mean Sm, mean Em, and mean Em/mean Am ratios for the LV were significantly lower in the study group. The E/Em ratio was higher in the study group (7.3 ± 2.6 vs 5.2 ± 1.0, P = 0.01). Global LV systolic and diastolic function did not differ between the groups. Tissue Doppler imaging complements conventional echocardiography in detecting subclinical biventricular impairment in patients with scleroderma who have normal global measurements. PMID:19436783

Assessment of global and regional left ventricular function using 64-slice multislice computed tomography and 2D echocardiography: a comparison with cardiac magnetic resonance.

PubMed

Annuar, Bin Rapaee; Liew, Chee Khoon; Chin, Sze Piaw; Ong, Tiong Kiam; Seyfarth, M Tobias; Chan, Wei Ling; Fong, Yean Yip; Ang, Choon Kiat; Lin, Naing; Liew, Houng Bang; Sim, Kui Hian

2008-01-01

To compare the assessment of global and regional left ventricular (LV) function using 64-slice multislice computed tomography (MSCT), 2D echocardiography (2DE) and cardiac magnetic resonance (CMR). Thirty-two consecutive patients (mean age, 56.5+/-9.7 years) referred for evaluation of coronary artery using 64-slice MSCT also underwent 2DE and CMR within 48h. The global left ventricular function which include left ventricular ejection fraction (LVEF), left ventricular end diastolic volume (LVdV) and left ventricular end systolic volume (LVsV) were determine using the three modalities. Regional wall motion (RWM) was assessed visually in all three modalities. The CMR served as the gold standard for the comparison between 64-slice MSCT with CMR and 2DE with CMR. Statistical analysis included Pearson correlation coefficient, Bland-Altman plots and kappa-statistics. The 64-slice MSCT agreed well with CMR for assessment of LVEF (r=0.92; p<0.0001), LVdV (r=0.98; p<0.0001) and LVsV (r=0.98; p<0.0001). In comparison with 64-slice MSCT, 2DE showed moderate correlation with CMR for the assessment of LVEF (r=0.84; p<0.0001), LVdV (r=0.83; p<0.0001) and LVsV (r=0.80; p<0.0001). However in RWM analysis, 2DE showed better accuracy than 64-slice MSCT (94.3% versus 82.4%) and closer agreement (kappa=0.89 versus 0.63) with CMR. 64-Slice MSCT correlates strongly with CMR in global LV function however in regional LV function 2DE showed better agreement with CMR than 64-slice MSCT.

Different regions of latest electrical activation during left bundle-branch block and right ventricular pacing in cardiac resynchronization therapy patients determined by coronary venous electro-anatomic mapping.

PubMed

Mafi Rad, Masih; Blaauw, Yuri; Dinh, Trang; Pison, Laurent; Crijns, Harry J; Prinzen, Frits W; Vernooy, Kevin

2014-11-01

Current targeted left ventricular (LV) lead placement strategy is directed at the latest activated region during intrinsic activation. However, cardiac resynchronization therapy (CRT) is most commonly applied by simultaneous LV and right ventricular (RV) pacing without contribution from intrinsic conduction. Therefore, targeting the LV lead to the latest activated region during RV pacing might be more appropriate. We investigated the difference in LV electrical activation sequence between left bundle-branch block (LBBB) and RV apex (RVA) pacing using coronary venous electro-anatomic mapping (EAM). Twenty consecutive CRT candidates with LBBB underwent intra-procedural coronary venous EAM during intrinsic activation and RVA pacing using EnSite NavX. Left ventricular lead placement was aimed at the latest activated region during LBBB according to current recommendations. In all patients, LBBB was associated with a circumferential LV activation pattern, whereas RVA pacing resulted in activation from the apex of the heart to the base. In 10 of 20 patients, RVA pacing shifted the latest activated region relative to LBBB. In 18 of 20 patients, the LV lead was successfully positioned in the latest activated region during LBBB. For the whole study population, LV lead electrical delay, expressed as percentage of QRS duration, was significantly shorter during RVA pacing than during LBBB (72 ± 13 vs. 82 ± 5%, P = 0.035). Right ventricular apex pacing alters LV electrical activation pattern in CRT patients with LBBB, and shifts the latest activated region in a significant proportion of these patients. These findings warrant reconsideration of the current practice of LV lead targeting for CRT. © 2014 The Authors. European Journal of Heart Failure © 2014 European Society of Cardiology.

Dermal Filler Injection: A Novel Approach for Limiting Infarct Expansion

PubMed Central

Ryan, Liam P.; Matsuzaki, Kanji; Noma, Mio; Jackson, Benjamin M.; Eperjesi, Thomas J.; Plappert, Theodore J.; St. John-Sutton, Martin G.; Gorman, Joseph H.; Gorman, Robert C.

2011-01-01

Background Early infarct expansion after coronary occlusion compromises contractile function in perfused myocardial regions and promotes adverse long-term left ventricular (LV) remodeling. We hypothesized that injection of a tissue-expanding dermal filler material into a myocardial infarction (MI) would attenuate infarct expansion and limit LV remodeling. Methods Fifteen sheep were subjected to an anteroapical MI involving approximately 20% of the LV followed by the injection of 1.3 mL of a calcium hydroxyapatite–based dermal filler into the infarct. Real-time three-dimensional echocardiography was performed at baseline, 30 minutes after MI, and 15 minutes after injection to assess infarct expansion. Sixteen additional sheep were subjected to the same infarction and followed echocardiographically and hemodynamically for 4 weeks after MI to assess chronic remodeling. Eight animals had injection with dermal filler as described above immediately after MI, and 8 animals were injected with an equal amount of saline solution. Results All animals exhibited infarct expansion soon after coronary occlusion. The regional ejection fraction of the apex became negative after infarction, consistent with systolic dyskinesia. Injection of the dermal filler converted the apical wall motion from dyskinetic to akinetic and resulted immediately in significant decreases in global, regional, and segmental LV volumes. Chronically, relative to saline control, dermal filler injection significantly reduced LV end-systolic volume (62.2 ± 3.6 mL versus 44.5 ± 3.9 mL; p < 0.05) and improved global ejection fraction (0.295 ± 0.016 versus 0.373 ± 0.017; p < 0.05) at 4 weeks after infarction. Conclusions Injection of an acellular dermal filler into an MI immediately after coronary occlusion reduces early infarct expansion and limits chronic LV remodeling. PMID:19101288

LV mechanical dispersion as a predictor of ventricular arrhythmia in patients with advanced systolic heart failure : A pilot study.

PubMed

Banasik, G; Segiet, O; Elwart, M; Szulik, M; Lenarczyk, R; Kalarus, Z; Kukulski, T

2016-11-01

Myocardial mechanical dyssynchrony induced by the presence of postinfarction scar and/or conduction abnormalities in patients with a left ventricular ejection fraction (LVEF) of < 35 % may be associated with a greater propensity toward inducing serious ventricular arrhythmia [(ventricular tachycardia (VT), ventricular fibrillation (VF)] and sudden cardiac death. The assessment of regional myocardial function using tissue Doppler echocardiography (TDE) allows for noninvasive analysis of regional mechanical dysfunction (LV mechanical dispersion). The aim of this study was to evaluate the TDE-based mechanical dispersion as a potential echocardiographic predictor of VT/VF. The study group consisted of 47 consecutive ambulatory patients with implanted cardiac resynchronization therapy-defibrillator (CRT-D) devices who were divided into two groups: Group 1 (n = 29) comprised patients with recorded episodes of VT/VF, in whom baseline TDE data were available, and group 2 (n = 18) comprised patients without registered VT/VF in the device memory within 4 years after implantation. LV mechanical dispersion was defined as the standard deviation of the time measured from the beginning of the QRS complex to the peak longitudinal strain in apical four-chamber and two-chamber views. A retrospective quantitative assessment of LV regional deformation was based on the color tissue velocity recordings. The average time to event after implantation was 345 days. Patients with electrical events demonstrated greater mechanical dispersion: 99.14 ± 33.60 vs. 72.98 ± 19.70, p=0.002. During the 4-year follow-up, patients with documented VT/VF were characterized by significantly higher LV mechanical dispersion as compared with patients without electrical events. Measurement of LV mechanical dispersion might be helpful in determining the risk of sudden cardiac death.

Identification and characterization of a highly variable region in mitochondrial genomes of fusarium species and analysis of power generation from microbial fuel cells

NASA Astrophysics Data System (ADS)

Hamzah, Haider Mousa

In the microbial fuel cell (MFC) project, power generation from Shewanella oneidensis MR-1 was analyzed looking for a novel system for both energy generation and sustainability. The results suggest the possibility of generating electricity from different organic substances, which include agricultural and industrial by-products. Shewanella oneidensis MR-1 generates usable electrons at 30°C using both submerged and solid state cultures. In the MFC biocathode experiment, most of the CO2 generated at the anodic chamber was converted into bicarbonate due the activity of carbonic anhydrase (CA) of the Gluconobacter sp.33 strain. These findings demonstrate the possibility of generation of electricity while at the same time allowing the biomimetic sequestration of CO2 using bacterial CA. In the mitochondrial genomes project, the filamentous fungal species Fusarium oxysporum was used as a model. This species causes wilt of several important agricultural crops. A previous study revealed that a highly variable region (HVR) in the mitochondrial DNA (mtDNA) of three species of Fusarium contained a large, variable unidentified open reading frame (LV-uORF). Using specific primers for two regions of the LV-uORF, six strains were found to contain the ORF by PCR and database searches identified 18 other strains outside of the Fusarium oxysporum species complex. The LV-uORF was also identified in three isolates of the F. oxysporum species complex. Interestingly, several F. oxysporum isolates lack the LV-uORF and instead contain 13 ORFs in the HVR, nine of which are unidentified. The high GC content and codon usage of the LV-uORF indicate that it did not co-evolve with other mt genes and was horizontally acquired and was introduced to the Fusarium lineage prior to speciation. The nonsynonymous/synonymous (dN/dS) ratio of the LV-uORFs (0.43) suggests it is under purifying selection and the putative polypeptide is predicted to be located in the mitochondrial membrane. Growth assays indicate that F. oxysporum strains containing the LV-uORF are able to tolerate high concentrations of zinc chloride, whereas those having the alternative HVR configuration are inhibited. This work suggests that fungal mitochondria can acquire additional genes and possibly novel functions and will guide studies that aim to assess the functional roles of hypothetical mitochondrial ORFs in filamentous fungi.

Doppler echocardiographic myocardial stunning index predicts recovery of left ventricular systolic function after primary percutaneous coronary intervention.

PubMed

Sharif, Dawod; Matanis, Wisam; Sharif-Rasslan, Amal; Rosenschein, Uri

2016-10-01

Myocardial stunning is responsible for partially reversible left ventricular (LV) systolic dysfunction after successful primary percutaneous coronary intervention (PPCI) in patients with acute ST-elevation myocardial infarction (STEMI). To test the hypothesis that early coronary blood flow (CBF) to LV systolic function ratios, as an equivalent to LV stunning index (SI), predict recovery of LV systolic function after PPCI in patients with acute STEMI. Twenty-four patients with acute anterior STEMI who had successful PPCI were evaluated and compared to 96 control subjects. Transthoracic echocardiography with measurement of LV ejection fraction (EF), LV, and left anterior descending (LAD) coronary artery area wall-motion score index (WMSI) as well as Doppler sampling of LAD blood velocities, early after PPCI and 5 days later, were performed. SI was evaluated as the early ratio of CBF parameters in the LAD to LV systolic function parameters. Early SI-LVEF well predicted late LVEF (r=.51, P<.01) and the change in LVEF (r=.48, P<.017). Early SI-LVMSI predicted well late LVEF (r=.56, P<.006) and the change in LVEF (r=.46, P<.028). Early SI-LADWMSI predicted late LVEF (r=.44, P<.028). Other SI indices measured as other LAD-CBF to LV systolic function parameters were not predictive of late LV systolic function. LV stunning indices measured as early LAD flow to LVEF, LVWMSI, and LADWMSI ratios well predicted late LVEF and the change in LVEF. Thus, greater early coronary artery flow to LV systolic function parameter ratios predict a better improvement in late LV systolic function after PPCI. © 2016, Wiley Periodicals, Inc.

Fast left ventricle tracking in CMR images using localized anatomical affine optical flow

NASA Astrophysics Data System (ADS)

Queirós, Sandro; Vilaça, João. L.; Morais, Pedro; Fonseca, Jaime C.; D'hooge, Jan; Barbosa, Daniel

2015-03-01

In daily cardiology practice, assessment of left ventricular (LV) global function using non-invasive imaging remains central for the diagnosis and follow-up of patients with cardiovascular diseases. Despite the different methodologies currently accessible for LV segmentation in cardiac magnetic resonance (CMR) images, a fast and complete LV delineation is still limitedly available for routine use. In this study, a localized anatomically constrained affine optical flow method is proposed for fast and automatic LV tracking throughout the full cardiac cycle in short-axis CMR images. Starting from an automatically delineated LV in the end-diastolic frame, the endocardial and epicardial boundaries are propagated by estimating the motion between adjacent cardiac phases using optical flow. In order to reduce the computational burden, the motion is only estimated in an anatomical region of interest around the tracked boundaries and subsequently integrated into a local affine motion model. Such localized estimation enables to capture complex motion patterns, while still being spatially consistent. The method was validated on 45 CMR datasets taken from the 2009 MICCAI LV segmentation challenge. The proposed approach proved to be robust and efficient, with an average distance error of 2.1 mm and a correlation with reference ejection fraction of 0.98 (1.9 +/- 4.5%). Moreover, it showed to be fast, taking 5 seconds for the tracking of a full 4D dataset (30 ms per image). Overall, a novel fast, robust and accurate LV tracking methodology was proposed, enabling accurate assessment of relevant global function cardiac indices, such as volumes and ejection fraction

Nucleotide sequence analysis establishes the role of endogenous murine leukemia virus DNA segments in formation of recombinant mink cell focus-forming murine leukemia viruses.

PubMed Central

Khan, A S

1984-01-01

The sequence of 363 nucleotides near the 3' end of the pol gene and 564 nucleotides from the 5' terminus of the env gene in an endogenous murine leukemia viral (MuLV) DNA segment, cloned from AKR/J mouse DNA and designated as A-12, was obtained. For comparison, the nucleotide sequence in an analogous portion of AKR mink cell focus-forming (MCF) 247 MuLV provirus was also determined. Sequence features unique to MCF247 MuLV DNA in the 3' pol and 5' env regions were identified by comparison with nucleotide sequences in analogous regions of NFS -Th-1 xenotropic and AKR ecotropic MuLV proviruses. These included (i) an insertion of 12 base pairs encoding four amino acids located 60 base pairs from the 3' terminus of the pol gene and immediately preceding the env gene, (ii) the deletion of 12 base pairs (encoding four amino acids) and the insertion of 3 base pairs (encoding one amino acid) in the 5' portion of the env gene, and (iii) single base substitutions resulting in 2 MCF247 -specific amino acids in the 3' pol and 23 in the 5' env regions. Nucleotide sequence comparison involving the 3' pol and 5' env regions of AKR MCF247 , NFS xenotropic, and AKR ecotropic MuLV proviruses with the cloned endogenous MuLV DNA indicated that MCF247 proviral DNA sequences were conserved in the cloned endogenous MuLV proviral segment. In fact, total nucleotide sequence identity existed between the endogenous MuLV DNA and the MCF247 MuLV provirus in the 3' portion of the pol gene. In the 5' env region, only 4 of 564 nucleotides were different, resulting in three amino acid changes between AKR MCF247 MuLV DNA and the endogenous MuLV DNA present in clone A-12. In addition, nucleotide sequence comparison indicated that Moloney-and Friend-MCF MuLVs were also highly related in the 3' pol and 5' env regions to the cloned endogenous MuLV DNA. These results establish the role of endogenous MuLV DNA segments in generation of recombinant MCF viruses. PMID:6328017

Increased left ventricular mass and diastolic dysfunction are associated with endothelial dysfunction in normotensive offspring of subjects with essential hypertension.

PubMed

Zizek, Bogomir; Poredos, Pavel

2007-01-01

We aimed to investigate left ventricular (LV) morphology and function in normotensive offspring of subjects with essential hypertension (familial trait - FT), and to determine the association between LV mass and determinants of LV diastolic function and endothelium-dependent (NO-mediated) dilation of the brachial artery (BA). The study encompassed 76 volunteers of whom 44 were normotonics with FT aged 28-39 (mean 33) years and 32 age-matched controls without FT. LV mass and LV diastolic function was measured using conventional echocardiography and tissue Doppler imaging (TDI). LV diastolic filling properties were assessed and reported as the peak E/A wave ratio, and peak septal annular velocities (E(m) and E(m)/A(m) ratio) on TDI. Using high-resolution ultrasound, BA diameters at rest and during reactive hyperaemia (flow-mediated dilation--FMD) were measured. In subjects with FT, the LV mass index was higher than in controls (92.14+/-24.02 vs 70.08+/-20.58); p<0.001). Offspring of hypertensive families had worse LV diastolic function than control subjects (lower E/A ratio, lower E(m) and E(m)/A(m) ratio; p<0.001). In subjects with FT, FMD was decreased compared with the controls (6.11+/-3.28% vs 10.20+/-2.07%; p<0.001). LV mass index and E(m)/A(m) ratio were associated with FMD (p<0.001). In normotensive individuals with FT, LV morphological and functional changes were found. We demonstrated that an increase in LV mass and alterations in LV diastolic function are related to endothelial dysfunction.

Analysis of Regional Left Ventricular Strain in Patients with Chagas Disease and Normal Left Ventricular Systolic Function.

PubMed

Gomes, Victor Augusto M; Alves, Gabriel F; Hadlich, Marcelo; Azevedo, Clerio F; Pereira, Iane M; Santos, Carla Renata F; Brasil, Pedro Emmanuel A A; Sangenis, Luiz Henrique C; Cunha, Ademir B; Xavier, Sergio S; Saraiva, Roberto M

2016-07-01

Chagas heart disease has a high socioeconomic burden, and any strategy to detect early myocardial damage is welcome. Speckle-tracking echocardiography assesses global and segmental left ventricular (LV) systolic function, yielding values of two-dimensional strain (ε). The aim of this study was to determine if patients with chronic Chagas disease and normal LV ejection fractions present abnormalities in global and segmental LV ε. In this prospective study, patients with Chagas disease with no evidence of cardiac involvement (group I; n = 83) or at stage A of the cardiac form (i.e., with changes limited to the electrocardiogram) (group A; n = 42) and 43 control subjects (group C) underwent evaluation of global and segmental LV ε by speckle-tracking echocardiography. A subset of randomly selected patients in group A underwent cardiac magnetic resonance imaging and repeated echocardiography 3.5 ± 0.8 years after the first evaluation. Mean age, chamber dimensions, and LV ejection fraction were similar among the groups. Global longitudinal (group C, -19 ± 2%; group I, -19 ± 2%; group A, -19 ± 2%), circumferential (group C, -19 ± 3%; group I, -20 ± 3%; group A, -19 ± 3%), and radial (group C, 46 ± 10%; group I, 45 ± 13%; group A, 42 ± 14%) LV ε were similar among the groups. Segmental longitudinal, circumferential, and radial LV ε were similar across the studied groups. Seven of 14 patients had areas of fibrosis on cardiac magnetic resonance imaging. Patients with fibrosis had lower global longitudinal (-15 ± 2% vs -18 ± 2%, P = .004), circumferential (-14 ± 2% vs -19 ± 2%, P = .002), and radial LV ε (36 ± 13% vs 54 ± 12%, P = .02) than those without cardiac fibrosis despite similar LV ejection fractions. Patients with fibrosis had lower radial LV ε in the basal inferoseptal wall than patients without cardiac fibrosis (27 ± 17% vs 60 ± 15%, P = .04). Patients with chronic Chagas disease and normal global and segmental LV systolic function on two-dimensional echocardiography had global and segmental LV ε similar to that of control subjects. However, those in the early stages of the cardiac form and cardiac fibrosis had lower global longitudinal, circumferential, and radial LV ε. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Sequential evaluation of coronary flow patterns after primary angioplasty in acute anterior ST-elevation myocardial infarction predicts recovery of left ventricular systolic function.

PubMed

Sharif, Dawod; Sharif-Rasslan, Amal; Makhoul, Nabeel; Shefer, Arie; Hassan, Amin; Rosenschein, Uri

2014-05-01

Function of the microcirculation after primary percutaneous coronary intervention (PCI) is dynamic and contributes to unpredictability of recovery of left ventricular (LV) systolic function. This study was conducted to evaluate sequential Doppler velocity parameters of the left anterior descending coronary artery (LAD) in predicting recovery of global and regional LV systolic function. Thirty-five consecutive patients, 24 males, age 59 ± 12 years, with acute anterior ST-elevation myocardial infarction (STEMI) who had primary PCI were studied. Thrombolysis in myocardial infarction (TIMI) and myocardial blush grades were evaluated. Transthoracic echocardiographic (TTE) studies, evaluation of left ventricular ejection fraction (LVEF), LAD territory wall-motion score index (WMSI), and sampling of LAD Doppler velocities up to 6 hours post-PCI, 48 hours postprocedure, and predischarge were performed. Thrombolysis in myocardial infarction grade before PCI averaged 0.86 ± 1.19 and post-PCI 2.89 ± 0.32, P < 0.05. Myocardial blush grade before PCI was 0.41 ± 0.98 and after PCI 2.22 ± 0.93, P < 0.05. Diastolic velocity deceleration time (DDT) in the LAD early after PCI was less than 600 ms in 16 subjects. Immediately after PCI, in subjects with DDT > 600 ms, LVEF was 38.5 ± 6% and predischarge 49.2 ± 8.7%, P = 9.77 × 10−5 and LAD-WMSI decreased from 2 ± 0.38 to 1.4 ± 0.48, P = 0.000163. In subjects with DDT < 600 ms LAD-WMSI did not change significantly. Early and minimal LAD-DDT correlated with improvement in LV systolic function, r = 0.6, whereas post-PCI blush grade had lower correlation with LVEF, r = 0.39. Global and regional LV systolic function after PCI in acute anterior MI can be predicted by LAD-DDT better than by post-PCI myocardial blush.

Divergent Effects of Losartan and Metoprolol on Cardiac Remodeling, C‐kit+ Cells, Proliferation and Apoptosis in the Left Ventricle after Myocardial Infarction

PubMed Central

Serpi, Raisa; Tolonen, Anna‐Maria; Tenhunen, Olli; Pieviläinen, Oskari; Kubin, Anna‐Maria; Vaskivuo, Tommi; Soini, Ylermi; Kerkelä, Risto; Leskinen, Hanna; Ruskoaho, Heikki

2009-01-01

Abstract There is strong evidence for the use of angiotensin converting enzyme inhibitors and beta‐blockers to reduce morbidity and mortality in patients with myocardial infarction (MI), whereas the effect of angiotensin receptor blockers is less clear. We evaluated the effects of an angiotensin receptor blocker losartan and a beta‐blocker metoprolol on left ventricular (LV) remodeling, c‐kit+ cells, proliferation, fibrosis, apoptosis, and angiogenesis using a model of coronary ligation in rats. Metoprolol treatment for 2 weeks improved LV systolic function. In contrast, losartan triggered deleterious structural remodeling and functional deterioration of LV systolic function, ejection fraction being 41% and fractional shortening 47% lower in losartan group than in controls 2 weeks after MI. The number of c‐kit+ cells as well as expression of Ki‐67 was increased by metoprolol. Losartan‐induced thinning of the anterior wall and ventricular dilation were associated with increased apoptosis and fibrosis, while losartan had no effect on the expression of c‐kit or Ki‐67. Metoprolol or losartan had no effect on microvessel density. These results demonstrate that beta‐blocker treatment attenuated adverse remodeling via c‐kit+ cells and proliferation, whereas angiotensin receptor blocker‐induced worsening of LV systolic function was associated with increased apoptosis and fibrosis in the peri‐infarct region. PMID:20443934

Distinctive receptor binding properties of the surface glycoprotein of a natural feline leukemia virus isolate with unusual disease spectrum.

PubMed

Bolin, Lisa L; Chandhasin, Chandtip; Lobelle-Rich, Patricia A; Albritton, Lorraine M; Levy, Laura S

2011-05-13

Feline leukemia virus (FeLV)-945, a member of the FeLV-A subgroup, was previously isolated from a cohort of naturally infected cats. An unusual multicentric lymphoma of non-T-cell origin was observed in natural and experimental infection with FeLV-945. Previous studies implicated the FeLV-945 surface glycoprotein (SU) as a determinant of disease outcome by an as yet unknown mechanism. The present studies demonstrate that FeLV-945 SU confers distinctive properties of binding to the cell surface receptor. Virions bearing the FeLV-945 Env protein were observed to bind the cell surface receptor with significantly increased efficiency, as was soluble FeLV-945 SU protein, as compared to the corresponding virions or soluble protein from a prototype FeLV-A isolate. SU proteins cloned from other cohort isolates exhibited increased binding efficiency comparable to or greater than FeLV-945 SU. Mutational analysis implicated a domain containing variable region B (VRB) to be the major determinant of increased receptor binding, and identified a single residue, valine 186, to be responsible for the effect. The FeLV-945 SU protein binds its cell surface receptor, feTHTR1, with significantly greater efficiency than does that of prototype FeLV-A (FeLV-A/61E) when present on the surface of virus particles or in soluble form, demonstrating a 2-fold difference in the relative dissociation constant. The results implicate a single residue, valine 186, as the major determinant of increased binding affinity. Computational modeling suggests a molecular mechanism by which residue 186 interacts with the receptor-binding domain through residue glutamine 110 to effect increased binding affinity. Through its increased receptor binding affinity, FeLV-945 SU might function in pathogenesis by increasing the rate of virus entry and spread in vivo, or by facilitating entry into a novel target cell with a low receptor density.

Cardiac mechanics and heart rate variability in patients with systemic sclerosis: the association that we should not miss.

PubMed

Zlatanovic, Maja; Tadic, Marijana; Celic, Vera; Ivanovic, Branislava; Stevanovic, Ana; Damjanov, Nemanja

2017-01-01

We aimed to determine left ventricular (LV) and right ventricular (RV) structure, function and mechanics, as well as heart rate variability (HRV), and their relationship, in patients with systemic sclerosis (SSc). The study included 41 SSc patients and 30 age-matched healthy volunteers. All the patients underwent clinical examination, serological tests, pulmonary function testing, 24-h Holter monitoring and complete two-dimensional echocardiography including strain analysis. The parameters of LV structure (interventricular septum thickness and LV mass index) and RV structure (RV wall thickness) were significantly higher in SSc patients. LV and RV diastolic function (estimated by mitral and tricuspid E/e' ratio) was significantly impaired in SSc group comparing with the healthy controls. LV and RV longitudinal function was significantly deteriorated in SSc patients. LV circumferential strain was also significantly lower in SSc group, whereas LV radial strain was similar between the observed groups. All parameters of time and frequency domain of HRV were decreased in SSc patients. LV and RV cardiac remodeling parameters, particularly diastolic function and longitudinal strain, were associated with HRV indices without regard to the main demographic or the clinical and echocardiographic characteristics. Rodnan Skin Score was also independently associated with biventricular cardiac remodeling in SSc patients. LV and RV structure, function and mechanics, as well as autonomic nervous function, were significantly impaired in SSc patients. There is the significant association between biventricular cardiac remodeling and autonomic function in these patients, which could be useful for their everyday clinical assessment.

Impairment of visuospatial/visuoconstructional skills in multiple sclerosis patients: the correlation with regional lesion load and subcortical atrophy.

PubMed

Marasescu, R; Cerezo Garcia, M; Aladro Benito, Y

2016-04-01

About 20% to 26% of patients with multiple sclerosis (MS) show alterations in visuospatial/visuoconstructive (VS-VC) skills even though temporo-parieto-occipital impairment is a frequent finding in magnetic resonance imaging. No studies have specifically analysed the relationship between these functions and lesion volume (LV) in these specific brain areas. To evaluate the relationship between VS-VC impairment and magnetic resonance imaging temporo-parieto-occipital LV with subcortical atrophy in patients with MS. Of 100 MS patients undergoing a routine neuropsychological evaluation, 21 were selected because they displayed VS-VC impairments in the following tests: Incomplete picture, Block design (WAIS-III), and Rey-Osterrieth complex figure test. We also selected 13 MS patients without cognitive impairment (control group). Regional LV was measured in FLAIR and T1-weighted images using a semiautomated method; subcortical atrophy was measured by bicaudate ratio and third ventricle width. Partial correlations (controlling for age and years of school) and linear regression analysis were employed to analyse correlations between magnetic resonance imaging parameters and cognitive performance. All measures of LV and brain atrophy were significantly higher in patients with cognitive impairment. Regional LV, bicaudate ratio, and third ventricle width are significantly and inversely correlated with cognitive performance; the strongest correlation was between third ventricle width and VC performance (Block design: P=.001; Rey-Osterrieth complex figure: P<.000). In the multivariate analysis, third ventricle width only had a significant effect on performance of VC tasks (Block design: P=.000; Rey-Osterrieth complex figure: P=.000), and regional FLAIR VL was linked to the VS task (Incomplete picture; P=.002). Measures of subcortical atrophy explain the variations in performance on visuocostructive tasks, and regional FLAIR VL measures are linked to VS tasks. Copyright © 2015 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

Left Ventricular Myocardial Function in Children With Pulmonary Hypertension: Relation to Right Ventricular Performance and Hemodynamics.

PubMed

Burkett, Dale A; Slorach, Cameron; Patel, Sonali S; Redington, Andrew N; Ivy, D Dunbar; Mertens, Luc; Younoszai, Adel K; Friedberg, Mark K

2015-08-01

Through ventricular interdependence, pulmonary hypertension (PH) induces left ventricular (LV) dysfunction. We hypothesized that LV strain/strain rate, surrogate measures of myocardial contractility, are reduced in pediatric PH and relate to invasive hemodynamics, right ventricular strain, and functional measures of PH. At 2 institutions, echocardiography was prospectively performed in 54 pediatric PH patients during cardiac catheterization, and in 54 matched controls. Patients with PH had reduced LV global longitudinal strain (LS; -18.8 [-17.3 to -20.4]% versus -20.2 [-19.0 to -20.9]%; P=0.0046) predominantly because of reduced basal (-12.9 [-10.8 to -16.3]% versus -17.9 [-14.5 to -20.7]%; P<0.0001) and mid (-17.5 [-15.5 to -19.0]% versus -21.1 [-19.1 to -23.0]%; P<0.0001) septal strain. Basal global circumferential strain was reduced (-18.7 [-15.7 to -22.1]% versus -20.6 [-19.0 to -22.5]%; P=0.0098), as were septal and free-wall segments. Mid circumferential strain was reduced within the free-wall. Strain rates were reduced in similar patterns. Basal septum LS, the combined average LS of basal and mid interventricular septal segments, correlated strongly with degree of PH (r=0.66; P<0.0001), pulmonary vascular resistance (r=0.60; P<0.0001), and right ventricular free-wall LS (r=0.64; P<0.0001). Brain natriuretic peptide levels correlated moderately with septal LS (r=0.48; P=0.0038). PH functional class correlated moderately with LV free-wall LS (r=-0.48; P=0.0051). The septum, shared between ventricles and affected by septal shift, was the most affected LV region in PH. Pediatric PH patients demonstrate reduced LV strain/strain rate, predominantly within the septum, with relationships to invasive hemodynamics, right ventricular strain, and functional PH measures. © 2015 American Heart Association, Inc.

Comparison of left ventricular structure and function in primary aldosteronism and essential hypertension by echocardiography.

PubMed

Yang, Yan; Zhu, Li-Min; Xu, Jian-Zhong; Tang, Xiao-Feng; Gao, Ping-Jin

2017-03-01

Primary aldosteronism (PA) is the most common secondary cause of hypertension. The present study investigated differences in left ventricular structure and function between hypertensive patients with PA and sucjects with essential hypertension (EH). One hundred patients with PA and 100 controls with EH were matched for age, gender, and 24-h ambulatory monitoring blood pressure (BP). Left ventricular mass index (LVMI), left atrial volume index (LAVI) and ejection fraction were calculated. LV diastolic function was estimated as the ratio of the early diastolic velocities (E) from transmitral inflow to the early diastolic velocities (e') of tissue Doppler at mitral annulus. PA and EH patients had similar LV dimensions, LV wall thicknesses, LVMI and LV systolic function. PA was associated with greater impairment in diastolic function, as reflected by the lower e' (P=0.004), higher E/e' ratio (P=0.005) and higher LAVI (P=0.02). The LV geometric dimensions and patterns of LV hypertrophy were similar between male patients from the PA and EH groups. However, in female patients, PA was correlated with higher LV internal dimensions (P=0.001), higher LVMI (P=0.04) and lower relative wall thickness (RWT, P=0.001). Multivariate analysis showed that LV diastolic function was independently correlated with age (β=0.416, P<0.001), 24-h systolic BP (β=0.238, P=0.016) and serum potassium (β=-0.201, P=0.036) in PA patients. In conclusion, PA appears to contribute to the impairment of LV diastolic function in both sexes as well as the higher prevalence of eccentric hypertrophy in women than in men compared with EH. Age, 24-h systolic BP and serum potassium levels are independent risk factors for LV diastolic function in PA patients.

Left ventricle: fully automated segmentation based on spatiotemporal continuity and myocardium information in cine cardiac magnetic resonance imaging (LV-FAST).

PubMed

Wang, Lijia; Pei, Mengchao; Codella, Noel C F; Kochar, Minisha; Weinsaft, Jonathan W; Li, Jianqi; Prince, Martin R; Wang, Yi

2015-01-01

CMR quantification of LV chamber volumes typically and manually defines the basal-most LV, which adds processing time and user-dependence. This study developed an LV segmentation method that is fully automated based on the spatiotemporal continuity of the LV (LV-FAST). An iteratively decreasing threshold region growing approach was used first from the midventricle to the apex, until the LV area and shape discontinued, and then from midventricle to the base, until less than 50% of the myocardium circumference was observable. Region growth was constrained by LV spatiotemporal continuity to improve robustness of apical and basal segmentations. The LV-FAST method was compared with manual tracing on cardiac cine MRI data of 45 consecutive patients. Of the 45 patients, LV-FAST and manual selection identified the same apical slices at both ED and ES and the same basal slices at both ED and ES in 38, 38, 38, and 41 cases, respectively, and their measurements agreed within -1.6 ± 8.7 mL, -1.4 ± 7.8 mL, and 1.0 ± 5.8% for EDV, ESV, and EF, respectively. LV-FAST allowed LV volume-time course quantitatively measured within 3 seconds on a standard desktop computer, which is fast and accurate for processing the cine volumetric cardiac MRI data, and enables LV filling course quantification over the cardiac cycle.

Association between left ventricular mechanics and diffuse myocardial fibrosis in patients with repaired Tetralogy of Fallot: a cross-sectional study.

PubMed

Haggerty, Christopher M; Suever, Jonathan D; Pulenthiran, Arichanah; Mejia-Spiegeler, Abba; Wehner, Gregory J; Jing, Linyuan; Charnigo, Richard J; Fornwalt, Brandon K; Fogel, Mark A

2017-12-11

Patients with repaired tetralogy of Fallot (TOF) have progressive, adverse biventricular remodeling, leading to abnormal contractile mechanics. Defining the mechanisms underlying this dysfunction, such as diffuse myocardial fibrosis, may provide insights into poor long-term outcomes. We hypothesized that left ventricular (LV) diffuse fibrosis is related to impaired LV mechanics. Patients with TOF were evaluated with cardiac magnetic resonance in which modified Look-Locker (MOLLI) T1-mapping and spiral cine Displacement encoding (DENSE) sequences were acquired at three LV short-axis positions. Linear mixed modeling was used to define the association between regional LV mechanics from DENSE based on regional T1-derived diffuse fibrosis measures, such as extracellular volume fraction (ECV). Forty patients (26 ± 11 years) were included. LV ECV was generally within normal range (0.24 ± 0.05). For LV mechanics, peak circumferential strains (-15 ± 3%) and dyssynchrony indices (16 ± 8 ms) were moderately impaired, while peak radial strains (29 ± 8%) were generally normal. After adjusting for patient age, sex, and regional LV differences, ECV was associated with log-adjusted LV dyssynchrony index (β = 0.67) and peak LV radial strain (β = -0.36), but not LV circumferential strain. Moreover, post-contrast T1 was associated with log-adjusted LV diastolic circumferential strain rate (β = 0.37). We observed several moderate associations between measures of fibrosis and impaired mechanics, particularly the LV dyssynchrony index and peak radial strain. Diffuse fibrosis may therefore be a causal factor in some ventricular dysfunction in TOF.

Correlation of transforming growth factor-β1 and tumour necrosis factor levels with left ventricular function in Chagas disease.

PubMed

Curvo, Eduardo Ov; Ferreira, Roberto R; Madeira, Fabiana S; Alves, Gabriel F; Chambela, Mayara C; Mendes, Veronica G; Sangenis, Luiz Henrique C; Waghabi, Mariana C; Saraiva, Roberto M

2018-02-19

Transforming growth factor β1 (TGF-β1) and tumour necrosis factor (TNF) have been implicated in Chagas disease pathophysiology and may correlate with left ventricular (LV) function. We determined whether TGF-β1 and TNF serum levels correlate with LV systolic and diastolic functions and brain natriuretic peptide (BNP) serum levels in chronic Chagas disease. This cross-sectional study included 152 patients with Chagas disease (43% men; 57 ± 12 years old), classified as 53 patients with indeterminate form and 99 patients with cardiac form (stage A: 24, stage B: 25, stage C: 44, stage D: 6). TGF-β1, TNF, and BNP were determined by enzyme-linked immunosorbent assay ELISA. Echocardiogram was used to determine left atrial and LV diameters, as well as LV ejection fraction and diastolic function. TGF-b1 serum levels were lower in stages B, C, and D, while TNF serum levels were higher in stages C and D of the cardiac form. TGF-β1 presented a weak correlation with LV diastolic function and LV ejection fraction. TNF presented a weak correlation with left atrial and LV diameters and LV ejection fraction. TNF is increased, while TGF-β1 is decreased in the cardiac form of chronic Chagas disease. TNF and TGF-β1 serum levels present a weak correlation with LV systolic and diastolic function in Chagas disease patients.

Importance of mitral valve repair associated with left ventricular reconstruction for patients with ischemic cardiomyopathy: a real-time three-dimensional echocardiographic study

NASA Technical Reports Server (NTRS)

Qin, Jian Xin; Shiota, Takahiro; McCarthy, Patrick M.; Asher, Craig R.; Hail, Melanie; Agler, Deborah A.; Popovic, Zoran B.; Greenberg, Neil L.; Smedira, Nicholas G.; Starling, Randall C.;

Reverse remodeling and the mechanism of mitral regurgitation improvement in patients with dilated cardiomyopathy.

PubMed

Kuperstein, Rafael; Blechman, Ido; Ben Zekry, Sagit; Klempfner, Robert; Freimark, Dov; Arad, Michael

2015-01-01

Functional mitral regurgitation (MR) is a common finding in dilated cardiomyopathy. Left ventricular (LV) reverse remodeling with LV size reduction and improvement in LV function is a well recognized phenomenon. We aimed to evaluate the impact of LV remodeling on the mechanism leading to functional MR. Among 188 patients with non-ischemic dilated cardiomyopathy, 10 patients significantly improved their LV function, reduced LV size and MR severity during follow-up (RRMR). A comparison was made between their baseline and follow-up echocardiographic examinations and to a matched-control group of patients who did not improve (no RRMR). LV and left atrium (LA) dimensions and volumes, LV mass (LVM), LV ejection fraction (LVEF) (Simpsons), sphericity index (SI), mitral valve tenting area (TA) coaptation distance (CD), effective regurgitant orifice (ERO), and regurgitant volume were calculated. Multivariable analysis was performed in order to evaluate which echocardiographic parameters related to MR improvement in reverse remodeling. LV and LA dimensions and volumes, LVM, SI, TA, CD, ERO and right ventricle, in the RRMR group significantly decreased at follow-up (p < 0.04 for all). When compared to no RRMR, despite a similar ERO (0.2 ± 0.05 vs. 0.2 ± 0.08, p = 0.13) and a larger regurgitant volume (38 ± 9 vs. 29 ± 8 mL, p = 0.05) and despite similar clinical characteristics and medical treatment we found significantly higher LVEF, smaller LV dimensions and volumes, smaller LVM and SI in the RRMR group (p < 0.05 for all). On multivariable analysis the SI was the sole predictor of RRMR (p = 0.04, OR = 0.76, CI 0.58-0.99). Reverse remodeling characterized by improvement in LV function, reduction in LV size and an associated reduction in MR severity is related to LV SI at baseline.

Relations of Central Hemodynamics and Aortic Stiffness with Left Ventricular Structure and Function: The Framingham Heart Study.

PubMed

Kaess, Bernhard M; Rong, Jian; Larson, Martin G; Hamburg, Naomi M; Vita, Joseph A; Cheng, Susan; Aragam, Jayashree; Levy, Daniel; Benjamin, Emelia J; Vasan, Ramachandran S; Mitchell, Gary F

2016-03-25

The differing relations of steady and pulsatile components of central hemodynamics and aortic stiffness with cardiac dimensions and function have not been fully elucidated. Central hemodynamics and carotid-femoral pulse wave velocity (CFPWV, a measure of aortic stiffness) were measured by arterial tonometry in 5799 participants of the Framingham Heart Study (mean age 51 years, 54% women) and related to echocardiographic left ventricular (LV) dimensions and systolic and diastolic function using multivariable-adjusted partial Pearson correlations. Mean arterial pressure (MAP, steady component of central blood pressure) was associated positively with LV wall thickness (r=0.168; P<0.0001) but showed only a weak direct association with LV diastolic dimension (r=0.035, P=0.006). Central pulse pressure (pulsatile component of central blood pressure) showed a direct correlation with both LV diastolic dimension and LV wall thickness (r=0.08 and 0.044, both P<0.0001 in multivariable models that included MAP). CFPWV was not associated with LV structure (all P≥0.27) in MAP-adjusted models). Both MAP and CFPWV were associated inversely with LV diastolic function (E'; r=-0.140 and -0.153, respectively; both P<0.0001), and these associations persisted after additional adjustment for LV mass and central pulse pressure (r=-0.142 and -0.108, both P<0.0001). MAP and CFPWV were not associated with LV fractional shortening (P≥0.10), whereas central pulse pressure was positively related (r=0.064, P<0.0001). Pulsatile and steady components of central pressure are conjointly yet variably related to LV structure. CFPWV is related to LV diastolic function but not to systolic function. Additional studies are warranted to confirm these observations. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Significance of left ventricular diastolic function on outcomes after surgical ventricular restoration.

PubMed

Marui, Akira; Nishina, Takeshi; Saji, Yoshiaki; Yamazaki, Kazuhiro; Shimamoto, Takeshi; Ikeda, Tadashi; Sakata, Ryuzo

2010-05-01

Surgical ventricular restoration (SVR) has been introduced to restore the dilated left ventricular (LV) chamber and improve LV systolic function; however, SVR has also been reported to detrimentally affect LV diastolic properties. We sought to investigate the impact of preoperative LV diastolic function on outcomes after SVR in patients with heart failure. Sixty-seven patients (60 +/- 14 years) with LV systolic dysfunction (LV ejection fraction, 0.27 +/- 0.10) underwent SVR. They were evaluated by echocardiography preoperatively, and early (

Longstanding Hyperthyroidism Is Associated with Normal or Enhanced Intrinsic Cardiomyocyte Function despite Decline in Global Cardiac Function

PubMed Central

Redetzke, Rebecca A.; Gerdes, A. Martin

2012-01-01

Thyroid hormones (THs) play a pivotal role in cardiac homeostasis. TH imbalances alter cardiac performance and ultimately cause cardiac dysfunction. Although short-term hyperthyroidism typically leads to heightened left ventricular (LV) contractility and improved hemodynamic parameters, chronic hyperthyroidism is associated with deleterious cardiac consequences including increased risk of arrhythmia, impaired cardiac reserve and exercise capacity, myocardial remodeling, and occasionally heart failure. To evaluate the long-term consequences of chronic hyperthyroidism on LV remodeling and function, we examined LV isolated myocyte function, chamber function, and whole tissue remodeling in a hamster model. Three-month-old F1b hamsters were randomized to control or 10 months TH treatment (0.1% grade I desiccated TH). LV chamber remodeling and function was assessed by echocardiography at 1, 2, 4, 6, 8, and 10 months of treatment. After 10 months, terminal cardiac function was assessed by echocardiography and LV hemodynamics. Hyperthyroid hamsters exhibited significant cardiac hypertrophy and deleterious cardiac remodeling characterized by myocyte lengthening, chamber dilatation, decreased relative wall thickness, increased wall stress, and increased LV interstitial fibrotic deposition. Importantly, hyperthyroid hamsters demonstrated significant LV systolic and diastolic dysfunction. Despite the aforementioned remodeling and global cardiac decline, individual isolated cardiac myocytes from chronically hyperthyroid hamsters had enhanced function when compared with myocytes from untreated age-matched controls. Thus, it appears that long-term hyperthyroidism may impair global LV function, at least in part by increasing interstitial ventricular fibrosis, in spite of normal or enhanced intrinsic cardiomyocyte function. PMID:23056390

Insulin resistance and subclinical abnormalities of global and regional left ventricular function in patients with aortic valve sclerosis.

PubMed

Utsunomiya, Hiroto; Yamamoto, Hideya; Kunita, Eiji; Hidaka, Takayuki; Kihara, Yasuki

2014-04-27

Insulin resistance, as a key mediator of metabolic syndrome, is thought to be associated with pathogenesis of calcific aortic valve disease and altered left ventricular (LV) function and structure. However, in patients with aortic valve sclerosis (AVS), the association between insulin resistance and subclinical impairment of LV function is not fully elucidated. We studied 57 patients (mean age 70 ± 8 years, 22 women) with asymptomatic AVS but normal LV ejection fraction in echocardiography. LV longitudinal and circumferential strain and strain rate was analyzed using two-dimensional speckle tracking echocardiography. Patients with uncontrolled hypertension and diabetes mellitus, chronic kidney disease, and concomitant coronary artery disease were excluded. They were divided into the insulin-resistant group (AVS+IR; N = 28) and no insulin-resistant group (AVS-IR; N = 29) according to the median value of homeostatic model assessment index. Computed tomography scans were also performed to measure the aortic valve calcium score and the visceral adipose tissue (VAT) area. In addition, age- and sex- adjusted 28 control subjects were recruited for the comparison. There were no significant differences in LV ejection fraction or mass index among the groups. The AVS+IR group had a higher aortic valve calcium score (median 94 versus 21, P = 0.022) and a larger VAT area (113 ± 42 cm2 versus 77 ± 38 cm2, P = 0.001) than the AVS-IR group. Notably, LV global longitudinal strain, strain rate (SR), and early diastolic SR were significantly lower in the AVS+IR group than in the AVS-IR group and in control subjects (strain: -16.2 ± 1.6% versus -17.2 ± 1.2% and -18.9 ± 0.8%; SR: -1.18 ± 0.26 s(-1) versus -1.32 ± 0.21 s(-1) and -1.52 ± 0.08 s(-1); early diastolic SR: -1.09 ± 0.23 s(-1) versus -1.23 ± 0.18 s(-1) and -1.35 ± 0.12 s(-1); P < 0.05 for all comparison), whereas circumferential function were not significantly different. Multiple linear regression analyses revealed insulin resistance as an independent determinant of LV longitudinal strain (P = 0.017), SR (P = 0.047), and early diastolic SR (P = 0.049) regardless of LV mass index or VAT area. Insulin resistance is a powerful independent predictor of subclinical LV dysfunction regardless of concomitant visceral obesity and LV hypertrophy. Thus, it may be a novel therapeutic target to prevent subsequent heart failure in patients with AVS.

Impact of Cardiac Resynchronization Therapy on Left Ventricular Mechanics: Understanding the Response through a New Quantitative Approach Based on Longitudinal Strain Integrals.

PubMed

Bernard, Anne; Donal, Erwan; Leclercq, Christophe; Schnell, Frédéric; Fournet, Maxime; Reynaud, Amélie; Thebault, Christophe; Mabo, Philippe; Daubert, J-Claude; Hernandez, Alfredo

2015-06-01

The mechanisms of improvement of left ventricular (LV) function with cardiac resynchronization therapy (CRT) are not yet elucidated. The aim of this study was to describe a new tool based on automatic quantification of the integrals of regional longitudinal strain signals and evaluate changes in LV strain distribution after CRT. This was a retrospective observational study of 130 patients with heart failure before CRT device implantation and after 3 to 6 months of follow-up. Integrals of regional longitudinal strain signals (from the beginning of the cardiac cycle to strain peak [IL,peak] and to the instant of aortic valve closure [IL,avc]) were analyzed retrospectively with custom-made algorithms. Response to CRT was defined as a decrease in LV end-systolic volume of ≥15%. Responders (61%) and nonresponders (39%) showed similar baseline values of regional IL,peak and IL,avc. At follow-up, significant improvements of midlateral IL,peak and of midlateral IL,avc were noted only in responders. Midlateral IL,avc showed a relative increase of 151 ± 276% in responders, whereas a decrease of 33 ± 69% was observed in nonresponders. The difference between IL,avc and IL,peak (representing wasted energy of the LV myocardium) of the lateral wall showed a relative change of -59 ± 103% in responders between baseline and CRT, whereas in nonresponders, the relative change was 21 ± 113% (P = .009). Strain integrals revealed changes between baseline and CRT in the lateral wall, demonstrating the beneficial effects of CRT on LV mechanics with favorable myocardial reverse remodeling. Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Resting Heart Rate as Predictor for Left Ventricular Dysfunction and Heart Failure: The Multi-Ethnic Study of Atherosclerosis

PubMed Central

Opdahl, Anders; Venkatesh, Bharath Ambale; Fernandes, Veronica R. S.; Wu, Colin O.; Nasir, Khurram; Choi, Eui-Young; Almeida, Andre L. C.; Rosen, Boaz; Carvalho, Benilton; Edvardsen, Thor; Bluemke, David A.; Lima, Joao A. C.

2014-01-01

OBJECTIVE To investigate the relationship between baseline resting heart rate and incidence of heart failure (HF) and global and regional left ventricular (LV) dysfunction. BACKGROUND The association of resting heart rate to HF and LV function is not well described in an asymptomatic multi-ethnic population. METHODS Participants in the Multi-Ethnic Study of Atherosclerosis had resting heart rate measured at inclusion. Incident HF was registered (n=176) during follow-up (median 7 years) in those who underwent cardiac MRI (n=5000). Changes in ejection fraction (ΔEF) and peak circumferential strain (Δεcc) were measured as markers of developing global and regional LV dysfunction in 1056 participants imaged at baseline and 5 years later. Time to HF (Cox model) and Δεcc and ΔEF (multiple linear regression models) were adjusted for demographics, traditional cardiovascular risk factors, calcium score, LV end-diastolic volume and mass in addition to resting heart rate. RESULTS Cox analysis demonstrated that for 1 bpm increase in resting heart rate there was a 4% greater adjusted relative risk for incident HF (Hazard Ratio: 1.04 (1.02, 1.06 (95% CI); P<0.001). Adjusted multiple regression models demonstrated that resting heart rate was positively associated with deteriorating εcc and decrease in EF, even in analyses when all coronary heart disease events were excluded from the model. CONCLUSION Elevated resting heart rate is associated with increased risk for incident HF in asymptomatic participants in MESA. Higher heart rate is related to development of regional and global LV dysfunction independent of subclinical atherosclerosis and coronary heart disease. PMID:24412444

Novel MRI-derived quantitative biomarker for cardiac function applied to classifying ischemic cardiomyopathy within a Bayesian rule learning framework

NASA Astrophysics Data System (ADS)

Menon, Prahlad G.; Morris, Lailonny; Staines, Mara; Lima, Joao; Lee, Daniel C.; Gopalakrishnan, Vanathi

2014-03-01

Characterization of regional left ventricular (LV) function may have application in prognosticating timely response and informing choice therapy in patients with ischemic cardiomyopathy. The purpose of this study is to characterize LV function through a systematic analysis of 4D (3D + time) endocardial motion over the cardiac cycle in an effort to define objective, clinically useful metrics of pathological remodeling and declining cardiac performance, using standard cardiac MRI data for two distinct patient cohorts accessed from CardiacAtlas.org: a) MESA - a cohort of asymptomatic patients; and b) DETERMINE - a cohort of symptomatic patients with a history of ischemic heart disease (IHD) or myocardial infarction. The LV endocardium was segmented and a signed phase-to-phase Hausdorff distance (HD) was computed at 3D uniformly spaced points tracked on segmented endocardial surface contours, over the cardiac cycle. An LV-averaged index of phase-to-phase endocardial displacement (P2PD) time-histories was computed at each tracked point, using the HD computed between consecutive cardiac phases. Average and standard deviation in P2PD over the cardiac cycle was used to prepare characteristic curves for the asymptomatic and IHD cohort. A novel biomarker of RMS error between mean patient-specific characteristic P2PD over the cardiac cycle for each individual patient and the cumulative P2PD characteristic of a cohort of asymptomatic patients was established as the RMS-P2PD marker. The novel RMS-P2PD marker was tested as a cardiac function based feature for automatic patient classification using a Bayesian Rule Learning (BRL) framework. The RMS-P2PD biomarker indices were significantly different for the symptomatic patient and asymptomatic control cohorts (p<0.001). BRL accurately classified 83.8% of patients correctly from the patient and control populations, with leave-one-out cross validation, using standard indices of LV ejection fraction (LV-EF) and LV end-systolic volume index (LV-ESVI). This improved to 91.9% with inclusion of the RMS-P2PD biomarker and was congruent with improvements in both sensitivity for classifying patients and specificity for identifying asymptomatic controls from 82.6% up to 95.7%. RMS-P2PD, when contrasted against a collective normal reference, is a promising biomarker to investigate further in its utility for identifying quantitative signs of pathological endocardial function which may boost standard image makers as precursors of declining cardiac performance.

Correlation of transforming growth factor-β1 and tumour necrosis factor levels with left ventricular function in Chagas disease

PubMed Central

Curvo, Eduardo OV; Ferreira, Roberto R; Madeira, Fabiana S; Alves, Gabriel F; Chambela, Mayara C; Mendes, Veronica G; Sangenis, Luiz Henrique C; Waghabi, Mariana C; Saraiva, Roberto M

2018-01-01

BACKGROUND Transforming growth factor β1 (TGF-β1) and tumour necrosis factor (TNF) have been implicated in Chagas disease pathophysiology and may correlate with left ventricular (LV) function. OBJECTIVES We determined whether TGF-β1 and TNF serum levels correlate with LV systolic and diastolic functions and brain natriuretic peptide (BNP) serum levels in chronic Chagas disease. METHODS This cross-sectional study included 152 patients with Chagas disease (43% men; 57 ± 12 years old), classified as 53 patients with indeterminate form and 99 patients with cardiac form (stage A: 24, stage B: 25, stage C: 44, stage D: 6). TGF-β1, TNF, and BNP were determined by enzyme-linked immunosorbent assay ELISA. Echocardiogram was used to determine left atrial and LV diameters, as well as LV ejection fraction and diastolic function. FINDINGS TGF-b1 serum levels were lower in stages B, C, and D, while TNF serum levels were higher in stages C and D of the cardiac form. TGF-β1 presented a weak correlation with LV diastolic function and LV ejection fraction. TNF presented a weak correlation with left atrial and LV diameters and LV ejection fraction. CONCLUSIONS TNF is increased, while TGF-β1 is decreased in the cardiac form of chronic Chagas disease. TNF and TGF-β1 serum levels present a weak correlation with LV systolic and diastolic function in Chagas disease patients. PMID:29513876

Diastolic dysfunction is associated with insulin resistance, but not with aldosterone level in normotensive offspring of hypertensive families.

PubMed

Zizek, Bogomir; Poredos, Pavel; Trojar, Andrej; Zeljko, Tadej

2008-01-01

We investigated left ventricular (LV) morphology and function in association with insulin level/insulin resistance (IR) and aldosterone level in normotensive offspring of subjects with essential hypertension (familial trait, FT). The study encompassed 76 volunteers of whom 44 were normotensive with FT (aged 28-39 years) and 32 age-matched controls without FT. LV mass and function were measured using conventional echocardiography and tissue Doppler imaging. LV diastolic function was reported as peak septal annular velocities (E(m) and E(m)/A(m) ratio) in tissue Doppler imaging. Fasting insulin and aldosterone were determined. In subjects with FT, the LV mass was higher than in controls (92.14 +/- 24.02 vs. 70.08 +/- 20.58 g; p < 0.001). The study group had a worse LV diastolic function than control subjects (lower E(m) and E(m)/A(m) ratio; p < 0.001). In subjects with FT, the E(m)/A(m) ratio was independently associated with IR (partial p = 0.029 in multivariate model, R(2) = 0.51), but not with LV mass. The aldosterone level was comparable in both groups. In normotensive individuals with FT, LV morphological and functional abnormalities were found. LV dysfunction but not an increase in LV mass is associated with IR. The aldosterone level is probably not responsible for the development of early hypertensive heart disease. (c) 2008 S. Karger AG, Basel.

Worsening of left ventricular end-systolic volume and mitral regurgitation without increase in left ventricular dyssynchrony on acute interruption of cardiac resynchronization therapy.

PubMed

Kuppahally, Suman S; Fowler, Michael B; Vagelos, Randall; Wang, Paul; Al-Ahmad, Amin; Paloma, Allan; Liang, David

2009-08-01

Responders to cardiac resynchronization therapy (CRT) have greater left ventricular (LV) dyssynchrony than nonresponders prior to CRT. We conducted this study to see whether the long term responders have more worsening of LV dyssynchrony and LV function on acute interruption of CRT. We identified 22 responders and 13 nonresponders who received CRT as per standard criteria for 23.73 +/- 7.9 months (median 24.5 months). We assessed the acute change in LV function, mitral regurgitation (MR) and compared LV dyssynchrony in CRT on and off modes. On turning off CRT, there was no significant worsening of LV dyssynchrony in both responders and nonresponders. The dyssynchrony measurements by SPWMD, TDI and 3D echocardiography did not correlate significantly. LVESV increased (p = 0.02) and MR (p = 0.01) worsened in CRT-off mode in responders only without significant change in LVEF or LV dimensions. In long-term responders to CRT, there is alteration in the function of remodeled LV with acute interruption of CRT, without significant worsening of LV dyssynchrony. The role of different echocardiographic parameters in the assessment of LV dyssynchrony remains controversial. Even after long-term CRT reversely remodels the LV, the therapy needs to be continued uninterrupted for sustained benefits.

Identifying the function of LvPI3K during the pathogenic infection of Litopenaeus vannamei by Vibrio alginolyticus.

PubMed

Kong, Jing-Rong; Wei, Wei; Liang, Qing-Jian; Qiao, Xue-Li; Kang, Huan; Liu, Yuan; Wang, Wei-Na

2018-05-01

It is well known that PI3K regulates various processes in mammalian cells by generating a secondary messenger that later activates AKT. However, its innate immune function in crustaceans remains unclear. We report the characterization of Litopenaeus vannamei PI3K (LvPI3K) for investigating how PI3K participates in the innate immunity of crustaceans. Full-length LvPI3K cDNA was 3357 bp long, with a 3222 bp open reading frame (ORF) that encodes a putative protein of 1292 amino acids. The PI3K catalytic domain (PI3Kc) of LvPI3K was found to be rather conserved when the PI3Ks from other species were analyzed. The LvPI3K protein was shown to be localized to the cytoplasm of Drosophila S2 cells, while LvPI3K mRNA was ubiquitously expressed in healthy L. vannamei, with the highest expression found in hemolymph. A dual luciferase reporter gene assay demonstrated that LvPI3K overexpression activated the promoter of antibacterial peptide LvPEN4 in a dose-dependent manner. However, the addition of PDTC, a specific inhibitor of NF-κB, suppressed the LvPI3K-induced LvPEN4 promoter activation. Moreover, Vibrio alginolyticus challenge induced a rapid up-regulation of LvPI3K expression. Further experiments showed that LvPI3K silencing in shrimp challenged with V. alginolyticus significantly increased Vibrio number, ROS production and DNA damage in the hemolymph, as well as significantly decreased total hemocyte count. The mRNA levels of certain molecules related to LvPI3K signaling, such as LvAKT and LvPEN4, also decreased following LvPI3K silencing. Taken together, these results suggest that LvPI3K regulates the downstream signal component LvPEN4 and functions in V. alginolyticus resistance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Left ventricular function quantified by myocardial strain imaging in small-breed dogs with chronic mitral regurgitation.

PubMed

Smith, Danielle N; Bonagura, John D; Culwell, Nicole M; Schober, Karsten E

2012-03-01

The presence of left ventricular (LV) systolic dysfunction may influence prognosis or therapy in dogs with chronic mitral regurgitation (MR). Assessment of LV function in MR by conventional echocardiography is confounded by altered ventricular loading. Myocardial deformation (strain) imaging might offer more sensitive estimates of LV function in this disease. Prospectively measure myocardial strain in dogs with asymptomatic MR compared to a control group. Forty healthy dogs (3.5-11.5 kg): 20 Controls; 20 dogs with MR and LV remodeling (Stage B2), were evaluated in this study. LV size and function were assessed in a short-axis plane. Segmental radial strain and strain rate and global circumferential strain were measured using a 2D echocardiographic speckle-tracking algorithm (GE EchoPAC). Groups were compared using Bonferroni t-tests. Influences of heart rate and body weight were explored with linear regression. The MR group had significantly greater mean values for heart rate, LV size, and LV systolic function. Specifically, LV diastolic diameter, diastole area, shortening fraction, averaged peak systolic and early diastolic radial strain, global circumferential strain, and averaged radial strain rate were significantly greater in the MR group (p < 0.015 to p < 0.001). Strain was unrelated to weight, but weakly correlated with heart rate. Similar to conventional indices, Stage B2 dogs with MR demonstrate hyperdynamic deformation in the short-axis plane. Short-axis strain variables measured by 2D speckle tracking are greater than for controls of similar age and weight. These results imply either preserved LV systolic function or that LV dysfunction is masked by altered ventricular loading. Copyright © 2012 Elsevier B.V. All rights reserved.

The effect of geographical indices on left ventricular structure in healthy Han Chinese population

NASA Astrophysics Data System (ADS)

Cen, Minyi; Ge, Miao; Liu, Yonglin; Wang, Congxia; Yang, Shaofang

2017-02-01

The left ventricular posterior wall thickness (LVPWT) and interventricular septum thickness (IVST) are generally regarded as the functional parts of the left ventricular (LV) structure. This paper aims to examine the effects of geographical indices on healthy Han adults' LV structural indices and to offer a scientific basis for developing a unified standard for the reference values of adults' LV structural indices in China. Fifteen terrain, climate, and soil indices were examined as geographical explanatory variables. Statistical analysis was performed using correlation analysis. Moreover, a back propagation neural network (BPNN) and a support vector regression (SVR) were applied to developing models to predict the values of two indices. After the prediction models were built, distribution maps were produced. The results show that LV structural indices are characteristically associated with latitude, longitude, altitude, average temperature, average wind velocity, topsoil sand fraction, topsoil silt fraction, topsoil organic carbon, and topsoil sodicity. The model test analyses show the BPNN model possesses better simulative and predictive ability in comparison with the SVR model. The distribution maps of the LV structural indices show that, in China, the values are higher in the west and lower in the east. These results demonstrate that the reference values of the adults' LV structural indices will be different affected by different geographical environment. The reference values of LV structural indices in one region can be calculated by setting up a BPNN, which showed better applicability in this study. The distribution of the reference values of the LV structural indices can be seen clearly on the geographical distribution map.

The effect of geographical indices on left ventricular structure in healthy Han Chinese population.

PubMed

Cen, Minyi; Ge, Miao; Liu, Yonglin; Wang, Congxia; Yang, Shaofang

2017-02-01

The left ventricular posterior wall thickness (LVPWT) and interventricular septum thickness (IVST) are generally regarded as the functional parts of the left ventricular (LV) structure. This paper aims to examine the effects of geographical indices on healthy Han adults' LV structural indices and to offer a scientific basis for developing a unified standard for the reference values of adults' LV structural indices in China. Fifteen terrain, climate, and soil indices were examined as geographical explanatory variables. Statistical analysis was performed using correlation analysis. Moreover, a back propagation neural network (BPNN) and a support vector regression (SVR) were applied to developing models to predict the values of two indices. After the prediction models were built, distribution maps were produced. The results show that LV structural indices are characteristically associated with latitude, longitude, altitude, average temperature, average wind velocity, topsoil sand fraction, topsoil silt fraction, topsoil organic carbon, and topsoil sodicity. The model test analyses show the BPNN model possesses better simulative and predictive ability in comparison with the SVR model. The distribution maps of the LV structural indices show that, in China, the values are higher in the west and lower in the east. These results demonstrate that the reference values of the adults' LV structural indices will be different affected by different geographical environment. The reference values of LV structural indices in one region can be calculated by setting up a BPNN, which showed better applicability in this study. The distribution of the reference values of the LV structural indices can be seen clearly on the geographical distribution map.

Different brain activation under left and right ventricular stimulation: an fMRI study in anesthetized rats.

PubMed

Suzuki, Hideaki; Sumiyoshi, Akira; Kawashima, Ryuta; Shimokawa, Hiroaki

2013-01-01

Myocardial ischemia in the anterior wall of the left ventricule (LV) and in the inferior wall and/or right ventricle (RV) shows different manifestations that can be explained by the different innervations of cardiac afferent nerves. However, it remains unclear whether information from different areas of the heart, such as the LV and RV, are differently processed in the brain. In this study, we investigated the brain regions that process information from the LV or RV using cardiac electrical stimulation and functional magnetic resonance imaging (fMRI) in anesthetized rats because the combination of these two approaches cannot be used in humans. An electrical stimulation catheter was inserted into the LV or RV (n = 12 each). Brain fMRI scans were recorded during LV or RV stimulation (9 Hz and 0.3 ms width) over 10 blocks consisting of alternating periods of 2 mA for 30 sec followed by 0.2 mA for 60 sec. The validity of fMRI signals was confirmed by first and second-level analyses and temporal profiles. Increases in fMRI signals were observed in the anterior cingulate cortex and the right somatosensory cortex under LV stimulation. In contrast, RV stimulation activated the right somatosensory cortex, which was identified more anteriorly compared with LV stimulation but did not activate the anterior cingulate cortex. This study provides the first evidence for differences in brain activation under LV and RV stimulation. These different brain processes may be associated with different clinical manifestations between anterior wall and inferoposterior wall and/or RV myocardial ischemia.

Insulin resistance-associated decreases in left ventricular diastolic function are strongly modified by the extent of concentric remodeling in a community sample.

PubMed

Peterson, Vernice; Norton, Gavin R; Raymond, Andrew; Libhaber, Carlos D; Millen, Aletta M E; Majane, Olebogeng H I; Maseko, Muzi J; Woodiwiss, Angela J

2016-10-01

Whether excess adiposity, associated metabolic abnormalities or alternative risk factors for left ventricular (LV) diastolic function are modified rather than mediated by geometric LV remodeling, is uncertain. Echocardiographic LV mass index (LVMI), relative wall thickness (RWT) and diastolic function (lateral and septal wall myocardial tissue lengthening at the level of the mitral annulus [e'] [n=430], ratio of early-to-late transmitral blood flow velocity (E/A), and E/e' [n=430]) were determined in 737 randomly recruited participants of a community-based study (43% obese). Independent of LVMI and confounders, indexes of adiposity and the homeostasis model of insulin resistance (HOMA-IR) were independently associated with LV diastolic function (p<0.05). In addition, RWT was independently associated with LV diastolic function (p<0.002). Importantly, an independent interaction between HOMA-IR and RWT, but not between blood pressure or age and RWT, was related to LV diastolic function (p<0.05). This translated into an independent relationship between HOMA-IR and lateral e' (partial r=-0.17, p<0.02), septal e' (partial r=-0.14, p=0.05), E/A (partial r=-0.17, p<0.005) and E/e' (partial r=0.19, p<0.01) in those with RWT above, but a lack of relationship between HOMA-IR and LV diastolic function (p>0.59) in those with RWT below the median for the sample. Similarly, HOMA-IR was independently associated with LV diastolic dysfunction in those with RWT above (p<0.05) but not below (p>0.19) the median for the sample. The relationship between insulin resistance, but not alternative risk factors and LV diastolic function is markedly modified by the presence of a more concentrically remodeled LV. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Unique crystal structure of a novel surfactant protein from the foam nest of the frog Leptodactylus vastus.

PubMed

Cavalcante Hissa, Denise; Arruda Bezerra, Gustavo; Birner-Gruenberger, Ruth; Paulino Silva, Luciano; Usón, Isabel; Gruber, Karl; Maciel Melo, Vânia Maria

2014-02-10

Breeding by releasing eggs into stable biofoams ("foam nests") is a peculiar reproduction mode within anurans, fish, and tunicates; not much is known regarding the biochemistry or molecular mechanisms involved. Lv-ranaspumin (Lv-RSN-1) is the predominant protein from the foam nest of the frog Leptodactylus vastus. This protein shows natural surfactant activity, which is assumed to be crucial for stabilizing foam nests. We elucidated the amino acid sequence of Lv-RSN-1 by de novo sequencing with mass-spectrometry and determined the high-resolution X-ray structure of the protein. It has a unique fold mainly composed of a bundle of 11 α-helices and two small antiparallel β-strands. Lv-RSN-1 has a surface rich in hydrophilic residues and a lipophilic cavity in the region of the antiparallel β-sheet. It possesses intrinsic surface-active properties, reducing the surface tension of water from 73 to 61 mN m(-1) (15 μg mL(-1)). Lv-RSN-1 belongs to a new class of surfactants proteins for which little has been reported regarding structure or function. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Autologous CD133+ bone marrow cells and bypass grafting for regeneration of ischaemic myocardium: the Cardio133 trial.

PubMed

Nasseri, Boris A; Ebell, Wolfram; Dandel, Michael; Kukucka, Marian; Gebker, Rolf; Doltra, Adelina; Knosalla, Christoph; Choi, Yeong-Hoon; Hetzer, Roland; Stamm, Christof

2014-05-14

Intra-myocardial transplantation of CD133(+) bone marrow stem cells (BMC) yielded promising results in clinical pilot trials. We now performed the double-blinded, randomized, placebo-controlled CARDIO133 trial to determine its impact on left ventricular (LV) function and clinical symptoms. Sixty patients with chronic ischaemic heart disease and impaired LV function (left ventricular ejection fraction, LVEF <35%) were randomized to undergo either coronary artery bypass grafting (CABG) and injection of CD133(+) BMC in the non-transmural, hypokinetic infarct border zone (CD133), or CABG and placebo injection (placebo). Pre-operative LVEF was 27 ± 6% in CD133 patients and 26 ± 6% in placebo patients. Outcome was assessed after 6 months, and the primary endpoint was LVEF measured by cardiac magnetic resonance imaging (MRI) at rest. The incidence of adverse events was similar in both groups. There was no difference in 6-min walking distance, Minnesota Living with Heart Failure score, or Canadian Cardiovascular Society (CCS) class between groups at follow-up, and New York Heart Association class improved more in the placebo group (P = 0.004). By cardiac MRI, LVEF at 6 months was 33 ± 8% in the placebo group and 31 ± 7% in verum patients (P = 0.3), with an average inter-group difference of -2.1% (95% CI -6.3 to 2.1). Systolic or diastolic LV dimensions at 6 months were not different, either. In the CD133 group, myocardial perfusion at rest recovered in more LV segments than in the placebo group (9 vs. 2%, P < 0.001). Scar mass decreased by 2.2 ± 5 g in CD133(+) patients (P = 0.05), but was unchanged in the placebo group (0.3 ± 4 g, P = 0.7; inter-group difference in change = 2 g (95% CI -1.1 to 5)). By speckle-tracking echocardiography, cell-treated patients showed a better recovery of regional wall motion when the target area was posterior. Although there may be some improvements in scar size and regional perfusion, intra-myocardial injection of CD133(+) BMC has no effect on global LV function and clinical symptoms. Improvements in regional myocardial function are only detectable in patients with posterior infarction, probably because the interventricular septum after anterior infarction is not accessible by trans-epicardial injection. This trial was registered at http://www.clinicaltrials.gov under NCT00462774. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Changes in left atrial deformation in hypertrophic cardiomyopathy: Evaluation by vector velocity imaging

PubMed Central

Badran, Hala Mahfouz; Soltan, Ghada; Hassan, Hesham; Nazmy, Ahmed; Faheem, Naglaa; Saadan, Haythem; Yacoub, Magdi H.

2012-01-01

Abstract: Objectives: Hypertrophic cardiomyopathy (HCM) represents a generalized myopathic process affecting both ventricular and atrial myocardium. We assessed the global and regional left atrial (LA) function and its relation to left ventricular (LV) mechanics and clinical status in patients with HCM using Vector Velocity Imaging (VVI). Methods: VVI of the LA and LV was acquired from apical four- and two-chamber views of 108 HCM patients (age 40 ± 19years, 56.5% men) and 33 healthy subjects, all had normal LV systolic function. The LA subendocardium was traced to obtain atrial volumes, ejection fraction, velocities, and strain (ϵ)/strain rate (SR) measurements. Results: Left atrial reservoir (ϵsys,SRsys) and conduit (early diastolic SRe) function were significantly reduced in HCM compared to controls (P < .0001). Left atrial deformation directly correlated to LVϵsys, SRsys and negatively correlated to age, NYHA class, left ventricular outflow tract (LVOT) gradient, left ventricular mass index (LVMI), LA volume index and severity of mitral regurge (P < 0.001). Receiver operating characterist was constructed to explore the cutoff value of LA deformation in differentiation of LA dysfunction; ϵsys < 40% was 75% sensitive, 50% specific, SRsys < 1.7s− 1 was 70% sensitive, 61% specific, SRe> − 1.8s− 1 was 81% sensitive and 30% specific, SRa> − 1.5s− 1 was 73% sensitive and 40% specific. By multivariate analysis global LVϵsys and LV septal thickness are independent predictors for LAϵsys, while end systolic diameter is the only independent predictor for SRsys, P < .001. Conclusion: Left atrial reservoir and conduit function as measured by VVI were significantly impaired while contractile function was preserved among HCM patients. Left atrial deformation was greatly influenced by LV mechanics and correlated to severity of phenotype. PMID:24688992

Preemptive heme oxygenase-1 gene delivery reveals reduced mortality and preservation of left ventricular function 1 yr after acute myocardial infarction.

PubMed

Liu, Xiaoli; Simpson, Jeremy A; Brunt, Keith R; Ward, Christopher A; Hall, Sean R R; Kinobe, Robert T; Barrette, Valerie; Tse, M Yat; Pang, Stephen C; Pachori, Alok S; Dzau, Victor J; Ogunyankin, Kofo O; Melo, Luis G

2007-07-01

We reported previously that predelivery of heme oxygenase-1 (HO-1) gene to the heart by adeno-associated virus-2 (AAV-2) markedly reduces ischemia and reperfusion (I/R)-induced myocardial injury. However, the effect of preemptive HO-1 gene delivery on long-term survival and prevention of postinfarction heart failure has not been determined. We assessed the effect of HO-1 gene delivery on long-term survival, myocardial function, and left ventricular (LV) remodeling 1 yr after myocardial infarction (MI) using echocardiographic imaging, pressure-volume (PV) analysis, and histomorphometric approaches. Two groups of Lewis rats were injected with 2 x 10(11) particles of AAV-LacZ (control) or AAV-human HO-1 (hHO-1) in the anterior-posterior apical region of the LV wall. Six weeks after gene transfer, animals were subjected to 30 min of ischemia by ligation of the left anterior descending artery followed by reperfusion. Echocardiographic measurements and PV analysis of LV function were obtained at 2 wk and 12 mo after I/R. One year after acute MI, mortality was markedly reduced in the HO-1-treated animals compared with the LacZ-treated animals. PV analysis demonstrated significantly enhanced LV developed pressure, elevated maximal dP/dt, and lower end-diastolic volume in the HO-1 animals compared with the LacZ animals. Echocardiography showed a larger apical anterior-to-posterior wall ratio in HO-1 animals compared with LacZ animals. Morphometric analysis revealed extensive myocardial scarring and fibrosis in the infarcted LV area of LacZ animals, which was reduced by 62% in HO-1 animals. These results suggest that preemptive HO-1 gene delivery may be useful as a therapeutic strategy to reduce post-MI LV remodeling and heart failure.

Mast cell stabilization decreases cardiomyocyte and LV function in dogs with isolated mitral regurgitation.

PubMed

Pat, Betty; Killingsworth, Cheryl; Chen, Yuanwen; Gladden, James D; Walcott, Greg; Powell, Pamela C; Denney, Thomas; Gupta, Himanshu; Desai, Ravi; Tillson, Michael; Dillon, A Ray; Dell'italia, Louis J

2010-09-01

Mast cells are increased in isolated mitral regurgitation (MR) in the dog and may mediate extracellular matrix loss and left ventricular (LV) dilatation. We tested the hypothesis that mast cell stabilization would attenuate LV remodeling and improve function in the MR dog. MR was induced in adult dogs randomized to no treatment (MR, n = 5) or to the mast cell stabilizer, ketotifen (MR + MCS, n = 4) for 4 months. LV hemodynamics were obtained at baseline and after 4 months of MR and magnetic resonance imaging (MRI) was performed at sacrifice. MRI-derived, serial, short-axis LV end-diastolic (ED) and end-systolic (ES) volumes, LVED volume/mass ratio, and LV 3-dimensional radius/wall thickness were increased in MR and MR + MCS dogs compared with normal dogs (n = 6) (P < .05). Interstitial collagen was decreased by 30% in both MR and MR + MCS versus normal dogs (P < .05). LV contractility by LV maximum time-varying elastance was significantly depressed in MR and MR + MCS dogs. Furthermore, cardiomyocyte fractional shortening was decreased in MR versus normal dogs and further depressed in MR + MCS dogs (P < .05). In vitro administration of ketotifen to normal cardiomyocytes also significantly decreased fractional shortening and calcium transients. Chronic mast cell stabilization did not attenuate eccentric LV remodeling or collagen loss in MR. However, MCS therapy had a detrimental effect on LV function because of a direct negative inotropic effect on cardiomyocyte function. Published by Elsevier Inc.

Gender Differences in Left Ventricular Function Following Percutaneous Coronary Intervention for First Anterior Wall ST-Segment Elevation Myocardial Infarction.

PubMed

Weissler-Snir, Adaya; Kornowski, Ran; Sagie, Alexander; Vaknin-Assa, Hana; Perl, Leor; Porter, Avital; Lev, Eli; Assali, Abid

2014-11-15

Little is known regarding gender differences in left ventricular (LV) function after anterior wall ST-segment elevation myocardial infarction (STEMI), despite it being a major determinant of patients' morbidity and mortality. We therefore sought to investigate the impact of gender on LV function after primary percutaneous coronary intervention (PCI) for first anterior wall STEMI. Seven hundred eighty-nine consecutive patients (625 men) with first anterior STEMI were included in the analysis. All patients underwent an echocardiographic study within 48 hours of PCI. Women were older and more likely to have diabetes, hypertension, chronic renal failure, and a higher Killip score. Women had prolonged ischemic time, which was driven by prolonged symptom-to-presentation time (2.75 [interquartile range 1.5 to 4] vs 2 [interquartile range 1 to 3.5] hours, p = 0.005). A higher percentage of women had moderate or worse LV dysfunction (LV ejection fraction <40%; 61.6% vs 48%, p = 0.002). In a univariable analysis female gender was associated with moderate or worse LV function (p = 0.002). However, after accounting for variable baseline risk profiles between the 2 groups using multivariable and propensity score techniques, ischemic time >3.5 hours, leukocytosis, and pre-PCI Thrombolysis In Myocardial Infarction flow grade <2 were independent predictors of moderate or worse LV dysfunction, whereas female gender was not. Data on LV function recovery at 6 months, which were available for 45% of female and male patients with moderate or worse LV dysfunction early after PCI, showed no significant gender related difference in LV function recovery. In conclusion, women undergoing PCI for the first event of anterior STEMI demonstrate worse LV function than that of men, which might be partially attributed to delay in presentation. Hence greater efforts should be devoted to increasing women's awareness of cardiac symptoms during the prehospital course of STEMI. Copyright © 2014 Elsevier Inc. All rights reserved.

Alterations in left ventricular diastolic function in conscious dogs with pacing-induced heart failure

NASA Technical Reports Server (NTRS)

Komamura, K.; Shannon, R. P.; Pasipoularides, A.; Ihara, T.; Lader, A. S.; Patrick, T. A.; Bishop, S. P.; Vatner, S. F.

1992-01-01

We investigated in conscious dogs (a) the effects of heart failure induced by chronic rapid ventricular pacing on the sequence of development of left ventricular (LV) diastolic versus systolic dysfunction and (b) whether the changes were load dependent or secondary to alterations in structure. LV systolic and diastolic dysfunction were evident within 24 h after initiation of pacing and occurred in parallel over 3 wk. LV systolic function was reduced at 3 wk, i.e., peak LV dP/dt fell by -1,327 +/- 105 mmHg/s and ejection fraction by -22 +/- 2%. LV diastolic dysfunction also progressed over 3 wk of pacing, i.e., tau increased by +14.0 +/- 2.8 ms and the myocardial stiffness constant by +6.5 +/- 1.4, whereas LV chamber stiffness did not change. These alterations were associated with increases in LV end-systolic (+28.6 +/- 5.7 g/cm2) and LV end-diastolic stresses (+40.4 +/- 5.3 g/cm2). When stresses and heart rate were matched at the same levels in the control and failure states, the increases in tau and myocardial stiffness were no longer observed, whereas LV systolic function remained depressed. There were no increases in connective tissue content in heart failure. Thus, pacing-induced heart failure in conscious dogs is characterized by major alterations in diastolic function which are reversible with normalization of increased loading condition.

Early Left and Right Ventricular Response to Aortic Valve Replacement.

PubMed

Duncan, Andra E; Sarwar, Sheryar; Kateby Kashy, Babak; Sonny, Abraham; Sale, Shiva; Alfirevic, Andrej; Yang, Dongsheng; Thomas, James D; Gillinov, Marc; Sessler, Daniel I

2017-02-01

The immediate effect of aortic valve replacement (AVR) for aortic stenosis on perioperative myocardial function is unclear. Left ventricular (LV) function may be impaired by cardioplegia-induced myocardial arrest and ischemia-reperfusion injury, especially in patients with LV hypertrophy. Alternatively, LV function may improve when afterload is reduced after AVR. The right ventricle (RV), however, experiences cardioplegic arrest without benefiting from improved loading conditions. Which of these effects on myocardial function dominate in patients undergoing AVR for aortic stenosis has not been thoroughly explored. Our primary objective is thus to characterize the effect of intraoperative events on LV function during AVR using echocardiographic measures of myocardial deformation. Second, we evaluated RV function. In this supplementary analysis of 100 patients enrolled in a clinical trial (NCT01187329), 97 patients underwent AVR for aortic stenosis. Of these patients, 95 had a standardized intraoperative transesophageal echocardiographic examination of systolic and diastolic function performed before surgical incision and repeated after chest closure. Echocardiographic images were analyzed off-line for global longitudinal myocardial strain and strain rate using 2D speckle-tracking echocardiography. Myocardial deformation assessed at the beginning of surgery was compared with the end of surgery using paired t tests corrected for multiple comparisons. LV volumes and arterial blood pressure decreased, and heart rate increased at the end of surgery. Echocardiographic images were acceptable for analysis in 72 patients for LV strain, 67 for LV strain rate, and 54 for RV strain and strain rate. In 72 patients with LV strain images, 9 patients required epinephrine, 22 required norepinephrine, and 2 required both at the end of surgery. LV strain did not change at the end of surgery compared with the beginning of surgery (difference: 0.7 [97.6% confidence interval, -0.2 to 1.5]%; P = 0.07), whereas LV systolic strain rate improved (became more negative) (-0.3 [-0.4 to -0.2] s; P < 0.001). In contrast, RV systolic strain worsened (became less negative) at the end of surgery (difference: 4.6 [3.1 to 6.0]%; P < 0.001) although RV systolic strain rate was unchanged (0.0 [97.6% confidence interval, -0.1 to 0.1]; P = 0.83). LV function improved after replacement of a stenotic aortic valve demonstrated by improved longitudinal strain rate. In contrast, RV function, assessed by longitudinal strain, was reduced.

Ectopic fat depots and left ventricular function in nondiabetic men with nonalcoholic fatty liver disease.

PubMed

Granér, Marit; Nyman, Kristofer; Siren, Reijo; Pentikäinen, Markku O; Lundbom, Jesper; Hakkarainen, Antti; Lauerma, Kirsi; Lundbom, Nina; Nieminen, Markku S; Taskinen, Marja-Riitta

2015-01-01

Nonalcoholic fatty liver disease has emerged as a novel cardiovascular risk factor. The aim of the study was to assess the effect of different ectopic fat depots on left ventricular (LV) function in subjects with nonalcoholic fatty liver disease. Myocardial and hepatic triglyceride contents were measured with 1.5 T magnetic resonance spectroscopy and LV function, visceral adipose tissue (VAT) and subcutaneous adipose tissue, epicardial and pericardial fat by MRI in 75 nondiabetic men. Subjects were stratified by hepatic triglyceride content into low, moderate, and high liver fat groups. Myocardial triglyceride, epicardial and pericardial fat, VAT, and subcutaneous adipose tissue increased stepwise from low to high liver fat group. Parameters of LV diastolic function showed a stepwise decrease over tertiles of liver fat and VAT, and they were inversely correlated with hepatic triglyceride, VAT, and VAT/subcutaneous adipose tissue ratio. In multivariable analyses, hepatic triglyceride and VAT were independent predictors of LV diastolic function, whereas myocardial triglyceride was not associated with measures of diastolic function. Myocardial triglyceride, epicardial and pericardial fat increased with increasing amount of liver fat and VAT. Hepatic steatosis and VAT associated with significant changes in LV structure and function. The association of LV diastolic function with hepatic triglyceride and VAT may be because of toxic systemic effects. The effects of myocardial triglyceride on LV structure and function seem to be more complex than previously thought and merit further study. © 2014 American Heart Association, Inc.

Insulin resistance and subclinical abnormalities of global and regional left ventricular function in patients with aortic valve sclerosis

PubMed Central

2014-01-01

Background Insulin resistance, as a key mediator of metabolic syndrome, is thought to be associated with pathogenesis of calcific aortic valve disease and altered left ventricular (LV) function and structure. However, in patients with aortic valve sclerosis (AVS), the association between insulin resistance and subclinical impairment of LV function is not fully elucidated. Methods We studied 57 patients (mean age 70 ± 8 years, 22 women) with asymptomatic AVS but normal LV ejection fraction in echocardiography. LV longitudinal and circumferential strain and strain rate was analyzed using two-dimensional speckle tracking echocardiography. Patients with uncontrolled hypertension and diabetes mellitus, chronic kidney disease, and concomitant coronary artery disease were excluded. They were divided into the insulin-resistant group (AVS+IR; N = 28) and no insulin-resistant group (AVS-IR; N = 29) according to the median value of homeostatic model assessment index. Computed tomography scans were also performed to measure the aortic valve calcium score and the visceral adipose tissue (VAT) area. In addition, age- and sex- adjusted 28 control subjects were recruited for the comparison. Results There were no significant differences in LV ejection fraction or mass index among the groups. The AVS+IR group had a higher aortic valve calcium score (median 94 versus 21, P = 0.022) and a larger VAT area (113 ± 42 cm2 versus 77 ± 38 cm2, P = 0.001) than the AVS-IR group. Notably, LV global longitudinal strain, strain rate (SR), and early diastolic SR were significantly lower in the AVS+IR group than in the AVS-IR group and in control subjects (strain: -16.2 ± 1.6% versus -17.2 ± 1.2% and -18.9 ± 0.8%; SR: -1.18 ± 0.26 s-1 versus -1.32 ± 0.21 s-1 and -1.52 ± 0.08 s-1; early diastolic SR: -1.09 ± 0.23 s-1 versus -1.23 ± 0.18 s-1 and -1.35 ± 0.12 s-1; P < 0.05 for all comparison), whereas circumferential function were not significantly different. Multiple linear regression analyses revealed insulin resistance as an independent determinant of LV longitudinal strain (P = 0.017), SR (P = 0.047), and early diastolic SR (P = 0.049) regardless of LV mass index or VAT area. Conclusions Insulin resistance is a powerful independent predictor of subclinical LV dysfunction regardless of concomitant visceral obesity and LV hypertrophy. Thus, it may be a novel therapeutic target to prevent subsequent heart failure in patients with AVS. PMID:24767168

Changes in Left Ventricular Morphology and Function After Mitral Valve Surgery

PubMed Central

Shafii, Alexis E.; Gillinov, A. Marc; Mihaljevic, Tomislav; Stewart, William; Batizy, Lillian H.; Blackstone, Eugene H.

2015-01-01

Degenerative mitral valve disease is the leading cause of mitral regurgitation in North America. Surgical intervention has hinged on symptoms and ventricular changes that develop as compensatory ventricular remodeling takes place. In this study, we sought to characterize the temporal response of left ventricular (LV) morphology and function to mitral valve surgery for degenerative disease, and identify preoperative factors that influence reverse remodeling. From 1986–2007, 2,778 patients with isolated degenerative mitral valve disease underwent valve repair (n=2,607/94%) or replacement (n=171/6%) and had at least 1 postoperative transthoracic echocardiogram (TTE); 5,336 TTEs were available for analysis. Multivariable longitudinal repeated-measures analysis was performed to identify factors associated with reverse remodeling. LV dimensions decreased in the first year after surgery (end-diastolic from 5.7±0.80 to 4.9±1.4 cm; end-systolic from 3.4±0.71 to 3.1±1.4 cm). LV mass index decreased from 139±44 to 112±73 g·m−2. Reduction of LV hypertrophy was less pronounced in patients with greater preoperative left heart enlargement (P<.0001) and greater preoperative LV mass (P<.0001). Postoperative LV ejection fraction initially decreased from 58±7.0 to 53±20, increased slightly over the first postoperative year, and was negatively influenced by preoperative heart failure symptoms (P<.0001) and lower preoperative LV ejection fraction (P<.0001). Risk-adjusted response of LV morphology and function to valve repair and replacement was similar (P>.2). In conclusion, a positive response toward normalization of LV morphology and function after mitral valve surgery is greatest in the first year. The best response occurs when surgery is performed before left heart dilatation, LV hypertrophy, or LV dysfunction develop. PMID:22534055

Improved recovery of regional left ventricular function after PCI of chronic total occlusion in STEMI patients: a cardiovascular magnetic resonance study of the randomized controlled EXPLORE trial.

PubMed

Elias, Joëlle; van Dongen, Ivo M; Hoebers, Loes P; Ouweneel, Dagmar M; Claessen, Bimmer E P M; Råmunddal, Truls; Laanmets, Peep; Eriksen, Erlend; van der Schaaf, René J; Ioanes, Dan; Nijveldt, Robin; Tijssen, Jan G; Hirsch, Alexander; Henriques, José P S

2017-07-19

The Evaluating Xience and left ventricular function in PCI on occlusiOns afteR STEMI (EXPLORE) trial did not show a significant benefit of percutaneous coronary intervention (PCI) of the concurrent chronic total occlusion (CTO) in ST-segment elevation myocardial infarction (STEMI) patients on global left ventricular (LV) systolic function. However a possible treatment effect will be most pronounced in the CTO territory. Therefore, we aimed to study the effect of CTO PCI compared to no-CTO PCI on the recovery of regional LV function, particularly in the CTO territory. Using cardiovascular magnetic resonance (CMR) we studied 180 of the 302 EXPLORE patients with serial CMR (baseline and 4 months follow-up). Segmental wall thickening (SWT) was quantified on cine images by an independent core laboratory. Dysfunctional segments were defined as SWT < 45%. Dysfunctional segments were further analyzed by viability (transmural extent of infarction (TEI) ≤50%.). All outcomes were stratified for randomization treatment. In the dysfunctional segments in the CTO territory recovery of SWT was better after CTO PCI compared to no-CTO PCI (ΔSWT 17 ± 27% vs 11 ± 23%, p = 0.03). This recovery was most pronounced in the dysfunctional but viable segments(TEI < 50%) (ΔSWT 17 ± 27% vs 11 ± 22%, p = 0.02). Furthermore in the CTO territory, recovery of SWT was significantly better in the dysfunctional segments in patients with Rentrop grade 2-3 collaterals compared to grade 0-1 collaterals to the CTO (16 ± 26% versus 11 ± 24%, p = 0.04). CTO PCI compared with no-CTO PCI is associated with a greater recovery of regional systolic function in the CTO territory, especially in the dysfunctional but viable segments. Further research is needed to evaluate the use of CMR in selecting post-STEMI patients for CTO PCI and the effect of regional LV function recovery on clinical outcome. Trialregister.nl NTR1108 , Date registered NTR: 30-okt-2007.

Automatic regional analysis of myocardial native T1 values: left ventricle segmentation and AHA parcellations.

PubMed

Huang, Hsiao-Hui; Huang, Chun-Yu; Chen, Chiao-Ning; Wang, Yun-Wen; Huang, Teng-Yi

2018-01-01

Native T1 value is emerging as a reliable indicator of abnormal heart conditions related to myocardial fibrosis. Investigators have extensively used the standardized myocardial segmentation of the American Heart Association (AHA) to measure regional T1 values of the left ventricular (LV) walls. In this paper, we present a fully automatic system to analyze modified Look-Locker inversion recovery images and to report regional T1 values of AHA segments. Ten healthy individuals participated in the T1 mapping study with a 3.0 T scanner after providing informed consent. First, we obtained masks of an LV blood-pool region and LV walls by using an image synthesis method and a layer-growing method. Subsequently, the LV walls were divided into AHA segments by identifying the boundaries of the septal regions and by using a radial projection method. The layer-growing method significantly enhanced the accuracy of the derived myocardium mask. We compared the T1 values that were obtained using manual region of interest selections and those obtained using the automatic system. The average T1 difference of the calculated segments was 4.6 ± 1.5%. This study demonstrated a practical and robust method of obtaining native T1 values of AHA segments in LV walls.

Evaluation of left ventricular Tei index (index of myocardial performance) in healthy dogs and dogs with mitral regurgitation.

PubMed

Teshima, Kenji; Asano, Kazushi; Iwanaga, Koji; Koie, Hiroshi; Uechi, Masami; Kato, Yuka; Kutara, Kenji; Kanno, Nobuyuki; Seki, Mamiko; Edamura, Kazuya; Hasegawa, Atsuhiko; Tanaka, Shigeo

2007-02-01

The left ventricular (LV) Tei index (index of myocardial performance) has been demonstrated to be clinically useful in estimating comprehensive LV function, including the systolic and diastolic performances, in various human cardiac diseases. The purposes of this study were to validate the correlation between the LV Tei index and LV function obtained by cardiac catheterization in healthy dogs, and to evaluate the LV Tei index in dogs with naturally occurring mitral regurgitation (MR). In healthy dogs, the LV Tei index was significantly correlated with the LV peak +dP/dt (r = -0.89) and LV peak -dP/dt (r=0.87). The LV Tei index significantly increased in dogs with MR compared with normal dogs and significantly increased with progressively more severe clinical signs due to heart failure. The elevation of the LV Tei index in dogs with symptomatic MR appears to be associated with shortening of ejection time. The LV Tei index significantly increased with age and was not correlated with heart rate and body weight in normal dogs. In conclusion, our study demonstrated that the LV Tei index was measurable in dogs and not influenced by heart rate and body weight. The LV Tei index significantly increased with the progression of clinical signs in MR dogs. In particular, the elevation of the LV Tei index in dogs with symptomatic MR due to shortening of ejection time may suggest LV systolic dysfunction and the decrement of forward stroke volume.

Targeted Injection of a Biocomposite Material Alters Macrophage and Fibroblast Phenotype and Function following Myocardial Infarction: Relation to Left Ventricular Remodeling

PubMed Central

McGarvey, Jeremy R.; Pettaway, Sara; Shuman, James A.; Novack, Craig P.; Zellars, Kia N.; Freels, Parker D.; Echols, Randall L.; Burdick, Jason A.; Gorman, Joseph H.; Gorman, Robert C.

2014-01-01

A treatment target for progressive left ventricular (LV) remodeling prevention following myocardial infarction (MI) is to affect structural changes directly within the MI region. One approach is through targeted injection of biocomposite materials, such as calcium hydroxyapatite microspheres (CHAM), into the MI region. In this study, the effects of CHAM injections upon key cell types responsible for the MI remodeling process, the macrophage and fibroblast, were examined. MI was induced in adult pigs before randomization to CHAM injections (20 targeted 0.1-ml injections within MI region) or saline. At 7 or 21 days post-MI (n = 6/time point per group), cardiac magnetic resonance imaging was performed, followed by macrophage and fibroblast isolation. Isolated macrophage profiles for monocyte chemotactic macrophage inflammatory protein-1 as measured by real-time polymerase chain reaction increased at 7 days post-MI in the CHAM group compared with MI only (16.3 ± 6.6 versus 1.7 ± 0.6 cycle times values, P < 0.05), and were similar by 21 days post-MI. Temporal changes in fibroblast function and smooth muscle actin (SMA) expression relative to referent control (n = 5) occurred with MI. CHAM induced increases in fibroblast proliferation, migration, and SMA expression—indicative of fibroblast transformation. By 21 days, CHAM reduced LV dilation (diastolic volume: 75 ± 2 versus 97 ± 4 ml) and increased function (ejection fraction: 48 ± 2% versus 38 ± 2%) compared with MI only (both P < 0.05). This study identified that effects on macrophage and fibroblast differentiation occurred with injection of biocomposite material within the MI, which translated into reduced adverse LV remodeling. These unique findings demonstrate that biomaterial injections impart biologic effects upon the MI remodeling process over any biophysical effects. PMID:25022514

A Five-Dimensional Mathematical Model for Regional and Global Changes in Cardiac Uptake and Motion

NASA Astrophysics Data System (ADS)

Pretorius, P. H.; King, M. A.; Gifford, H. C.

2004-10-01

The objective of this work was to simultaneously introduce known regional changes in contraction pattern and perfusion to the existing gated Mathematical Cardiac Torso (MCAT) phantom heart model. We derived a simple integral to calculate the fraction of the ellipsoidal volume that makes up the left ventricle (LV), taking into account the stationary apex and the moving base. After calculating the LV myocardium volume of the existing beating heart model, we employed the property of conservation of mass to manipulate the LV ejection fraction to values ranging between 13.5% and 68.9%. Multiple dynamic heart models that differ in degree of LV wall thickening, base-to-apex motion, and ejection fraction, are thus available for use with the existing MCAT methodology. To introduce more complex regional LV contraction and perfusion patterns, we used composites of dynamic heart models to create a central region with little or no motion or perfusion, surrounded by a region in which the motion and perfusion gradually reverts to normal. To illustrate this methodology, the following gated cardiac acquisitions for different clinical situations were simulated analytically: 1) reduced regional motion and perfusion; 2) same perfusion as in (1) without motion intervention; and 3) washout from the normal and diseased myocardial regions. Both motion and perfusion can change dynamically during a single rotation or multiple rotations of a simulated single-photon emission computed tomography acquisition system.

Takotsubo cardiomyopathy in the case of 72-year-old teacher after work-related psychological stress. Evolution of left ventricular longitudinal strain - Delayed but complete recovery in automated function imaging (AFI).

PubMed

Wierzbowska-Drabik, Karina; Marcinkiewicz, Andrzej; Hamala, Piotr; Trzos, Ewa; Lipiec, Piotr; Kurpesa, Małgorzata; Kręcki, Radosław; Plewka, Michał; Kasprzak, Jarosław D

2017-06-19

Takotsubo cardiomyopathy (TC) is related to a transient systolic dysfunction of left ventricle (LV), accompanied by clinical and electrocardiographic symptoms of myocardial ischemia in the absence of hemodynamically significant coronary artery disease. Takotsubo cardiomyopathy is usually provoked by a psychologically or/and physically stressful event which may be related to occupational activities. Although visually assessed evolution of LV function is well documented, the data concerning strain changes is sparse and various patterns of deformation abnormalities are suggested. We have described a 72-year-old woman with chest pain related to a lecture given at the meeting of the Senior University, fulfilling all the Mayo Clinic criteria of the TC. The longitudinal strain analysis with automated function imaging (AFI) documented severe impairment and stepwise recovery of regional and global LV contractility. The case described confirms that accurate diagnosis, treatment and documenting of functional improvement in takotsubo cardiomyopathy may enable the return to occupational activities even for elderly persons. Int J Occup Med Environ Health 2017;30(4):681-683. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Automated classification of LV regional wall motion based on spatio-temporal profiles from cardiac cine magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Mantilla, Juan; Garreau, Mireille; Bellanger, Jean-Jacques; Paredes, José Luis

2013-11-01

Assessment of the cardiac Left Ventricle (LV) wall motion is generally based on visual inspection or quantitative analysis of 2D+t sequences acquired in short-axis cardiac cine-Magnetic Resonance Imaging (MRI). Most often, cardiac dynamic is globally analized from two particular phases of the cardiac cycle. In this paper, we propose an automated method to classify regional wall motion in LV function based on spatio-temporal pro les and Support Vector Machines (SVM). This approach allows to obtain a binary classi cation between normal and abnormal motion, without the need of pre-processing and by exploiting all the images of the cardiac cycle. In each short- axis MRI slice level (basal, median, and apical), the spatio-temporal pro les are extracted from the selection of a subset of diametrical lines crossing opposites LV segments. Initialized at end-diastole phase, the pro les are concatenated with their corresponding projections into the succesive temporal phases of the cardiac cycle. These pro les are associated to di erent types of information that derive from the image (gray levels), Fourier, Wavelet or Curvelet domains. The approach has been tested on a set of 14 abnormal and 6 healthy patients by using a leave-one-out cross validation and two kernel functions for SVM classi er. The best classi cation performance is yielded by using four-level db4 wavelet transform and SVM with a linear kernel. At each slice level the results provided a classi cation rate of 87.14% in apical level, 95.48% in median level and 93.65% in basal level.

Left ventricular lead placement in the latest activated region guided by coronary venous electroanatomic mapping.

PubMed

Rad, Masih Mafi; Blaauw, Yuri; Dinh, Trang; Pison, Laurent; Crijns, Harry J; Prinzen, Frits W; Vernooy, Kevin

2015-01-01

Left ventricular (LV) lead placement in the latest activated region is an important determinant of response to cardiac resynchronization therapy (CRT). We investigated the feasibility of coronary venous electroanatomic mapping (EAM) to guide LV lead placement to the latest activated region. Twenty-five consecutive CRT candidates with left bundle-branch block underwent intra-procedural coronary venous EAM using EnSite NavX. A guidewire was used to map the coronary veins during intrinsic activation, and to test for phrenic nerve stimulation (PNS). The latest activated region, defined as the region with an electrical delay >75% of total QRS duration, was located anterolaterally in 18 (basal, n = 10; mid, n = 8) and inferolaterally in 6 (basal, n = 3; mid, n = 3). In one patient, identification of the latest activated region was impeded by limited coronary venous anatomy. In patients with >1 target vein (n = 12), the anatomically targeted inferolateral vein was rarely the vein with maximal electrical delay (n = 3). A concordant LV lead position was achieved in 18 of 25 patients. In six patients, this was hampered by PNS (n = 4), lead instability (n = 1), and coronary vein stenosis (n = 1). Coronary venous EAM can be used intraprocedurally to guide LV lead placement to the latest activated region free of PNS. This approach especially contributes to optimization of LV lead electrical delay in patients with multiple target veins. Conventional anatomical LV lead placement strategy does not target the vein with maximal electrical delay in many of these patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Arterial wave reflection and subclinical left ventricular systolic dysfunction.

PubMed

Russo, Cesare; Jin, Zhezhen; Takei, Yasuyoshi; Hasegawa, Takuya; Koshaka, Shun; Palmieri, Vittorio; Elkind, Mitchell Sv; Homma, Shunichi; Sacco, Ralph L; Di Tullio, Marco R

2011-03-01

Increased arterial wave reflection is a predictor of cardiovascular events and has been hypothesized to be a cofactor in the pathophysiology of heart failure. Whether increased wave reflection is inversely associated with left-ventricular (LV) systolic function in individuals without heart failure is not clear. Arterial wave reflection and LV systolic function were assessed in 301 participants from the Cardiovascular Abnormalities and Brain Lesions (CABL) study using two-dimensional echocardiography and applanation tonometry of the radial artery to derive central arterial waveform by a validated transfer function. Aortic augmentation index (AIx) and wasted energy index (WEi) were used as indices of wave reflection. LV systolic function was measured by LV ejection fraction (LVEF) and tissue Doppler imaging (TDI). Mitral annulus peak systolic velocity (Sm), peak longitudinal strain and strain rate were measured. Participants with history of coronary artery disease, atrial fibrillation, LVEF less than 50% or wall motion abnormalities were excluded. Mean age of the study population was 68.3 ± 10.2 years (64.1% women, 65% hypertensive). LV systolic function by TDI was lower with increasing wave reflection, whereas LVEF was not. In multivariate analysis, TDI parameters of LV longitudinal systolic function were significantly and inversely correlated to AIx and WEi (P values from 0.05 to 0.002). In a community cohort without heart failure and with normal LVEF, an increased arterial wave reflection was associated with subclinical reduction in LV systolic function assessed by novel TDI techniques. Further studies are needed to investigate the prognostic implications of this relationship.

The known two types of transglutaminases regulate immune and stress responses in white shrimp, Litopenaeus vannamei.

PubMed

Chang, Chin-Chyuan; Chang, Hao-Che; Liu, Kuan-Fu; Cheng, Winton

2016-06-01

Transglutaminases (TGs) play critical roles in blood coagulation, immune responses, and other biochemical functions, which undergo post-translational remodeling such as acetylation, phosphorylation and fatty acylation. Two types of TG have been identified in white shrimp, Litopenaeus vannamei, and further investigation on their potential function was conducted by gene silencing in the present study. Total haemocyte count (THC), differential haemocyte count (DHC), phenoloxidase activity, respiratory bursts (release of superoxide anion), superoxide dismutase activity, transglutaminase (TG) activity, haemolymph clotting time, and phagocytic activity and clearance efficiency to the pathogen Vibrio alginolyticus were measured when shrimps were individually injected with diethyl pyrocarbonate-water (DEPC-H2O) or TG dsRNAs. In addition, haemolymph glucose and lactate, and haemocytes crustin, lysozyme, crustacean hyperglycemic hormone (CHH), transglutaminaseI (TGI), transglutaminaseII (TGII) and clotting protein (CP) mRNA expression were determined in the dsRNA injected shrimp under hypothermal stress. Results showed that TG activity, phagocytic activity and clearance efficiency were significantly decreased, but THC, hyaline cells (HCs) and haemolymph clotting time were significantly increased in the shrimp which received LvTGI dsRNA and LvTGI + LvTGII dsRNA after 3 days. However, respiratory burst per haemocyte was significantly decreased in only LvTGI + LvTGII silenced shrimp. In hypothermal stress studies, elevation of haemolymph glucose and lactate was observed in all treated groups, and were advanced in LvTGI and LvTGI + LvTGII silenced shrimp following exposure to 22 °C. LvCHH mRNA expression was significantly up-regulated, but crustin and lysozyme mRNA expressions were significantly down-regulated in LvTGI and LvTGI + LvTGII silenced shrimp; moreover, LvTGII was significantly increased, but LvTGI was significantly decreased in LvTGI silenced shrimp following exposure to 28 and 22 °C. Knockdown of LvTGI and LvTGI + LvTGII also significantly increased the mortality of L. vannamei challenged with the pathogen V. alginolyticus. The same consequences have been confirmed in LvTGII silenced shrimp in our previous study. These results indicate that LvTGI and LvTGII not only reveal a complementary effect in gene expression levels but also play a key function in the immune defence mechanism of shrimp, by regulating the haemolymph coagulation, immune parameters and immune related gene expression, and in the regulation of carbohydrate metabolism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Long-Term Outcome of Administration of c-kitPOS Cardiac Progenitor Cells After Acute Myocardial Infarction: Transplanted Cells Do Not Become Cardiomyocytes, Structural and Functional Improvement and Proliferation of Endogenous Cells Persist for at Least One Year

PubMed Central

Tang, Xian-Liang; Li, Qianhong; Rokosh, Gregg; Sanganalmath, Santosh K.; Chen, Ning; Ou, Qinghui; Stowers, Heather; Hunt, Greg; Bolli, Roberto

2016-01-01

RATIONALE Cardiac progenitor cells (CPCs) improve left ventricular (LV) remodeling and function after acute or chronic myocardial infarction (MI). However, the long-term (>5 weeks) effects, potential tumorigenicity, and fate of transplanted CPCs are unknown. OBJECTIVE To assess the outcome of CPC therapy at 1 year. METHODS AND RESULTS Female rats underwent a 90-min coronary occlusion; 4 h after reperfusion, they received intracoronarily vehicle or 1 million male, syngeneic CPCs. One year later, CPC-treated rats exhibited smaller scars and more viable myocardium in the risk region, along with improved LV remodeling and regional and global LV function. No tumors were observed. Some transplanted (Y-chromosomePOS) CPCs (or their progeny) persisted and continued to proliferate, but they failed to acquire a mature cardiomyocyte phenotype and were too few (4-8% of nuclei) to account for the benefits of CPC therapy. Surprisingly, CPC transplantation triggered a prolonged proliferative response of endogenous cells, resulting in increased formation of endothelial cells and Y-chromosomeNEG CPCs for 12 months and increased formation, for at least 7 months, of small cells that expressed cardiomyocytic proteins (α-sarcomeric actin) but did not have a mature cardiomyocyte phenotype. CONCLUSIONS The beneficial effects of CPCs on LV remodeling and dysfunction are sustained for at least 1 year, and thus are likely to be permanent. Since transplanted CPCs do not differentiate into mature myocytes, their major mechanism of action must involve paracrine actions. These paracrine mechanisms could be very prolonged because some CPCs engraft, proliferate, and persist at 1 year. This is the first report that transplantation of any cell type in the heart induces a proliferative response that lasts at least 1 year. The results strongly support the safety and clinical utility of CPC therapy. PMID:26838790

Ventricular structure, function, and mechanics at high altitude: chronic remodeling in Sherpa vs. short-term lowlander adaptation.

PubMed

Stembridge, Mike; Ainslie, Philip N; Hughes, Michael G; Stöhr, Eric J; Cotter, James D; Nio, Amanda Q X; Shave, Rob

2014-08-01

Short-term, high-altitude (HA) exposure raises pulmonary artery systolic pressure (PASP) and decreases left-ventricular (LV) volumes. However, relatively little is known of the long-term cardiac consequences of prolonged exposure in Sherpa, a highly adapted HA population. To investigate short-term adaptation and potential long-term cardiac remodeling, we studied ventricular structure and function in Sherpa at 5,050 m (n = 11; 31 ± 13 yr; mass 68 ± 10 kg; height 169 ± 6 cm) and lowlanders at sea level (SL) and following 10 ± 3 days at 5,050 m (n = 9; 34 ± 7 yr; mass 82 ± 10 kg; height 177 ± 6 cm) using conventional and speckle-tracking echocardiography. At HA, PASP was higher in Sherpa and lowlanders compared with lowlanders at SL (both P < 0.05). Sherpa had smaller right-ventricular (RV) and LV stroke volumes than lowlanders at SL with lower RV systolic strain (P < 0.05) but similar LV systolic mechanics. In contrast to LV systolic mechanics, LV diastolic, untwisting velocity was significantly lower in Sherpa compared with lowlanders at both SL and HA. After partial acclimatization, lowlanders demonstrated no change in the RV end-diastolic area; however, both RV strain and LV end-diastolic volume were reduced. In conclusion, short-term hypoxia induced a reduction in RV systolic function that was also evident in Sherpa following chronic exposure. We propose that this was consequent to a persistently higher PASP. In contrast to the RV, remodeling of LV volumes and normalization of systolic mechanics indicate structural and functional adaptation to HA. However, altered LV diastolic relaxation after chronic hypoxic exposure may reflect differential remodeling of systolic and diastolic LV function. Copyright © 2014 the American Physiological Society.

Ventricular structure, function, and mechanics at high altitude: chronic remodeling in Sherpa vs. short-term lowlander adaptation

PubMed Central

Ainslie, Philip N.; Hughes, Michael G.; Stöhr, Eric J.; Cotter, James D.; Nio, Amanda Q. X.; Shave, Rob

2014-01-01

Short-term, high-altitude (HA) exposure raises pulmonary artery systolic pressure (PASP) and decreases left-ventricular (LV) volumes. However, relatively little is known of the long-term cardiac consequences of prolonged exposure in Sherpa, a highly adapted HA population. To investigate short-term adaptation and potential long-term cardiac remodeling, we studied ventricular structure and function in Sherpa at 5,050 m (n = 11; 31 ± 13 yr; mass 68 ± 10 kg; height 169 ± 6 cm) and lowlanders at sea level (SL) and following 10 ± 3 days at 5,050 m (n = 9; 34 ± 7 yr; mass 82 ± 10 kg; height 177 ± 6 cm) using conventional and speckle-tracking echocardiography. At HA, PASP was higher in Sherpa and lowlanders compared with lowlanders at SL (both P < 0.05). Sherpa had smaller right-ventricular (RV) and LV stroke volumes than lowlanders at SL with lower RV systolic strain (P < 0.05) but similar LV systolic mechanics. In contrast to LV systolic mechanics, LV diastolic, untwisting velocity was significantly lower in Sherpa compared with lowlanders at both SL and HA. After partial acclimatization, lowlanders demonstrated no change in the RV end-diastolic area; however, both RV strain and LV end-diastolic volume were reduced. In conclusion, short-term hypoxia induced a reduction in RV systolic function that was also evident in Sherpa following chronic exposure. We propose that this was consequent to a persistently higher PASP. In contrast to the RV, remodeling of LV volumes and normalization of systolic mechanics indicate structural and functional adaptation to HA. However, altered LV diastolic relaxation after chronic hypoxic exposure may reflect differential remodeling of systolic and diastolic LV function. PMID:24876358

Dietary pattern, the metabolic syndrome, and left ventricular mass and systolic function: the Multi-Ethnic Study of Atherosclerosis.

PubMed

Liu, Longjian; Nettleton, Jennifer A; Bertoni, Alain G; Bluemke, David A; Lima, João A; Szklo, Moyses

2009-08-01

Little is known about the relations between dietary patterns, metabolic dysfunction, and left ventricular (LV) function. The objective was to examine associations of dietary patterns with LV mass and function and to explore the potential role of metabolic dysfunction in the association between diet and LV function. Dietary patterns that maximally explained the variation in metabolic syndrome (MetSyn) components were derived by using reduced rank regression (RRR). LV mass, stroke volume, and LV ejection fraction (LVEF) were measured by magnetic resonance imaging. Associations between dietary pattern and LV indexes were analyzed cross-sectionally. A total of 4601 participants aged 45-84 y and free of clinical cardiovascular disease were studied. The primary RRR dietary pattern score was positively correlated with intake of foods with a high glycemic index, high-fat meats, cheeses, and processed foods and negatively correlated with low intakes of vegetables, soy, fruit, green and black tea, low-fat dairy desserts, seeds and nuts, and fish. Multivariate analyses showed that each 1-unit increase in the RRR dietary pattern score was associated with a 0.32-g/m(2) increase in LV mass/body surface area, a 0.43-mL/m(2) decrease in stroke volume/body surface area, and a 0.21% decrease in LVEF. The associations of the RRR dietary pattern score with LV mass and stroke indexes were attenuated and became nonsignificant after adjustment for all MetSyn components (P > 0.05). The results suggest that the RRR dietary pattern is significantly associated with unfavorable LV function, and this association might be mediated by metabolic dysfunction. Given the cross-sectional nature of our study, these results must be confirmed with the use of longitudinal data.

Impaired left ventricular diastolic function is related to the formation of left ventricular apical thrombus in patients with acute anterior myocardial infarction.

PubMed

Choi, Ung Lim; Park, Jae-Hyeong; Sun, Byung Joo; Oh, Jin Kyung; Seong, Seok Woo; Lee, Jae-Hwan; Choi, Si Wan; Jeong, Jin-Ok; Kwon, In Sun; Seong, In-Whan

2018-05-01

Left ventricular (LV) apical thrombus is a clinically important complication which can cause systemic embolization in patients with anterior acute myocardial infarction (AMI). Systolic dysfunction has been a risk factor for developing LV apical thrombus in AMI patients. However, the role of diastolic dysfunction in the development of LV apical thrombus in these patients is still unknown. We performed this study to evaluate whether diastolic dysfunction can influence the development of LV apical thrombus in anterior AMI patients. We retrospectively analyzed all consecutive anterior AMI patients with available echocardiographic images within 1 month from January 2005 to April 2016. After gathering clinical characteristics from their medical records, systolic and diastolic functions were analyzed from digitally stored echocardiographic images. We included a total of 1045 patients (748 males, mean age 64 ± 12 years) with anterior AMI, and 494 (47%) were diagnosed as STEMI. The incidence of LV apical thrombus was 3.3% (34/1045). The LV apical thrombus group had larger LV diastolic dimension, larger LV diastolic and systolic volumes, and lower LVEF than the no LV thrombus group. The LV apical thrombus group showed higher mitral E velocity over mitral annular E' velocity ratio, an indicator of LV end-diastolic pressure (P < 0.001). In the LV apical thrombus group, the incidence of grade 2 diastolic dysfunction (32 vs 12%, P = 0.001) and grade 3 diastolic dysfunction (26 vs 2%, P < 0.001) were significantly higher than in the no LV apical thrombus group. The presence of more than grade 2 diastolic dysfunction, LVEF and presence of LV apical aneurysm were statistically significant factors associated with LV apical thrombus after the multivariate analysis. In conclusion, along with LV systolic dysfunction and LV apical aneurysm, LV diastolic dysfunction was also related with the presence of LV apical thrombus in patients with anterior AMI.

Characterization of two types of vascular endothelial growth factor from Litopenaeus vannamei and their involvements during WSSV infection.

PubMed

Wang, Zhiwei; Li, Shihao; Li, Fuhua; Yang, Hui; Yang, Fusheng; Xiang, Jianhai

2015-12-01

Vascular endothelial growth factors (VEGFs) are important signaling proteins in VEGF signaling pathway which play key roles in inducing endothelial cell proliferation, migration, angiogenesis, vascular permeability, inhibition of apoptosis and virus infection. In the present study, we isolated and characterized two VEGF genes, LvVEGF1 and LvVEGF2 from Litopenaeus vannamei. The deduced amino acid sequences of both LvVEGF1 and LvVEGF2 contained a signal peptide, a typical PDGF/VEGF domain and a cysteine knot motif (CXCXC). Tissue distribution analysis showed that LvVEGF1 was predominantly expressed in lymphoid organ (Oka) while LvVEGF2 was mainly detected in gill and hemocytes. The transcriptional levels of LvVEGF1 in Oka and LvVEGF2 in gill or hemocytes were apparently up-regulated during WSSV infection. Double-stranded RNA interference was used for further functional studies. The data showed that silencing of LvVEGF1 and LvVEGF2 caused a decrease of the copy numbers of the virus in WSSV infected shrimp and a reduction of the cumulative mortality rate of shrimp during WSSV infection. The present study indicated that LvVEGF1 and LvVEGF2 might facilitate WSSV infection, which provided new evidence to understand the function of VEGF signaling pathway during WSSV infection in shrimp. Copyright © 2015 Elsevier Ltd. All rights reserved.

Left Ventricular Function in Patients with Pulmonary Arterial Hypertension: The Role of Two-Dimensional Speckle Tracking Strain.

PubMed

de Amorim Corrêa, Ricardo; de Oliveira, Fernanda Brito; Barbosa, Marcia M; Barbosa, Jose Augusto A; Carvalho, Taís Soares; Barreto, Michele Campos; Campos, Frederico Thadeu A F; Nunes, Maria Carmo Pereira

2016-09-01

Pulmonary arterial hypertension (PAH) is characterized by elevated mean pulmonary arterial pressure with abnormal right ventricular (RV) pressure overload that may alter left ventricular (LV) function. The aim of this study was to assess the impact of RV pressure overload on LV function in PAH patients using two-dimensional (2D) speckle tracking strain. The study enrolled 37 group 1 PAH patients and 38 age- and gender-matched healthy controls. LV longitudinal and radial 2D strains were measured with and without including the ventricular septum. Six-minute walk test (6MWT) and brain natriuretic peptide (BNP) levels were also obtained in patients with PAH. The mean age of patients was 46.4 ± 14.8 years, 76% women, and 16 patients (43%) had schistosomiasis. Sixteen patients (43%) were in WHO class III or IV under specific treatment for PAH. The overall 6MWT distance was 441 meters, and the BNP levels were 80 pg/mL. Patients with PAH more commonly presented with LV diastolic dysfunction and impairment of RV function when compared to controls. LV global longitudinal and radial strains were lower in patients than in controls (-17.9 ± 2.8 vs. -20.5 ± 1.9; P < 0.001 and 30.8 ± 10.5 vs. 49.8 ± 15.4; P < 0.001, respectively). After excluding septal values, LV longitudinal and radial strains remained lower in patients than in controls. The independent factors associated with global LV longitudinal strain were LV ejection fraction, RV fractional area change, and tricuspid annular systolic motion. This study showed impaired LV contractility in patients with PAH assessed by speckle tracking strain, irrespective of ventricular septal involvement. Global LV longitudinal strain was associated independently with RV fractional area change and tricuspid annular systolic motion, after adjustment for LV ejection fraction. © 2016, Wiley Periodicals, Inc.

Left Ventricular Mass Progression Despite Stable Blood Pressure and Kidney Function in Stage 3 CKD

PubMed Central

Seifert, Michael E.; Fuentes, Lisa de las; Ginsberg, Charles; Rothstein, Marcos; Dietzen, Dennis J.; Cheng, Steven C.; Ross, Will; Windus, David; Dávila-Román, Victor G.; Hruska, Keith A.

2014-01-01

Background/Aims Progressive chronic kidney disease (CKD) is associated with worsening cardiovascular risk not explained by traditional risk factors. Left ventricular hypertrophy (LVH) is an important cardiovascular risk factor, but its progression has not been documented in early CKD. We explored whether progression of LVH in early CKD would occur despite stable kidney function. Methods We conducted a post hoc analysis of a 12-m nth study of lanthanum carbonate in stage 3 CKD, which included longitudinal assessments of cardiovascular biomarkers. Primary outcome for the analysis was the change in LV mass indexed to height in meters2.7 (LVM/Ht2.7). Secondary outcomes were changes in blood pressure (BP), pulse-wave velocity, LV systolic/diastolic function, fibroblast growth factor-23 (FGF23), klotho, and eGFR. Results 31 of 38 original subjects had sufficient data for analysis. LVM/Ht2.7 increased (47 ± 13 vs. 53 ± 13 g/m2.7, P=0.006) over 12 months despite stable BP, stable eGFR and normal LV systolic function. Vascular stiffness and LV diastolic dysfunction persisted throughout the study. Klotho levels decreased (748 ± 289 to 536 ± 410 pg/ml, P=0.03) but were unrelated to changes in LVM/Ht2.7. The change in FGF23/klotho ratio was strongly correlated with changes in LVM/Ht2.7 (r2 0.582, P=0.03). Conclusion Subjects with stage 3 CKD exhibited increasing LV mass, persistent LV diastolic dysfunction and vascular stiffness despite stable kidney function, BP and LV systolic function. Abnormal FGF23 signaling due to reduced klotho expression may be associated with increasing LV mass. These findings deserve further evaluation in a larger population, given the adverse prognostic value of these cardiovascular biomarkers. PMID:24818573

The effect of L-thyroxine treatment on left ventricular functions in children with subclinical hypothyroidism.

PubMed

Çatli, Gönül; Kir, Mustafa; Anik, Ahmet; Yilmaz, Nuh; Böber, Ece; Abaci, Ayhan

2015-02-01

The aim of this study was to search for evidence suggesting treatment for childhood subclinical hypothyroidism (SH) by evaluating left ventricular (LV) functions of children with SH by using M-mode and tissue Doppler echocardiography (TDE). Children with SH and euthyroid healthy children (control group) were enrolled in the study. At baseline and 6 months after euthyroidism was achieved, M-mode and TDE were performed and LV functions were evaluated. Pretreatment parameters of the SH group were compared with those of controls and post-treatment parameters. 31 children with SH and 32 euthyroid healthy children were enrolled in the study. The groups had similar age, gender, puberty and body mass index. Interventricular septum thickness and LV mass index, which are the parameters for LV morphology, were slightly increased in the SH group than in the controls (p<0.05). In TDE, children with SH had significant changes in LV diastolic (lower E'm, higher E/E'm ratio and longer isovolumic relaxation time) and systolic functions (lower isovolumic contraction time) compared with controls (p<0.05). Six months after euthyroidism was achieved, TDE showed a significant improvement of some of the diastolic and systolic parameters (p<0.05). The results of this study showed that SH is associated with subclinical alterations in LV function, and LT4 replacement may improve LV systolic and diastolic parameters. However, since SH is usually a self-limiting process, these improvements in LV functions may simply be associated with the natural course of the disease and/or physiological linear growth of the children. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Doppler echocardiographic assessment of left ventricular diastolic function in 74 boxer dogs with aortic stenosis.

PubMed

Schober, Karsten E; Fuentes, Virginia Luis

2002-05-01

To evaluate left ventricular (LV) diastolic function in boxer dogs with aortic stenosis (AS). LV relaxation, elastic recoil, filling and stiffness have been found to be abnormal in people with AS and were related to disease severity, clinical signs and prognosis. 2-D, M-mode and Doppler echocardiography was done in 74 boxers with AS (55 with mild AS, 7 with moderate AS and 12 with severe AS) and compared with reference values from 66 normal boxers. Measurements included isovolumic relaxation time (IVRT), peak early (E) and late (A) transmitral filling velocities, mitral E wave deceleration time, peak systolic, and early and late (AR) diastolic pulmonary wenous flow velocities and related variables. In addition, left atrial (LA) function, LV dimensions and hypertrophy and LV systolic performance were assessed. Eight dogs (15%) with mild AS had abnormal LV diastolic function, compared with 16 dogs (84%) with moderate or severe AS. Two dogs (3%) had also systolic abnormalities. The flow pattern of delayed relaxation, pseudonormal mitral inflow and restrictive flow were found in 10, 11 and 3 dogs, respectively. IVRT and E:A were heterogeneous in dogs with moderate or severe AS, being either high, normal, or low. Peak AR velocity was significantly higher (p

Economic Evaluation of Low-Vision Rehabilitation for Veterans With Macular Diseases in the US Department of Veterans Affairs.

PubMed

Stroupe, Kevin T; Stelmack, Joan A; Tang, X Charlene; Wei, Yongliang; Sayers, Scott; Reda, Domenic J; Kwon, Ellen; Massof, Robert W

2018-05-01

Examining costs and consequences of different low-vision (LV) programs provides important information about resources needed to expand treatment options efficiently. To examine the costs and consequences of LV rehabilitation or basic LV services. The US Department of Veterans Affairs (VA) Low Vision Intervention Trial (LOVIT) II was conducted from September 27, 2010, to July 31, 2014, at 9 VA facilities and included 323 veterans with macular diseases and a best-corrected distance visual acuity of 20/50 to 20/200. Veterans were randomized to receive basic LV services that provided LV devices without therapy, or LV rehabilitation that added a therapist to LV services who provided instruction and homework on using LV devices, eccentric viewing, and environmental modification. We compared costs and consequences between these groups. Low-vision devices without therapy and LV devices with therapy. Costs of providing basic LV services or LV rehabilitation were assessed. We measured consequences as changes in functional visual ability from baseline to follow-up 4 months after randomization using the VA Low Vision Visual Functioning Questionnaire. Visual ability was measured in dimensionless log odds units (logits). Of 323 randomized patients, the mean (SD) age was 80 (10.5) years, 314 (97.2%) were men, and 292 (90.4%) were white. One hundred sixty (49.5%) received basic LV services and 163 (50.1%) received LV rehabilitation. The mean (SD) total direct health care costs per patient were similar between patients who were randomized to receive basic LV services ($1662 [$671]) or LV rehabilitation ($1788 [$864]) (basic LV services, $126 lower; 95% CI, $299 lower to $35 higher; P = .15). However, basic LV services required less time and had lower transportation costs. Patients receiving LV rehabilitation had greater improvements in overall visual ability, reading ability, visual information processing, and visual motor skill scores.

Left ventricular mechanics in humans with high aerobic fitness: adaptation independent of structural remodelling, arterial haemodynamics and heart rate

PubMed Central

Stöhr, Eric J; McDonnell, Barry; Thompson, Jane; Stone, Keeron; Bull, Tom; Houston, Rory; Cockcroft, John; Shave, Rob

2012-01-01

Individuals with high aerobic fitness have lower systolic left ventricular strain, rotation and twist (‘left ventricular (LV) mechanics’) at rest, suggesting a beneficial reduction in LV myofibre stress and more efficient systolic function. However, the mechanisms responsible for this functional adaptation are not known and the influence of aerobic fitness on LV mechanics during dynamic exercise has never been studied. We assessed LV mechanics, LV wall thickness and dimensions, central augmentation index (AIx), aortic pulse wave velocity (aPWV), blood pressure and heart rate in 28 males (age: 21 ± 2 years SD) with a consistent physical activity level (no change >6 months). Individuals were examined at rest and during exercise (40% peak exercise capacity) and separated post hoc into a moderate and high aerobic fitness group (: 49 ± 5 and 63 ± 7 ml kg−1 min−1, respectively, P < 0.0001). At rest and during exercise, there were no significant differences in gross LV structure, AIx, blood pressure or heart rate (P > 0.05). However, for the same AIx, the high group had significantly lower LV apical rotation (P = 0.002) and LV twist (P = 0.003) while basal rotation and strain indices did not differ between groups (P > 0.05). We conclude that young males with high aerobic fitness have lower LV apical rotation at rest and during submaximal exercise that can occur without changes in gross LV structure, arterial haemodynamics or heart rate. The findings suggest a previously unknown type of physiological adaptation of the left ventricle that may have important implications for exercise training in older individuals and patient populations in which exercise training has previously failed to show clear benefits for LV function. PMID:22431336

Three-dimensional changes in left and right ventricular geometry in chronic mitral regurgitation.

PubMed

Young, A A; Orr, R; Smaill, B H; Dell'Italia, L J

1996-12-01

Regional three-dimensional (3-D) right (RV) and left ventricular (LV) geometry was studied in eight dogs before and 5-6 mo after induction of mitral regurgitation (MR). Ventricular shape changes were quantified with a 3-D finite-element model fitted to chamber contours traced on cardiac magnetic resonance images. MR increased LV end-diastolic volume (LVEDV; 99 vs. 57 ml; P < 0.001) and LV stroke volume (LVSV; 55 vs. 26 ml; P < 0.001). In contrast, RVEDV decreased (45 vs. 55 ml; P < 0.01), whereas SV was maintained. LV mass (free wall plus septum) increased (115 vs. 94 g; P < 0.05), whereas RV free-wall mass was relatively unchanged. Shape changes due to MR were characterized by a marked (7.4-mm) rightward shift of the septum relative to the lateral LV free wall at end diastole. In contrast, the distance from the RV free wall to the lateral LV free wall was relatively unchanged (2.7 mm). The distance between the LV lateral free wall and septum increased more than the distance between the anterior and posterior LV walls (22 vs. 15%; P = 0.04). During systole, the displacement of the septum into the LV increased significantly (7.3 vs. 2.9 mm; P < 0.01). Consistent with the end-diastolic dimension changes, LV endocardial circumferential curvature was decreased at end diastole to a greater extent in the anterior and posterior walls than in the septal and lateral walls (P < 0.01). Thus chronic MR produced an asymmetric LV dilatation with regional variation in geometry. The septum increased its contribution to the LVSV at the expense of RVEDV. RVSV was maintained, possibly by ventricular interaction.

Impact of a systolic parameter, defined as the ratio of right brachial pre-ejection period to ejection time, on the relationship between brachial-ankle pulse wave velocity and left ventricular diastolic function.

PubMed

Hsu, Po-Chao; Lin, Tsung-Hsien; Lee, Chee-Siong; Chu, Chun-Yuan; Su, Ho-Ming; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung

2011-04-01

Arterial stiffness is correlated with left ventricular (LV) diastolic function as well as susceptibility to LV systolic function. Therefore, if LV systolic function is not known, the relationship between arterial stiffness and LV diastolic function is difficult to determine. A total of 260 patients were included in the study. The brachial-ankle pulse wave velocity (baPWV) and the ratio of right brachial pre-ejection period to ejection time (rbPEP/rbET) were measured using an ABI-form device. Patients were classified into four groups. Groups 1, 2, 3 and 4 were patients with rbPEP/rbET and baPWV below the median, rbPEP/rbET above but baPWV below the median, rbPET/rbET below but baPWV above the median, and rbPET/rbET and baPWV above the median, respectively. The LV ejection fractions in groups 1 and 3 were higher than those in groups 2 and 4 (P<0.001 for all). Patients in group 1 had a lower left atrial volume index (LAVI) and higher early diastolic mitral annular velocity (Ea) than patients in the other groups (P≤0.002). Patients in group 2 had a LAVI and ratio of transmitral E wave velocity to Ea that were comparable to those in groups 3 and 4. In conclusion, rbPEP/rbET had an impact on the relationship between baPWV and LV diastolic function. In patients with high rbPEP/rbET but low baPWV, low baPWV may not indicate good LV diastolic function but implies that cardiac dysfunction may precede vascular dysfunction in such patients. When interpreting the relationship between baPWV and LV diastolic function, the rbPEP/rbET value obtained from the same examination should be considered.

Altered myofilament structure and function in dogs with Duchenne muscular dystrophy cardiomyopathy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ait Mou, Younss; Lacampagne, Alain; Irving, Thomas

Aim Duchenne Muscular Dystrophy (DMD) is associated with progressive depressed left ventricular (LV) function. However, DMD effects on myofilament structure and function are poorly understood. Golden Retriever Muscular Dystrophy (GRMD) is a dog model of DMD recapitulating the human form of DMD. Objective The objective of this study is to evaluate myofilament structure and function alterations in GRMD model with spontaneous cardiac failure. Methods and results We have employed synchrotron X-rays diffraction to evaluate myofilament lattice spacing at various sarcomere lengths (SL) on permeabilized LV myocardium. We found a negative correlation between SL and lattice spacing in both sub-epicardium (EPI)more » and sub-endocardium (ENDO) LV layers in control dog hearts. In the ENDO of GRMD hearts this correlation is steeper due to higher lattice spacing at short SL (1.9 μm). Furthermore, cross-bridge cycling indexed by the kinetics of tension redevelopment (ktr) was faster in ENDO GRMD myofilaments at short SL. We measured post-translational modifications of key regulatory contractile proteins. S-glutathionylation of cardiac Myosin Binding Protein-C (cMyBP-C) was unchanged and PKA dependent phosphorylation of the cMyBP-C was significantly reduced in GRMD ENDO tissue and more modestly in EPI tissue. Conclusions We found a gradient of contractility in control dogs' myocardium that spreads across the LV wall, negatively correlated with myofilament lattice spacing. Chronic stress induced by dystrophin deficiency leads to heart failure that is tightly associated with regional structural changes indexed by increased myofilament lattice spacing, reduced phosphorylation of regulatory proteins and altered myofilament contractile properties in GRMD dogs.« less

Aortic elasticity and left ventricular function after arterial switch operation: MR imaging--initial experience.

PubMed

Grotenhuis, Heynric B; Ottenkamp, Jaap; Fontein, Duveken; Vliegen, Hubert W; Westenberg, Jos J M; Kroft, Lucia J M; de Roos, Albert

2008-12-01

To prospectively assess aortic dimensions, aortic elasticity, aortic valve competence, and left ventricular (LV) systolic function in patients after the arterial switch operation (ASO) by using magnetic resonance (MR) imaging. Informed consent was obtained from all participants for this local ethics committee-approved study. Fifteen patients (11 male patients, four female patients; mean age, 16 years +/- 4 [standard deviation]; imaging performed 16.1 years after surgery +/- 3.7) and 15 age- and sex-matched control subjects (11 male subjects, four female subjects; mean age, 16 years +/- 4) were evaluated. Velocity-encoded MR imaging was used to assess aortic pulse wave velocity (PWV), and a balanced turbo-field-echo sequence was used to assess aortic root distensibility. Standard velocity-encoded and multisection-multiphase imaging sequences were used to assess aortic valve function, systolic LV function, and LV mass. The two-tailed Mann-Whitney U test and Spearman rank correlation coefficient were used for statistical analysis. Patients treated with the ASO showed aortic root dilatation at three predefined levels (mean difference, 5.7-9.4 mm; P < or = .007) and reduced aortic elasticity (PWV of aortic arch, 5.1 m/sec +/- 1.2 vs 3.9 m/sec +/- 0.7, P = .004; aortic root distensibility, [2.2 x 10(-3)] x mm Hg(-1) +/- 1.8 vs [4.9 x 10(-3)] x mm Hg(-1) +/- 2.9, P < .01) compared with control subjects. Minor degrees of aortic regurgitation (AR) were present (AR fraction, 5% +/- 3 in patients vs 1% +/- 1 in control subjects; P < .001). Patients had impaired systolic LV function (LV ejection fraction [LVEF], 51% +/- 6 vs 58% +/- 5 in control subjects; P = .003), in addition to enlarged LV dimensions (end-diastolic volume [EDV], 112 mL/m(2) +/- 13 vs 95 mL/m(2) +/- 16, P = .007; end-systolic volume [ESV], 54 mL/m(2) +/- 11 vs 39 mL/m(2) +/- 7, P < .001). Degree of AR predicted decreased LVEF (r = 0.41, P = .026) and was correlated with increased LV dimensions (LV EDV: r = 0.48, P = .008; LV ESV: r = 0.67, P < .001). Aortic root dilatation and reduced elasticity of the proximal aorta are frequently observed in patients who have undergone the ASO, in addition to minor degrees of AR, reduced LV systolic function, and increased LV dimensions. RSNA, 2008

Gender differences in left ventricular function in patients with isolated aortic stenosis.

PubMed

Favero, Luca; Giordan, Massimo; Tarantini, Giuseppe; Ramondo, Angelo Bruno; Cardaioli, Paolo; Isabella, Giambattista; Chioin, Raffaello; Lupia, Mario; Razzolini, Renato

2003-05-01

Hypertrophic response of the left ventricle to systolic overload in aortic stenosis appears to be gender-dependent. To examine gender-related differences in left ventricular (LV) function in patients with isolated severe aortic stenosis, 145 patients (65 women, 80 men; mean age 66 +/- 8 years; range: 50 to 89 years) with aortic valve area <0.8 cm2 who underwent cardiac catheterization were studied. No patient had associated myocardial, coronary or other valve disease; patients with diabetes mellitus and systemic hypertension were excluded. No significant differences were seen in aortic valve area between men and women. Neither were there any significant gender-related differences in LV end-systolic and end-diastolic volumes, LV end-diastolic pressure, LV mass indexed by body surface area, LV mass:volume ratio, LV mass:height ratio, elastic stiffness constant, ejection fraction, pulmonary wedge pressure, pulmonary arteriolar resistance and preload. Women showed significantly higher mean transaortic gradient, LV peak systolic pressure and peak systolic stress, end-systolic stress:end-systolic volume ratio, heart rate and cardiac index. In the subgroup of patients with LV pressure >199 mmHg, the mass:volume ratio was increased in men compared with women; of note, the mass:volume ratio in women was not increased in this subgroup compared with the general population. LV pump function in this subgroup was normal and did not differ between men and women. Although no clear-cut difference in hemodynamic parameters was seen, there was a trend towards a less compensatory increase in LV mass in females.

Ventricular untwisting: a temporal link between left ventricular relaxation and suction.

PubMed

Notomi, Yuichi; Popovic, Zoran B; Yamada, Hirotsugu; Wallick, Don W; Martin, Maureen G; Oryszak, Stephanie J; Shiota, Takahiro; Greenberg, Neil L; Thomas, James D

2008-01-01

Left ventricular (LV) untwisting starts early during the isovolumic relaxation phase and proceeds throughout the early filling phase, releasing elastic energy stored by the preceding systolic deformation. Data relating untwisting, relaxation, and intraventricular pressure gradients (IVPG), which represent another manifestation of elastic recoil, are sparse. To understand the interaction between LV mechanics and inflow during early diastole, Doppler tissue images (DTI), catheter-derived pressures (apical and basal LV, left atrial, and aortic), and LV volume data were obtained at baseline, during varying pacing modes, and during dobutamine and esmolol infusion in seven closed-chest anesthetized dogs. LV torsion and torsional rate profiles were analyzed from DTI data sets (apical and basal short-axis images) with high temporal resolution (6.5 +/- 0.7 ms). Repeated-measures regression models showed moderately strong correlation of peak LV twisting with peak LV untwisting rate (r = 0.74), as well as correlations of peak LV untwisting rate with the time constant of LV pressure decay (tau, r = -0.66) and IVPG (r = 0.76, P < 0.0001 for all). In a multivariate analysis, peak LV untwisting rate was an independent predictor of tau and IVPG (P < 0.0001, for both). The start of LV untwisting coincided with the beginning of relaxation and preceded suction-aided filling resulting from elastic recoil. Untwisting rate may be a useful marker of diastolic function or even serve as a therapeutic target for improving diastolic function.

User-initialized active contour segmentation and golden-angle real-time cardiovascular magnetic resonance enable accurate assessment of LV function in patients with sinus rhythm and arrhythmias.

PubMed

Contijoch, Francisco; Witschey, Walter R T; Rogers, Kelly; Rears, Hannah; Hansen, Michael; Yushkevich, Paul; Gorman, Joseph; Gorman, Robert C; Han, Yuchi

2015-05-21

Data obtained during arrhythmia is retained in real-time cardiovascular magnetic resonance (rt-CMR), but there is limited and inconsistent evidence to show that rt-CMR can accurately assess beat-to-beat variation in left ventricular (LV) function or during an arrhythmia. Multi-slice, short axis cine and real-time golden-angle radial CMR data was collected in 22 clinical patients (18 in sinus rhythm and 4 patients with arrhythmia). A user-initialized active contour segmentation (ACS) software was validated via comparison to manual segmentation on clinically accepted software. For each image in the 2D acquisitions, slice volume was calculated and global LV volumes were estimated via summation across the LV using multiple slices. Real-time imaging data was reconstructed using different image exposure times and frame rates to evaluate the effect of temporal resolution on measured function in each slice via ACS. Finally, global volumetric function of ectopic and non-ectopic beats was measured using ACS in patients with arrhythmias. ACS provides global LV volume measurements that are not significantly different from manual quantification of retrospectively gated cine images in sinus rhythm patients. With an exposure time of 95.2 ms and a frame rate of > 89 frames per second, golden-angle real-time imaging accurately captures hemodynamic function over a range of patient heart rates. In four patients with frequent ectopic contractions, initial quantification of the impact of ectopic beats on hemodynamic function was demonstrated. User-initialized active contours and golden-angle real-time radial CMR can be used to determine time-varying LV function in patients. These methods will be very useful for the assessment of LV function in patients with frequent arrhythmias.

Molecular characterization of Pacific white shrimp (Litopenaeus vannamei) sodium bicarbonate cotransporter (NBC) and its role in response to pH stress.

PubMed

Cai, Yi-Ming; Chen, Ting; Ren, Chun-Hua; Huang, Wen; Jiang, Xiao; Gao, Yan; Huo, Da; Hu, Chao-Qun

2017-05-01

The sodium bicarbonate cotransporter (NBC) is an integral membrane ion transporter that can transport HCO 3 - (or a related species, such as CO 3 2- ) across the plasma membrane. Previous researches revealed that NBC might play an important role in the regulation of intracellular pH in vertebrates. In the present study, an NBC cDNA was identified from Pacific white shrimp (Litopenaeus vannamei) and designated as Lv-NBC. The full-length Lv-NBC cDNA is 4479 bp in size, containing a 5'-untranslated region (UTR) of 59 bp, a 3'-UTR of 835 bp and an open reading frame (ORF) of 3585 bp that encodes a protein of 1194 amino acids with a deduced molecular weight of 134.34 kDa. The Lv-NBC protein contains two functional domains (Band_3_cyto and HCO3_cotransp) and twelve transmembrane (TM) domains. Expression of the Lv-NBC mRNA was ubiquitously detected in all selected tissues, with the highest level in the gill. By in situ hybridization (ISH) with Digoxigenin-labeled probe, the Lv-NBC positive cells were shown mainly located in the secondary gill filaments. After low or high pH challenge, the transcript levels of Lv-NBC in the gill were found to be up-regulated. After knockdown of the Lv-NBC level by siRNA, the mortality of shrimp significantly increased under pH stress. Our study, as a whole, may provide evidences for the role of NBC in shrimp responding to pH stress, and give a new insight of the acid/base homeostasis mechanism in crustaceans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exercise training improves cardiac function in infarcted rabbits: involvement of autophagic function and fatty acid utilization.

PubMed

Chen, Ching-Yi; Hsu, Hsiu-Ching; Lee, Bai-Chin; Lin, Hung-Ju; Chen, Ying-Hsien; Huang, Hui-Chun; Ho, Yi-Lwun; Chen, Ming-Fong

2010-04-01

To explore whether exercise can improve cardiac function in a post-myocardial infarction (MI) rabbit model and to determine contributing factors in the left ventricle (LV). Adult male New Zealand White rabbits (2.5-3 kg) underwent MI by ligation of the left anterior descending coronary artery. For 8 weeks after surgery, sham-operated, and post-MI rabbits were housed under sedentary conditions or assigned to a 4-week treadmill exercise protocol at a speed of 1.0 km/h for 30 min 5 days per week, then sacrificed. The non-infarcted region of the LV was harvested for further analysis. MI decreased left ventricular ejection fraction (LVEF) and increased thiobarbituric acid reactive substances (TBARS) generation in the LV. Exercise improved the cardiac function of MI rabbits. Left ventricular LC3II/LC3I (microtubule-associated protein light chain 3) in the MI group was 2.1-fold higher than that of the sham group, exercise significantly decreased LC3II/LC3I in the MI group. MI down-regulated the expression of heart-type fatty acid binding protein (h-FABP), and exercise up-regulated h-FABP. In addition, LVEF had a significantly positive correlation with h-FABP and a negative correlation with LC3II/LC3I. Exercise induced change in autophagic function and fatty acid utilization may contribute to the improvement in ventricular function in the infarcted heart.

Cardiac and peripheral adjustments induced by early exercise training intervention were associated with autonomic improvement in infarcted rats: role in functional capacity and mortality.

PubMed

Jorge, Luciana; Rodrigues, Bruno; Rosa, Kaleizu Teodoro; Malfitano, Christiane; Loureiro, Tatiana Carolina Alba; Medeiros, Alessandra; Curi, Rui; Brum, Patricia Chakur; Lacchini, Silvia; Montano, Nicola; De Angelis, Kátia; Irigoyen, Maria-Cláudia

2011-04-01

To test the effects of early exercise training (ET) on left ventricular (LV) and autonomic functions, haemodynamics, tissues blood flows (BFs), maximal oxygen consumption (VO(2) max), and mortality after myocardial infarction (MI) in rats. Male Wistar rats were divided into: control (C), sedentary-infarcted (SI), and trained-infarcted (TI). One week after MI, TI group underwent an ET protocol (90 days, 50-70% VO(2) max). Left ventricular function was evaluated non-invasively and invasively. Baroreflex sensitivity, heart rate variability, and pulse interval were measured. Cardiac output (CO) and regional BFs were determined using coloured microspheres. Infarcted area was reduced in TI (19 ± 6%) compared with SI (34 ± 5%) after ET. Exercise training improved the LV and autonomic functions, the CO and regional BF changes induced by MI, as well as increased SERCA2 expression and mRNA vascular endothelial growth factor levels. These changes brought about by ET resulted in mortality rate reduction in the TI (13%) group compared with the SI (54%) group. Early aerobic ET reduced cardiac and peripheral dysfunctions and preserved cardiovascular autonomic control after MI in trained rats. Consequently, these ET-induced changes resulted in improved functional capacity and survival after MI.

Association of left ventricular structural and functional abnormalities with aortic and brachial blood pressure variability in hypertensive patients: the SAFAR study.

PubMed

Chi, C; Yu, S-K; Auckle, R; Argyris, A A; Nasothimiou, E; Tountas, C; Aissopou, E; Blacher, J; Safar, M E; Sfikakis, P P; Zhang, Y; Protogerou, A D

2017-10-01

Both brachial blood pressure (BP) level and its variability (BPV) significantly associate with left ventricular (LV) structure and function. Recent studies indicate that aortic BP is superior to brachial BP in the association with LV abnormalities. However, it remains unknown whether aortic BPV better associate with LV structural and functional abnormalities. We therefore aimed to investigate and compare aortic versus brachial BPV, in terms of the identification of LV abnormalities. Two hundred and three participants who underwent echocardiography were included in this study. Twenty-four-hour aortic and brachial ambulatory BP was measured simultaneously by a validated BP monitor (Mobil-O-Graph, Stolberg, Germany) and BPV was calculated with validated formulae. LV mass and LV diastolic dysfunction (LVDD) were evaluated by echocardiography. The prevalence of LV hypertrophy (LVH) and LVDD increased significantly with BPV indices (P⩽0.04) in trend tests. After adjustment to potential confounders, only aortic average real variability (ARV), but not brachial ARV or weighted s.d. (wSD, neither aortic nor brachial) significantly associated with LV mass index (P=0.02). Similar results were observed in logistic regression. After adjustment, only aortic ARV significantly associated with LVH (odds ratio (OR) and 95% confidence interval (CI): 2.28 (1.08, 4.82)). As for LVDD, neither the brachial nor the aortic 24-hour wSD, but the aortic and brachial ARV, associated with LVDD significantly, with OR=2.28 (95% CI: (1.03, 5.02)) and OR=2.36 (95% CI: (1.10, 5.05)), respectively. In summary, aortic BPV, especially aortic ARV, seems to be superior to brachial BPV in the association of LV structural and functional abnormalities.

Analysis on the expression and function of syndecan in the Pacific white shrimp Litopenaeus vannamei.

PubMed

Yang, Hui; Li, Shihao; Li, Fuhua; Wen, Rong; Xiang, Jianhai

2015-08-01

Syndecan is considered to be a multifunctional protein which functions as a cell surface receptor involved in cell adhesion, migration, cytoskeleton organization and differentiation. Previous bioinformatic analysis has revealed that syndecan in shrimp might interact with white spot syndrome virus (WSSV). In the present study, we experimentally studied the function of syndecan in shrimp immunity. The syndecan from Litopenaeus vannamei (LvSDC) was cloned and analyzed. The full-length cDNA of LvSDC was 1005 bp, consisting of 59 bp 5'-UTR, 253 bp 3'-UTR, and 693 bp open reading frame encoding 230 amino acids. LvSDC consisted of an extracellular domain (ED), a transmembrane domain (TM) and a cytoplasmic domain (CD). TM and CD shared high similarities with those of syndecan proteins from other species. LvSDC was ubiquitously expressed in all tested tissues, with the highest level in Oka. After WSSV challenge, the transcription level of LvSDC in Oka was apparently up-regulated. Recombinant LvSDC protein and its rabbit polyclonal antibody were prepared for detecting the location of LvSDC in hemocytes using immunocytochemistry approach. Data showed that LvSDC mainly located at the cell membrane and the cytoplasm of hemocytes. After silencing of LvSDC with siRNA, the WSSV copy numbers and mortality of shrimp after WSSV infection were both significantly decreased. These data provide useful information for understanding the immune mechanism of shrimp to WSSV infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Left Ventricular Architecture, Long-Term Reverse Remodeling, and Clinical Outcome in Mild Heart Failure With Cardiac Resynchronization: Results From the REVERSE Trial.

PubMed

St John Sutton, Martin; Linde, Cecilia; Gold, Michael R; Abraham, William T; Ghio, Stefano; Cerkvenik, Jeffrey; Daubert, Jean-Claude

2017-03-01

This study sought to determine the effects of abnormal left ventricular (LV) architecture on cardiac remodeling and clinical outcomes in mild heart failure (HF). Cardiac resynchronization therapy (CRT) is an established treatment for HF that improves survival in part by favorably remodeling LV architecture. LV shape is a dynamic component of LV architecture on which contractile function depends. Transthoracic 2-dimensional echocardiography was used to quantify changes in LV architecture over 5 years of follow-up of patients with mild HF from the REVERSE study. REVERSE was a prospective study of patients with large hearts (LV end-diastolic dimension ≥55 mm), LV ejection fraction <40%, and QRS duration >120 ms randomly assigned to CRT-ON (n = 419) and CRT-OFF (n = 191). CRT-OFF patients were excluded from this analysis. LV dimensions, volumes, mass index, and LV ejection fraction were calculated. LV architecture was assessed using the sphericity index, as follows: (LV end-diastolic volume)/(4/3 × π × r 3 ) × 100%. LV architecture improved over time and demonstrated significant associations between LV shape, age, sex, and echocardiography metrics. Changes in LV architecture were strongly correlated with changes in LV end-systolic volume index and LV end-diastolic volume index (both p < 0.0001). Sphericity index emerged as a predictor of death and HF hospitalization in spite of the low adverse event rate. A decrease in LV end-systolic volume index >15% occurred in more than two-thirds of patients, which indicates considerable reverse remodeling. We demonstrated that change in LV architecture in patients with mild HF with CRT is associated with structural and functional remodeling. Mean LV filling pressure was elevated, and the inability to lower it was an additional predictor of HF hospitalization or death. (Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction [REVERSE]; NCT00271154). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Abdominal obesity and structure and function of the heart in healthy male Koreans: The ARIRANG study.

PubMed

Son, Jung-Woo; Sung, Joong Kyung; Lee, Jun-Won; Youn, Young Jin; Ahn, Min-Soo; Ahn, Sung Gyun; Yoo, Byung-Su; Lee, Seung-Hwan; Yoon, Junghan; Koh, Sang Baek; Kim, Jang-Young

2016-09-01

Although central obesity is a more powerful predictor of cardiovascular disease (CVD) than general obesity, there is limited information on structural and functional changes of the heart in central obesity. Therefore, we evaluated the association between abdominal obesity and geometric and functional changes of the heart in healthy males. A total of 1460 healthy males aged 40 to 70 years without known CVD from the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population were included. All individuals underwent conventional 2-dimensional echocardiography and tissue Doppler imaging to measure left atrial (LA) and left ventricle (LV) geometry and function. Increasing tertiles of waist circumference (WC) were associated with stepwise increases in LA volume, LV end-diastolic dimension, LV mass to height, deceleration time of E wave, and lower E/A ratio (all P trends <0.001). In multivariable logistic regression models, the odds ratios for LA enlargement, LV hypertrophy, LV enlargement, and diastolic dysfunction comparing the upper tertile of WC (>89 cm) to the lowest tertile (<82 cm) were 2.81 (95% confidence interval [CI] 2.24-3.54), 3.65 (95% CI 2.54-5.26), 4.23 (95% CI 2.61-6.87), and 1.75 (95% CI 1.37-2.22), respectively. LV ejection fraction and relative wall thickness were not increased with increasing WC. The association between WC and LA enlargement, LV enlargement, and diastolic dysfunction persisted after stratification by body mass index tertiles. Central obesity may be a stronger predictor than general obesity of geometric and functional changes in the LV and LA.

A novel cardiac MR chamber volume model for mechanical dyssynchrony assessment

NASA Astrophysics Data System (ADS)

Song, Ting; Fung, Maggie; Stainsby, Jeffrey A.; Hood, Maureen N.; Ho, Vincent B.

2009-02-01

A novel cardiac chamber volume model is proposed for the assessment of left ventricular mechanical dyssynchrony. The tool is potentially useful for assessment of regional cardiac function and identification of mechanical dyssynchrony on MRI. Dyssynchrony results typically from a contraction delay between one or more individual left ventricular segments, which in turn leads to inefficient ventricular function and ultimately heart failure. Cardiac resynchronization therapy has emerged as an electrical treatment of choice for heart failure patients with dyssynchrony. Prior MRI techniques have relied on assessments of actual cardiac wall changes either using standard cine MR images or specialized pulse sequences. In this abstract, we detail a semi-automated method that evaluates dyssynchrony based on segmental volumetric analysis of the left ventricular (LV) chamber as illustrated on standard cine MR images. Twelve sectors each were chosen for the basal and mid-ventricular slices and 8 sectors were chosen for apical slices for a total of 32 sectors. For each slice (i.e. basal, mid and apical), a systolic dyssynchrony index (SDI) was measured. SDI, a parameter used for 3D echocardiographic analysis of dyssynchrony, was defined as the corrected standard deviation of the time at which minimal volume is reached in each sector. The SDI measurement of a healthy volunteer was 3.54%. In a patient with acute myocardial infarction, the SDI measurements 10.98%, 16.57% and 1.41% for basal, mid-ventricular and apical LV slices, respectively. Based on published 3D echocardiogram reference threshold values, the patient's SDI corresponds to moderate basal dysfunction, severe mid-ventricular dysfunction, and normal apical LV function, which were confirmed on echocardiography. The LV chamber segmental volume analysis model and SDI is feasible using standard cine MR data and may provide more reliable assessment of patients with dyssynchrony especially if the LV myocardium is thin or if the MR images have spatial resolution insufficient for proper resolution of wall thickness-features problematic for dyssynchrony assessment using existing MR techniques.

Left ventricular mass, geometry and function in diabetic patients affected by coronary artery disease.

PubMed

Maiello, Maria; Zito, Annapaola; Carbonara, Santa; Ciccone, Marco Matteo; Palmiero, Pasquale

2017-10-01

Coronary artery disease (CAD) is quite common among diabetic patients, our study goal is to detect the prevalence of left ventricular (LV) adverse changes in geometry, mass and diastolic function on diabetic, but not hypertensive patients, with coronary artery disease(CAD) and LV ejection fraction(LVEF)>45%, actually unknown, because of current guidelines that do not include echocardiographic assessment for follow up of diabetic patients. 665 consecutive diabetic patients (443 females, mean age 66±9years), performed a complete echocardiographic assessment according to current ASE echo-guidelines: diastolic dysfunction (DD), eccentric hypertrophy (EH), concentric hypertrophy (CH) and concentric remodeling (CR) of LV were reported. CAD was assessed only by reports of bypass surgery, angioplasty or patients hospitalized for acute myocardial infarction. 218 patients (32.8%) presented LV changes: LVDD 49 (7.4%), LVEH 68 (10.2%), LVDD and EH 46 (6.9%), LVDD and CH 36 (5.4%), LVDD and CR 19 (2.9%). 447 (67.2%) had no LV changes. 81 (12.1%) patients with CAD, presented: LVDD 17 (21%), LVEH 32 (39.5%), LVDD and EH 9 (11.1%), LVDD and CH 7 (8.6%), LVDD and CR 8 (9.9%), 8 (9.9%) had no LV adverse changes. There were among CAD patients, a significantly higher prevalence of LVDD (p<0.02), LV eccentric hypertrophy (EH) (p<0.05), DD and LVEH (p<0.04), DD and LV concentric hypertrophy(CH) (p<0.03) and DD and LV concentric remodeling (p<0.02), when compared with those patients without CAD. CAD is related to all different patterns of LV adverse changes in mass, geometry and diastolic function, with a significantly higher prevalence in our population of diabetic patients with normal systolic function. These changes however remain unrecognized until they undergo to a conventional echocardiographic assessment. We support this tool need to be included into future guidelines concerning follow-up of diabetic patients. Copyright © 2017 Elsevier Inc. All rights reserved.

Systolic and diastolic assessment by 3D-ASM segmentation of gated-SPECT Studies: a comparison with MRI

NASA Astrophysics Data System (ADS)

Tobon-Gomez, C.; Bijnens, B. H.; Huguet, M.; Sukno, F.; Moragas, G.; Frangi, A. F.

2009-02-01

Gated single photon emission tomography (gSPECT) is a well-established technique used routinely in clinical practice. It can be employed to evaluate global left ventricular (LV) function of a patient. The purpose of this study is to assess LV systolic and diastolic function from gSPECT datasets in comparison with cardiac magnetic resonance imaging (CMR) measurements. This is achieved by applying our recently implemented 3D active shape model (3D-ASM) segmentation approach for gSPECT studies. This methodology allows for generation of 3D LV meshes for all cardiac phases, providing volume time curves and filling rate curves. Both systolic and diastolic functional parameters can be derived from these curves for an assessment of patient condition even at early stages of LV dysfunction. Agreement of functional parameters, with respect to CMR measurements, were analyzed by means of Bland-Altman plots. The analysis included subjects presenting either LV hypertrophy, dilation or myocardial infarction.

Left ventricle segmentation via two-layer level sets with circular shape constraint.

PubMed

Yang, Cong; Wu, Weiguo; Su, Yuanqi; Zhang, Shaoxiang

2017-05-01

This paper proposes a circular shape constraint and a novel two-layer level set method for the segmentation of the left ventricle (LV) from short-axis magnetic resonance images without training any shape models. Since the shape of LV throughout the apex-base axis is close to a ring shape, we propose a circle fitting term in the level set framework to detect the endocardium. The circle fitting term imposes a penalty on the evolving contour from its fitting circle, and thereby handles quite well with issues in LV segmentation, especially the presence of outflow track in basal slices and the intensity overlap between TPM and the myocardium. To extract the whole myocardium, the circle fitting term is incorporated into two-layer level set method. The endocardium and epicardium are respectively represented by two specified level contours of the level set function, which are evolved by an edge-based and a region-based active contour model. The proposed method has been quantitatively validated on the public data set from MICCAI 2009 challenge on the LV segmentation. Experimental results and comparisons with state-of-the-art demonstrate the accuracy and robustness of our method. Copyright © 2017 Elsevier Inc. All rights reserved.

Non-Invasive Mapping of Intraventricular Flow Patterns in Patients Treated with Left Ventricular Assist Devices

NASA Astrophysics Data System (ADS)

Miramontes, Marissa; Rossini, Lorenzo; Braun, Oscar; Brambatti, Michela; Almeida, Shone; Mizeracki, Adam; Martinez-Legazpi, Pablo; Benito, Yolanda; Bermejo, Javier; Kahn, Andrew; Adler, Eric; Del Álamo, Juan C.

2017-11-01

In heart failure patients, left ventricular (LV) assist devices (LVADs) decrease mortality and improve quality of life. We hypothesize echo color Doppler velocimetry (echo-CDV), an echocardiographic flow mapping modality, can non-invasively characterize the effect of LVAD support, optimize the device, thereby decreasing the stoke rate present in these patients. We used echo-CDV to image LV flow at baseline LVAD speed and during a ramp test in LVAD patients (Heartmate II, N =10). We tracked diastolic vortices and mapped blood stasis and cumulative shear. Compared to dilated cardiomyopathy (DCM) patients without LVADs, the flow had a less prominent diastolic vortex ring, and transited directly from mitral valve to cannula. Residence time and shear were significantly lower compared to healthy controls and DCMs. Aortic regurgitation and a large LV vortex presence or a direct mitral jet towards the cannula affected blood stasis region location and size. Flow patterns, residence time and shear depended on LV geometry, valve function and LVAD speed in a patient specific manner. This new methodology could be used with standard echo, hemodynamics and clinical information to find the flow optimizing LAVD setting minimizing stasis for each patient.

Assessment of ventricular and left atrial mechanical functions, atrial electromechanical delay and P wave dispersion in patients with scleroderma.

PubMed

Aktoz, Meryem; Yilmaztepe, Mustafa; Tatli, Ersan; Turan, Fatma Nesrin; Umit, Elif G; Altun, Armagan

2011-01-01

The aim of this study was to investigate ventricular functions and left atrial (LA) mechanical functions, atrial electromechanical coupling, and P wave dispersion in scleroderma patients. Twenty-six patients with scleroderma and twenty-four controls were included. Left and right ventricular (LV and RV) functions were evaluated using conventional echocardiography and tissue Doppler imaging (TDI). LA volumes were measured using the biplane area- -length method and LA mechanical function parameters were calculated. Inter-intraatrial electromechanical delays were measured by TDI. P wave dispersion was calculated by 12-lead electrocardiograms. LV myocardial performance indices (MPI) and RV MPI were higher in patients with scleroderma (p = 0.000, p = 0.000, respectively) while LA passive emptying fraction was decreased and LA active emptying fraction was increased (p = 0.051, p = 0.000, respectively). P wave dispersion and inter-intraatrial electromechanical delay were significantly higher in patients with scleroderma (25 [10-60] vs 20 [0-30], p = 0.000, 16.50 [7.28-26.38] vs 9.44 [3.79-15.78] and 11.33 [4.88-16.06] vs 4.00 [0-12.90], p < 0.05, respectively). Interatrial electromechanical delay was negatively correlated with LV E wave, (p = 0.018). LV E wave was demonstrated to be a factor independent of the interatrial electromechanical delay (R² = = 0.270, b = -0.52, p = 0.013). This study showed that in scleroderma patients, global functions of LV, RV and mechanical functions of LA were impaired, intra-interatrial electromechanical delays were prolonged and P wave dispersion was higher. LV E wave was demonstrated to be a factor that is independent of the interatrial electromechanical delay. Reduced LV E wave may also give additional information on the process of risk stratification of atrial fibrillation.

Exercise reveals impairments in left ventricular systolic function in patients with metabolic syndrome

PubMed Central

Fournier, Sara B.; Reger, Brian L.; Donley, David A.; Bonner, Daniel E.; Warden, Bradford E.; Gharib, Wissam; Failinger, Conard F.; Olfert, Melissa D.; Frisbee, Jefferson C.; Olfert, I. Mark; Chantler, Paul D.

2013-01-01

MetS is the manifestation of a cluster of cardiovascular (CV) risk factors and is associated with a three-fold increase risk of CV morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to comprehensively examine LV and arterial responses to exercise in MetS individuals without diabetes and/or overt CVD compared to a healthy control population. CV function was characterized using Doppler echocardiography and gas exchange in MetS (n=27) vs. healthy controls (n=20) at rest and during peak exercise. At rest, MetS individuals displayed normal LV systolic function but reduced LV diastolic function vs. healthy controls. During peak exercise, individuals with MetS had impaired contractility; pump performance, and vasodilator reserve capacity vs. controls. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in MetS vs. controls. These findings possess clinical importance as they provide insight to the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of CV morbidity and mortality. PMID:24036595

Central adaptations in aerobic circuit versus walking/jogging trained cardiac patients.

PubMed

Goodman, L S; McKenzie, D C; Nath, C R; Schamberger, W; Taunton, J E; Ammann, W C

1995-06-01

This study was done to determine (a) whether in coronary artery disease (CAD) left ventricular (LV) adaptations differed after 6 months of walking/jogging (legs-only, LO) versus aerobic circuit training (arms and legs, AL) versus a control group, and (b) whether a transfer of fitness to the untrained arms in the LO group was related to superior LV adaptations. Peak oxygen uptake for arm and leg ergometry and for cycle ergometry using radionuclide cardiac angiography were performed before and after training. Leg and arm VO2peak increased significantly by 13% in the AL group, and by 13% and 7%, respectively, for the LO group. LV function was greater after training for the LO versus the AL group. Improvements in systolic and diastolic function and a speculated hypervolemia explain these LV adaptations. In CAD patients, walking/jogging produces greater LV function improvements versus circuit training, possibly due to differences in the exercised muscle mass.

Visceral adiposity and skeletal muscle mass are independently and synergistically associated with left ventricular structure and function: the Korean Genome and Epidemiology Study.

PubMed

Park, Juri; Kim, Nan Hee; Kim, Seong Hwan; Kim, Jin-Seok; Kim, Yong Hyun; Lim, Hong Euy; Kim, Eung Ju; Na, Jin Oh; Cho, Goo-Yeong; Baik, Inkyung; Kim, Doo Man; Choi, Dong Seop; Lee, Seung Ku; Shin, Chol

2014-10-20

Obesity and low muscle mass may coexist as age-related changes in body composition. We aimed to investigate the effect of visceral adiposity and skeletal muscle mass on left ventricular (LV) structure and function in the general population. A total of 1941 participants without known cardiovascular disease were enrolled from the Korean Genome and Epidemiology Study. Visceral fat area (VFA) was assessed by computed tomography. Appendicular skeletal muscle mass (ASM) was estimated by dual-energy X-ray absorptiometry and was used as a percentage of body weight (ASM/Wt). LV structure and function were assessed by tissue Doppler imaging (TDI) echocardiography. Across VFA tertiles, ASM increased, but ASM/Wt decreased (all P<0.001). In multivariate models adjusted for conventional cardiovascular risk factors, LV mass index and LV diastolic parameters, such as left atrial dimension, TDI Ea velocity, and E/Ea ratio, were significantly impaired as VFA increased. On the other hand, an increase in ASM/Wt was associated with a decrease in LV mass index and improvement of LV diastolic parameters. With regard to LV mass index and TDI Ea velocity, VFA and ASM/Wt showed synergistic effects (all P interaction<0.05). When both VFA and ASM/Wt were simultaneously included in the same model, both remained independent predictors of LV mass index and TDI Ea velocity. More visceral fat and less muscle mass are independently and synergistically associated with an increase in LV mass index and impairment of LV diastolic parameters. Further research is needed to explore the complex mechanisms underlying these associations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Diastolic Backward-Traveling Decompression (Suction) Wave Correlates With Simultaneously Acquired Indices of Diastolic Function and Is Reduced in Left Ventricular Stunning.

PubMed

Ladwiniec, Andrew; White, Paul A; Nijjer, Sukhjinder S; O'Sullivan, Michael; West, Nick E J; Davies, Justin E; Hoole, Stephen P

2016-09-01

Wave intensity analysis can distinguish proximal (propulsion) and distal (suction) influences on coronary blood flow and is purported to reflect myocardial performance and microvascular function. Quantifying the amplitude of the peak, backwards expansion wave (BEW) may have clinical utility. However, simultaneously acquired wave intensity analysis and left ventricular (LV) pressure-volume loop data, confirming the origin and effect of myocardial function on the BEW in humans, have not been previously reported. Patients with single-vessel left anterior descending coronary disease and normal ventricular function (n=13) were recruited prospectively. We simultaneously measured LV function with a conductance catheter and derived wave intensity analysis using a pressure-low velocity guidewire at baseline and again 30 minutes after a 1-minute coronary balloon occlusion. The peak BEW correlated with the indices of diastolic LV function: LV dP/dtmin (rs=-0.59; P=0.002) and τ (rs=-0.59; P=0.002), but not with systolic function. In 12 patients with paired measurements 30 minutes post balloon occlusion, LV dP/dtmax decreased from 1437.1±163.9 to 1299.4±152.9 mm Hg/s (median difference, -110.4 [-183.3 to -70.4]; P=0.015) and τ increased from 48.3±7.4 to 52.4±7.9 ms (difference, 4.1 [1.3-6.9]; P=0.01), but basal average peak coronary flow velocity was unchanged, indicating LV stunning post balloon occlusion. However, the peak BEW amplitude decreased from -9.95±5.45 W·m(-2)/s(2)×10(5) to -7.52±5.00 W·m(-2)/s(2)×10(5) (difference 2.43×10(5) [0.20×10(5) to 4.67×10(5); P=0.04]). Peak BEW assessed by coronary wave intensity analysis correlates with invasive indices of LV diastolic function and mirrors changes in LV diastolic function confirming the origin of the suction wave. This may have implications for physiological lesion assessment after percutaneous coronary intervention. URL: http://www.isrctn.org. Unique identifier: ISRCTN42864201. © 2016 American Heart Association, Inc.

Cardiac structure and function in Cushing's syndrome: a cardiac magnetic resonance imaging study.

PubMed

Kamenický, Peter; Redheuil, Alban; Roux, Charles; Salenave, Sylvie; Kachenoura, Nadjia; Raissouni, Zainab; Macron, Laurent; Guignat, Laurence; Jublanc, Christel; Azarine, Arshid; Brailly, Sylvie; Young, Jacques; Mousseaux, Elie; Chanson, Philippe

2014-11-01

Patients with Cushing's syndrome have left ventricular (LV) hypertrophy and dysfunction on echocardiography, but echo-based measurements may have limited accuracy in obese patients. No data are available on right ventricular (RV) and left atrial (LA) size and function in these patients. The objective of the study was to evaluate LV, RV, and LA structure and function in patients with Cushing's syndrome by means of cardiac magnetic resonance, currently the reference modality in assessment of cardiac geometry and function. Eighteen patients with active Cushing's syndrome and 18 volunteers matched for age, sex, and body mass index were studied by cardiac magnetic resonance. The imaging was repeated in the patients 6 months (range 2-12 mo) after the treatment of hypercortisolism. Compared with controls, patients with Cushing's syndrome had lower LV, RV, and LA ejection fractions (P < .001 for all) and increased end-diastolic LV segmental thickness (P < .001). Treatment of hypercortisolism was associated with an improvement in ventricular and atrial systolic performance, as reflected by a 15% increase in the LV ejection fraction (P = .029), a 45% increase in the LA ejection fraction (P < .001), and an 11% increase in the RV ejection fraction (P = NS). After treatment, the LV mass index and end-diastolic LV mass to volume ratio decreased by 17% (P < .001) and 10% (P = .002), respectively. None of the patients had late gadolinium myocardial enhancement. Cushing's syndrome is associated with subclinical biventricular and LA systolic dysfunctions that are reversible after treatment. Despite skeletal muscle atrophy, Cushing's syndrome patients have an increased LV mass, reversible upon correction of hypercortisolism.

Left ventricular functional parameters by gated SPECT myocardial perfusion imaging in a Latin American country.

PubMed

Kapitan, Miguel; Beltran, Alvaro; Beretta, Mario; Mut, Fernando

2018-04-01

There is paucity of data on left ventricular (LV) functional parameters using gated SPECT myocardial perfusion imaging (MPI) from the Latin American region. This study provides detailed information in low-risk patients both at rest and during exercise. We studied 90 patients (50 men) with a very low likelihood of coronary artery disease. Gated-SPECT MPI was performed with Tc-99m MIBI using a 2-day protocol, with 16 frames/R-R cycle. The LV ejection fraction and volumes were not different between the rest and post-stress images. LVEF was 68 ± 7% post-stress and 70 ± 7% at rest in women, and 62 ± 7% and 63 ± 7%, respectively, in men (P = .19, .26). LV volumes were larger in men than women (P < .01). There were no differences in most variables obtained at rest or post-stress. Transient ischemic dilatation was similar, with upper limits of 1.20 and 1.19 in women and men, respectively (P = NS). These data could prove helpful for the interpretation of gated SPECT MPI data in Latin America using identical protocol as used in this study.

Citrus psorosis virus RNA 1 is of negative polarity and potentially encodes in its complementary strand a 24K protein of unknown function and 280K putative RNA dependent RNA polymerase.

PubMed

Naum-Onganía, Gabriela; Gago-Zachert, Selma; Peña, Eduardo; Grau, Oscar; Garcia, Maria Laura

2003-10-01

Citrus psorosis virus (CPsV), the type member of genus Ophiovirus, has three genomic RNAs. Complete sequencing of CPsV RNA 1 revealed a size of 8184 nucleotides and Northern blot hybridization with chain specific probes showed that its non-coding strand is preferentially encapsidated. The complementary strand of RNA 1 contains two open reading frames (ORFs) separated by a 109-nt intergenic region, one located near the 5'-end potentially encoding a 24K protein of unknown function, and another of 280K containing the core polymerase motifs characteristic of viral RNA-dependent RNA polymerases (RdRp). Comparison of the core RdRp motifs of negative-stranded RNA viruses, supports grouping CPsV, Ranunculus white mottle virus (RWMV) and Mirafiori lettuce virus (MiLV) within the same genus (Ophiovirus), constituting a monophyletic group separated from all other negative-stranded RNA viruses. Furthermore, RNAs 1 of MiLV, CPsV and RWMV are similar in size and those of MiLV and CPsV also in genomic organization and sequence.

Quantitative Differentiation of LV Myocardium with and without Layer-Specific Fibrosis Using MRI in Hypertrophic Cardiomyopathy and Layer-Specific Strain TTE Analysis.

PubMed

Funabashi, Nobusada; Takaoka, Hiroyuki; Ozawa, Koya; Kamata, Tomoko; Uehara, Masae; Komuro, Issei; Kobayashi, Yoshio

2018-05-30

To achieve further risk stratification in hypertrophic cardiomyopathy (HCM) patients, we localized and quantified layer-specific LVM fibrosis on MRI in HCM patients using regional layer-specific peak longitudinal strain (PLS) and peak circumferential strain (PCS) in LV myocardium (LVM) on speckle tracking transthoracic echocardiography (TTE). A total of 18 HCM patients (14 males; 58 ± 17 years) underwent 1.5T-MRI and TTE. PLS and PCS in each layer of the LVM (endocardium, epicardium, and whole-layer myocardium) were calculated for 17 AHA-defined lesions. MRI assessment showed that fibrosis was classified as endocardial, epicardial, or whole-layer (= either or both of these). Regional PLS was smaller in fibrotic endocardial lesions than in non-fibrotic endocardial lesions (P = 0.004). To detect LV endocardial lesions with fibrosis, ROC curves of regional PLS revealed an area under the curve (AUC) of 0.609 and a best cut-off point of 13.5%, with sensitivity of 65.3% and specificity of 54.3%. Regional PLS was also smaller in fibrotic epicardial lesions than in non-fibrotic epicardial lesions (P < 0.001). To detect LV epicardial lesions with fibrosis, ROC curves of PLS revealed an AUC of 0.684 and a best cut-off point of 9.5%, with sensitivity of 73.5% and specificity of 55.5%. Using whole-layer myocardium analysis, PLS was smaller in fibrotic lesions than in non-fibrotic lesions (P < 0.001). To detect whole-layer LV lesions with fibrosis, ROC curves of regional PLS revealed an AUC of 0.674 and a best cut-off point of 12.5%, with sensitivity of 79.0% and specificity of 50.7%. There were no significant differences in PCS of LV myocardium (endocardium, epicardium, and whole-layer) between fibrotic and non-fibrotic lesions. Quantitative regional PLS but not PCS in LV endocardium, epicardium, and whole-layer myocardium provides useful non-invasive information for layer-specific localization of fibrosis in HCM patients.

Transient severe left ventricular dysfunction following percutaneous patent ductus arteriosus closure in an adult with bicuspid aortic valve: A case report

PubMed Central

HWANG, HUI-JEONG; YOON, KYUNG LIM; SOHN, IL SUK

2016-01-01

The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans. PMID:26998021

Transient severe left ventricular dysfunction following percutaneous patent ductus arteriosus closure in an adult with bicuspid aortic valve: A case report.

PubMed

Hwang, Hui-Jeong; Yoon, Kyung Lim; Sohn, Il Suk

2016-03-01

The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans.

Association between urine aldosterone and diastolic function in patients with primary aldosteronism and essential hypertension.

PubMed

Chang, Yi-Yao; Lee, Hsiu-Hao; Hung, Chi-Sheng; Wu, Xue-Ming; Lee, Jen-Kuang; Wang, Shuo-Meng; Liao, Min-Tsun; Chen, Ying-Hsien; Wu, Vin-Cent; Wu, Kwan-Dun; Lin, Yen-Hung

2014-09-01

To investigate the association between aldosterone and cardiac diastolic dysfunction. We prospectively enrolled 20 patients with primary aldosteronism (PA) and 22 patients with essential hypertension (EH). Plasma aldosterone concentration, plasma renin activity, and 24-h urine aldosterone level were measured. Echocardiography, including tissue Doppler image recordings, was performed. PA patients had a significantly higher left ventricular (LV) mass index and worse LV diastolic function than those in EH patients. Among various measures of aldosterone, log-transformed 24-h urine aldosterone level had the most consistent correlation with diastolic function. Aldosterone is strongly associated with LV diastolic dysfunction. Twenty-four hour urine aldosterone is a good indicator to evaluate the impact of aldosterone on LV diastolic function. Copyright © 2014. Published by Elsevier Inc.

Subclinical atherosclerosis in obese adolescents with normal left ventricular function.

PubMed

Abdel-Wahab, Amina M; Atwa, Hoda A; El-Eraky, Azza Z; El-Aziz, Mohamed A

2011-09-01

To assess the impact of obesity on carotid intima media thickness and left ventricular (LV) mass in obese adolescents. The study included 52 obese adolescents (mean age 14.16+/-2.64 years) and 52 healthy adolescents who served as a control group (mean age 12+/-2.3 years), who were attended the outpatient clinic at Suez Canal University Hospital, Ismailia, Egypt. The study population was submitted for medical history, clinical examination, laboratory investigations (fasting blood sugar and lipid profile), and echocardiographic examination of LV mass and dimensions. Assessment of carotid intima-media thickness was carried out by using carotid duplex. All children had normal LV function. Obese adolescents had a significant increase in total cholesterol, triglyceride, LDL-C, and low HDL-C compared to the control group. Also, there was a significant increase in blood pressure, carotid intima media thickness, LV mass, and LV mass index. There was a significant correlation between BMI and dyslipidemia, blood pressure, carotid intima/media thickness, LV mass, and posterior wall thickness. Carotid intima-media thickness had a significant correlation with increased LDL-C and low HDL-C, blood pressure, LV mass, and posterior wall thickness. Obesity in childhood and adolescents is associated with subclinical atherosclerosis. Although obese children had no LV dysfunction, yet there are LV structure changes.

Saxagliptin and Tadalafil Differentially Alter Cyclic Guanosine Monophosphate (cGMP) Signaling and Left Ventricular Function in Aortic-Banded Mini-Swine.

PubMed

Hiemstra, Jessica A; Lee, Dong I; Chakir, Khalid; Gutiérrez-Aguilar, Manuel; Marshall, Kurt D; Zgoda, Pamela J; Cruz Rivera, Noelany; Dozier, Daniel G; Ferguson, Brian S; Heublein, Denise M; Burnett, John C; Scherf, Carolin; Ivey, Jan R; Minervini, Gianmaria; McDonald, Kerry S; Baines, Christopher P; Krenz, Maike; Domeier, Timothy L; Emter, Craig A

2016-04-20

Cyclic guanosine monophosphate-protein kinase G-phosphodiesterase 5 signaling may be disturbed in heart failure (HF) with preserved ejection fraction, contributing to cardiac remodeling and dysfunction. The purpose of this study was to manipulate cyclic guanosine monophosphate signaling using the dipeptidyl-peptidase 4 inhibitor saxagliptin and phosphodiesterase 5 inhibitor tadalafil. We hypothesized that preservation of cyclic guanosine monophosphate cGMP signaling would attenuate pathological cardiac remodeling and improve left ventricular (LV) function. We assessed LV hypertrophy and function at the organ and cellular level in aortic-banded pigs. Concentric hypertrophy was equal in all groups, but LV collagen deposition was increased in only HF animals. Prevention of fibrotic remodeling by saxagliptin and tadalafil was correlated with neuropeptide Y plasma levels. Saxagliptin better preserved integrated LV systolic and diastolic function by maintaining normal LV chamber volumes and contractility (end-systolic pressure-volume relationship, preload recruitable SW) while preventing changes to early/late diastolic longitudinal strain rate. Function was similar to the HF group in tadalafil-treated animals including increased LV contractility, reduced chamber volume, and decreased longitudinal, circumferential, and radial mechanics. Saxagliptin and tadalafil prevented a negative cardiomyocyte shortening-frequency relationship observed in HF animals. Saxagliptin increased phosphodiesterase 5 activity while tadalafil increased cyclic guanosine monophosphate levels; however, neither drug increased downstream PKG activity. Early mitochondrial dysfunction, evident as decreased calcium-retention capacity and Complex II-dependent respiratory control, was present in both HF and tadalafil-treated animals. Both saxagliptin and tadalafil prevented increased LV collagen deposition in a manner related to the attenuation of increased plasma neuropeptide Y levels. Saxagliptin appears superior for treating heart failure with preserved ejection fraction, considering its comprehensive effects on integrated LV systolic and diastolic function. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Left ventricular functions in children with newly diagnosed Graves' disease. A single-center study from Upper Egypt.

PubMed

Metwalley, Kotb Abbass; Farghaly, Hekma Saad; Abdelhamid, Abdelrahman

2018-01-01

This study aimed to evaluate the left ventricular (LV) functions in a cohort of children with Graves' disease (GD). This is a cross-sectional case-control study. It included 36 children with GD and 36 healthy children matched for age and gender. Thyroid hormones (TSH, FT4, and FT3) and anti-thyroid autoantibodies [anti-thyroid peroxidase (anti-TPO), thyrotropin receptor (TRAbs), and thyroglobulin antibodies] were measured. Conventional and tissue Doppler imaging (TDI) echocardiographies were used to assess left ventricular systolic and diastolic functions. LV mass index (LVMI) and myocardial performance index (MPI) were also measured. Compared to healthy children, conventional echocardiography of patients with GD revealed higher LVMI (P = 0.001) indicating LV hypertrophy but normal LV functions while TDI revealed lower Em/Am ratio indicating LV diastolic dysfunction (P = 0.001). Significant correlations were reported between FT4 with LVMI (P = 0.05), Em/Am (P = 0.01), and MPI (P = 0.01). In multivariate analysis, a positive correlation was identified between FT4 with MPI (OR = 1.17; 95% CI = 1.09-1.15; P = 0.001). Children with newly diagnosed GD may have significant subclinical changes in LV structure and function (diastolic and global). TDI is more sensitive than conventional Doppler in detecting LV dysfunction. These findings highlight the importance of early monitoring of children with GD for left ventricular mass index and diastolic function. What is Known: • There is an increased risk for cardiac abnormalities in children with Graves' disease (GD). • Limited studies assessed left ventricular function in patients with GD. What is New: • Children with newly diagnosed GD may have significant subclinical changes in left ventricular structure and functions. • Children with newly diagnosed GD should be monitored for left ventricular mass index and diastolic function.

Comparison of left ventricular diastolic function in obstructive hypertrophic cardiomyopathy in patients undergoing percutaneous septal alcohol ablation versus surgical myotomy/myectomy

NASA Technical Reports Server (NTRS)

Sitges, Marta; Shiota, Takahiro; Lever, Harry M.; Qin, Jian Xin; Bauer, Fabrice; Drinko, Jeannie K.; Agler, Deborah A.; Martin, Maureen G.; Greenberg, Neil L.; Smedira, Nicholas G.;

Temperature-dependent inotropic and lusitropic indices based on half-logistic time constants for four segmental phases in isovolumic left ventricular pressure-time curve in excised, cross-circulated canine heart.

PubMed

Mizuno, Ju; Mohri, Satoshi; Yokoyama, Takeshi; Otsuji, Mikiya; Arita, Hideko; Hanaoka, Kazuo

2017-02-01

Varying temperature affects cardiac systolic and diastolic function and the left ventricular (LV) pressure-time curve (PTC) waveform that includes information about LV inotropism and lusitropism. Our proposed half-logistic (h-L) time constants obtained by fitting using h-L functions for four segmental phases (Phases I-IV) in the isovolumic LV PTC are more useful indices for estimating LV inotropism and lusitropism during contraction and relaxation periods than the mono-exponential (m-E) time constants at normal temperature. In this study, we investigated whether the superiority of the goodness of h-L fits remained even at hypothermia and hyperthermia. Phases I-IV in the isovolumic LV PTCs in eight excised, cross-circulated canine hearts at 33, 36, and 38 °C were analyzed using h-L and m-E functions and the least-squares method. The h-L and m-E time constants for Phases I-IV significantly shortened with increasing temperature. Curve fitting using h-L functions was significantly better than that using m-E functions for Phases I-IV at all temperatures. Therefore, the superiority of the goodness of h-L fit vs. m-E fit remained at all temperatures. As LV inotropic and lusitropic indices, temperature-dependent h-L time constants could be more useful than m-E time constants for Phases I-IV.

Incidence of persistent viraemia and latent feline leukaemia virus infection in cats with lymphoma.

PubMed

Stützer, Bianca; Simon, Karin; Lutz, Hans; Majzoub, Monir; Hermanns, Walter; Hirschberger, Johannes; Sauter-Louis, Carola; Hartmann, Katrin

2011-02-01

In the past, feline leukaemia virus (FeLV) infection, and also latent FeLV infection, were commonly associated with lymphoma and leukaemia. In this study, the prevalence of FeLV provirus in tumour tissue and bone marrow in FeLV antigen-negative cats with these tumours was assessed. Seventy-seven diseased cats were surveyed (61 antigen-negative, 16 antigen-positive). Blood, bone marrow, and tumour samples were investigated by two polymerase chain reaction (PCR) assays detecting deoxyribonucleic acid (DNA) sequences of the long terminal repeats (LTR) and the envelope (env) region of the FeLV genome. Immunohistochemistry (IHC) was performed in bone marrow and tumour tissue. None of the antigen-negative cats with lymphoma was detectably infected with latent FeLV. The prevalence of FeLV viraemia in cats with lymphoma was 20.8%. This suggests that causes other than FeLV play a role in tumorigenesis, and that latent FeLV infection is unlikely to be responsible for most feline lymphomas and leukaemias. Copyright © 2010. Published by Elsevier Ltd.

Initial clinical experience of real-time three-dimensional echocardiography in patients with ischemic and idiopathic dilated cardiomyopathy

NASA Technical Reports Server (NTRS)

Shiota, T.; McCarthy, P. M.; White, R. D.; Qin, J. X.; Greenberg, N. L.; Flamm, S. D.; Wong, J.; Thomas, J. D.

1999-01-01

The geometry of the left ventricle in patients with cardiomyopathy is often sub-optimal for 2-dimensional ultrasound when assessing left ventricular (LV) function and localized abnormalities such as a ventricular aneurysm. The aim of this study was to report the initial experience of real-time 3-D echocardiography for evaluating patients with cardiomyopathy. A total of 34 patients were evaluated with the real-time 3D method in the operating room (n = 15) and in the echocardiographic laboratory (n = 19). Thirteen of 28 patients with cardiomyopathy and 6 other subjects with normal LV function were evaluated by both real-time 3-D echocardiography and magnetic resonance imaging (MRI) for obtaining LV volumes and ejection fractions for comparison. There were close relations and agreements for LV volumes (r = 0.98, p <0.0001, mean difference = -15 +/- 81 ml) and ejection fractions (r = 0.97, p <0.0001, mean difference = 0.001 +/- 0.04) between the real-time 3D method and MRI when 3 cardiomyopathy cases with marked LV dilatation (LV end-diastolic volume >450 ml by MRI) were excluded. In these 3 patients, 3D echocardiography significantly underestimated the LV volumes due to difficulties with imaging the entire LV in a 60 degrees x 60 degrees pyramidal volume. The new real-time 3D echocardiography is feasible in patients with cardiomyopathy and may provide a faster and lower cost alternative to MRI for evaluating cardiac function in patients.

Exercise reveals impairments in left ventricular systolic function in patients with metabolic syndrome.

PubMed

Fournier, Sara B; Reger, Brian L; Donley, David A; Bonner, Daniel E; Warden, Bradford E; Gharib, Wissam; Failinger, Conard F; Olfert, Melissa D; Frisbee, Jefferson C; Olfert, I Mark; Chantler, Paul D

2014-01-01

Metabolic syndrome (MetS) is the manifestation of a cluster of cardiovascular risk factors and is associated with a threefold increase in the risk of cardiovascular morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to examine comprehensively the LV and arterial responses to exercise in individuals with MetS without diabetes and/or overt cardiovascular disease in comparison to a healthy control population. Cardiovascular function was characterized using Doppler echocardiography and gas exchange in individuals with MetS (n = 27) versus healthy control subjects (n = 20) at rest and during peak exercise. At rest, individuals with MetS displayed normal LV systolic function but reduced LV diastolic function compared with healthy control subjects. During peak exercise, individuals with MetS had impaired contractility, pump performance and vasodilator reserve capacity versus control subjects. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in individuals with MetS versus control subjects. These findings are of clinical importance, because they provide insight into the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of cardiovascular morbidity and mortality.

Left ventricular long-axis function in treated haemochromatosis.

PubMed

Davidsen, Einar Skulstad; Hervig, Tor; Omvik, Per; Gerdts, Eva

2009-03-01

We recently demonstrated reduced exercise capacity in treated genetic haemochromatosis, in spite of normal radial left ventricular (LV) systolic function assessed by 2-dimensional echocardiography at rest. It remains unknown if haemochromatosis-related impairment of LV long-axis function can be demonstrated also at rest. LV long-axis function was assessed by echocardiography including spectral tissue Doppler of systolic (S') and early (E') diastolic velocities in 105 treated haemochromatosis patients and 50 controls. Patients had higher body mass index, systolic atrioventricular excursion, and smaller LV end-systolic diameter (all P < 0.05). Other conventional echocardiographic variables did not differ. S' was normal in both groups, though significantly higher among the patients (11.1 vs. 9.9 cm/s, P < 0.001). In multiple regression analysis, higher S' was associated with having haemochromatosis, independently of significant contributions from higher atrioventricular excursion and LV length, and lower body mass index and E/E'-ratio (multiple R(2) = 0.44, P < 0.001). E' did not differ between patients and controls. However, in multivariate analysis lower E' was associated with having haemochromatosis independently of significant contributions from higher age and diastolic blood pressure, and lower transmitral E and end-diastolic LV length (multiple R(2) = 0.57, P < 0.001). The long-axis function in the haemochromatosis group was normal. Still haemochromatosis, even in this group of patients treated with regular phlebotomy, influenced both systolic and early diastolic long-axis function, and was associated with higher atrioventricular excursion and S', and with lower E'.

Cardiac Structure and Function in Cushing's Syndrome: A Cardiac Magnetic Resonance Imaging Study

PubMed Central

Roux, Charles; Salenave, Sylvie; Kachenoura, Nadjia; Raissouni, Zainab; Macron, Laurent; Guignat, Laurence; Jublanc, Christel; Azarine, Arshid; Brailly, Sylvie; Young, Jacques; Mousseaux, Elie; Chanson, Philippe

2014-01-01

Background: Patients with Cushing's syndrome have left ventricular (LV) hypertrophy and dysfunction on echocardiography, but echo-based measurements may have limited accuracy in obese patients. No data are available on right ventricular (RV) and left atrial (LA) size and function in these patients. Objectives: The objective of the study was to evaluate LV, RV, and LA structure and function in patients with Cushing's syndrome by means of cardiac magnetic resonance, currently the reference modality in assessment of cardiac geometry and function. Methods: Eighteen patients with active Cushing's syndrome and 18 volunteers matched for age, sex, and body mass index were studied by cardiac magnetic resonance. The imaging was repeated in the patients 6 months (range 2–12 mo) after the treatment of hypercortisolism. Results: Compared with controls, patients with Cushing's syndrome had lower LV, RV, and LA ejection fractions (P < .001 for all) and increased end-diastolic LV segmental thickness (P < .001). Treatment of hypercortisolism was associated with an improvement in ventricular and atrial systolic performance, as reflected by a 15% increase in the LV ejection fraction (P = .029), a 45% increase in the LA ejection fraction (P < .001), and an 11% increase in the RV ejection fraction (P = NS). After treatment, the LV mass index and end-diastolic LV mass to volume ratio decreased by 17% (P < .001) and 10% (P = .002), respectively. None of the patients had late gadolinium myocardial enhancement. Conclusion: Cushing's syndrome is associated with subclinical biventricular and LA systolic dysfunctions that are reversible after treatment. Despite skeletal muscle atrophy, Cushing's syndrome patients have an increased LV mass, reversible upon correction of hypercortisolism. PMID:25093618

Identification of a feline leukemia virus variant that can use THTR1, FLVCR1, and FLVCR2 for infection.

PubMed

Shalev, Zvi; Duffy, Simon P; Adema, Karen W; Prasad, Rati; Hussain, Naveen; Willett, Brian J; Tailor, Chetankumar S

2009-07-01

The pathogenic subgroup C feline leukemia virus (FeLV-C) arises in infected cats as a result of mutations in the envelope (Env) of the subgroup A FeLV (FeLV-A). To better understand emergence of FeLV-C and potential FeLV intermediates that may arise, we characterized FeLV Env sequences from the primary FY981 FeLV isolate previously derived from an anemic cat. Here, we report the characterization of the novel FY981 FeLV Env that is highly related to FeLV-A Env but whose variable region A (VRA) receptor recognition sequence partially resembles the VRA sequence from the prototypical FeLV-C/Sarma Env. Pseudotype viruses bearing FY981 Env were capable of infecting feline, human, and guinea pig cells, suggestive of a subgroup C phenotype, but also infected porcine ST-IOWA cells that are normally resistant to FeLV-C and to FeLV-A. Analysis of the host receptor used by FY981 suggests that FY981 can use both the FeLV-C receptor FLVCR1 and the feline FeLV-A receptor THTR1 for infection. However, our results suggest that FY981 infection of ST-IOWA cells is not mediated by the porcine homologue of FLVCR1 and THTR1 but by an alternative receptor, which we have now identified as the FLVCR1-related protein FLVCR2. Together, our results suggest that FY981 FeLV uses FLVCR1, FLVCR2, and THTR1 as receptors. Our findings suggest the possibility that pathogenic FeLV-C arises in FeLV-infected cats through intermediates that are multitropic in their receptor use.

Comparison of standardized uptake values measured on F-NaF PET/CT scans using three different tube current intensities.

PubMed

Valadares, Agnes Araujo; Duarte, Paulo Schiavom; Woellner, Eduardo Bechtloff; Coura-Filho, George Barberio; Sapienza, Marcelo Tatit; Buchpiguel, Carlos Alberto

2015-01-01

To analyze standardized uptake values (SUVs) using three different tube current intensities for attenuation correction on (18)FNaF PET/CT scans. A total of 254 (18)F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs) drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH), right proximal femoral diaphysis (RF), and first lumbar vertebra (LV1) in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1). Mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. The three tube current values yielded similar results for SUV calculation.

New Doppler echocardiographic applications for the study of diastolic function

NASA Technical Reports Server (NTRS)

Garcia, M. J.; Thomas, J. D.; Klein, A. L.

1998-01-01

Doppler echocardiography is one of the most useful clinical tools for the assessment of left ventricular (LV) diastolic function. Doppler indices of LV filling and pulmonary venous (PV) flow are used not only for diagnostic purposes but also for establishing prognosis and evaluating the effect of therapeutic interventions. The utility of these indices is limited, however, by the confounding effects of different physiologic variables such as LV relaxation, compliance and filling pressure. Since alterations in these variables result in changes in Doppler indices of opposite direction, it is often difficult to determine the status of a given variable when a specific Doppler filling pattern is observed. Recently, color M-mode and tissue Doppler have provided useful insights in the study of diastolic function. These new Doppler applications have been shown to provide an accurate estimate of LV relaxation and appear to be relatively insensitive to the effects of preload compensation. This review will focus on the complementary role of color M-mode and tissue Doppler echocardiography and traditional Doppler indices of LV filling and PV flow in the assessment of diastolic function.

Aldosterone synthase inhibition improves cardiovascular function and structure in rats with heart failure: a comparison with spironolactone.

PubMed

Mulder, Paul; Mellin, Virginie; Favre, Julie; Vercauteren, Magali; Remy-Jouet, Isabelle; Monteil, Christelle; Richard, Vincent; Renet, Sylvanie; Henry, Jean Paul; Jeng, Arco Y; Webb, Randy L; Thuillez, Christian

2008-09-01

Inhibition of aldosterone synthase, the key enzyme in aldosterone formation, could be an alternative strategy for mineralocorticoid-receptor antagonists in congestive heart failure (CHF), but its effect in CHF is unknown. We compared, in rats with CHF, the effects of a 7 day and a 12 week treatment with the aldosterone synthase inhibitor FAD286 (4 mg kg(-1) day(-1)) with those induced by spironolactone (80 mg kg(-1) day(-1)). FAD286/spironolactone increased cardiac output without modifying arterial pressure. Long-term FAD286 and spironolactone reduced left ventricular (LV) end-diastolic pressure, LV relaxation constant, and LV dilatation, and these effects were more marked with FAD286, whereas both drugs reduced LV hypertrophy and collagen accumulation to the same extent. Long-term FAD286/spironolactone prevented CHF-related enhancement in LV ACE and reduction in LV ACE-2, but only FAD286 prevented the reduction in LV AT(2) receptors. FAD286, but not long-term spironolactone, reduced the CHF-related enhancements in LV reactive oxygen species, reduced-oxidized glutathione ratio, and aortic nicotinamide adenine dinucleotide phosphate oxidase activity. FAD286 normalized the CHF-induced impairment of endothelium-dependent vasodilatation. In experimental CHF, FAD286 and spironolactone improve LV haemodynamics, remodelling, and function, but only FAD286 persistently normalizes LV 'redox status'. These results suggest that aldosterone synthase inhibition is a potential therapeutic strategy for the treatment of CHF.

Effects of radiofrequency catheter ablation on left ventricular structure and function in patients with atrial fibrillation: a meta-analysis.

PubMed

Zhu, Pengju; Zhang, Yong; Jiang, Peiqing; Wang, Zhongsu; Wang, Jiangrong; Yin, Xiangcui; Hou, Yinglong

2014-08-01

Radiofrequency catheter ablation (RFCA) is an effective therapy for atrial fibrillation (AF). This study was designed to investigate the effects of RFCA on left ventricular (LV) structure and function in AF patients. A systematic literature search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials was performed to identify trials involving changes of LV structure and function in AF patients undergoing RFCA. Effect size was expressed as weighted mean difference (WMD) with 95% confidence interval (CI). LV end-diastolic diameter (LVEDD), LV end-systolic diameter (LVESD), LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LV ejection fraction (LVEF) were estimated. A total of 21 trials including 1,135 participants were qualified for this meta-analysis. Compared to the baseline values, there were significant decreases in LVEDV (WMD, -6.39 ml; 95%CI, -12.46 to -0.33) and LVESV (WMD, -6.39 ml; 95%CI, -11.35 to -1.42) and a significant improvement in LVEF (WMD, 6.23%; 95%CI, 3.70 to 8.75), but no significant changes were observed in LVEDD (WMD, -0.64 mm; 95%CI, -2.40 to 1.13) and LVESD (WMD, -0.38 mm; 95%CI, -1.32 to 0.56) after RFCA. Subgroup analysis demonstrated that patients with low LVEF (WMD, 11.90%; 95%CI, 9.16 to 14.64) gained more benefits than those with normal LVEF (WMD, 1.56%; 95%CI, 0.38 to 2.74). Besides, patients with chronic AF (WMD, 10.96%; 95%CI, 4.92 to 17.01) improved more than those with paroxysmal AF (WMD, 1.93%; 95%CI, -0.27 to 4.12). RFCA in AF patients could reverse LV structural remodeling and improve LV systolic function, especially in patients with low LVEF and chronic AF.

Heart-Derived Stem Cells in Miniature Swine with Coronary Microembolization: Novel Ischemic Cardiomyopathy Model to Assess the Efficacy of Cell-Based Therapy

PubMed Central

Young, Rebeccah F.; Leiker, Merced M.; Suzuki, Takayuki

2016-01-01

A major problem in translating stem cell therapeutics is the difficulty of producing stable, long-term severe left ventricular (LV) dysfunction in a large animal model. For that purpose, extensive infarction was created in sinclair miniswine by injecting microspheres (1.5 × 106 microspheres, 45 μm diameter) in LAD. At 2 months after embolization, animals (n = 11) were randomized to receive allogeneic cardiosphere-derived cells derived from atrium (CDCs: 20 × 106, n = 5) or saline (untreated, n = 6). Four weeks after therapy myocardial function, myocyte proliferation (Ki67), mitosis (phosphor-Histone H3; pHH3), apoptosis, infarct size (TTC), myocyte nuclear density, and cell size were evaluated. CDCs injected into infarcted and remodeled remote myocardium (global infusion) increased regional function and global function contrasting no change in untreated animals. CDCs reduced infarct volume and stimulated Ki67 and pHH3 positive myocytes in infarct and remote regions. As a result, myocyte number (nuclear density) increased and myocyte cell diameter decreased in both infarct and remote regions. Coronary microembolization produces stable long-term ischemic cardiomyopathy. Global infusion of CDCs stimulates myocyte regeneration and improves left ventricular ejection fraction. Thus, global infusion of CDCs could become a new therapy to reverse LV dysfunction in patients with asymptomatic heart failure. PMID:27738436

Clinical validation of the planar radionuclide ventriculography in patients with right ventricular dysfunction.

PubMed

Bontemps, L; Merabet, Y; Chevalier, P; Itti, R

2013-01-01

Gated radionuclide ventriculography (RNV) may be used for the evaluation of the right ventricular function. However, the accuracy of the method should be clinically validated in patients suffering from diseases with specific pathology of the right ventricle (RV) and with possible left ventricular (LV) interaction. Three groups of 15 patients each, diagnosed with arrhythmogenic right ventricular dysplasia (ARVD), pulmonary artery hypertension (PAH) or atrial septal defect (ASD) were compared to a group of normal subjects. The parameters for both ventricles were evaluated separately (ejection fractions: LVEF and RVEF, and intraventricular synchronism quantified as phase standard deviation: LVPSD and RVPSD) as well as the relation or interdependence of the right to left ventricle (RV/LV volume ratio, LV/RV ejection fraction and stroke volume ratios, and interventricular synchronism). All the variables as a whole were analyzed to identify groups of patients according to their functional behaviour. Significant differences were found between the patients and control group for the RV function while the LV function remained mostly within normal limits. When the RV function was considered, the control group and ASD patient group showed differences regarding the ARVD and PAH patients. On evaluating the RV/LV ratios, differences were found between the control group and the ASD group. In the PAH patients, LV function showed differences in relation to the rest of the groups. RNV is a reliable clinical tool to evaluate RV function in patients with RV abnormality. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

Relationship between left ventricular mechanics and low free triiodothyronine levels after myocardial infarction: a prospective study.

PubMed

Jankauskienė, Edita; Orda, Paulius; Barauskienė, Greta; Mickuvienė, Narseta; Brožaitienė, Julija; Vaškelytė, Jolanta Justina; Bunevičius, Robertas

2016-04-01

Low free triiodothyronine (fT3) levels following acute myocardial infarction (AMI) are associated with greater impairment in cardiac mechanics compared with patients with AMI who have normal values of thyroid hormones. The objectives are to investigate left ventricular (LV) function and mechanics during a 6-month follow-up after myocardial infarction and to evaluate their prognostic implication using two-dimensional (2D) echocardiography and 2D speckle-tracking echocardiography in patients with low fT3 levels. The study design is prospective cohort study. One hundred forty patients with first-onset AMI were grouped according to serum fT3 levels: low fT3 group (fT3 <3.2 pmol/L; n = 44) and control group (fT3 >3.2 pmol/L; n = 96). Low levels of fT3 were associated with greater LV diameters and LV end-diastolic volume, and decreased systolic LV function. Systolic apical and basal rotation, peak systolic global longitudinal strain and strain rate, and LV twist and torsion were significantly decreased in the low fT3 group. The prognostic implication for predicting low fT3 levels was evaluated using ROC analysis. LV end-diastolic diameter index is the most sensitive (94.12 %), but has low specificity (37.93 %; area = 0.659, p = 0.01). By contrast, LV end-systolic volume is the most specific (94.03 %), but has low sensitivity (26.32 %; area = 0.594, p = 0.04). Low fT3 levels are significantly associated with worse LV mechanics. Low fT3 levels are important for prediction of LV structure, function, rotation, and deformation parameters during the late post-myocardial infarction period.

Females have greater left ventricular twist mechanics than males during acute reductions to preload.

PubMed

Williams, Alexandra M; Shave, Rob E; Stembridge, Mike; Eves, Neil D

2016-07-01

Compared to males, females have smaller left ventricular (LV) dimensions and volumes, higher ejection fractions (EF), and higher LV longitudinal and circumferential strain. LV twist mechanics determine ventricular function and are preload-dependent. Therefore, the sex differences in LV structure and myocardial function may result in different mechanics when preload is altered. This study investigated sex differences in LV mechanics during acute challenges to preload. With the use of conventional and speckle-tracking echocardiography, LV structure and function were assessed in 20 males (24 ± 6.2 yr) and 20 females (23 ± 3.1 yr) at baseline and during progressive levels of lower body negative pressure (LBNP). Fourteen participants (8 males, 6 females) were also assessed following a rapid infusion of saline. LV end-diastolic volume, end-systolic volume, stroke volume (SV), and EF were reduced in both groups during LBNP (P < 0.001). While males had greater absolute volumes (P < 0.001), there were no sex differences in allometrically scaled volumes at any stage. Sex differences were not detected at baseline in basal rotation, apical rotation, or twist. Apical rotation and twist increased in both groups (P < 0.001) with LBNP. At -60 mmHg, females had greater apical rotation (P = 0.009), twist (P = 0.008), and torsion (P = 0.002) and faster untwisting velocity (P = 0.02) than males. There were no differences in mechanics following saline infusion. Females have larger LV twist and a faster untwisting velocity than males during large reductions to preload, supporting that females have a greater reliance on LV twist mechanics to maintain SV during severe reductions to preload. Copyright © 2016 the American Physiological Society.

Feline immunodeficiency virus and feline leukemia virus: frequency and associated factors in cats in northeastern Brazil.

PubMed

Lacerda, L C; Silva, A N; Freitas, J S; Cruz, R D S; Said, R A; Munhoz, A D

2017-05-10

Our aims were to determine the frequencies of feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) in owned and stray cats in the northeastern region of Brazil, ascertain the status of FeLV infection, and investigate potential associated factors among the owned cats. Blood samples from 200 asymptomatic owned cats and 30 stray cats were processed using nested PCR and commercial immunochromatographic tests to diagnose infections. To evaluate the factors associated with FIV and/or FeLV in owned cats, a semi-structured interview was conducted with each owner about the animal's environment, and these data were subjected to unconditional logistic regression. The frequencies for owned cats were 6% (12/200) and 3% (6/200) for FIV and FeLV, respectively. No owned cat was positive for both viruses. Stray cats showed frequencies of 6.66% (2/30) and 0% (0/30) for FIV and FeLV, respectively. Contact with other cats and living in peri-urban areas were considered to be risk factors (P < 0.05) for FIV. We did not identify any factors associated with infections with FeLV. Our results confirm the presence of these two retroviruses in the region under study. Our use of different diagnostic techniques allowed us to determine the frequency of retroviruses in the feline population more accurately, particularly with regard to infections by FeLV, which have complex pathogenesis.

Clinical characterization of 2D pressure field in human left ventricles

NASA Astrophysics Data System (ADS)

Borja, Maria; Rossini, Lorenzo; Martinez-Legazpi, Pablo; Benito, Yolanda; Alhama, Marta; Yotti, Raquel; Perez Del Villar, Candelas; Gonzalez-Mansilla, Ana; Barrio, Alicia; Fernandez-Aviles, Francisco; Bermejo, Javier; Khan, Andrew; Del Alamo, Juan Carlos

2014-11-01

The evaluation of left ventricle (LV) function in the clinical setting remains a challenge. Pressure gradient is a reliable and reproducible indicator of the LV function. We obtain 2D relative pressure field in the LV using in-vivo measurements obtained by processing Doppler-echocardiography images of healthy and dilated hearts. Exploiting mass conservation, we solve the Poisson pressure equation (PPE) dropping the time derivatives and viscous terms. The flow acceleration appears only in the boundary conditions, making our method weakly sensible to the time resolution of in-vivo acquisitions. To ensure continuity with respect to the discrete operator and grid used, a potential flow correction is applied beforehand, which gives another Poisson equation. The new incompressible velocity field ensures that the compatibility equation for the PPE is satisfied. Both Poisson equations are efficiently solved on a Cartesian grid using a multi-grid method and immersed boundary for the LV wall. The whole process is computationally inexpensive and could play a diagnostic role in the clinical assessment of LV function.

Geographic origin as a determinant of left ventricular mass and diastolic function - the Cardiovascular Risk in Young Finns Study.

PubMed

Vähämurto, L; Juonala, M; Ruohonen, S; Hutri-Kähönen, N; Kähönen, M; Laitinen, T; Tossavainen, P; Jokinen, E; Viikari, J; Raitakari, O T; Pahkala, K

2018-03-01

Eastern Finns have higher risk of coronary heart disease (CHD) and carotid intima-media thickness than western Finns although current differences in CHD risk factors are minimal. Left ventricular (LV) mass and diastolic function predict future cardiovascular events but their east-west differences are unknown. We examined the association of eastern/western baseline origin with LV mass and diastolic function. The study population included 2045 subjects of the Cardiovascular Risk in Young Finns Study with data from the baseline survey (1980) and the latest follow-up (2011) when echocardiography was performed at the age of 34-49 years. Subjects with eastern baseline origin had in 2011 higher LV mass (139±1.0 vs. 135±1.0 g, p=0.006) and E/e'-ratio indicating weaker LV diastolic function (4.86±0.03 vs. 4.74±0.03, p=0.02) than western subjects. Results were independent of age, sex, area of examination and CHD risk factors such as blood pressure and BMI (LV mass indexed with height: p<0.0001; E/e'-ratio: p=0.01). LV end-diastolic volume was higher among subjects with eastern baseline origin (135±0.9 vs. 131±0.9 ml, p=0.0011) but left atrial end-systolic volume, also indicating LV diastolic function, was not different between eastern and western subjects (43.4±0.5 vs. 44.0±0.5 ml, p=0.45). Most of the subjects were well within the normal limits of these echocardiographic measurements. In our healthy middle-aged population, geographic origin in eastern Finland associated with higher LV mass compared to western Finland. Higher E/e'-ratio suggests that subjects with eastern baseline origin might have higher prevalence of diastolic dysfunction in the future than western subjects.

Injectable Microsphere Gel Progressively Improves Global Ventricular Function, Regional Contractile Strain, and Mitral Regurgitation after Myocardial Infarction

PubMed Central

McGarvey, Jeremy R; Kondo, Norihiro; Witschey, Walter RT; Takebe, Manabu; Aoki, Chikashi; Burdick, Jason A.; Spinale, Francis G; Gorman, Joseph H; Pilla, James J; Gorman, Robert C

2014-01-01

Background There is continued need for therapies which reverse or abate the remodeling process following myocardial infarction (MI). In this study, we evaluate the longitudinal effects of calcium hydroxyapatite microsphere gel on regional strain, global ventricular function, and mitral regurgitation (MR) in a porcine MI model. Methods Twenty five Yorkshire swine were enrolled. Five were dedicated weight-matched controls. Twenty underwent posterolateral infarction by direct ligation of the circumflex artery and its branches. Infarcted animals were randomly divided into four groups: one week treatment, one week control, four week treatment, and four week control. Following infarction, animals received either twenty 150μl calcium hydroxyapatite gel or saline injections within the infarct. At their respective timepoints, echocardiograms, cardiac MRI, and tissue were collected for evaluation of MR, regional and global left ventricular function, wall thickness, and collagen content. Results Global and regional LV function were depressed in all infarcted subjects at one week compared to healthy controls. By four weeks post-infarction, global function had significantly improved in the calcium hydroxyapatite group compared to infarcted controls (EF 48.5±1.9% vs. 38.0±1.7%, p<0.01). Similarly, regional borderzone radial contractile strain (16.3±1.5% vs. 11.2±1.5%, p=0.04), MR grade (0.4±0.2 vs. 1.2±0.2, p=0.04), and infarct thickness (7.8±0.5mm vs. 4.5±0.2mm, p<0.01) were improved at this timepoint in the treatment group compared to infarct controls. Conclusions Calcium hydroxyapatite injection following MI progressively improves global LV function, borderzone function, and mitral regurgitation. Using novel biomaterials to augment infarct material properties is viable alternative in the current management of heart failure. PMID:25524397

Comparison of five-year outcomes of coronary artery bypass grafting versus percutaneous coronary intervention in patients with left ventricular ejection fractions≤50% versus >50% (from the CREDO-Kyoto PCI/CABG Registry Cohort-2).

PubMed

Marui, Akira; Kimura, Takeshi; Nishiwaki, Noboru; Mitsudo, Kazuaki; Komiya, Tatsuhiko; Hanyu, Michiya; Shiomi, Hiroki; Tanaka, Shiro; Sakata, Ryuzo

2014-10-01

Coronary heart disease is a major risk factor for left ventricular (LV) systolic dysfunction. However, limited data are available regarding long-term benefits of percutaneous coronary intervention (PCI) in the era of drug-eluting stent or coronary artery bypass grafting (CABG) in patients with LV systolic dysfunction with severe coronary artery disease. We identified 3,584 patients with 3-vessel and/or left main disease of 15,939 patients undergoing first myocardial revascularization enrolled in the CREDO-Kyoto PCI/CABG Registry Cohort-2. Of them, 2,676 patients had preserved LV systolic function, defined as an LV ejection fraction (LVEF) of >50% and 908 had impaired LV systolic function (LVEF≤50%). In patients with preserved LV function, 5-year outcomes were not different between PCI and CABG regarding propensity score-adjusted risk of all-cause and cardiac deaths. In contrast, in patients with impaired LV systolic function, the risks of all-cause and cardiac deaths after PCI were significantly greater than those after CABG (hazard ratio 1.49, 95% confidence interval 1.04 to 2.14, p=0.03 and hazard ratio 2.39, 95% confidence interval 1.43 to 3.98, p<0.01). In both patients with moderate (35%

Evaluation of left ventricular wall motion and function in patients with previous myocardial infarction by three-dimensional 99mTc-HSAD multigated cardiac pool imaging.

PubMed

Yamazaki, J; Naitou, K; Ishida, S; Uno, N; Saisho, K; Munakata, T; Morishita, T; Takano, M; Yabe, Y

1997-05-01

To evaluate left ventricular (LV) wall motion stereoscopically from all directions and to calculate the LV volume by three-dimensional (3D) imaging. 99mTc-DTPA human serum albumin-multigated cardiac pool-single photon emission computed tomography (99mTc-MUGA-SPECT) was performed. A new data processing program was developed with the Application Visualization System-Medical Viewer (AVS-MV) based on images obtained from 99mTc-MUGA-SPECT. In patients with previous myocardial infarction, LV function and LV wall motion were evaluated by 3D-99mTc-MUGA imaging. The LV end-diastolic volume (LVEDV) and end-systolic volume (LVESV) were obtained from 3D-99mTc-MUGA images by the surface rendering method, and the left ventricular ejection fraction (LVEF) was calculated at thresholds of 35% (T1), 40% (T2), 45% (T3), and 50% (T4). There was a strong correlation between the LV volume calculated by 3D-99mTc-MUGA imaging at a threshold of 40% and that determined by contrast left ventriculography (LVEDV: 194.7 +/- 36.0 ml vs. 198.7 +/- 39.1 ml, r = 0.791, p < 0.001; LVESV: 91.6 +/- 44.5 ml vs. 93.3 +/- 41.3 ml, r = 0.953, p < 0.001), respectively. When compared with the LVEF data obtained by left ventriculography, significant correlations were found for 3D images reconstructed at each threshold (T1: r = 0.966; T2: r = 0.962; T3: r = 0.958; and T4: r = 0.955). In addition, when LV wall motion obtained by 3D-99mTc-MUGA imaging (LAT and LAO views) was compared with the results obtained by left ventriculography (RAO and LAO views), there was good agreement. 3D-99mTc-MUGA imaging was superior in allowing evaluation of LV wall motion in all directions and in assessment of LV function, since data acquisition and image reconstruction could be done within a short time with the three-detector imaging system and AVS-MV. This method appears to be very useful for the observation of both LV wall motion and LV function in patients with ischemic heart disease, because it is a noninvasive examination.

Sildenafil ameliorates left ventricular T-tubule remodeling in a pressure overload-induced murine heart failure model

PubMed Central

Huang, Chun-kai; Chen, Bi-yi; Guo, Ang; Chen, Rong; Zhu, Yan-qi; Kutschke, William; Hong, Jiang; Song, Long-sheng

2016-01-01

Aim: Sildenafil, a phosphodiesterase 5 (PDE5) inhibitor, has been shown to exert beneficial effects in heart failure. The purpose of this study was to test whether sildenafil suppressed transverse-tubule (T-tubule) remodeling in left ventricular (LV) failure and thereby providing the therapeutic benefits. Methods: A pressure overload-induced murine heart failure model was established in mice by thoracic aortic banding (TAB). One day after TAB, the mice received sildenafil (100 mg·kg−1·d−1, sc) or saline for 5 weeks. At the end of treatment, echocardiography was used to examine LV function. Then the intact hearts were dissected out and placed in Langendorff-perfusion chamber for in situ confocal imaging of T-tubule ultrastructure from epicardial myocytes. Results: TAB surgery resulted in heart failure accompanied by remarkable T-tubule remodeling. Sildenafil treatment significantly attenuated TAB-induced cardiac hypertrophy and congestive heart failure, improved LV contractile function, and preserved T-tubule integrity in LV cardiomyocytes. But sildenafil treatment did not significantly affect the chamber dilation. The integrity of LV T-tubule structure was correlated with cardiac hypertrophy (R2=0.74, P<0.01) and global LV function (R2=0.47, P<0.01). Conclusion: Sildenafil effectively ameliorates LV T-tubule remodeling in TAB mice, revealing a novel mechanism underlying the therapeutic benefits of sildenafil in heart failure. PMID:26972492

High Spatial Resolution Multi-Organ Finite Element Modeling of Ventricular-Arterial Coupling

PubMed Central

Shavik, Sheikh Mohammad; Jiang, Zhenxiang; Baek, Seungik; Lee, Lik Chuan

2018-01-01

While it has long been recognized that bi-directional interaction between the heart and the vasculature plays a critical role in the proper functioning of the cardiovascular system, a comprehensive study of this interaction has largely been hampered by a lack of modeling framework capable of simultaneously accommodating high-resolution models of the heart and vasculature. Here, we address this issue and present a computational modeling framework that couples finite element (FE) models of the left ventricle (LV) and aorta to elucidate ventricular—arterial coupling in the systemic circulation. We show in a baseline simulation that the framework predictions of (1) LV pressure—volume loop, (2) aorta pressure—diameter relationship, (3) pressure—waveforms of the aorta, LV, and left atrium (LA) over the cardiac cycle are consistent with the physiological measurements found in healthy human. To develop insights of ventricular-arterial interactions, the framework was then used to simulate how alterations in the geometrical or, material parameter(s) of the aorta affect the LV and vice versa. We show that changing the geometry and microstructure of the aorta model in the framework led to changes in the functional behaviors of both LV and aorta that are consistent with experimental observations. On the other hand, changing contractility and passive stiffness of the LV model in the framework also produced changes in both the LV and aorta functional behaviors that are consistent with physiology principles. PMID:29551977

Left ventricular performance in various heart diseases with or without heart failure:--an appraisal by quantitative one-plane cineangiocardiography.

PubMed

Lien, W P; Lee, Y S; Chang, F Z; Chen, J J; Shieh, W B

1978-01-01

Quantitative one-plane cineangiocardiography in right anterior oblique position for evaluation of LV performance was carried out in 62 patients with various heart diseases and in 13 subjects with normal LV. Parameters for evaluating both pump and muscle performances were derived from volume and pressure measurements. Of 31 patients with either systolic hypertension or LV myocardial diseases (coronary artery disease or idiopathic cardiomyopathy), 14 had clinical evidence of LV failure before the study. It was found that mean VCF and EF were most sensitive indicators of impaired LV performance among the various parameters. There was a close correlation between mean VCF and EF, yet discordant changes of both parameters were noted in some patients. Furthermore, wall motion abnormalities were not infrequently observed in patients with coronary artery disease or primary cardiomyopathy. Therefore, assessment of at least three ejection properties (EF, mean VCF and wall motion abnormalities) are considered to be essential for full understanding of derangement of LV function in heart disease. This is especially true of patients with coronary artery disease. LV behavior in relation to different pathological stresses or lesions, such as chronic pressure or volume load, myocardial disease and mitral stenosis, was also studied and possible cause of impaired LV myocardial function in mitral stenosis was discussed.

Effects of Obesity on Cardiovascular Hemodynamics, Cardiac Morphology, and Ventricular Function.

PubMed

Alpert, Martin A; Omran, Jad; Bostick, Brian P

2016-12-01

Obesity produces a variety of hemodynamic alterations that may cause changes in cardiac morphology which predispose to left and right ventricular dysfunction. Various neurohormonal and metabolic alterations commonly associated with obesity may contribute to these abnormalities of cardiac structure and function. These changes in cardiovascular hemodynamics, cardiac morphology, and ventricular function may, in severely obese patients, predispose to heart failure, even in the absence of other forms of heart disease (obesity cardiomyopathy). In normotensive obese patients, cardiac involvement is commonly characterized by elevated cardiac output, low peripheral vascular resistance, and increased left ventricular (LV) end-diastolic pressure. Sleep-disordered breathing may lead to pulmonary arterial hypertension and, in association with left heart failure, may contribute to elevation of right heart pressures. These alterations, in association with various neurohormonal and metabolic abnormalities, may produce LV hypertrophy; impaired LV diastolic function; and less commonly, LV systolic dysfunction. Many of these alterations are reversible with substantial voluntary weight loss.

Blood Pressure and Left Ventricular Remodeling Among American Style Football Players

PubMed Central

Lin, Jeffrey; Wang, Francis; Weiner, Rory B.; DeLuca, James R.; Wasfy, Meagan M.; Berkstresser, Brant; Lewis, Gregory D.; Hutter, Adolph M.; Picard, Michael H.; Baggish, Aaron L.

2016-01-01

Objective To determine the relationships between American style football (ASF) participation, acquired left ventricular (LV) hypertrophy, and LV systolic function as assessed using contemporary echocardiographic parameters. Background Participation in ASF has been associated with the development of hypertension and LV hypertrophy. To what degree these processes impact LV function is unknown. Methods This is a prospective, longitudinal, cohort study evaluating NCAA Division I collegiate football athletes stratified by field position (linemen, n=30 vs. non-linemen, n=57) before and after a single competitive season with transthoracic echocardiography. LV systolic function was measured using complementary parameters of global longitudinal strain (GLS, 2D speckle-tracking) and ejection fraction (EF, 2D biplane). Results ASF participation was associated with field position-specific increases in systolic blood pressure (linemen Δ SBP = 10±8 mmHg vs. non-linemen Δ SBP = 3±7 mmHg, p<0.001) and an overall increase in incident LV hypertrophy (pre = 8% vs. post = 25%, p<0.05). Linemen who developed LV hypertrophy had concentric geometry (9/11, 82%) with decreased GLS (Δ = −1.1%, p<0.001) while non-linemen demonstrated eccentric LV hypertrophy (8/10, 80%) with increased GLS (Δ = +1.4%, p<0.001). In contrast, LV ejection fraction in the total cohort and when stratified by field position was not significantly affected by ASF participation. Among the total cohort, lineman field position, postseason weight, systolic blood pressure, average LV wall thickness, and relative wall thickness were all independent predictors of postseason GLS. Conclusions ASF participation at a lineman field position may lead to a form of sport-related myocardial remodeling that is pathologic rather than adaptive. Future study will be required to determine if targeted efforts to control blood pressure, minimize weight gain, and to include an element of aerobic conditioning in this subset of athletes may attenuate this process and translate into tangible downstream health benefits. PMID:27931524

Determination of left ventricular volume, ejection fraction, and myocardial mass by real-time three-dimensional echocardiography

NASA Technical Reports Server (NTRS)

Qin, J. X.; Shiota, T.; Thomas, J. D.

2000-01-01

Reconstructed three-dimensional (3-D) echocardiography is an accurate and reproducible method of assessing left ventricular (LV) functions. However, it has limitations for clinical study due to the requirement of complex computer and echocardiographic analysis systems, electrocardiographic/respiratory gating, and prolonged imaging times. Real-time 3-D echocardiography has a major advantage of conveniently visualizing the entire cardiac anatomy in three dimensions and of potentially accurately quantifying LV volumes, ejection fractions, and myocardial mass in patients even in the presence of an LV aneurysm. Although the image quality of the current real-time 3-D echocardiographic methods is not optimal, its widespread clinical application is possible because of the convenient and fast image acquisition. We review real-time 3-D echocardiographic image acquisition and quantitative analysis for the evaluation of LV function and LV mass.

Determination of left ventricular volume, ejection fraction, and myocardial mass by real-time three-dimensional echocardiography.

PubMed

Qin, J X; Shiota, T; Thomas, J D

2000-11-01

Reconstructed three-dimensional (3-D) echocardiography is an accurate and reproducible method of assessing left ventricular (LV) functions. However, it has limitations for clinical study due to the requirement of complex computer and echocardiographic analysis systems, electrocardiographic/respiratory gating, and prolonged imaging times. Real-time 3-D echocardiography has a major advantage of conveniently visualizing the entire cardiac anatomy in three dimensions and of potentially accurately quantifying LV volumes, ejection fractions, and myocardial mass in patients even in the presence of an LV aneurysm. Although the image quality of the current real-time 3-D echocardiographic methods is not optimal, its widespread clinical application is possible because of the convenient and fast image acquisition. We review real-time 3-D echocardiographic image acquisition and quantitative analysis for the evaluation of LV function and LV mass.

Coordinated disintegration reactions mediated by Moloney murine leukemia virus integrase.

PubMed Central

Donzella, G A; Jonsson, C B; Roth, M J

1996-01-01

The protein-DNA and protein-protein interactions important for function of the integrase (IN) protein of Moloney murine leukemia virus (M-MuLV) were investigated by using a coordinated-disintegration assay. A panel of M-MuLV IN mutants and substrate alterations highlighted distinctions between the intermolecular and intramolecular reactions of coordinated disintegration. Mispairing of the crossbone single-strand region and altered long terminal repeat (LTR) positioning affected the intermolecular, but not the intramolecular, reactions of coordinated disintegration. Partial components of the crossbone substrate were coordinated by M-MuLV IN, indicating a reliance on both LTR and target DNA determinants for substrate assembly. The intramolecular reaction was dependent on the presence of either the HHCC domain or a crossbone LTR 5' single-stranded tail. An M-MuLV IN mutant without the HHCC domain (Ndelta105) catalyzed reduced levels of double disintegration but not single disintegration. A separately purified HHCC domain protein (Cdelta232) stimulated double disintegration mediated by Ndelta105, suggesting a role of the N-terminal HHCC domain in stable IN-IN and IN-DNA interactions. Significantly, crossbone substrates lacking the LTR 5' tails were not recognized by the fingerless Ndelta105 protein. Collectively, these data suggest similar roles of the HHCC domain and 5' LTR tail in substrate recognition and modulation of IN activity. PMID:8648728

Matrix metalloproteinases and left ventricular function and structure in spinal cord injured subjects.

PubMed

Schreiber, Roberto; Paim, Layde R; de Rossi, Guilherme; Matos-Souza, José R; Costa E Silva, Anselmo de A; Souza, Cristiane M; Borges, Mariane; Azevedo, Eliza R; Alonso, Karina C; Gorla, José I; Cliquet, Alberto; Nadruz, Wilson

2014-11-01

Subjects with spinal cord injury (SCI) exhibit impaired left ventricular (LV) diastolic function, which has been reported to be attenuated by regular physical activity. This study investigated the relationship between circulating matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) and echocardiographic parameters in SCI subjects and the role of physical activity in this regard. Forty-two men with SCI [19 sedentary (S-SCI) and 23 physically-active (PA-SCI)] were evaluated by clinical, anthropometric, laboratory, and echocardiographic analysis. Plasmatic pro-MMP-2, MMP-2, MMP-8, pro-MMP-9, MMP-9, TIMP-1 and TIMP-2 levels were determined by enzyme-linked immunosorbent assay and zymography. PA-SCI subjects presented lower pro-MMP-2 and pro-MMP-2/TIMP-2 levels and improved markers of LV diastolic function (lower E/Em and higher Em and E/A values) than S-SCI ones. Bivariate analysis showed that pro-MMP-2 correlated inversely with Em and directly with E/Em, while MMP-9 correlated directly with LV mass index and LV end-diastolic diameter in the whole sample. Following multiple regression analysis, pro-MMP-2, but not physical activity, remained associated with Em, while MMP-9 was associated with LV mass index in the whole sample. These findings suggest differing roles for MMPs in LV structure and function regulation and an interaction among pro-MMP-2, diastolic function and physical activity in SCI subjects. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of 4 classes of cardiovascular drugs on ventricular function in dogs with mitral regurgitation.

PubMed

Nakayama, Tomohiro; Nishijima, Yoshinori; Miyamoto, Mutsumi; Hamlin, Robert L

2007-01-01

There have been few trials in which dogs with mitral regurgitation (MR) have been treated with various cardioactive drugs to determine effects on left ventricular (LV) function. Four classes of cardiovascular drugs may improve LV function in dogs with MR without increasing MR. Nine mature dogs were included in the study. MR was produced in 9 dogs. Five months later under butorphanol narcosis, parameters of LV function and left atrial dimension (LAD) were monitored by LV micromanometry and echocardiography/Doppler. Dogs were given (in random order) enalaprilat, nitroglycerine, ouabain, milrinone, and placebo. Nitroglycerin produced no significant change; milrinone and ouabain increased contractility; ouabain decreased heart rate; and there was evidence that enalaprilat and milrinone decreased LAD. Milrinone and ouabain decreased isovolumetric contraction time and therefore the time available for MR. There was no evidence that a positive inotrope increased MR despite increasing LV contractility and stroke volume. This study contradicts the hypotheses that (1) strengthening the left ventricle may increase MR and (2) treatment of MR (even before symptoms of heart failure develop) may decrease LAD. It is reasonable that strengthening the force of LV contraction should increase the driving pressure for MR; however, this effect did not appear to increase MR. Although some investigators believe that treating dogs with MR with afterload reducers and decreasing hindrance to ejection of blood from the LV to aorta may lengthen life by decreasing MR, there did not appear to be a reduction in MR, at least in response to the angiotensin-converting enzyme (ACE) inhibitor.

Association between left atrial phasic conduit function and early atrial fibrillation recurrence in patients undergoing electrical cardioversion.

PubMed

Degiovanni, Anna; Boggio, Enrico; Prenna, Eleonora; Sartori, Chiara; De Vecchi, Federica; Marino, Paolo N

2018-04-01

Diastolic dysfunction promotes atrial fibrillation (AF) inducing left atrial (LA) remodeling, with chamber dilation and fibrosis. Predominance of LA phasic conduit (LAC) function should reflect not only chamber alterations but also underlying left ventricular (LV) filling impairment. Thus, LAC was tested as possible predictor of early AF relapse after electrical cardioversion (EC). 96 consecutive patients, who underwent EC for persistent non-valvular AF, were prospectively enrolled. Immediately after successful EC (3 h ± 15 min), an echocardiographic apical four-chamber view was acquired with transmitral velocities, annular tissue Doppler and simultaneous LV and LA three-dimensional full-volume datasets. Then, from LA-LV volumetric curves we computed LAC as: [(LV maximum - LV minimum) - (LA maximum - LA minimum) volume], expressed as % LV stroke volume. LA pump, immediately post-EC, was assumed and verified as being negligible. Sinus rhythm persistence at 1 month was checked with ECG-Holter monitoring. At 1 month 62 patients were in sinus rhythm and 34 in AF. AF patients presented pre-EC higher E/é values (p = 0.012), no major LA volume differences (p = NS), but a stiffer LV cavity (p = 0.012) for a comparable LV capacitance (p = 0.461). Conduit contributed more (p < 0.001) to LV stroke volume in AF subpopulation. Multiple regression revealed LAC as the most significant AF predictor (p = 0.013), even after correction for biometric characteristics and pharmacotherapy (p = 0.008). Our data suggest that LAC larger contribution to LV filling soon after EC reflects LA-LV stiffening, which skews atrioventricular interaction leading to AF perpetuation and makes conduit dominance a powerful predictor of early AF recurrence.

U3 long terminal repeat-mediated induction of intracellular immunity by a murine retrovirus: a novel model of latency for retroviruses.

PubMed Central

Gorska-Flipot, I; Huang, M; Cantin, M; Rassart, E; Massé, G; Jolicoeur, P

1992-01-01

BL/VL3 radiation leukemia virus (RadLV) is a thymotropic, highly leukemogenic murine leukemia virus (MuLV) which is unable to replicate in vitro in mouse fibroblasts. We have previously reported that the U3 long terminal repeat region of its genome is responsible for this block (E. Rassart, Y. Paquette, and P. Jolicoeur, J. Virol. 62:3840-3848, 1988). By using hybrids of permissive and resistant cells infected with BL/VL3 RadLV or fibrotropic MuLV, we found that the resistant phenotype was dominant. Investigation to determine at which step of the virus cycle the block operates revealed that integration, transcription, and translation of the BL/VL3 viral genome occurred at normal levels in nonpermissive cells. The BL/VL3 RadLV Pr65gag proteins made in nonpermissive cells were also myristylated and located at the membrane, and the levels of their cleaved products were similar to those of fibrotropic MuLV. However, processing of BL/VL3 RadLV Pr85env was impaired in nonpermissive cells. Virions were not released into the culture medium of nonpermissive cells, as measured by reverse transcriptase activity and by content in p30 or gp70 protein and as documented by lower levels of budding particles seen by electron microscopy. These results indicate that BL/VL3 RadLV replication is blocked at a late stage of the virus cycle, i.e., at virion assembly. Interestingly, these BL/VL3 RadLV-infected nonpermissive fibroblasts were resistant to superinfection by fibrotropic Moloney MuLV, and this resistance also occurred at a late step of the Moloney virus cycle. Since this block is dominant, it appears that the U3 long terminal repeat region of the BL/VL3 viral genome has the ability to induce a cellular suppressor factor(s), thus bringing intracellular immunity against itself and against other ecotropic MuLVs. Images PMID:1433513

Left ventricular myocardial velocities and deformation indexes in top-level athletes.

PubMed

D'Andrea, Antonello; Cocchia, Rosangela; Riegler, Lucia; Scarafile, Raffaella; Salerno, Gemma; Gravino, Rita; Golia, Enrica; Pezzullo, Enrica; Citro, Rodolfo; Limongelli, Giuseppe; Pacileo, Giuseppe; Cuomo, Sergio; Caso, Pio; Russo, Maria Giovanna; Bossone, Eduardo; Calabrò, Raffaele

2010-12-01

The aim of this study was to define the range of left ventricular (LV) velocities and deformation indexes in highly trained athletes, analyzing potential differences induced by different long-term training protocols. Standard echocardiography, pulsed-wave tissue Doppler echocardiography, and two-dimensional strain echocardiography of the interventricular septum and lateral wall were performed in 370 endurance athletes and 280 power athletes. Using pulsed-wave tissue Doppler, the following parameters of myocardial function were assessed: systolic peak velocities (S(m)), early (E(m)) and late (A(m)) diastolic velocities, and the E(m)/A(m) ratio. By two-dimensional strain echocardiography, peaks of regional systolic strain and LV global longitudinal strain were calculated. LV mass index and ejection fraction did not significantly differ between the two groups. However, power athletes showed an increased sum of wall thicknesses (P < .01) and relative wall thickness, while LV stroke volume and LV end-diastolic diameter (P < .001) were greater in endurance athletes. By pulsed-wave tissue Doppler analysis, E(m) and E(m)/A(m) at both the septal and lateral wall levels were higher in endurance athletes. By two-dimensional strain echocardiography, myocardial deformation indexes were comparable between the two groups. E(m)/A(m) ratios ≥ 1 were found in the overall population, while 90 % of athletes had an E(m) ≥ 16 cm/sec, S(m) ≥ 10 cm/sec, and global longitudinal strain ≤ -16%. Multivariate analyses evidenced independent positive association between Em peak velocity and LV end-diastolic volume (P < .001) and an independent correlation of global longitudinal strain with the sum of LV wall thicknesses (P < .005). This study describes the full spectrum of systolic and diastolic myocardial velocities and deformation indexes in a large population of competitive athletes. Copyright © 2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

Deep learning analysis of the myocardium in coronary CT angiography for identification of patients with functionally significant coronary artery stenosis.

PubMed

Zreik, Majd; Lessmann, Nikolas; van Hamersvelt, Robbert W; Wolterink, Jelmer M; Voskuil, Michiel; Viergever, Max A; Leiner, Tim; Išgum, Ivana

2018-02-01

In patients with coronary artery stenoses of intermediate severity, the functional significance needs to be determined. Fractional flow reserve (FFR) measurement, performed during invasive coronary angiography (ICA), is most often used in clinical practice. To reduce the number of ICA procedures, we present a method for automatic identification of patients with functionally significant coronary artery stenoses, employing deep learning analysis of the left ventricle (LV) myocardium in rest coronary CT angiography (CCTA). The study includes consecutively acquired CCTA scans of 166 patients who underwent invasive FFR measurements. To identify patients with a functionally significant coronary artery stenosis, analysis is performed in several stages. First, the LV myocardium is segmented using a multiscale convolutional neural network (CNN). To characterize the segmented LV myocardium, it is subsequently encoded using unsupervised convolutional autoencoder (CAE). As ischemic changes are expected to appear locally, the LV myocardium is divided into a number of spatially connected clusters, and statistics of the encodings are computed as features. Thereafter, patients are classified according to the presence of functionally significant stenosis using an SVM classifier based on the extracted features. Quantitative evaluation of LV myocardium segmentation in 20 images resulted in an average Dice coefficient of 0.91 and an average mean absolute distance between the segmented and reference LV boundaries of 0.7 mm. Twenty CCTA images were used to train the LV myocardium encoder. Classification of patients was evaluated in the remaining 126 CCTA scans in 50 10-fold cross-validation experiments and resulted in an area under the receiver operating characteristic curve of 0.74 ± 0.02. At sensitivity levels 0.60, 0.70 and 0.80, the corresponding specificity was 0.77, 0.71 and 0.59, respectively. The results demonstrate that automatic analysis of the LV myocardium in a single CCTA scan acquired at rest, without assessment of the anatomy of the coronary arteries, can be used to identify patients with functionally significant coronary artery stenosis. This might reduce the number of patients undergoing unnecessary invasive FFR measurements. Copyright © 2017 Elsevier B.V. All rights reserved.

Relationship between improvement in left ventricular dyssynchrony and contractile function and clinical outcome with cardiac resynchronization therapy: the MADIT-CRT trial.

PubMed

Pouleur, Anne-Catherine; Knappe, Dorit; Shah, Amil M; Uno, Hajime; Bourgoun, Mikhail; Foster, Elyse; McNitt, Scott; Hall, W Jackson; Zareba, Wojciech; Goldenberg, Ilan; Moss, Arthur J; Pfeffer, Marc A; Solomon, Scott D

2011-07-01

To assess long-term effects of cardiac resynchronization therapy (CRT) on left ventricular (LV) dyssynchrony and contractile function, by two-dimensional speckle-tracking echocardiography, compared with implantable cardioverter defibrillator (ICD) only in MADIT-CRT. We studied 761 patients in New York Heart Association I/II, ejection fraction ≤30%, and QRS ≥130 ms [n = 434, CRT-defibrillator (CRT-D), n = 327, ICD] with echocardiographic studies available at baseline and 12 months. Dyssynchrony was determined as the standard deviation of time to peak transverse strain between 12 segments of apical four- and two-chamber views, and contractile function as global longitudinal strain (GLS) by averaging longitudinal strain over these 12 segments. We compared changes in LV dyssynchrony and contractile function between treatment groups and assessed relationships between these changes over the first year and subsequent outcomes (median post 1-year follow-up = 14.9 months). Mean changes in LV dyssynchrony and contractile function measured by GLS in the overall population were, respectively, -29 ± 83 ms and -1 ± 2.9%. However, both LV dyssynchrony (CRT-D: -47 ± 83 ms vs. ICD: -6 ± 76 ms, P < 0.001) and contractile function (CRT-D: -1.4 ± 3.1% vs. ICD: -0.4 ± 2.5%, P < 0.001) improved to a greater extent in the CRT-D group compared with the ICD-only group. A greater improvement in dyssynchrony and contractile function at 1 year was associated with lower rates of the subsequent primary outcome of death or heart failure, adjusting for baseline dyssynchrony and contractile function, treatment arm, ischaemic status, and change in LV end-systolic volume. Each 20 ms decrease in LV dyssynchrony was associated with a 7% reduction in the primary outcome (P = 0.047); each 1% improvement in GLS over the 12-month period was associated with a 24% reduction in the primary outcome (P < 0.001). Cardiac resynchronization therapy resulted in a significant improvement in both LV dyssynchrony and contractile function measured by GLS compared with ICD only and these improvements were associated with better subsequent outcomes.

Evaluation of mechanical dyssynchrony and myocardial perfusion using phase analysis of gated SPECT imaging in patients with left ventricular dysfunction

PubMed Central

Trimble, Mark A.; Borges-Neto, Salvador; Honeycutt, Emily F.; Shaw, Linda K.; Pagnanelli, Robert; Chen, Ji; Iskandrian, Ami E.; Garcia, Ernest V.; Velazquez, Eric J.

2010-01-01

Background Using phase analysis of gated single photon emission computed tomography (SPECT) imaging, we examined the relation between myocardial perfusion, degree of electrical dyssynchrony, and degree of SPECT-derived mechanical dyssynchrony in patients with left ventricular (LV) dysfunction. Methods and Results We retrospectively examined 125 patients with LV dysfunction and ejection fraction of 35% or lower. Fourier analysis converts regional myocardial counts into a continuous thickening function, allowing resolution of phase of onset of myocardial thickening. The SD of LV phase distribution (phase SD) and histogram bandwidth describe LV phase dispersion as a measure of dyssynchrony. Heart failure (HF) patients with perfusion abnormalities ities have higher degrees of dyssynchrony measured by median phase SD (45.5° vs 27.7°, P < .0001) and bandwidth (117.0° vs 73.0°, P = .0006). HF patients with prolonged QRS durations have higher degrees of dyssynchrony measured by median phase SD (54.1° vs 34.7°, P < .0001) and bandwidth (136.5° vs 99.0°, P = .0005). Mild to moderate correlations exist between QRS duration and phase analysis indices of phase SD (r = 0.50) and bandwidth (r = 0.40). Mechanical dyssynchrony (phase SD >43°) was 43.2%. Conclusions HF patients with perfusion abnormalities or prolonged QRS durations QRS durations have higher degrees of mechanical dyssynchrony. Gated SPECT myocardial perfusion imaging can quantify myocardial function, perfusion, and dyssynchrony and may help in evaluating patients for cardiac resynchronization therapy. PMID:18761269

Dependence of Cardiac Systolic Function on Elevated Fatty Acid Availability in Obese, Insulin-Resistant Rats.

PubMed

Smith, Wayne; Norton, Gavin R; Woodiwiss, Angela J; Lochner, Amanda; du Toit, Eugene F

2016-07-01

Clinical data advocating an adverse effect of obesity on left ventricular (LV) systolic function independent of comorbidities is controversial. We hypothesized that in obesity with prediabetic insulin resistance, circulating fatty acids (FAs) become a valuable fuel source in the maintenance of normal systolic function. Male Wistar rats were fed a high caloric diet for 32 weeks to induce obesity. Myocardial LV systolic function was assessed using echocardiography and isolated heart preparations. Aortic output was reduced in obese rat hearts over a range of filling pressures (for example: 15 cmH2O, obese: 32.6 ± 1.2 ml/min vs control: 46.2 ± 0.9 ml/min, P < .05) when perfused with glucose alone. Similarly, the slope of the LV end-systolic pressure-volume relationship decreased, and there was a right shift in the LV end-systolic stress-strain relationship as determined in Langendorff perfused, isovolumic rat heart preparations in the presence of isoproterenol (10(-8)M) (LV systolic stress-strain relationship and a reduced load-independent intrinsic systolic myocardial function, obese: 791 ± 62 g/cm(2) vs control: 1186 ± 74 g/cm(2), P < .01). The addition of insulin to the perfusion buffer improved aortic output, whereas the addition of FAs completely normalized aortic output. LV function was maintained in obese animals in vivo during an inotropic challenge. Elevated circulating FA levels may be important to maintain myocardial systolic function in the initial stages of obesity and insulin resistance. Copyright © 2016 Elsevier Inc. All rights reserved.

Changes in Speckle Tracking Echocardiography Measures of Ventricular Function after Percutaneous Implantation of the Edwards SAPIEN Transcatheter Heart Valve in the Pulmonary Position

PubMed Central

Chowdhury, Shahryar M.; Hijazi, Ziyad M.; Rhodes, John F.; Kar, Saibal; Makkar, Raj; Mullen, Michael; Cao, Qi-Ling; Mandinov, Lazar; Buckley, Jason; Pietris, Nicholas P.; Shirali, Girish S.

2015-01-01

Background Patients with free pulmonary regurgitation or mixed pulmonary stenosis and regurgitation and severely dilated right ventricles (RV) show little improvement in ventricular function after pulmonary valve replacement when assessed by traditional echocardiographic markers. We evaluated changes in right and left ventricular (LV) function using speckle tracking echocardiography in patients after SAPIEN transcatheter pulmonary valve (TPV) placement. Methods Echocardiograms were evaluated at baseline, discharge, 1 and 6 months after TPV placement in 24 patients from 4 centers. Speckle tracking measures of function included peak longitudinal strain, strain rate, and early diastolic strain rate. RV fractional area change, tricuspid annular plane systolic excursion, and left ventricular LV ejection fraction were assessed. Routine Doppler and tissue Doppler velocities were measured. Results At baseline, all patients demonstrated moderate to severe pulmonary regurgitation; this improved following TPV placement. No significant changes were detected in conventional measures of RV or LV function at 6 months. RV longitudinal strain (−16.9% vs. −19.6%, P < 0.01), strain rate (−0.87 s−1 vs. −1.16 s−1, P = 0.01), and LV longitudinal strain (−16.2% vs. −18.2%, P = 0.01) improved between baseline and 6 month follow-up. RV early diastolic strain rate, LV longitudinal strain rate and early diastolic strain rate showed no change. Conclusion Improvements in RV longitudinal strain, strain rate, and LV longitudinal strain are seen at 6 months post-TPV. Diastolic function does not appear to change at 6 months. Speckle tracking echocardiography may be more sensitive than traditional measures in detecting changes in systolic function after TPV implantation. (Echocardiography 2015;32:461–469) PMID:25047063

Impact of aerobic interval training and continuous training on left ventricular geometry and function: a SAINTEX-CAD substudy.

PubMed

Van De Heyning, Caroline M; De Maeyer, Catherine; Pattyn, Nele; Beckers, Paul J; Cornelissen, Véronique A; Goetschalckx, Kaatje; Possemiers, Nadine; Van Craenenbroeck, Emeline M; Voigt, Jens-Uwe; Vanhees, Luc; Shivalkar, Bharati

2018-04-15

Increase of exercise capacity (peak VO 2 ) after cardiac rehabilitation improves outcome in patients with coronary artery disease (CAD). Systolic and diastolic function have been associated with peak VO 2 , but their role towards improvement of exercise capacity remains unclear. It is unknown which exercise intensity has the most beneficial impact on left ventricular (LV) geometry and function in CAD patients without heart failure. 200 stable CAD patients without heart failure were randomized to 3months of aerobic interval training (AIT) or aerobic continuous training (ACT). Cardiopulmonary exercise test and transthoracic echocardiography were scheduled before and after 3months of training. At baseline, a higher peak VO 2 correlated with lower LV posterior wall thickness (p=0.002), higher LV ejection fraction (p=0.008), better LV global longitudinal strain (p=0.043) and lower E/e' (0=0.001). After multivariate stepwise regression analysis only E/é remained an independent predictor of peak VO 2 (p=0.042). Improvement of peak VO 2 after 3months of training correlated with reverse remodeling of the interventricular septum (p=0.005), enlargement of LV diastolic volume (p=0.007) and increase of LV stroke volume (p=0.018) but not with other indices of systolic or diastolic function. Significant reduction of the interventricular septum thickness after cardiac rehabilitation was observed (p=0.012), with a trend towards more reverse remodeling after ACT compared to AIT (p=0.054). In contrast, there were no changes in other parameters of LV geometry, diastolic or systolic function. Systolic and diastolic function are determinants of baseline exercise capacity in CAD patients without heart failure, but do not seem to mediate improvement of peak VO 2 after either AIT or ACT. Copyright © 2017 Elsevier B.V. All rights reserved.

Nuclear factors that bind to the enhancer region of nondefective Friend murine leukemia virus.

PubMed Central

Manley, N R; O'Connell, M A; Sharp, P A; Hopkins, N

1989-01-01

Nondefective Friend murine leukemia virus (MuLV) causes erythroleukemia when injected into newborn NFS mice, while Moloney MuLV causes T-cell lymphoma. Exchange of the Friend virus enhancer region, a sequence of about 180 nucleotides including the direct repeat and a short 3'-adjacent segment, for the corresponding region in Moloney MuLV confers the ability to cause erythroid disease on Moloney MuLV. We have used the electrophoretic mobility shift assay and methylation interference analysis to identify cellular factors which bind to the Friend virus enhancer region and compared these with factors, previously identified, that bind to the Moloney virus direct repeat (N. A. Speck and D. Baltimore, Mol. Cell. Biol. 7:1101-1110, 1987). We identified five binding sites for sequence-specific DNA-binding proteins in the Friend virus enhancer region. While some binding sites are present in both the Moloney and Friend virus enhancers, both viruses contain unique sites not present in the other. Although none of the factors identified in this report which bind to these unique sites are present exclusively in T cells or erythroid cells, they bind to three regions of the enhancer shown by genetic analysis to encode disease specificity and thus are candidates to mediate the tissue-specific expression and distinct disease specificities encoded by these virus enhancer elements. Images PMID:2778872

Intraventricular flow alterations due to dyssynchronous wall motion

NASA Astrophysics Data System (ADS)

Pope, Audrey M.; Lai, Hong Kuan; Samaee, Milad; Santhanakrishnan, Arvind

2015-11-01

Roughly 30% of patients with systolic heart failure suffer from left ventricular dyssynchrony (LVD), in which mechanical discoordination of the ventricle walls leads to poor hemodynamics and suboptimal cardiac function. There is currently no clear mechanistic understanding of how abnormalities in septal-lateral (SL) wall motion affects left ventricle (LV) function, which is needed to improve the treatment of LVD using cardiac resynchronization therapy. We use an experimental flow phantom with an LV physical model to study mechanistic effects of SL wall motion delay on LV function. To simulate mechanical LVD, two rigid shafts were coupled to two segments (apical and mid sections) along the septal wall of the LV model. Flow through the LV model was driven using a piston pump, and stepper motors coupled to the above shafts were used to locally perturb the septal wall segments relative to the pump motion. 2D PIV was used to examine the intraventricular flow through the LV physical model. Alterations to SL delay results in a reduction in the kinetic energy (KE) of the flow field compared to synchronous SL motion. The effect of varying SL motion delay from 0% (synchronous) to 100% (out-of-phase) on KE and viscous dissipation will be presented. This research was supported by the Oklahoma Center for Advancement of Science and Technology (HR14-022).

The relationship between arterial wall stiffness and left ventricular dysfunction.

PubMed

Hu, Y; Li, L; Shen, L; Gao, H

2013-05-01

The purpose of this study was to explore the relationship between left ventricular (LV) dysfunction and arterial wall stiffening. A total of 218 patients over the age of 45 diagnosed with hypertension in Jinan City and hospitalised between 2010 and 2011 were included in this study. LV function was evaluated using echocardiography (ECHO). Blood pressure was monitored with an automated tonometric device, and the parameters of arterial wall stiffness were measured. In addition, the metabolic parameters of blood samples, such as glucose and lipids, were also determined using the Cobas E601 analyser. Stiffness parameter beta positively correlated with LV diastolic function (E/Em ratio) (r = 0.255, p < 0.001). LV end-diastolic diameter not only related to the E/Em ratio (r = 0.196, p = 0.009) but also with beta (r = 0.220, p = 0.002). The stiffness parameter beta was an early indicator of E/Em ratio as determined by multiple regression analysis (R (2) = 0.381, p < 0.01). Age, blood pressure and fasting blood glucose contributed to stiffness parameter beta (p < 0.05), as well as the E/Em ratio (p < 0.01). Our findings suggested that LV dysfunction may have a direct relationship to arterial stiffening, independently of having similar risk factors. In addition, arterial stiffness can be an independent predictor of LV diastolic function, suggesting that the severity of arterial stiffness directly correlates with the severity of LV dysfunction.

Echocardiographic evaluation of myocardial changes observed after closure of patent ductus arteriosus in dogs.

PubMed

Hamabe, L; Kim, S; Yoshiyuki, R; Fukayama, T; Nakata, T M; Fukushima, R; Tanaka, R

2015-01-01

Closure of PDA can be associated with echocardiographic changes including deterioration of LV systolic function. Although PDA is commonly encountered in dogs, few comprehensive reports of echocardiographic changes in dogs with PDA closure are available. To evaluate the short-term echocardiographic changes observed after PDA closure in dogs using strain analysis. Seventeen client-owned dogs with left-to-right PDA. Echocardiographic evaluations, including standard echocardiography and two-dimensional tissue tracking (2DTT), were performed before and within 3 days of PDA closure. Preclosure examination showed LV and left atrial dilatation indicating volume overload as a result of PDA. Closure of PDA resulted in significant reduction of LVIDd (<.0001) and LA/Ao (0.01) without change in LVIDs, suggestive of decreased preload. Postclosure LV systolic dysfunction was observed with significant decreased in FS (<.0001) and strain values (P = .0039 for radial strains, P = .0005 for circumferential strains). Additionally, significant LV dyssynchrony (P = .0162) was observed after closure of PDA. Closure of PDA resulted in decreased preload as a result of alleviation of LV volume overload, which in turn caused transient deterioration of LV systolic function. Additionally, this study demonstrated that strain analysis is load dependent. Therefore, care should be taken when interpreting strain measurements as an indicator of LV systolic function. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.

Real-time three-dimensional echocardiographic study of left ventricular function after infarct exclusion surgery for ischemic cardiomyopathy

NASA Technical Reports Server (NTRS)

Qin, J. X.; Shiota, T.; McCarthy, P. M.; Firstenberg, M. S.; Greenberg, N. L.; Tsujino, H.; Bauer, F.; Travaglini, A.; Hoercher, K. J.; Buda, T.;

Effect of streptozotocin-induced diabetes on left ventricular function in adult rats: an in vivo Pinhole Gated SPECT study

PubMed Central

Cosyns, Bernard; Droogmans, Steven; Weytjens, Caroline; Lahoutte, Tony; Van Camp, Guy; Schoors, Danny; Franken, Philippe R

2007-01-01

Background Recent studies have suggested that diabetes mellitus (DM) may cause left ventricular (LV) dysfunction directly resulting in increased susceptibility to heart failure. Using pinhole collimators and advances in data processing, gated SPECT was recently adapted to image the rat heart. The present study was aimed to assess this new imaging technique for quantifying LV function and remodeling from the Streptozotocin (STZ) rat model compared to controls. Methods Twenty one rats were randomly assigned to control or diabetic group. Six months after the induction of diabetes by STZ, Pinhole 99 m Tc-sestamibi gated SPECT was performed for determining rat LV volumes and function. Post-mortem histopathologic analysis was performed to evaluate the determinant of LV remodeling in this model. Results After six months, the normalized to body weight LV End-systolic volume was significantly different in diabetic rats compared to controls (0.46 ± 0.02 vs 0.33 ± 0.03 μL/g; p = 0.01). The normalized LV End-diastolic volume was also different in both groups (1.51 ± 0.03 vs 0.88 ± 0.05 μL/g; p = 0.001) and the normalized stroke volume was significantly higher in STZ-rats (1.05 ± 0.02 vs 0.54 ± 0.06 μL/g; p = 0.001). The muscular fibers were thinner at histology in the diabetic rats (0.44 ± 0.07 vs 0.32 ± 0.06 AU; p = 0.01). Conclusion Pinhole 99 m Tc-sestamibi gated SPECT can successfully be applied for the evaluation of cardiac function and remodeling in STZ-induced diabetic rats. In this model, LV volumes were significantly changed compared to a control population, leading to a LV dysfunction. These findings were consistent with the histopathological abnormalities. Finally, these data further suggest the presence of diabetes cardiomyopathy. PMID:17937784

Effects of propranolol treatment on left ventricular function and intracellular calcium regulation in rats with postinfarction heart failure

PubMed Central

Litwin, Sheldon E; Katz, Sarah E; Morgan, James P; Douglas, Pamela S

1999-01-01

Chronic treatment with beta-adrenergic blocking agents can improve survival in patients with heart failure. The mechanisms underlying the beneficial effects and whether these effects are generalizable to ischaemic heart failure are unresolved.We performed echocardiographic-Doppler examinations in rats (n=28) 1 and 6 weeks after myocardial infarction (MI) or sham surgery. Rats were randomized to no treatment or propranolol (500 mg/l in drinking water) after the first echocardiogram. Isometric contractions and intracellular Ca transients were recorded simultaneously in noninfarcted left ventricular (LV) papillary muscles.Untreated MI rats had significant LV dilatation (10.6±0.4* vs 8.9±0.3 mm, MI vs control), impaired systolic function (fractional shortening=11±2* vs 38±2%), and a restrictive LV diastolic filling pattern. MI rats receiving propranolol had similar LV chamber sizes (10.6±0.5 mm) and systolic function (13±2%). The propranolol treated animals had higher LV end-diastolic pressures (27±2* vs 20±3 mmHg) and a more restricted LV diastolic filling pattern (increased ratio of early to late filling velocities and more rapid E wave deceleration rate). Contractility of papillary muscles from untreated MI rats was depressed (1.6±0.3 vs 2.4±0.5 g mm−2). In addition, Ca transients were prolonged and the inotropic response to isoproterenol was blunted. Propranolol treatment did not improve force development (1.6±0.3 g mm−2) or the duration of Ca transients during isoproterenol stimulation.Chronic propranolol treatment in rats with postinfarction heart failure did not improve LV remodeling or systolic function. LV diastolic pressures and filling patterns were worsened by propranolol. Treatment also did not produce appreciable improvement in contractility, intracellular Ca regulation or beta-adrenergic responsiveness in the noninfarcted myocardium. PMID:10455325

The influence of percutaneous closure of patent ductus arteriosus on left ventricular size and function: a prospective study using two- and three-dimensional echocardiography and measurements of serum natriuretic peptides.

PubMed

Eerola, Anneli; Jokinen, Eero; Boldt, Talvikki; Pihkala, Jaana

2006-03-07

We aimed to evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) hemodynamics. Today, most PDAs are closed percutaneously. Little is known, however, about hemodynamic changes after the procedure. Of 37 children (ages 0.6 to 10.6 years) taken to the catheterization laboratory for percutaneous PDA closure, the PDA was closed in 33. Left ventricular diastolic and systolic dimensions, volumes, and function were examined by two-dimensional (2D) and three-dimensional (3D) echocardiography and serum concentrations of natriuretic peptides measured before PDA closure, on the following day, and 6 months thereafter. Control subjects comprised 36 healthy children of comparable ages. At baseline, LV diastolic diameter measured >+2 SD in 5 of 33 patients. In 3D echocardiography, a median LV diastolic volume measured 54.0 ml/m2 in the control subjects and 58.4 ml/m2 (p < 0.05) in the PDA group before closure and 57.2 ml/m2 (p = NS) 6 months after closure. A median N-terminal brain natriuretic peptide (pro-BNP) concentration measured 72 ng/l in the control group and 141 ng/l in the PDA group before closure (p = 0.001) and 78.5 ng/l (p = NS) 6 months after closure. Patients differed from control subjects in indices of LV systolic and diastolic function at baseline. By the end of follow-up, all these differences had disappeared. Even in the subgroup of patients with normal-sized LV at baseline, the LV diastolic volume decreased significantly during follow-up. Changes in LV volume and function caused by PDA disappear by 6 months after percutaneous closure. Even the children with normal-sized LV benefit from the procedure.

Age, Gender and Load-Related Influences on Left Ventricular Geometric Remodeling, Systolic Mid-Wall Function, and NT-ProBNP in Asymptomatic Asian Population.

PubMed

Chen, Chi; Sung, Kuo-Tzu; Shih, Shou-Chuan; Liu, Chuan-Chuan; Kuo, Jen-Yuan; Hou, Charles Jia-Yin; Hung, Chung-Lieh; Yeh, Hung-I

2016-01-01

Advanced age is associated with left ventricle (LV) remodeling and impaired cardiac function that may increase the risk of heart failure. Even so, studies regarding age-related cardiac remodeling in a large, asymptomatic Asian population remain limited. We studied 8,410 asymptomatic participants (49.7 ±11.7 y, 38.9% women) in a health evaluation cohort (2004-2012) at a tertiary center in Northern Taiwan. We analyzed age-related alterations for all echocardiography-derived cardiac structures/functions and the associations with circulating N-terminal prohormone of brain natriuretic peptide (NT-proBNP). We also explored sex-related differences in these measures. In our cohort of 8,410 participants, advanced age was associated with greater LV wall thickness, larger LV total mass (+5.08 g/decade), and greater LV mass index (4.41 g/m2/decade), as well as increased serum NT-proBNP level (+18.89 pg/mL/decade). An accompanying reduction of stress-corrected midwall fractional shortening (-0.1%/decade) with aging was apparent in women after multi-variate adjustment (-0.09%/decade, p = 0.001). Furthermore, women demonstrated greater overall increase in LV wall thickness, LV mass index, and NT-proBNP compared to men (p for interaction: <0.001). All blood pressure components, including systolic, diastolic, and pulse pressures were independently associated with greater wall thickness and LV mass index after adjustment for confounders (all p <0.001). The associations between age and cardiac remodeling or mid-wall functions were further confirmed in a subset of study subjects with repeated follow up by GEE model. Significant associations of unfavorable LV remodeling and advanced age in our asymptomatic Asian population were observed, along with sex differences. These data may help explain the incidence of some diverse gender-related cardiovascular diseases, especially heart failure.

Left atrial physiology and pathophysiology: Role of deformation imaging

PubMed Central

Kowallick, Johannes Tammo; Lotz, Joachim; Hasenfuß, Gerd; Schuster, Andreas

2015-01-01

The left atrium (LA) acts as a modulator of left ventricular (LV) filling. Although there is considerable evidence to support the use of LA maximum and minimum volumes for disease prediction, theoretical considerations and a growing body of literature suggest to focus on the quantification of the three basic LA functions: (1) Reservoir function: collection of pulmonary venous return during LV systole; (2) Conduit function: passage of blood to the left ventricle during early LV diastole; and (3) Contractile booster pump function (augmentation of ventricular filling during late LV diastole. Tremendous advances in our ability to non-invasively characterize all three elements of atrial function include speckle tracking echocardiography (STE), and more recently cardiovascular magnetic resonance myocardial feature tracking (CMR-FT). Corresponding imaging biomarkers are increasingly recognized to have incremental roles in determining prognosis and risk stratification in cardiac dysfunction of different origins. The current editorial introduces the role of STE and CMR-FT for the functional assessment of LA deformation as determined by strain and strain rate imaging and provides an outlook of how this exciting field may develop in the future. PMID:26131333

Prediction of left ventricular dysfunction after device closure of patent ductus arteriosus: proposal for a new functional classification.

PubMed

Kiran, Viralam S; Tiwari, Ashish

2018-04-06

The aims of this study were to determine the incidence and correlates of left ventricular (LV) dysfunction amongst percutaneous patent ductus arteriosus (PDA) device closure patients, and to propose an indexed parameter for predicting LV dysfunction. In a retrospective cross-sectional analysis of 30 months duration, 447 patients who underwent PDA device closure were studied. The diameter of the PDA at the pulmonary artery end was measured in the angiograms in all patients and was indexed for their body surface area. The indexed PDA size was categorised into group A (1-2.9 mm/m², 35/447), B (3-5.9 mm/m², 254/447), C (6-8.9 mm/m², 66/447) and D (>9 mm/m², 35/447). Systolic LV function was evaluated using echocardiography at frequent intervals. Overall, 62.63% of the patients were female (280/447). At baseline, all 447 patients had normal LV function. LV dysfunction was seen in 102/447 (22.8%) patients with 2.8% in category A (1/35), 10.6% in category B (27/254), 34.1% in category C (42/123) and 91.4% in category D (32/35) after PDA device closure. Correlation of indexed PDA size and LV dysfunction was statistically significant (p<0.05). Accurate prediction of LV dysfunction is important in risk stratification, ICU management and counselling in PDA device closures. Indexed PDA size correlates well with post-procedural LV dysfunction. The authors propose a new classification of PDA utilising this accurate, reproducible and easy to perform parameter, which does not involve any extra cost, for risk stratification and early management in device closure of PDA.

Precise identification of endogenous proviruses of NFS/N mice participating in recombination with moloney ecotropic murine leukemia virus (MuLV) to generate polytropic MuLVs.

PubMed

Alamgir, A S M; Owens, Nick; Lavignon, Marc; Malik, Frank; Evans, Leonard H

2005-04-01

Polytropic murine leukemia viruses (MuLVs) are generated by recombination of ecotropic MuLVs with env genes of a family of endogenous proviruses in mice, resulting in viruses with an expanded host range and greater virulence. Inbred mouse strains contain numerous endogenous proviruses that are potential donors of the env gene sequences of polytropic MuLVs; however, the precise identification of those proviruses that participate in recombination has been elusive. Three different structural groups of proviruses in NFS/N mice have been described and different ecotropic MuLVs preferentially recombine with different groups of proviruses. In contrast to other ecotropic MuLVs such as Friend MuLV or Akv that recombine predominantly with a single group of proviruses, Moloney MuLV (M-MuLV) recombines with at least two distinct groups. In this study, we determined that only three endogenous proviruses, two of one group and one of another group, are major participants in recombination with M-MuLV. Furthermore, the distinction between the polytropic MuLVs generated by M-MuLV and other ecotropic MuLVs is the result of recombination with a single endogenous provirus. This provirus exhibits a frameshift mutation in the 3' region of the surface glycoprotein-encoding sequences that is excluded in recombinants with M-MuLV. The sites of recombination between the env genes of M-MuLV and endogenous proviruses were confined to a short region exhibiting maximum homology between the ecotropic and polytropic env sequences and maximum stability of predicted RNA secondary structure. These observations suggest a possible mechanism for the specificity of recombination observed for different ecotropic MuLVs.

Real-Time Three-Dimensional Echocardiography: Characterization of Cardiac Anatomy and Function-Current Clinical Applications and Literature Review Update.

PubMed

Velasco, Omar; Beckett, Morgan Q; James, Aaron W; Loehr, Megan N; Lewis, Taylor G; Hassan, Tahmin; Janardhanan, Rajesh

2017-01-01

Our review of real-time three-dimensional echocardiography (RT3DE) discusses the diagnostic utility of RT3DE and provides a comparison with two-dimensional echocardiography (2DE) in clinical cardiology. A Pubmed literature search on RT3DE was performed using the following key words: transthoracic, two-dimensional, three-dimensional, real-time, and left ventricular (LV) function. Articles included perspective clinical studies and meta-analyses in the English language, and focused on the role of RT3DE in human subjects. Application of RT3DE includes analysis of the pericardium, right ventricular (RV) and LV cavities, wall motion, valvular disease, great vessels, congenital anomalies, and traumatic injury, such as myocardial contusion. RT3DE, through a transthoracic echocardiography (TTE), allows for increasingly accurate volume and valve motion assessment, estimated LV ejection fraction, and volume measurements. Chamber motion and LV mass approximation have been more accurately evaluated by RT3DE by improved inclusion of the third dimension and quantification of volumetric movement. Moreover, RT3DE was shown to have no statistical significance when comparing the ejection fractions of RT3DE to cardiac magnetic resonance (CMR). Analysis of RT3DE data sets of the LV endocardial exterior allows for the volume to be directly quantified for specific phases of the cardiac cycle, ranging from end systole to end diastole, eliminating error from wall motion abnormalities and asymmetrical left ventricles. RT3DE through TTE measures cardiac function with superior diagnostic accuracy in predicting LV mass, systolic function, along with LV and RV volume when compared with 2DE with comparable results to CMR.

Levofloxacin capped Ag-nanoparicles: A new highly selective sensor for cations under joint experimental and DFT investigation

NASA Astrophysics Data System (ADS)

Mondal Roy, Sutapa; Roy, Debesh Ranjan

2017-05-01

A very new and alternate function of an antibiotic drug levofloxacin (Lv), as a highly selective, colorimetric turn-OFF/turn-ON chemosensor for metal-ions Hg2+ and Fe3+, has been reported in this study. An extremely easy, very less time consuming, economical one-pot method of synthesis has been developed for the production of silver nanoparticles (AgNPs). The AgNPs that are stabilized and surface functionalized by Lv. Functionalization of AgNPs by antibiotic drug Lv has been thoroughly confirmed using FTIR spectrophotometry. Two carbonyl oxygen moieties, one belongs to the pyridine oxygen group and another one from the carboxylate oxygen group of Lv together form the binding site over the nanoparticle surface. The Lv-AgNPs system has shown naked eye detectable colour change, as well as significant change via both UV-Vis and fluorescence spectroscopy. The limits of detection (LODs) are predicted to be 6.86 × 10-8 M for Hg2+ and 2.52 × 10-9 M for Fe3+ using UV-Vis spectroscopy and 2.35 × 10-9 M for Fe3+ using fluorescence spectroscopy. UV-Vis spectroscopy, fluorescence spectroscopy, FTIR, TEM, DLS etc. have been used for the physico-chemical characterization of Lv-AgNPs system and the nanoparticle mediated sensing process. Detailed experimental and theoretical studies employing FTIR spectrophotometry and density functional theory (DFT) studies have been used for the elucidation of drug-nanoparticle based sensing mechanism. It is also demonstrated that the Lv-AgNPs system can show real time application using Test-Paper Kit to establish the drug-nanoparticle assembly as a potential colorimetric turn-OFF/turn-ON sensing system for Hg2+ and Fe3+ respectively.

Impact of Preeclampsia on Clinical and Functional Outcomes in Women With Peripartum Cardiomyopathy.

PubMed

Lindley, Kathryn J; Conner, Shayna N; Cahill, Alison G; Novak, Eric; Mann, Douglas L

2017-06-01

Preeclampsia is a risk factor for the development of peripartum cardiomyopathy (PPCM), but it is unknown whether preeclampsia impacts clinical or left ventricular (LV) functional outcomes. This study sought to assess clinical and functional outcomes in women with PPCM complicated by preeclampsia. This retrospective cohort study included women diagnosed with PPCM delivering at Barnes-Jewish Hospital between 2004 to 2014. The primary outcome was one-year event-free survival rate for the combined end point of death and hospital readmission. The secondary outcome was recovery of LV ejection fraction. Seventeen of 39 women (44%) with PPCM had preeclampsia. The groups had similar mean LV ejection fraction at diagnosis (29.6 with versus 27.3 without preeclampsia; P =0.5). Women with preeclampsia had smaller mean LV end-diastolic diameters (5.2 versus 6.0 cm; P =0.001), greater relative wall thickness (0.41 versus 0.35 mm Hg; P =0.009), and lower incidence of eccentric remodeling (12% versus 48%; P =0.03). Clinical follow-up was available for 32 women; 5 died of cardiovascular complications within 1 year of diagnosis (4/15 with versus 1/17 without preeclampsia; P =0.16). In time to event analysis, patients with preeclampsia had worse event-free survival during 1-year follow-up ( P =0.047). Echocardiographic follow-up was available in 10 survivors with and 16 without preeclampsia. LV ejection fraction recovered in 80% of survivors with versus 25% without preeclampsia ( P =0.014). PPCM with concomitant preeclampsia is associated with increased morbidity and mortality and different patterns of LV remodeling and recovery of LV function when compared with patients with PPCM that is not complicated by preeclampsia. © 2017 American Heart Association, Inc.

Effects of gene deletion of the tissue inhibitor of the matrix metalloproteinase-type 1 (TIMP-1) on left ventricular geometry and function in mice

NASA Technical Reports Server (NTRS)

Roten, L.; Nemoto, S.; Simsic, J.; Coker, M. L.; Rao, V.; Baicu, S.; Defreyte, G.; Soloway, P. J.; Zile, M. R.; Spinale, F. G.

2000-01-01

Alterations in the expression and activity of the matrix metalloproteinases (MMPs) and the tissue inhibitors of the MMPs (TIMPs) have been implicated in tissue remodeling in a number of disease states. One of the better characterized TIMPs, TIMP-1, has been shown to bind to active MMPs and to regulate the MMP activational process. The goal of this study was to determine whether deletion of the TIMP-1 gene in mice, which in turn would remove TIMP-1 expression in LV myocardium, would produce time-dependent effects on LV geometry and function. Age-matched sibling mice (129Sv) deficient in the TIMP-1 gene (TIMP-1 knock-out (TIMP-1 KO), n=10) and wild-type mice (n=10) underwent comparative echocardiographic studies at 1 and 4 months of age. LV catheterization studies were performed at 4 months and the LV harvested for histomorphometric studies. LV end-diastolic volume and mass increased (18+/-4 and 38+/-3%, respectively, P<0.05) at 4 months in the TIMP-1 KO group; a significant increase compared to wild-type controls (P<0.05). At 4 months, LV and end-diastolic wall stress was increased by over two-fold in the TIMP-1 KO compared to wild type (P<0.05). However, LV systolic pressure and ejection performance were unchanged in the two groups of mice. LV myocyte cross-sectional area was unchanged in the TIMP-1 KO mice compared to controls, but myocardial fibrillar collagen content was reduced. Changes in LV geometry occurred in TIMP-1 deficient mice and these results suggest that constitutive TIMP-1 expression participates in the maintenance of normal LV myocardial structure. Copyright 2000 Academic Press.

Sildenafil ameliorates right ventricular early molecular derangement during left ventricular pressure overload.

PubMed

Imai, Yousuke; Kariya, Taro; Iwakiri, Masaki; Yamada, Yoshitsugu; Takimoto, Eiki

2018-01-01

Right ventricular (RV) dysfunction following left ventricular (LV) failure is associated with poor prognosis. RV remodeling is thought initiated by the increase in the afterload of RV due to secondary pulmonary hypertension (PH) to impaired LV function; however, RV molecular changes might occur in earlier stages of the disease. cGMP (cyclic guanosine monophosphate)-phosphodiesterase 5 (PDE5) inhibitors, widely used to treat PH through their pulmonary vasorelaxation properties, have shown direct cardiac benefits, but their impacts on the RV in LV diseases are not fully determined. Here we show that RV molecular alterations occur early in the absence of RV hemodynamic changes during LV pressure-overload and are ameliorated by PDE5 inhibition. Two-day moderate LV pressure-overload (transverse aortic constriction) neither altered RV pressure/ function nor RV weight in mice, while it induced only mild LV hypertrophy. Importantly, pathological molecular features were already induced in the RV free wall myocardium, including up-regulation of gene markers for hypertrophy and inflammation, and activation of extracellular signal-regulated kinase (ERK) and calcineurin. Concomitant PDE5 inhibition (sildenafil) prevented induction of such pathological genes and activation of ERK and calcineurin in the RV as well as in the LV. Importantly, dexamethasone also prevented these RV molecular changes, similarly to sildenafil treatment. These results suggest the contributory role of inflammation to the early pathological interventricular interaction between RV and LV. The current study provides the first evidence for the novel early molecular cross-talk between RV and LV, preceding RV hemodynamic changes in LV disease, and supports the therapeutic strategy of enhancing cGMP signaling pathway to treat heart diseases.

Pressure-volume analysis reveals characteristic sex-related differences in cardiac function in a rat model of aortic banding-induced myocardial hypertrophy.

PubMed

Ruppert, Mihály; Korkmaz-Icöz, Sevil; Loganathan, Sivakkanan; Jiang, Weipeng; Lehmann, Lorenz H; Oláh, Attila; Sayour, Alex Ali; Barta, Bálint András; Merkely, Béla; Karck, Matthias; Radovits, Tamás; Szabó, Gábor

2018-05-25

Sex differences in pressure overload (PO)-induced left ventricular (LV) myocardial hypertrophy (LVH) have been intensely investigated. Nevertheless, sex-related disparities of LV hemodynamics in LVH were not examined in detail. Therefore, we aimed to provide a detailed characterization of distinct aspects of LV function in male and female rats during different stages of LVH. Banding of the abdominal aorta (AB) was performed to induce PO for 6 or 12 weeks in male and female rats. Control animals underwent sham operation. The development of LVH was followed by serial echocardiography. Cardiac function was assessed by pressure-volume analysis. Cardiomyocyte hypertrophy and fibrosis were evaluated by histology. At week 6, increased LV mass index, heart weight-to-tibial length, cardiomyocyte diameter, concentric LV geometry and moderate interstitial fibrosis were detected in both male and female AB rats, indicating the development of an early stage of LVH. Functionally, at this time point, impaired active relaxation, increased contractility and preserved ventricular-arterial coupling were observed in the AB groups in both genders. In contrast, at week 12, progressive deterioration of LVH-associated structural and functional alterations occurred in male but not in female animals with sustained PO. Accordingly, at this later stage, LVH was associated with eccentric remodeling, exacerbated fibrosis and increased chamber stiffness in male AB rats. Furthermore, augmented contractility declined in male and not in female AB animals, resulting in contractility-afterload mismatch. Maintained contractility augmentation, preserved ventricular-arterial coupling and better myocardial compliance in female rats contribute to sex differences in LV function during the progression of PO-induced LVH.

Cardiovascular magnetic resonance assessment of ventricular function and myocardial scarring before and early after repair of anomalous left coronary artery from the pulmonary artery

PubMed Central

2014-01-01

Background In patients with anomalous left coronary artery from the pulmonary artery (ALCAPA) left ventricular (LV) dilatation and dysfunction evolves due to diminished myocardial perfusion caused by coronary steal phenomenon. Using late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) imaging, myocardial scarring has been shown in ALCAPA patients late after repair, however the incidence of scarring before surgery and its impact on postoperative course after surgical repair remained unknown. Methods 8 ALCAPA-patients (mean age 10.0 ± 5.8 months) underwent CMR before and early after (mean 4.9 ± 2.5 months) coronary reimplantation procedures. CMR included functional analysis and LGE for detection of myocardial scars. Results LV dilatation (mean LVEDVI 171 ± 94 ml/m2) and dysfunction (mean LV-EF 22 ± 10 %) was present in all patients and improved significantly after surgery (mean LVEDV 68 ± 42 ml/m2, p = 0.02; mean LV-EF 58 ± 19 %, p < 0.001). Preoperative CMR revealed myocardial scarring in 2 of the 8 patients and did not predict postoperative course. At follow-up CMR, one LGE-positive patient showed delayed recovery of LV function while myocardial scarring was still present in both patients. In two patients new-onset transmural scarring was found, although functional recovery after operation was sufficient. One of them showed a stenosis of the left coronary artery and required resurgery. Conclusions Despite diminished myocardial perfusion and severely compromised LV function, myocardial scarring was preoperatively only infrequently present. Improvement of myocardial function was independent of new-onset scarring while the impact of preoperative scarring still needs to be defined. PMID:24387660

Arterial stiffness and wave reflection: sex differences and relationship with left ventricular diastolic function.

PubMed

Russo, Cesare; Jin, Zhezhen; Palmieri, Vittorio; Homma, Shunichi; Rundek, Tatjana; Elkind, Mitchell S V; Sacco, Ralph L; Di Tullio, Marco R

2012-08-01

Increased arterial stiffness and wave reflection have been reported in heart failure with normal ejection fraction (HFNEF) and in asymptomatic left ventricular (LV) diastolic dysfunction, a precursor of HFNEF. It is unclear whether women, who have higher frequency of HFNEF, are more vulnerable than men to the deleterious effects of arterial stiffness on LV diastolic function. We investigated, in a large community-based cohort, whether sex differences exist in the relationship among arterial stiffness, wave reflection, and LV diastolic function. Arterial stiffness and wave reflection were assessed in 983 participants from the Cardiovascular Abnormalities and Brain Lesions study using applanation tonometry. The central pulse pressure/stroke volume index, total arterial compliance, pulse pressure amplification, and augmentation index were used as parameters of arterial stiffness and wave reflection. LV diastolic function was evaluated by 2-dimensional echocardiography and tissue-Doppler imaging. Arterial stiffness and wave reflection were greater in women compared with men, independent of body size and heart rate (all P<0.01), and showed inverse relationships with parameters of diastolic function in both sexes. Further adjustment for cardiovascular risk factors attenuated these relationships; however, a higher central pulse pressure/stroke volume index predicted LV diastolic dysfunction in women (odds ratio, 1.54; 95% confidence intervals, 1.03 to 2.30) and men (odds ratio, 2.09; 95% confidence interval, 1.30 to 3.39), independent of other risk factors. In conclusion, in our community-based cohort study, higher arterial stiffness was associated with worse LV diastolic function in men and women. Women's higher arterial stiffness, independent of body size, may contribute to their greater susceptibility to develop HFNEF.

Impact of basal inferolateral scar burden determined by automatic analysis of 99mTc-MIBI myocardial perfusion SPECT on the long-term prognosis of cardiac resynchronization therapy.

PubMed

Morishima, Itsuro; Okumura, Kenji; Tsuboi, Hideyuki; Morita, Yasuhiro; Takagi, Kensuke; Yoshida, Ruka; Nagai, Hiroaki; Tomomatsu, Toshiro; Ikai, Yoshihiro; Terada, Kazushi; Sone, Takahito; Murohara, Toyoaki

2017-04-01

Left-ventricular (LV) scarring may be associated with a poor response to cardiac resynchronization therapy (CRT). The automatic analysis of myocardial perfusion single-photon emission computed tomography (MP-SPECT) may provide objective quantification of LV scarring. We investigated the impact of LV scarring determined by an automatic analysis of MP-SPECT on short-term LV volume response as well as long-term outcome. We studied consecutive 51 patients who were eligible to undergo 99mTc-MIBI MP-SPECT both at baseline and 6 months after CRT (ischaemic cardiomyopathies 31%). Quantitative perfusion SPECT was used to evaluate the defect extent (an index of global scarring) and the LV 17-segment regional uptake ratio (an inverse index of regional scar burden). The primary outcome was the composite of overall mortality or first hospitalization for worsening heart failure. A high global scar burden and a low mid/basal inferolateral regional uptake ratio were associated with volume non-responders to CRT at 6 months. The basal inferolateral regional uptake ratio remained as a predictor of volume non-response after adjusting for the type of cardiomyopathy. During a median follow-up of 36.1 months, the outcome occurred in 28 patients. The patients with a low basal inferolateral regional uptake ratio with a cutoff value of 57% showed poor prognosis (log-rank P= 0.006). The scarring determined by automatic analysis of MP-SPECT images may predict a poor response to CRT regardless of the pathogenesis of cardiomyopathy. The basal inferolateral scar burden in particular may have an adverse impact on long-term prognosis. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Subclinical left ventricular diastolic dysfunction and incident type 2 diabetes risk: the Korean Genome and Epidemiology Study.

PubMed

Park, Juri; Kim, Jin-Seok; Kim, Seong Hwan; Kim, Sunwon; Lim, Sang Yup; Lim, Hong-Euy; Cho, Goo-Yeong; Sung, Ki-Chul; Kim, Jang-Young; Baik, Inkyung; Koh, Kwang Kon; Lee, Jung Bok; Lee, Seung Ku; Shin, Chol

2017-03-14

Subclinical left ventricular (LV) diastolic dysfunction in type 2 diabetes (T2D) is a common finding and represents an early sign of diabetic cardiomyopathy. However, the relationship between LV diastolic dysfunction and the incident T2D has not been previously studied. A total of 1817 non-diabetic participants (mean age, 54 years; 48% men) from the Korean Genome and Epidemiology Study who were free of cardiovascular disease were studied. LV structure and function were assessed by conventional echocardiography and tissue Doppler imaging. Subclinical LV diastolic dysfunction was defined using age-specific cutoff limits for early diastolic (Em) velocity, mitral E/Em ratio, and left atrial volume index. During the 6-year follow-up period, 273 participants (15%) developed T2D. Participants with incident T2D had greater LV mass index (86.7 ± 16.4 vs. 91.2 ± 17.0 g/m 2 ), worse diastolic function, reflected by lower Em velocity (7.67 ± 1.80 vs. 7.47 ± 1.70) and higher E/Em ratio (9.19 ± 2.55 vs. 10.23 ± 3.00), and higher prevalence of LV diastolic dysfunction (34.6 vs. 54.2%), compared with those who did not develop T2D (all P < 0.001). In a multivariate logistic regression model, lower Em velocity (odd ratio [OR], 0.867; 95% confidence interval [CI] 0.786-0.957) and the presence of LV diastolic dysfunction (OR, 1.617; 95% CI 1.191-2.196) were associated with the development of T2D, after adjusting for potential confounding factors. In a community-based cohort, the presence of subclinical LV diastolic dysfunction was a predictor of the progression to T2D. These data suggest that the echocardiographic assessment of LV diastolic function may be helpful in identifying non-diabetic subjects at risk of incident T2D.

Modelling passive diastolic mechanics with quantitative MRI of cardiac structure and function.

PubMed

Wang, Vicky Y; Lam, H I; Ennis, Daniel B; Cowan, Brett R; Young, Alistair A; Nash, Martyn P

2009-10-01

The majority of patients with clinically diagnosed heart failure have normal systolic pump function and are commonly categorized as suffering from diastolic heart failure. The left ventricle (LV) remodels its structure and function to adapt to pathophysiological changes in geometry and loading conditions, which in turn can alter the passive ventricular mechanics. In order to better understand passive ventricular mechanics, a LV finite element (FE) model was customized to geometric data segmented from in vivo tagged magnetic resonance images (MRI) data and myofibre orientation derived from ex vivo diffusion tensor MRI (DTMRI) of a canine heart using nonlinear finite element fitting techniques. MRI tissue tagging enables quantitative evaluation of cardiac mechanical function with high spatial and temporal resolution, whilst the direction of maximum water diffusion in each voxel of a DTMRI directly corresponds to the local myocardial fibre orientation. Due to differences in myocardial geometry between in vivo and ex vivo imaging, myofibre orientations were mapped into the geometric FE model using host mesh fitting (a free form deformation technique). Pressure recordings, temporally synchronized to the tagging data, were used as the loading constraints to simulate the LV deformation during diastole. Simulation of diastolic LV mechanics allowed us to estimate the stiffness of the passive LV myocardium based on kinematic data obtained from tagged MRI. Integrated physiological modelling of this kind will allow more insight into mechanics of the LV on an individualized basis, thereby improving our understanding of the underlying structural basis of mechanical dysfunction under pathological conditions.

Echocardiographic assessment by computer-assisted analysis of diastolic left ventricular function and hypertrophy in borderline or mild systemic hypertension.

PubMed

Papademetriou, V; Gottdiener, J S; Fletcher, R D; Freis, E D

1985-09-15

Systemic hypertension is a common cause of congestive heart failure. However, left ventricular (LV) systolic function remains normal for many years in patients with mild or moderate hypertension. In this study, high-quality M-mode echocardiograms were recorded in 7 patients with borderline hypertension, 14 patients with mild hypertension and 15 normal persons. Measures of systolic and diastolic LV function and the degree of LV hypertrophy were studied with the assistance of a tablet digitizer and dedicated microcomputer. Average blood pressure was 125 +/- 10/77 +/- 7 mm Hg in normal subjects, 146 +/- 18/92 +/- 2 mm Hg in patients with borderline hypertension and 150 +/- 11/102 +/- 4 in patients with mild hypertension. Indexes of systolic LV function were similar in all 3 groups. The peak rate of early relaxation of the LV posterior wall was significantly decreased in the group of patients with mild hypertension (4.7 vs 6.6 sec-1, p less than 0.01). The mitral valve closure rate was 150 +/- 32 mm/s in normal subjects, 119 +/- 35 mm/s in patients with borderline hypertension and 106 +/- 26 mm/s (p less than 0.001) in patients with mild hypertension. Mild LV hypertrophy was present in 6 of 7 patients with borderline and 13 of 14 patients with mild hypertension. The degree of hypertrophy and the level of blood pressure correlated poorly.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of Left Ventricle Function by Regional Fractional Area Change (RFAC) in a Mouse Model of Myocardial Infarction Secondary to Valsartan Treatment

PubMed Central

Castiglioni, Laura; Colazzo, Francesca; Fontana, Lucia; Colombo, Gualtiero I.; Piacentini, Luca; Bono, Elisa; Milano, Giuseppina; Paleari, Serena; Palermo, Annamaria; Guerrini, Uliano; Tremoli, Elena; Sironi, Luigi

2015-01-01

Aim Left ventricle (LV) regional fractional area change (RFAC) measured by cardiac magnetic resonance (CMR) allows the non-invasive localization and quantification of the degree of myocardial infarction (MI), and could be applied to assess the effectiveness of pharmacological or regenerative therapies. Here we investigate the ability of RFAC to identify regional dysfunction and discriminate the effect of pharmacological treatment with valsartan, a selective antagonist of angiotensin II type 1 receptor, in a model of MI. Methods and Results C57BL/6N mice, undergoing coronary artery ligation, were divided into two groups: untreated (MI) or treated with valsartan (MI+Val). Sham-operated mice were used as a control. Cardiac dimensions and function were assessed at baseline, 24 hours, 1 and 4 weeks post surgery by CMR and echocardiography. At sacrifice histology and whole-genome gene expression profiling were performed. RFAC was able to detect significant differences between treatment groups whereas the global ejection fraction was not. RFAC showed greater loss of regional contraction in remote non-infarcted myocardium in MI group than in MI+Val group. Consistently, in the same region MI+Val mice showed reduced myocyte hypertrophy, fibroblast proliferation, and fibrosis and modulation of target genes; in addition, left atrium volumes, appendage length and duct contraction were preserved. Conclusion In this study, RFAC effectively estimated the degree of systolic dysfunction and discriminated the regions preserved by pharmacological treatment. RFAC index is a promising tool to monitor changes in LV contraction and to assess the effectiveness of therapeutic regimens in clinical settings. PMID:26291973

Alteration of Left Ventricular Function with Dobutamine Challenge in Patients with Myocardial Bridge

PubMed Central

Jhi, Joon-Hyung; Ha, Jong-kun; Jung, Chan-Woo; kim, Bong-Jae; Park, Seong-Oh; Jo, A-Ra; Kim, Seong-Man; Lee, Hyeon-Gook; Kim, Tae-Ik

2011-01-01

Background/Aims The aim of this study was to identify changes in left ventricular (LV) performance in patients with a myocardial bridge (MB) in the left anterior descending coronary artery during resting and in an inotropic state. Methods Myocardial strain measurement by speckle-tracking echocardiography and conventional LV wall-motion scoring was performed in 18 patients with MB (mean age, 48.1 ± 1.7 years, eight female) during resting and intravenous dobutamine challenge (10 and 20 µg/kg/min). Results Conventional LV wall-motion scoring was normal in all patients during resting and in an inotropic state. Peak regional circumferential strain increased dose dependently upon dobutamine challenge. Longitudinal strains of the anterior and anteroseptal segments were, however, reduced at 20 µg/kg/min and showed a dyssynchronous pattern at 20 µg/kg/min. Although there were no significant differences in radial strain and displacement of all segments at rest compared with under 10 µg/kg/min challenge, radial strain and displacement of anterior segments at 20 µg/kg/min were significantly reduced compared with posterior segments at the papillary muscle level (44.8 ± 14.9% vs. 78.4 ± 20.1% and 5.3 ± 2.3 mm vs. 8.5 ± 1.8 mm, respectively; all p < 0.001), and showed plateau (40%) or biphasic (62%) patterns. Conclusions Reduced LV strain of patients with MB after inotropic stimulation was identified. Speckle-tracking strain echocardiography identified a LV myocardial dyssynchrony that was not demonstrated by conventional echocardiography in patients with MB. PMID:22205841

Empiric versus imaging guided left ventricular lead placement in cardiac resynchronization therapy (ImagingCRT): study protocol for a randomized controlled trial.

PubMed

Sommer, Anders; Kronborg, Mads Brix; Poulsen, Steen Hvitfeldt; Böttcher, Morten; Nørgaard, Bjarne Linde; Bouchelouche, Kirsten; Mortensen, Peter Thomas; Gerdes, Christian; Nielsen, Jens Cosedis

2013-04-26

Cardiac resynchronization therapy (CRT) is an established treatment in heart failure patients. However, a large proportion of patients remain nonresponsive to this pacing strategy. Left ventricular (LV) lead position is one of the main determinants of response to CRT. This study aims to clarify whether multimodality imaging guided LV lead placement improves clinical outcome after CRT. The ImagingCRT study is a prospective, randomized, patient- and assessor-blinded, two-armed trial. The study is designed to investigate the effect of imaging guided left ventricular lead positioning on a clinical composite primary endpoint comprising all-cause mortality, hospitalization for heart failure, or unchanged or worsened functional capacity (no improvement in New York Heart Association class and <10% improvement in six-minute-walk test). Imaging guided LV lead positioning is targeted to the latest activated non-scarred myocardial region by speckle tracking echocardiography, single-photon emission computed tomography, and cardiac computed tomography. Secondary endpoints include changes in LV dimensions, ejection fraction and dyssynchrony. A total of 192 patients are included in the study. Despite tremendous advances in knowledge with CRT, the proportion of patients not responding to this treatment has remained stable since the introduction of CRT. ImagingCRT is a prospective, randomized study assessing the clinical and echocardiographic effect of multimodality imaging guided LV lead placement in CRT. The results are expected to make an important contribution in the pursuit of increasing response rate to CRT. Clinicaltrials.gov identifier NCT01323686. The trial was registered March 25, 2011 and the first study subject was randomized April 11, 2011.

Resting multilayer 2D speckle-tracking TTE for detection of ischemic segments confirmed by invasive FFR part-2, using post-systolic-strain-index and time from aortic-valve-closure to regional peak longitudinal-strain.

PubMed

Ozawa, Koya; Funabashi, Nobusada; Nishi, Takeshi; Takahara, Masayuki; Fujimoto, Yoshihide; Kamata, Tomoko; Kobayashi, Yoshio

2016-08-15

This study evaluated the post-systolic strain index (PSI), and the time interval between aortic valve closure (AVC) and regional peak longitudinal strain (PLS), measured by transthoracic echocardiography (TTE), for detection of left ventricular (LV) myocardial ischemic segments confirmed by invasive fractional flow reserve (FFR). 39 stable patients (32 males; 65.8±11.9years) with 46 coronary arteries at ≥50% stenosis on invasive coronary angiography underwent 2D speckle tracking TTE (Vivid E9, GE Healthcare) and invasive FFR measurements. PSI, AVC and regional PLS in each LV segment were calculated. FFR ≤0.80 was detected in 27 LV segments. There were no significant differences between segments supplied by FFR ≤0.80 and FFR >0.80 vessels in either PSI or the time interval between AVC and regional PLS. To identify LV segments±FFR ≤0.80, the receiver operator characteristic (ROC) curves for PSI, and the time interval between AVC and regional PLS had areas under the curve (AUC) values of 0.58 and 0.57, respectively, with best cut-off points of 12% (sensitivity 70.4%, specificity 57.9%) and 88ms (sensitivity 70.4%, specificity 52.6%), respectively, but the AUCs were not statistically significant. In stable coronary artery disease patients with ≥50% coronary artery stenosis, measurement of PSI, and the time interval between AVC and regional PLS, on resting TTE, enabled the identification of LV segments with FFR ≤0.80 using each appropriate threshold for PSI, and the time interval between AVC and regional PLS, with reasonable diagnostic accuracy. However, the AUC values were not statistically significant. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Cardiovascular function is better in veteran football players than age-matched untrained elderly healthy men.

PubMed

Schmidt, J F; Andersen, T R; Andersen, L J; Randers, M B; Hornstrup, T; Hansen, P R; Bangsbo, J; Krustrup, P

2015-02-01

The aim of the study was to determine whether lifelong football training may improve cardiovascular function, physical fitness, and body composition. Our subjects were 17 male veteran football players (VPG; 68.1 ± 2.1 years) and 26 healthy age-matched untrained men who served as a control group (CG; 68.2 ± 3.2 years). Examinations included measurements of cardiac function, microvascular endothelial function [reactive hyperemic index (RHI)], maximum oxygen uptake (VO2max), and body composition. In VPG, left ventricular (LV) end-diastolic volume was 20% larger (P < 0.01) and LV ejection fraction was higher (P < 0.001). Tissue Doppler imaging revealed an augmented LV longitudinal displacement, i.e., LV shortening of 21% (P < 0.001) and longitudinal 2D strain was 12% higher (P < 0.05), in VPG. In VPG, resting heart rate was lower (6 bpm, P < 0.05), and VO2max was higher (18%, P < 0.05). In addition, RHI was 21% higher (P < 0.05) in VPG. VPG also had lower body mass index (P < 0.05), body fat percentage, total body fat mass, android fat percentage, and gynoid fat percentage (all P < 0.01). Lifelong participation in football training is associated with better LV systolic function, physical fitness, microvascular function, and a healthier body composition. Overall, VPG have better cardiovascular function compared with CG, which may reduce their cardiovascular morbidity and mortality. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Improvement of cardiac function persists long term with medical therapy for left ventricular systolic dysfunction.

PubMed

Chen, David; Chang, Richard; Umakanthan, Branavan; Stoletniy, Liset N; Heywood, J Thomas

2007-09-01

In certain patients with left ventricular (LV) systolic dysfunction, improvements in cardiac function are seen after initiation of medical therapy; however, the long-term stability of ventricular function in such patients is not well described. We retrospectively analyzed 171 patients who had a baseline ejection fraction of 45% or less, a follow-up echocardiogram at 2 to 12 months after initiation of medical therapy, and a final echocardiogram. We found that 48.5% of the patients demonstrated initial improvements in LV function after initiation of medical therapy, and the improvements appear to be sustained (88% of patients) at 44 +/- 21 months follow-up. A nonischemic etiology and younger age were the only independent predictors of change of LV ejection fraction of 10 or more at a mean 8.4 +/- 3.4 months after optimal medical therapy. Our study revealed a trend toward improved long-term survival in individuals with an early improvement in LV ejection fraction with medical therapy, especially in those with sustained improvement.

Impact of chronic obstructive pulmonary diseases on left ventricular diastolic function in hospitalized elderly patients.

PubMed

Huang, Ying-Shuo; Feng, Ying-Chao; Zhang, Jian; Bai, Li; Huang, Wei; Li, Min; Sun, Ying

2015-01-01

To evaluate the impact of chronic obstructive pulmonary disease (COPD) on left ventricular (LV) diastolic function in hospitalized elderly patients. This was a case-control observational study of 148 consecutive hospitalized elderly patients (≥65 years old): 73 subjects without COPD as controls and 75 patients with COPD. Mild-to-moderate COPD was defined as stages 1 and 2, while severe and very severe COPD was defined as stages 3 and 4, according to the Global Initiative for Chronic Obstructive Lung Disease guidelines. Clinical characteristics and echocardiographic parameters were analyzed and compared. Compared with the control group, patients with COPD had a higher frequency of LV diastolic dysfunction and heart failure with preserved ejection fraction. Smoking frequency, frequency of cerebrovascular diseases and diabetes, and serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were higher in the COPD group (all P<0.05). COPD patients showed more abnormalities in diastolic function (E/e': 11.51±2.50 vs 10.42±3.25, P=0.047), but no differences in systolic function and right ventricular function (all P>0.05). Patients with severe/very severe COPD showed no differences in LV diastolic function compared to patients with mild/moderate COPD (P>0.05), but serum NT-proBNP levels were higher in severe/very severe COPD (P<0.05). Results suggest that early-stage COPD may have an impact on the LV diastolic function. Severe COPD mainly affected right ventricular function. In hospitalized elderly patients with COPD, LV diastolic dysfunction should be taken into account together with right ventricular function.

Left ventricular rotation and torsion in patients with perimembranous ventricular septal defect.

PubMed

Zhuang, Yan; Yong, Yong-hong; Yao, Jing; Ji, Ling; Xu, Di

2014-03-01

Assessment of left ventricular (LV) rotation has become an important approach for quantifying LV function. In this study, we sought to analyze LV rotation and twist using speckle tracking imaging (STI) in adult patients with isolated ventricular septal defects. Using STI, the peak rotation and time to peak rotation of 6 segments in basal and apical short-axis were measured, respectively, in 32 patients with ventricular septal defect and 30 healthy subjects as controls. The global rotation of the 6 segments in basal and apical and LV twist versus time profile were drawn, the peak rotation and twist of LV were calculated. All the time to peak rotation/twist were expressed as a percentage of end-systole (end-systole = 100%). Left ventricular ejection fraction was measured by biplane Simpson method. In patients group, the peak rotation of posterior, inferior, and postsept wall in basal was higher(P ≤ 0.05) and LV twist was also higher (P ≤ 0.05) than healthy controls. There were no significant differences between 2 groups in the peak rotation of the other 9 segments and left ventricular ejection fraction. Different from the control group, the time to peak rotation of the 6 segments in basal were delayed and the global rotation of the base was delayed (P ≤ 0.05) in ventricular septal defect group. Left ventricular volume overload due to ventricular septal defect has significant effect on LV rotation and twist, and LV rotation and twist may be a new index predicting LV systolic function. © 2013, Wiley Periodicals, Inc.

Predictors of Renal Denervation Efficacy in the Treatment of Resistant Hypertension.

PubMed

Ripp, Tatiana M; Mordovin, Victor F; Pekarskiy, Stanislav E; Ryabova, Tamara R; Zlobina, Marina V; Baev, Andrei E; Anfinogenova, Yana; Popov, Sergey V

2015-12-01

The aims of the study were to evaluate the effects of renal sympathetic denervation (RSD) on the heart and to identify the predictors of RSD efficacy in patients with resistant arterial hypertension. The study comprised 60 RSD patients (54.6 ± 9.5 years) who received full-dose antihypertensive therapy (4.1 drugs) including diuretics. Initially, 58.6% of patients had abnormal left ventricular (LV) diastolic function. All patients received echocardiography before and 24 weeks after RSD. Renal sympathetic denervation was achieved through the endovascular radiofrequency ablation (RFA) of the renal arteries. Drug therapy continued for the entire period of observation. After RSD, all patients were retrospectively assigned to two groups: group 1 comprised patients (n = 22; 36.7%) in whom the myocardial mass (MM) of the left ventricle decreased by more than 10 g after RSD; group 2 comprised patients (n = 38; 63.3%) in whom LV MM increased or decreased by less than 10 g. Anthropometry, arterial blood pressure, heart rate, therapy, and LV end-diastolic dimensions (EDD) were comparable in these groups. After RSD, the values of office blood pressure significantly decreased and MM regressed by more than 10 g in 36.7% of patients; LV diastolic function normalized in 31% of patients, and diastolic dysfunction improved in 14% of patients. The study found the associations between the initial LV wall dimensions and LV MM changes. Unlike LV EDD, arterial blood pressure, or heart rate, the initial values of LV wall thickness predicted LV MM regress. #NCT01499810 https://clinicaltrials.gov/ct2/show/NCT01499810.

Are endogenous feline leukemia viruses really endogenous?

PubMed

Stewart, H; Jarrett, O; Hosie, M J; Willett, B J

2011-10-15

Full length endogenous feline leukemia virus (FeLV) proviruses exist within the genomes of many breeds of domestic cat raising the possibility that they may also exist in a transmissible exogenous form. Such viruses would share receptor usage with the recombinant FeLV-B subgroup, a viral subgroup that arises in vivo by recombination between exogenous subgroup A virus (FeLV-A) and endogenous FeLV. Accordingly, all isolates of FeLV-B made to date have contained a "helper" FeLV-A, consistent with their recombinatorial origin. In order to assess whether endogenous viruses are transmitted between cats, we examined primary isolates of FeLV for which the viral subgroup had been determined for the presence of a subgroup B virus that lacked an FeLV-A. Here we describe the identification of two primary field isolates of FeLV (2518 and 4314) that appeared to contain subgroup B virus only by classical interference assays, raising the possibility of between-host transmission of endogenous FeLV. Sequencing of the env gene and U3 region of the 3' long terminal repeat (LTR) confirmed that both viral genomes contained endogenous viral env genes. However the viral 3' LTRs appeared exogenous in origin with a putative 3' recombination breakpoint residing at the 3' end of the env gene. Further, the FeLV-2518 virions also co-packaged a truncated FeLV-A genome containing a defective env gene, termed FeLV-2518(A) whilst no helper subgroup A viral genome was detected in virions of FeLV-4314. The acquisition of an exogenous LTR by the endogenous FeLV in 4314 may have allowed a recombinant FeLV variant to outgrow an exogenous FeLV-A virus that was presumably present during first infection. Given time, a similar evolution may also occur within the 2518 isolate. The data suggest that endogenous FeLVs may be mobilised by acquisition of exogenous LTRs yielding novel viruses that type biologically as FeLV-B. Copyright © 2011 Elsevier B.V. All rights reserved.

Subclinical Cardiotoxicity Detected by Strain Rate Imaging up to 14 months After Breast Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erven, Katrien, E-mail: katrien.erven@uzleuven.be; Iridium Cancer Network, Antwerp; Florian, Anca

Purpose: Strain rate imaging (SRI) is a new echocardiographic modality that enables accurate measurement of regional myocardial function. We investigated the role of SRI and troponin I (TnI) in the detection of subclinical radiation therapy (RT)-induced cardiotoxicity in breast cancer patients. Methods and Materials: This study prospectively included 75 women (51 left-sided and 24 right-sided) receiving adjuvant RT to the breast/chest wall and regional lymph nodes. Sequential echocardiographs with SRI were obtained before RT, immediately after RT, and 8 and 14 months after RT. TnI levels were measured on the first and last day of RT. Results: Mean heart andmore » left ventricle (LV) doses were both 9 ± 4 Gy for the left-sided patients and 4 ± 4 Gy and 1 ± 0.4 Gy, respectively, for the right-sided patients. A decrease in strain was observed at all post-RT time points for left-sided patients (−17.5% ± 1.9% immediately after RT, −16.6% ± 1.4% at 8 months, and −17.7% ± 1.9% at 14 months vs −19.4% ± 2.4% before RT, P<.01) but not for right-sided patients. When we considered left-sided patients only, the highest mean dose was given to the anterior left ventricular (LV) wall (25 ± 14 Gy) and the lowest to the inferior LV wall (3 ± 3 Gy). Strain of the anterior wall was reduced after RT (−16.6% ± 2.3% immediately after RT, −16% ± 2.6% at 8 months, and −16.8% ± 3% at 14 months vs −19% ± 3.5% before RT, P<.05), whereas strain of the inferior wall showed no significant change. No changes were observed with conventional echocardiography. Furthermore, mean TnI levels for the left-sided patients were significantly elevated after RT compared with before RT, whereas TnI levels of the right-sided patients remained unaffected. Conclusions: In contrast to conventional echocardiography, SRI detected a regional, subclinical decline in cardiac function up to 14 months after breast RT. It remains to be determined whether these changes are related to clinical outcome. In the meantime, we encourage the use of radiation techniques that minimize the exposure of the anterior LV wall in left-sided patients.« less

Presence of Tube isoforms in Litopenaeus vannamei suggests various regulatory patterns of signal transduction in invertebrate NF-κB pathway.

PubMed

Li, Chaozheng; Chen, Yixiao; Weng, Shaoping; Li, Sedong; Zuo, Hongliang; Yu, Xiaoqiang; Li, Haoyang; He, Jianguo; Xu, Xiaopeng

2014-02-01

The toll-like receptor (TLR)/NF-κB signaling pathways play critical roles in the innate immune system. The intracellular signal transduction of most TLR pathways in invertebrate cells is triggered by formation of a heterotrimeric complex composed of MyD88, Tube and Pelle. In this study, we identified a Litopenaeus vannamei Pelle (LvPelle) and an isoform of L. vannamei Tube (LvTube) designated as LvTube-1. The interactions among LvPelle, LvTube/LvTube-1 and LvMyD88/LvMyD88-1 were elucidated and their functions during pathogen infections were investigated. Knockdowns of LvPelle and LvTube/LvTube-1 using RNAi strategy led to higher mortalities of shrimps during Vibrio parahemolyticus infection, and could reduce the genome copy number of white spot syndrome virus (WSSV) in the infected muscle tissue but did not affect the mortality caused by WSSV infection. The effects of LvPelle and LvTube/LvTube-1 on promoters containing NF-κB binding motifs were analyzed by dual-luciferase reporter assays and the results demonstrated that LvTube-1 could activate the NF-κB activity to significantly higher level than LvTube did. Moreover, tissue distributions of LvTube and LvTube-1 mRNAs and their expression profiles during pathogen and immune stimulant challenges were different, indicating that they could play different roles in immune responses. This is the first report of Tube isoforms in invertebrates. Together with our previous study on LvMyD88 isoforms, our results suggest that various isoforms of adaptor components may be involved in various regulatory patterns of signal transduction in invertebrate TLR/NF-κB pathway and this could be a strategy adopted by invertebrates to modulate immune responses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pharmacological prevention of reperfusion injury in acute myocardial infarction. A potential role for adenosine as a therapeutic agent.

PubMed

Quintana, Miguel; Kahan, Thomas; Hjemdahl, Paul

2004-01-01

The concept of reperfusion injury, although first recognized from animal studies, is now recognized as a clinical phenomenon that may result in microvascular damage, no-reflow phenomenon, myocardial stunning, myocardial hibernation and ischemic preconditioning. The final consequence of this event is left ventricular (LV) systolic dysfunction leading to increased morbidity and mortality. The typical clinical case of reperfusion injury occurs in acute myocardial infarction (MI) with ST segment elevation in which an occlusion of a major epicardial coronary artery is followed by recanalization of the artery. This may occur either spontaneously or by means of thrombolysis and/or by primary percutaneous coronary intervention (PCI) with efficient platelet inhibition by aspirin (acetylsalicylic acid), clopidogrel and glycoprotein IIb/IIIa inhibitors. Although the pathophysiology of reperfusion injury is complex, the major role that neutrophils play in this process is well known. Neutrophils generate free radicals, degranulation products, arachidonic acid metabolites and platelet-activating factors that interact with endothelial cells, inducing endothelial injury and neutralization of nitrous oxide vasodilator capacity. Adenosine, through its multi-targeted pharmacological actions, is able to inhibit some of the above-mentioned detrimental effects. The net protective of adenosine in in vivo models of reperfusion injury is the reduction of the infarct size, the improvement of the regional myocardial blood flow and of the regional function of the ischemic area. Additionally, adenosine preserves the post-ischemic coronary flow reserve, coronary blood flow and the post-ischemic regional contractility. In small-scale studies in patients with acute MI, treatment with adenosine has been associated with smaller infarcts, less no-reflow phenomenon and improved LV function. During elective PCI adenosine reduced ST segment shifts, lactate production and ischemic symptoms. During the last years, three relatively large placebo-controlled clinical trials have been conducted: Acute Myocardial Infarction Study of Adenosine Trial (AMISTAD) I and II and Attenuation by Adenosine of Cardiac Complications (ATTACC). In the AMISTAD trials, the final infarct size was reduced and the LV systolic function was improved by adenosine treatment, mainly in patients with anterior MI localization. However, morbidity and mortality were not affected. In the ATTACC study, the LV systolic function was not affected by adenosine, however, trends towards improved survival were observed in patients with anterior MI localization. The possibility of obtaining a Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in the infarct-related artery in up to 95% of patients with acute MI (increasing the occurrence of reperfusion injury) has turned back the interest towards the protection of myocardial cells from the impending ischemic and reperfusion injury in which adenosine alone or together with other cardio-protective agents may exert important clinical effects.

Impaired global myocardial flow dynamics despite normal left ventricular function and regional perfusion in chronic kidney disease: a quantitative analysis of clinical 82Rb PET/CT studies.

PubMed

Fukushima, Kenji; Javadi, Mehrbod S; Higuchi, Takahiro; Bravo, Paco E; Chien, David; Lautamäki, Riikka; Merrill, Jennifer; Nekolla, Stephan G; Bengel, Frank M

2012-06-01

Impaired global myocardial flow reserve (MFR) may be associated with increased risk for cardiac events and coronary artery disease progression. Chronic kidney disease (CKD) is also considered a risk factor for cardiovascular disease. We sought to investigate the effect of CKD on the myocardial microcirculation in patients referred for clinical (82)Rb PET/CT, who had normal left ventricular (LV) function and no flow-limiting coronary artery disease. Estimated glomerular filtration rate (eGFR) was available for 230 patients who had undergone rest and pharmacologic stress (82)Rb PET/CT for suspected coronary artery disease. CKD was defined as an eGFR less than 60 mL/min/1.73 m(2). After patients with hemodialysis, a renal transplant, abnormal regional perfusion (summed stress score > 4), or reduced LV function (LV ejection fraction < 45%) were excluded, 40 CKD patients remained. Those were compared with a control group without CKD, which was matched for age, sex, coronary risk factors, and systemic hemodynamics (n = 42). List-mode acquisition of PET enabled quantification of myocardial blood flow (MBF) and MFR using a previously validated retention model with correction for (82)Rb extraction. Rest MBF was normalized to rate-pressure product. Mean eGFR in the CKD group was reduced (44 ± 14 vs. 99 ± 28 mL/min/1.73 m(2); P < 0.0001), and creatinine was significantly elevated, compared with controls (1.9 ± 1.1 vs. 0.8 ± 0.2 mg/dL; P < 0.0001). MFR was significantly reduced in CKD (2.2 ± 1.0 vs. 3.0 ± 1.2 for controls; P = 0.027). This reduction was mainly due to increased rest MBF (1.1 ± 0.4 in CKD vs. 0.8 ± 0.2 mL/min/g in controls; P = 0.007). Stress myocardial flow was comparable between both groups (2.3 ± 0.9 vs. 2.3 ± 0.8 mL/min/g; P = 0.08). Overall, MFR was significantly correlated with eGFR (r = 0.41; P = 0.0005). Stress MBF did not correlate with eGFR (r = 0.002; P = 0.45), but rest MBF showed an inverse correlation (r = -0.49; P < 0.0001). Rest MBF was also inversely correlated with hemoglobin (r = -0.28; P = 0.014), but only eGFR was an independent correlate at multivariate analysis. MFR is impaired in patients with renal insufficiency with normal regional perfusion and LV function, mostly because of elevated rest flow. Absolute quantification of flow may be useful to identify microvascular dysfunction as a precursor of clinically overt coronary disease in this specific risk group.

The impact of a hyperdynamic left ventricle on right ventricular function measurements in preterm infants with a patent ductus arteriosus.

PubMed

Breatnach, Colm R; Franklin, Orla; James, Adam T; McCallion, Naomi; El-Khuffash, Afif

2017-09-01

Right ventricular (RV) functional assessment in premature infants includes basal longitudinal strain (RV BLS), RV systolic tissue Doppler velocity (RV s'), tricuspid annular plane systolic excursion (TAPSE) and RV fractional area change (FAC). A hyperdynamic left ventricle (LV) may influence RV measures of displacement (TAPSE) and velocity (RV s') but not measures of relative change of length (RV BLS) or area (FAC). We aimed to explore this hypothesis in preterm infants with a patent ductus arteriosus (PDA). We measured LV function (ejection fraction (LV EF); left ventricular output) and RV function (RV BLS; RV s'; TAPSE; FAC) on days 1, 2 and 5-7 in infants <29 weeks. The cohort was divided based on PDA presence by days 5-7. LV and RV function measurements were compared between the groups using two-way analysis of variance with repeated measures. 121 infants with a mean (SD) gestation and birth weight of 26.8 (1.4) weeks and 968 (250) g were enrolled. By days 5-7, the PDA remained open in 83 (69%), with evidence of hyperdynamic LV function. There was no difference in RV s' (5.3 (0.9) vs 5.1 (1.0) cm/s, p=0.3) or TAPSE (6.2 (1.3) vs 6.1 (1.2) mm, p=0.7) between infants with and without a PDA, but infants in the PDA group had lower RV FAC (41 (8) vs 47 (10) %, p<0.01) and lower RV BLS (-24.2 (5.0) vs -26.2 (4.1) %, p=0.03). LV influence on RV functional parameters must be taken into account when interpreting of RV function using those techniques. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Myocardial Infarct Segmentation from Magnetic Resonance Images for Personalized Modeling of Cardiac Electrophysiology

PubMed Central

Ukwatta, Eranga; Arevalo, Hermenegild; Li, Kristina; Yuan, Jing; Qiu, Wu; Malamas, Peter; Wu, Katherine C.

2016-01-01

Accurate representation of myocardial infarct geometry is crucial to patient-specific computational modeling of the heart in ischemic cardiomyopathy. We have developed a methodology for segmentation of left ventricular (LV) infarct from clinically acquired, two-dimensional (2D), late-gadolinium enhanced cardiac magnetic resonance (LGE-CMR) images, for personalized modeling of ventricular electrophysiology. The infarct segmentation was expressed as a continuous min-cut optimization problem, which was solved using its dual formulation, the continuous max-flow (CMF). The optimization objective comprised of a smoothness term, and a data term that quantified the similarity between image intensity histograms of segmented regions and those of a set of training images. A manual segmentation of the LV myocardium was used to initialize and constrain the developed method. The three-dimensional geometry of infarct was reconstructed from its segmentation using an implicit, shape-based interpolation method. The proposed methodology was extensively evaluated using metrics based on geometry, and outcomes of individualized electrophysiological simulations of cardiac dys(function). Several existing LV infarct segmentation approaches were implemented, and compared with the proposed method. Our results demonstrated that the CMF method was more accurate than the existing approaches in reproducing expert manual LV infarct segmentations, and in electrophysiological simulations. The infarct segmentation method we have developed and comprehensively evaluated in this study constitutes an important step in advancing clinical applications of personalized simulations of cardiac electrophysiology. PMID:26731693

Association of dietary iron restriction with left ventricular remodeling after myocardial infarction in mice.

PubMed

Eguchi, Akiyo; Naito, Yoshiro; Iwasaku, Toshihiro; Okuhara, Yoshitaka; Morisawa, Daisuke; Sawada, Hisashi; Nishimura, Koichi; Oboshi, Makiko; Fujii, Kenichi; Mano, Toshiaki; Masuyama, Tohru; Hirotani, Shinichi

2016-02-01

Several epidemiologic studies have reported that body iron status and dietary iron intake are related to an increased risk of acute myocardial infarction (MI). However, it is completely unknown whether dietary iron reduction impacts the development of left ventricular (LV) remodeling after MI. Here, we investigate the effect of dietary iron restriction on the development of LV remodeling after MI in an experimental model. MI was induced in C57BL/6 J mice (9-11 weeks of age) by the permanent ligation of the left anterior descending coronary artery (LAD). At 2 weeks after LAD ligation, mice were randomly divided into two groups and were given a normal diet or an iron-restricted diet for 4 weeks. Sham operation without LAD ligation was also performed as controls. MI mice exhibited increased LV dilatation and impaired LV systolic function that was associated with cardiomyocyte hypertrophy and interstitial fibrosis in the remote area, as compared with the controls at 6 weeks after MI. In contrast, dietary iron restriction attenuated LV dilatation and impaired LV systolic function coupled to cardiomyocyte hypertrophy and interstitial fibrosis in the remote area. Importantly, cardiac expression of cellular iron transport proteins, transferrin receptor 1 and divalent metal transporter 1 was increased in the remote area of MI mice compared with the controls. Dietary iron restriction attenuated the development of LV remodeling after MI in mice. Cellular iron transport might play a role in the pathophysiological mechanism of LV remodeling after MI.

Left ventricular eccentricity index measured with SPECT myocardial perfusion imaging: An additional parameter of adverse cardiac remodeling.

PubMed

Gimelli, Alessia; Liga, Riccardo; Clemente, Alberto; Marras, Gavino; Kusch, Annette; Marzullo, Paolo

2017-01-12

Single-photon emission computed-tomography (SPECT) allows the quantification of LV eccentricity index (EI), a measure of cardiac remodeling. We sought to evaluate the feasibility of EI measurement with SPECT myocardial perfusion imaging and its interactions with relevant LV functional and structural parameters. Four-hundred and fifty-six patients underwent myocardial perfusion imaging on a Cadmium-Zinc-Telluride (CZT) camera. The summed rest, stress, and difference scores were calculated. From rest images, the LV end-diastolic (EDV) and end-systolic volumes, ejection fraction (EF), and peak filling rate (PFR) were calculated. In every patient, the EI, ranging from 0 (sphere) to 1 (line), was computed using a dedicated software (QGS/QPS; Cedars-Sinai Medical Center). Three-hundred and thirty-eight/456 (74%) patients showed a normal EF (>50%), while 26% had LV systolic dysfunction. The EI was computed from CZT images with excellent reproducibility (interclass correlation coefficient: 0.99, 95% CI 0.98-0.99). More impaired EI values correlated with the presence of a more abnormal LV perfusion (P < .001), function (EF and PFR, P < .001), and structure (EDV, P < .001). On multivariate analysis, higher EDV (P < .001) and depressed EF (P = .014) values were independent predictors of abnormal EI. The evaluation of LV eccentricity is feasible on gated CZT images. Abnormal EI associates with significant cardiac structural and functional abnormalities.

Outcomes of Left Ventricular Function According to Treatment Response for a Patent Ductus Arteriosus in Preterm Infants.

PubMed

Kang, Soo Jung; Cho, Young Sun; Hwang, Seo Jung; Kim, Hyo Jin

2017-12-01

To evaluate the outcomes of left ventricular (LV) function according to treatment response for a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Echocardiograms of 21 preterm infants born at gestational age < 31 weeks obtained at term-equivalent age were retrospectively studied. Among preterm infants with a hsPDA, 9 underwent ligation after failure of pharmacological closure (ligation group) and 6 experienced successful pharmacological closure (medication group). Six preterm infants without hsPDA (no-hsPDA group) were studied as controls. LV peak longitudinal systolic strain (ε) of each infant was retrospectively obtained from echocardiograms using velocity vector imaging, along with neonatal outcomes. Pharmacological closures were attempted at postnatal day 2-3. In the ligation group, the median postnatal age at ligation was 20 days. In the ligation group, LV peak longitudinal systolic ε was significantly decreased at term-equivalent age compared to the other groups. Between the medication and no-hsPDA groups, LV peak longitudinal systolic ε did not differ significantly. Among the neonatal outcomes, infants who experienced necrotizing enterocolitis (NEC) showed significantly decreased LV peak longitudinal systolic ε compared to the infants who did not experience NEC . We speculate that in preterm infants with an hsPDA, in cases of medical treatment failure, early PDA ligation at less than 20 days of postnatal age would be beneficial for preserving LV systolic function.

Insights from Novel Noninvasive CT and ECG Imaging Modalities on Electromechanical Myocardial Activation in a Canine Model of Ischemic Dyssynchronous Heart Failure.

PubMed

Dawoud, Fady; Schuleri, Karl H; Spragg, David D; Horáček, B Milan; Berger, Ronald D; Halperin, Henry R; Lardo, Albert C

2016-12-01

The interplay between electrical activation and mechanical contraction patterns is hypothesized to be central to reduced effectiveness of cardiac resynchronization therapy (CRT). Furthermore, complex scar substrates render CRT less effective. We used novel cardiac computed tomography (CT) and noninvasive electrocardiographic imaging (ECGI) techniques in an ischemic dyssynchronous heart failure (DHF) animal model to evaluate electrical and mechanical coupling of cardiac function, tissue viability, and venous accessibility of target pacing regions. Ischemic DHF was induced in 6 dogs using coronary occlusion, left bundle ablation and tachy RV pacing. Full body ECG was recorded during native rhythm followed by volumetric first-pass and delayed enhancement CT. Regional electrical activation were computed and overlaid with segmented venous anatomy and scar regions. Reconstructed electrical activation maps show consistency with LBBB starting on the RV and spreading in a "U-shaped" pattern to the LV. Previously reported lines of slow conduction are seen parallel to anterior or inferior interventricular grooves. Mechanical contraction showed large septal to lateral wall delay (80 ± 38 milliseconds vs. 123 ± 31 milliseconds, P = 0.0001). All animals showed electromechanical correlation except dog 5 with largest scar burden. Electromechanical decoupling was largest in basal lateral LV segments. We demonstrated a promising application of CT in combination with ECGI to gain insight into electromechanical function in ischemic dyssynchronous heart failure that can provide useful information to study regional substrate of CRT candidates. © 2016 Wiley Periodicals, Inc.

Low intrinsic exercise capacity in rats predisposes to age-dependent cardiac remodeling independent of macrovascular function

PubMed Central

Ritchie, Rebecca H.; Leo, Chen Huei; Qin, Chengxue; Stephenson, Erin J.; Bowden, Marissa A.; Buxton, Keith D.; Lessard, Sarah J.; Rivas, Donato A.; Koch, Lauren G.; Britton, Steven L.; Woodman, Owen L.

2013-01-01

Rats selectively bred for low (LCR) or high (HCR) intrinsic running capacity simultaneously present with contrasting risk factors for cardiovascular and metabolic disease. However, the impact of these phenotypes on left ventricular (LV) morphology and microvascular function, and their progression with aging, remains unresolved. We tested the hypothesis that the LCR phenotype induces progressive age-dependent LV remodeling and impairments in microvascular function, glucose utilization, and β-adrenergic responsiveness, compared with HCR. Hearts and vessels isolated from female LCR (n = 22) or HCR (n = 26) were studied at 12 and 35 wk. Nonselected N:NIH founder rats (11 wk) were also investigated (n = 12). LCR had impaired glucose tolerance and elevated plasma insulin (but not glucose) and body-mass at 12 wk compared with HCR, with early LV remodeling. By 35 wk, LV prohypertrophic and glucose transporter GLUT4 gene expression were up- and downregulated, respectively. No differences in LV β-adrenoceptor expression or cAMP content between phenotypes were observed. Macrovascular endothelial function was predominantly nitric oxide (NO)-mediated in both phenotypes and remained intact in LCR for both age-groups. In contrast, mesenteric arteries microvascular endothelial function, which was impaired in LCR rats regardless of age. At 35 wk, endothelial-derived hyperpolarizing factor-mediated relaxation was impaired whereas the NO contribution to relaxation is intact. Furthermore, there was reduced β2-adrenoceptor responsiveness in both aorta and mesenteric LCR arteries. In conclusion, diminished intrinsic exercise capacity impairs systemic glucose tolerance and is accompanied by progressive development of LV remodeling. Impaired microvascular perfusion is a likely contributing factor to the cardiac phenotype. PMID:23262135

Neuromodulation therapy does not influence blood flow distribution or left-ventricular dynamics during acute myocardial ischemia.

PubMed

Kingma, J G; Linderoth, B; Ardell, J L; Armour, J A; DeJongste, M J; Foreman, R D

2001-08-13

Electrical stimulation of the dorsal aspect of the upper thoracic spinal cord is used increasingly to treat patients with angina pectoris refractory to conventional therapeutic strategies. The purpose of this study was to determine whether spinal cord stimulation (SCS) in dogs affects regional myocardial blood flow and left-ventricular (LV) function before and during transient obstruction of the left anterior descending coronary artery (LAD). In anesthetized dogs, regional myocardial blood flow distribution was determined using radiolabeled microspheres and left-ventricular function was measured by impedance-derived pressure-volume loops. SCS was accomplished by stimulating the dorsal T1-T2 segments of the spinal cord using epidural bipolar electrodes at 90% of motor threshold (MT) (50 Hz, 0.2-ms duration). Effects of 5-min SCS were assessed under basal conditions and during 4-min occlusion of the LAD. SCS alone evoked no change in regional myocardial blood flow or cardiovascular indices. Transient LAD occlusion significantly diminished blood flow within ischemic, but not in non-ischemic myocardial tissue. Left ventricular pressure-volume loops were shifted rightward during LAD occlusion. Cardiac indices were altered similarly during LAD occlusion and concurrent SCS. SCS does not influence the distribution of blood flow within the non-ischemic or ischemic myocardium. Nor does it modify LV pressure-volume dynamics in the anesthetized experimental preparation.

Non-invasive electromechanical activation imaging as a tool to study left ventricular dyssynchronous patients: Implication for CRT therapy.

PubMed

Dawoud, Fady; Spragg, David D; Berger, Ronald D; Cheng, Alan; Horáček, B Milan; Halperin, Henry R; Lardo, Albert C

2016-01-01

Electromechanical de-coupling is hypothesized to explain non-response of dyssynchrony patient to cardiac resynchronization therapy (CRT). In this pilot study, we investigated regional electromechanical uncoupling in 10 patients referred for CRT using two non-invasive electrical and mechanical imaging techniques (CMR tissue tracking and ECGI). Reconstructed regional electrical and mechanical activation captured delayed LBBB propagation direction from septal to anterior/inferior and finally to lateral walls as well as from LV apical to basal. All 5 responders demonstrated significantly delayed mechanical and electrical activation on the lateral LV wall at baseline compared to the non-responders (P<.05). On follow-up ECGI, baseline electrical activation patterns were preserved in native rhythm and global LV activation time was reduced with biventricular pacing. The combination of novel imaging techniques of ECGI and CMR tissue tracking can be used to assess spatial concordance of LV electrical and mechanical activation to gain insight into electromechanical coupling. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of left ventricular function in anesthetized patients using femoral artery dP/dt(max).

PubMed

De Hert, Stefan G; Robert, Dominique; Cromheecke, Stefanie; Michard, Frédéric; Nijs, Jan; Rodrigus, Inez E

2006-06-01

The purpose of this study was to compare dP/dt(max) estimated from a femoral artery pressure tracing to left ventricular (LV) dP/dt(max) during various alterations in myocardial loading and contractile function. Seventy patients scheduled for elective coronary artery bypass surgery. All patients were instrumented with a high-fidelity LV catheter, a pulmonary artery catheter, and a femoral arterial catheter. In 40 patients, hemodynamic measurements were performed before and after passive leg raising and before and after calcium administration (5 mg/kg); and in 30 other patients, hemodynamic measurements were performed before and after dobutamine infusion (5 microg/kg/min over 10 minutes). LV and femoral dP/dt(max) were significantly correlated (r = 0.82, p < 0.001), but femoral dP/dt(max) systematically underestimated LV dP/dt(max) (bias = -361 +/- 96 mmHg/s). Passive leg raising induced significant increases in central venous pressure and LV end-diastolic pressure, but femoral dP/dt(max), stroke volume, and LV dP/dt(max) remained unaltered. Calcium administration induced significant and marked increases in LV dP/dt(max) (23% +/- 9%) and femoral dP/dt(max) (37% +/- 14%) associated with a significant increase in stroke volume (9% +/- 2%). Dobutamine infusion also induced significant and marked increases in LV dP/dt(max) (25% +/- 8%) and femoral dP/dt(max) (35% +/- 12%) associated with a significant increase in stroke volume (14% +/- 3%). Overall, a very close linear relationship (r = 0.93) and a good agreement (bias = -5 +/- 17 mmHg/s) were found between changes in LV dP/dt(max) and changes in femoral dP/dt(max). A very close relationship was also observed between changes in LV dP/dt(max) and changes in femoral dP/dt(max) during each intervention (leg raising, calcium administration, and dobutamine infusion). Femoral dP/dt(max) underestimated LV dP/dt(max), but changes in femoral dP/dt(max) accurately reflected changes in LV dP/dt(max) during various interventions.

An Echocardiographic Study of Left Ventricular Size and Cardiac Function in Adolescent Females with Anorexia Nervosa.

PubMed

Escudero, Carolina A; Potts, James E; Lam, Pei-Yoong; De Souza, Astrid M; Mugford, Gerald J; Sandor, George G S

2016-01-01

This retrospective case-control study investigated cardiac dimensions and ventricular function in female adolescents with anorexia nervosa (AN) compared with controls. Echocardiographic measurements of left ventricular (LV) dimensions, LV mass index, left atrial size and cardiac index were made. Detailed measures of systolic and diastolic ventricular function were made including tissue Doppler imaging. Patients were stratified by body mass index ≤10th percentile (AN ≤ 10th) and >10th percentile (AN > 10th). Ninety-five AN patients and 58 controls were included. AN and AN ≤ 10th groups had reduced LV dimensions, LV mass index, left atrial size and cardiac index compared with controls. There were no differences between groups in measures of systolic function. Measures of diastolic tissue Doppler imaging were decreased in AN and AN ≤ 10th. No differences in echocardiographic measurements existed between controls and AN > 10th. Female adolescents with AN have preserved systolic function and abnormalities of diastolic ventricular function. AN ≤ 10th may be a higher risk group. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.

Evaluation of longitudinal left ventricular function in patients with coronary artery ectasia and vitamin D deficiency by 2D speckle tracking echocardiography.

PubMed

Aghajani, Hasan; Faal, Mohsen; Hosseinsabet, Ali

2017-03-01

Coronary artery ectasia (CAE) is defined as the dilation of at least one segment of the coronary arteries that reaches at least 1.5 times the size of a normal neighboring segment. It has been shown that left ventricular (LV) diastolic function is impaired in patients with CAE. Also, it has been shown that LV function is impaired in vitamin D-deficient subjects compared with vitamin D-sufficient subjects and vitamin D deficiency is prevalent in CAE patients. We hypothesized that LV function is impaired in patients with CAE so we evaluated longitudinal LV myocardial function by 2D speckle tracking echocardiography (2DSTE) in patients with CAE and vitamin D deficiency without significant coronary artery stenosis and compared the results with those of subjects with vitamin D deficiency and near-normal coronary arteries. Our study population comprised 21 consecutive patients with CAE and without significant coronary artery stenosis (<50%) and 31 control subjects with near-normal coronary arteries. All subjects had vitamin D deficiency. All 2DSTE-derived indices of longitudinal LV function, comprised of the absolute values of systolic strain (14.0±2.7% vs 15.4±2.3%, P=.039), systolic strain rate (1.2±0.2/s vs 1.3±0.2/s, P=.015), early diastolic strain rate (1.1±0.3/s vs 1.3±0.3 s -1 , P=.030), and late diastolic strain rate (0.8±0.2/s vs 1±0.2/s , P=.005), were reduced in the patients with CAE and vitamin D deficiency. The systolic and diastolic functions of the LV in the patients with CAE and vitamin D deficiency were impaired as evaluated by 2DSTE. © 2017, Wiley Periodicals, Inc.

Associations of electrocardiographic P-wave characteristics with left atrial function, and diffuse left ventricular fibrosis defined by cardiac magnetic resonance: The PRIMERI Study.

PubMed

Tiffany Win, Theingi; Ambale Venkatesh, Bharath; Volpe, Gustavo J; Mewton, Nathan; Rizzi, Patricia; Sharma, Ravi K; Strauss, David G; Lima, Joao A; Tereshchenko, Larisa G

2015-01-01

Abnormal P-terminal force in lead V1 (PTFV1) is associated with an increased risk of heart failure, stroke, atrial fibrillation, and death. Our goal was to explore associations of left ventricular (LV) diffuse fibrosis with left atrial (LA) function and electrocardiographic (ECG) measures of LA electrical activity. Patients without atrial fibrillation (n = 91; mean age 59.5 years; 61.5% men; 65.9% white) with structural heart disease (spatial QRS-T angle ≥105° and/or Selvester QRS score ≥5 on ECG) but LV ejection fraction >35% underwent clinical evaluation, cardiac magnetic resonance, and resting ECG. LA function indices were obtained by multimodality tissue tracking using 2- and 4-chamber long-axis images. T1 mapping and late gadolinium enhancement were used to assess diffuse LV fibrosis and presence of scar. P-prime in V1 amplitude (PPaV1) and duration (PPdV1), averaged P-wave-duration, PR interval, and P-wave axis were automatically measured using 12 SLTM algorithm. PTFV1 was calculated as a product of PPaV1 and PPdV1. In linear regression after adjustment for demographic characteristics, body mass index, maximum LA volume index, presence of scar, and LV mass index, each decile increase in LV interstitial fibrosis was associated with 0.76 mV*ms increase in negative abnormal PTFV1 (95% confidence interval [CI] -1.42 to -0.09; P = .025), 15.3 ms prolongation of PPdV1 (95% CI 6.9 to 23.8; P = .001) and 5.4 ms prolongation of averaged P-duration (95% CI 0.9-10.0; P = .020). LV fibrosis did not affect LA function. PPaV1 and PTFV1 were associated with an increase in LA volumes and decrease in LA emptying fraction and LA reservoir function. LV interstitial fibrosis is associated with abnormal PTFV1, prolonged PPdV1, and P-duration, but does not affect LA function. Copyright © 2015 Heart Rhythm Society. All rights reserved.

Dehydration reduces left ventricular filling at rest and during exercise independent of twist mechanics.

PubMed

Stöhr, Eric J; González-Alonso, José; Pearson, James; Low, David A; Ali, Leena; Barker, Horace; Shave, Rob

2011-09-01

The purpose of this study was to determine whether the reduction in stroke volume (SV), previously shown to occur with dehydration and increases in internal body temperatures during prolonged exercise, is caused by a reduction in left ventricular (LV) function, as indicated by LV volumes, strain, and twist ("LV mechanics"). Eight healthy men [age: 20 ± 2, maximal oxygen uptake (VO₂max): 58 ± 7 ml·kg⁻¹·min⁻¹] completed two, 1-h bouts of cycling in the heat (35°C, 50% peak power) without fluid replacement, resulting in 2% and 3.5% dehydration, respectively. Conventional and two-dimensional speckle-tracking echocardiography was used to determine LV volumes, strain, and twist at rest and during one-legged knee-extensor exercise at baseline, both levels of dehydration, and following rehydration. Progressive dehydration caused a significant reduction in end-diastolic volume (EDV) and SV at rest and during one-legged knee-extensor exercise (rest: Δ-33 ± 14 and Δ-21 ± 14 ml, respectively; exercise: Δ-30 ± 10 and Δ-22 ± 9 ml, respectively, during 3.5% dehydration). In contrast to the marked decline in EDV and SV, systolic and diastolic LV mechanics were either maintained or even enhanced with dehydration at rest and during knee-extensor exercise. We conclude that dehydration-induced reductions in SV at rest and during exercise are the result of reduced LV filling, as reflected by the decline in EDV. The concomitant maintenance of LV mechanics suggests that the decrease in LV filling, and consequently ejection, is likely caused by the reduction in blood volume and/or diminished filling time rather than impaired LV function.

Left ventricular remodeling and change of systolic function after closure of patent ductus arteriosus in adults: device and surgical closure.

PubMed

Jeong, Young-Hoon; Yun, Tae-Jin; Song, Jong-Min; Park, Jung-Jun; Seo, Dong-Man; Koh, Jae-Kon; Lee, Se-Whan; Kim, Mi-Jeong; Kang, Duk-Hyun; Song, Jae-Kwan

2007-09-01

Left ventricular (LV) remodeling and predictors of LV systolic function late after closure of patent ductus arteriosus (PDA) in adults remain to be clearly demonstrated. In 45 patients with PDA, including 28 patients who received successful occlusion using the Amplatzer device (AD group) (AGA, Golden Valley, MN) and 17 patients who received surgical closure (OP group), echocardiography studies were performed before closure and 1 day (AD group) or within 7 days (OP group) after closure, and then were repeated at > or = 6 months (17 +/- 13 months). In both groups, LV ejection fraction (EF) and end-diastolic volume index were significantly decreased immediately after closure, whereas end-systolic volume index did not change. During the long-term follow-up period, end-systolic as well as end-diastolic volume indices decreased significantly in both groups and LV EF recovered compared to the immediate postclosure state. However, LV EF remained low compared to the preclosure state. Five patients (11.1%) including 3 patients in the AD group and 2 patients in the OP group showed persistent late LV systolic dysfunction (EF <50%). In stepwise, multiple logistic regression analysis, preclosure EF was the only independent predictor of late normal postclosure EF (odds ratio, 1.230; 95% CI, 1.054-1.434; P = .008). Receiver operating characteristic curve analysis showed that preclosure EF > or = 62% had a sensitivity of 72% and a specificity of 83% for predicting late normal LV EF after closure. Left ventricular EF remains low late after PDA closure compared with preclosure state in adults. Preclosure LV EF is the best index to predict late postclosure LV EF.

Left ventricular remodeling in preclinical experimental mitral regurgitation of dogs.

PubMed

Dillon, A Ray; Dell'Italia, Louis J; Tillson, Michael; Killingsworth, Cheryl; Denney, Thomas; Hathcock, John; Botzman, Logan

2012-03-01

Dogs with experimental mitral regurgitation (MR) provide insights into the left ventricular remodeling in preclinical MR. The early preclinical left ventricular (LV) changes after mitral regurgitation represent progressive dysfunctional remodeling, in that no compensatory response returns the functional stroke volume (SV) to normal even as total SV increases. The gradual disease progression leads to mitral annulus stretch and enlargement of the regurgitant orifice, further increasing the regurgitant volume. Remodeling with loss of collagen weave and extracellular matrix (ECM) is accompanied by stretching and hypertrophy of the cross-sectional area and length of the cardiomyocyte. Isolated ventricular cardiomyocytes demonstrate dysfunction based on decreased cell shortening and reduced intracellular calcium transients before chamber enlargement or decreases in contractility in the whole heart can be clinically appreciated. The genetic response to increased end-diastolic pressure is down-regulation of genes associated with support of the collagen and ECM and up-regulation of genes associated with matrix remodeling. Experiments have not demonstrated any beneficial effects on remodeling from treatments that decrease afterload via blocking the renin-angiotensin system (RAS). Beta-1 receptor blockade and chymase inhibition have altered the progression of the LV remodeling and have supported cardiomyocyte function. The geometry of the LV during the remodeling provides insight into the importance of regional differences in responses to wall stress. Copyright © 2012 Elsevier B.V. All rights reserved.

Impact of chronic obstructive pulmonary diseases on left ventricular diastolic function in hospitalized elderly patients

PubMed Central

Huang, Ying-Shuo; Feng, Ying-Chao; Zhang, Jian; Bai, Li; Huang, Wei; Li, Min; Sun, Ying

2015-01-01

Objective To evaluate the impact of chronic obstructive pulmonary disease (COPD) on left ventricular (LV) diastolic function in hospitalized elderly patients. Methods This was a case–control observational study of 148 consecutive hospitalized elderly patients (≥65 years old): 73 subjects without COPD as controls and 75 patients with COPD. Mild-to-moderate COPD was defined as stages 1 and 2, while severe and very severe COPD was defined as stages 3 and 4, according to the Global Initiative for Chronic Obstructive Lung Disease guidelines. Clinical characteristics and echocardiographic parameters were analyzed and compared. Results Compared with the control group, patients with COPD had a higher frequency of LV diastolic dysfunction and heart failure with preserved ejection fraction. Smoking frequency, frequency of cerebrovascular diseases and diabetes, and serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were higher in the COPD group (all P<0.05). COPD patients showed more abnormalities in diastolic function (E/e′: 11.51±2.50 vs 10.42±3.25, P=0.047), but no differences in systolic function and right ventricular function (all P>0.05). Patients with severe/very severe COPD showed no differences in LV diastolic function compared to patients with mild/moderate COPD (P>0.05), but serum NT-proBNP levels were higher in severe/very severe COPD (P<0.05). Conclusion Results suggest that early-stage COPD may have an impact on the LV diastolic function. Severe COPD mainly affected right ventricular function. In hospitalized elderly patients with COPD, LV diastolic dysfunction should be taken into account together with right ventricular function. PMID:25565790

Longitudinal comparison of low- and high-velocity resistance training in relation to body composition and functional fitness of older adults.

PubMed

Gray, Michelle; Powers, Melissa; Boyd, Larissa; Garver, Kayla

2018-03-22

Functional mobility disability affects more than one in five adults over 70 years and increases to 80% by 90 years. While negative changes in mobility are multifactorial, deleterious body composition changes contribute significantly. Resistance training alters the negative trajectory of physical function as well as increases lean mass among older adults. Recently, high-velocity (HV) resistance training has been indicated as an effective intervention to increase lean mass and functional performance. The present investigation compared body composition, physical function, and muscular strength changes between HV and LV resistance training programs. Participants > 65 years (n = 53) were randomly assigned to LV, HV, or active control (AC) group and participated in their respective intervention for 48 weeks. Analysis of covariance revealed no significant body composition changes over time between groups (p > 0.05). Eight-foot up-and-go performance improved in the HV and AC groups (p < 0.05) with no change in the LV group (p > 0.05) over time. Muscular strength increased in both the LV and HV groups within the first 24 weeks, while only in the LV group, muscular strength continued to increase from 24 to 48 weeks (p < 0.05). Resistance training appears to be an effective intervention for improving aspects of physical function and muscular strength; however, no significant changes in body composition were observed over the 48-week intervention. Findings from the current investigation support use of resistance training for improving physical function among community-dwelling older adults.

Associations Between Left Ventricular Dysfunction and Brain Structure and Function: Findings From the SABRE (Southall and Brent Revisited) Study.

PubMed

Park, Chloe M; Williams, Emily D; Chaturvedi, Nish; Tillin, Therese; Stewart, Robert J; Richards, Marcus; Shibata, Dean; Mayet, Jamil; Hughes, Alun D

2017-04-18

Subclinical left ventricular (LV) dysfunction has been inconsistently associated with early cognitive impairment, and mechanistic pathways have been poorly considered. We investigated the cross-sectional relationship between LV dysfunction and structural/functional measures of the brain and explored the role of potential mechanisms. A total of 1338 individuals (69±6 years) from the Southall and Brent Revisited study underwent echocardiography for systolic (tissue Doppler imaging peak systolic wave) and diastolic (left atrial diameter) assessment. Cognitive function was assessed and total and hippocampal brain volumes were measured by magnetic resonance imaging. Global LV function was assessed by circulating N-terminal pro-brain natriuretic peptide. The role of potential mechanistic pathways of arterial stiffness, atherosclerosis, microvascular disease, and inflammation were explored. After adjusting for age, sex, and ethnicity, lower systolic function was associated with lower total brain (beta±standard error, 14.9±3.2 cm 3 ; P <0.0001) and hippocampal volumes (0.05±0.02 cm 3 , P =0.01). Reduced diastolic function was associated with poorer working memory (-0.21±0.07, P =0.004) and fluency scores (-0.18±0.08, P =0.02). Reduced global LV function was associated with smaller hippocampal volume (-0.10±0.03 cm 3 , P =0.004) and adverse visual memory (-0.076±0.03, P =0.02) and processing speed (0.063±0.02, P =0.006) scores. Separate adjustment for concomitant cardiovascular risk factors attenuated associations with hippocampal volume and fluency only. Further adjustment for the alternative pathways of microvascular disease or arterial stiffness attenuated the relationship between global LV function and visual memory. In a community-based sample of older people, measures of LV function were associated with structural/functional measures of the brain. These associations were not wholly explained by concomitant risk factors or potential mechanistic pathways. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Association of Cardiac Troponin T With Left Ventricular Structure and Function in CKD

PubMed Central

Mishra, Rakesh K.; Li, Yongmei; DeFilippi, Christopher; Fischer, Michael J.; Yang, Wei; Keane, Martin; Chen, Jing; He, Jiang; Kallem, Radhakrishna; Horwitz, Ed; Rafey, Mohammad; Raj, Dominic S.; Go, Alan S.; Shlipak, Michael G.

2013-01-01

Background Serum cardiac troponin T (cTnT) is associated with increased risk of heart failure and cardiovascular death in several population settings. We evaluated associations of cTnT with cardiac structural and functional abnormalities in a cohort of chronic kidney disease (CKD) patients without heart failure. Study Design Cross-sectional. Setting & Participants Chronic Renal Insufficiency Cohort (CRIC; N= 3,243) Predictor The primary predictor was cTnT. Secondary predictors included demographic and clinical characteristics, hemoglobin level, high-sensitivity C-reactive protein, and estimated glomerular filtration rate using cystatin C. Outcomes Echocardiography was used to determine left ventricular (LV) mass and LV systolic and diastolic function. Measurements Circulating cTnT was measured in stored sera using the highly sensitive assay. Logistic and linear regression models were used to examine associations of cTnT with each echocardiographic outcome. Results cTnT was detectable in 2,735 (84%) persons; the median was 13.3 (IQR, 7.7–23.8) pg/mL. Compared with undetectable cTnT (<3.0 pg/mL), the highest quartile (23.9 – 738.7 pg/mL) was associated with approximately two times as likely to experience LV hypertrophy (OR, 2.43; 95% CI, 1.44–4.09) in the fully adjusted model. cTnT had a more modest association with LV systolic dysfunction; as a log-linear variable, a significant association was present in the fully adjusted model (OR of 1.4 [95% CI, 1.1–1.7] per 1-log unit; p<0.01). There was no significant independent association between cTnT and LV diastolic dysfunction. When evaluated as a screening test, cTnT functioned only modestly for LV hypertrophy and concentric hypertrophy detection (area under the curve, 0.64 for both) with weaker areas under the curve for the other outcomes. Limitations The presence of coronary artery disease was not formally assessed using either noninvasive or angiographic techniques in this study. Conclusions In this large CKD cohort without heart failure, detectable cTnT had a strong association with LV hypertrophy, a more modest association with LV systolic dysfunction, and no association with diastolic dysfunction. These findings indicate that circulating cTnT levels in CKD are predominantly an indicator of pathological LV hypertrophy. PMID:23291148

Association of cardiac troponin T with left ventricular structure and function in CKD.

PubMed

Mishra, Rakesh K; Li, Yongmei; DeFilippi, Christopher; Fischer, Michael J; Yang, Wei; Keane, Martin; Chen, Jing; He, Jiang; Kallem, Radhakrishna; Horwitz, Edward J; Rafey, Mohammad; Raj, Dominic S; Go, Alan S; Shlipak, Michael G

2013-05-01

Serum cardiac troponin T (cTnT) is associated with increased risk of heart failure and cardiovascular death in several population settings. We evaluated associations of cTnT levels with cardiac structural and functional abnormalities in a cohort of patients with chronic kidney disease (CKD) without heart failure. Cross-sectional. Chronic Renal Insufficiency Cohort (CRIC; N=3,243). The primary predictor was cTnT level. Secondary predictors included demographic and clinical characteristics, hemoglobin level, high-sensitivity C-reactive protein level, and estimated glomerular filtration rate using cystatin C. Echocardiography was used to determine left ventricular (LV) mass and LV systolic and diastolic function. Circulating cTnT was measured in stored sera using the highly sensitive assay. Logistic and linear regression models were used to examine associations of cTnT level with each echocardiographic outcome. cTnT was detectable in 2,735 (84%) persons; median level was 13.3 (IQR, 7.7-23.8) pg/mL. Compared with undetectable cTnT (<3.0 pg/mL), the highest quartile (23.9-738.7 pg/mL) was approximately 2 times as likely to have LV hypertrophy (OR, 2.43; 95% CI, 1.44-4.09) in the fully adjusted model. cTnT level had a more modest association with LV systolic dysfunction; as a log-linear variable, a significant association was present in the fully adjusted model (OR of 1.4 [95% CI, 1.2-1.7] per 1-log unit; P < 0.001). There was no significant independent association between cTnT level and LV diastolic dysfunction. When evaluated as a screening test, cTnT level functioned only modestly for LV hypertrophy and concentric hypertrophy detection (area under the curve, 0.64 for both), with weaker areas under the curve for the other outcomes. The presence of coronary artery disease was not formally assessed using either noninvasive or angiographic techniques in this study. In this large CKD cohort without heart failure, detectable cTnT had a strong association with LV hypertrophy, a more modest association with LV systolic dysfunction, and no association with diastolic dysfunction. These findings indicate that circulating cTnT levels in patients with CKD are predominantly an indicator of pathologic LV hypertrophy. Published by Elsevier Inc.

Estimation of left ventricular operating stiffness from Doppler early filling deceleration time in humans.

PubMed

Garcia, M J; Firstenberg, M S; Greenberg, N L; Smedira, N; Rodriguez, L; Prior, D; Thomas, J D

2001-02-01

Shortened early transmitral deceleration times (E(DT)) have been qualitatively associated with increased filling pressure and reduced survival in patients with cardiac disease and increased left ventricular operating stiffness (K(LV)). An equation relating K(LV) quantitatively to E(DT) has previously been described in a canine model but not in humans. During several varying hemodynamic conditions, we studied 18 patients undergoing open-heart surgery. Transesophageal echocardiographic two-dimensional volumes and Doppler flows were combined with high-fidelity left atrial (LA) and left ventricular (LV) pressures to determine K(LV). From digitized Doppler recordings, E(DT) was measured and compared against changes in LV and LA diastolic volumes and pressures. E(DT) (180 +/- 39 ms) was inversely associated with LV end-diastolic pressures (r = -0.56, P = 0.004) and net atrioventricular stiffness (r = -0.55, P = 0.006) but had its strongest association with K(LV) (r = -0.81, P < 0.001). K(LV) was predicted assuming a nonrestrictive orifice (K(nonrest)) from E(DT) as K(nonrest) = (0.07/E(DT))(2) with K(LV) = 1.01 K(nonrest) - 0.02; r = 0.86, P < 0.001, DeltaK (K(nonrest) - K(LV)) = 0.02 +/- 0.06 mm Hg/ml. In adults with cardiac disease, E(DT) provides an accurate estimate of LV operating stiffness and supports its application as a practical noninvasive index in the evaluation of diastolic function.

Estimation of left ventricular operating stiffness from Doppler early filling deceleration time in humans

NASA Technical Reports Server (NTRS)

Garcia, M. J.; Firstenberg, M. S.; Greenberg, N. L.; Smedira, N.; Rodriguez, L.; Prior, D.; Thomas, J. D.

2001-01-01

Shortened early transmitral deceleration times (E(DT)) have been qualitatively associated with increased filling pressure and reduced survival in patients with cardiac disease and increased left ventricular operating stiffness (K(LV)). An equation relating K(LV) quantitatively to E(DT) has previously been described in a canine model but not in humans. During several varying hemodynamic conditions, we studied 18 patients undergoing open-heart surgery. Transesophageal echocardiographic two-dimensional volumes and Doppler flows were combined with high-fidelity left atrial (LA) and left ventricular (LV) pressures to determine K(LV). From digitized Doppler recordings, E(DT) was measured and compared against changes in LV and LA diastolic volumes and pressures. E(DT) (180 +/- 39 ms) was inversely associated with LV end-diastolic pressures (r = -0.56, P = 0.004) and net atrioventricular stiffness (r = -0.55, P = 0.006) but had its strongest association with K(LV) (r = -0.81, P < 0.001). K(LV) was predicted assuming a nonrestrictive orifice (K(nonrest)) from E(DT) as K(nonrest) = (0.07/E(DT))(2) with K(LV) = 1.01 K(nonrest) - 0.02; r = 0.86, P < 0.001, DeltaK (K(nonrest) - K(LV)) = 0.02 +/- 0.06 mm Hg/ml. In adults with cardiac disease, E(DT) provides an accurate estimate of LV operating stiffness and supports its application as a practical noninvasive index in the evaluation of diastolic function.

Identification and functional characterization of a solute carrier family 15, member 4 gene in Litopenaeus vannamei.

PubMed

Chen, Yong-Gui; Yuan, Kai; Zhang, Ze-Zhi; Yuan, Feng-Hua; Weng, Shao-Ping; Yue, Hai-Tao; He, Jian-Guo; Chen, Yi-Hong

2016-04-01

Innate immunity in shrimp is important in resisting bacterial infection. The NF-κB pathway is pivotal in such an immune response. This study cloned and functionally characterized the solute carrier family (SLC) 15 member A 4 (LvSLC15A4) gene in Litopenaeus vannamei. The open reading frame of LvSLC15A4 is 1, 902 bp long and encodes a putative 633-amino acid protein, which is localized in the plasma membrane and intracellular vesicular compartments. Results of the reporter gene assay showed that LvSLC15A4 upregulated NF-κB target genes, including the immediate-early gene 1 of white spot syndrome virus, as well as several antimicrobial peptide genes, such as pen4, CecA, AttA, and Mtk in S2 cells. Moreover, knocked-down expression of LvSLC15A4 reduced pen4 expression in L. vannamei. LvSLC15A4 down-regulation also increased the cumulative mortality of Vibrio parahemolyticus-infected L. vannamei. Furthermore, LvSLC15A4 expression was induced by unfolded protein response (UPR) in L. vannamei hematocytes. These results suggest that LvSLC15A4 participates in L. vannamei innate immunity via the NF-κB pathway and thus may be related to UPR. Copyright © 2015 Elsevier Ltd. All rights reserved.

Loss or Inhibition of uPA or MMP-9 Attenuates LV Remodeling and Dysfunction after Acute Pressure Overload in Mice

PubMed Central

Heymans, Stephane; Lupu, Florea; Terclavers, Sven; Vanwetswinkel, Bjorn; Herbert, Jean-Marc; Baker, Andrew; Collen, Desire; Carmeliet, Peter; Moons, Lieve

2005-01-01

Left ventricular (LV) hypertrophy is a natural response of the heart to increased pressure loading, but accompanying fibrosis and dilatation may result in irreversible life-threatening heart failure. Matrix metalloproteinases (MMPs) have been invoked in various cardiac diseases, however, direct genetic evidence for a role of the plasminogen activator (PA) and MMP systems in pressure overload-induced LV hypertrophy and in heart failure is lacking. Therefore, the consequences of transverse aortic banding (TAB) were analyzed in mice lacking tissue-type PA (t-PA−/−), urokinase-type PA (u-PA−/−), or gelatinase-B (MMP-9−/−), and in wild-type (WT) mice after adenoviral gene transfer of the PA-inhibitor PAI-1 or the MMP-inhibitor TIMP-1. TAB elevated LV pressure comparably in all genotypes. In WT and t-PA−/− mice, cardiomyocyte hypertrophy was associated with myocardial fibrosis, LV dilatation and dysfunction, and pump failure after 7 weeks. In contrast, in u-PA−/− mice or in WT mice after PAI-1- and TIMP-1-gene transfer, cardiomyocyte hypertrophy was moderate and only minimally associated with cardiac fibrosis and LV dilatation, resulting in better preservation of pump function. Deficiency of MMP-9 had an intermediate effect. These findings suggest that the use of u-PA- or MMP-inhibitors might preserve cardiac pump function in LV pressure overloading. PMID:15631996

Speckle tracking echocardiography to assess regional ventricular function in patients with apical hypertrophic cardiomyopathy.

PubMed

Saccheri, María Cristina; Cianciulli, Tomás Francisco; Morita, Luis Alberto; Méndez, Ricardo José; Beck, Martín Alejandro; Guerra, Juan Enrique; Cozzarin, Alberto; Puente, Luciana Jimena; Balletti, Lorena Romina; Lax, Jorge Alberto

2017-04-26

To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy (HCM). We prospectively assessed 20 patients (mean age 53 ± 16 years, range: 18-81 years, 10 were male), with apical HCM. We measured global longitudinal peak systolic strain (GLPSS) in the midwall and endocardium of the left ventricle. The diastolic thickness of the 4 apical segments was 16.25 ± 2.75 mm. All patients had a normal global systolic function with a fractional shortening of 50% ± 8%. In spite of supernormal left ventricular (LV) systolic function, midwall GLPSS was decreased in all patients, more in the apical (-7.3% ± -8.8%) than in basal segments (-15.5% ± -6.93%), while endocardial GLPPS was significantly greater and reached normal values (apical: -22.8% ± -7.8%, basal: -17.9% ± -7.5%). This study shows that two-dimensional strain was decreased mainly confined to the mesocardium, while endocardium myocardial deformation was preserved in HCM and allowed to identify subclinical LV dysfunction. This transmural heterogeneity in systolic strain had not been previously described in HCM and could be explained by the distribution of myofibrillar disarray in deep myocardial areas. The clinical application of this novel finding may help further understanding of the pathophysiology of HCM.

Systolic and Diastolic Left Ventricular Mechanics during and after Resistance Exercise.

PubMed

Stöhr, Eric J; Stembridge, Mike; Shave, Rob; Samuel, T Jake; Stone, Keeron; Esformes, Joseph I

2017-10-01

To improve the current understanding of the impact of resistance exercise on the heart, by examining the acute responses of left ventricular (LV) strain, twist, and untwisting rate ("LV mechanics"). LV echocardiographic images were recorded in systole and diastole before, during and immediately after (7-12 s) double-leg press exercise at two intensities (30% and 60% of maximum strength, one-repetition maximum). Speckle tracking analysis generated LV strain, twist, and untwisting rate data. Additionally, beat-by-beat blood pressure was recorded and systemic vascular resistance (SVR) and LV wall stress were calculated. Responses in both exercise trials were statistically similar (P > 0.05). During effort, stroke volume decreased, whereas SVR and LV wall stress increased (P < 0.05). Immediately after effort, stroke volume returned to baseline, whereas SVR and wall stress decreased (P < 0.05). Similarly, acute exercise was accompanied by a significant decrease in systolic parameters of LV muscle mechanics (P < 0.05). However, diastolic parameters, including LV untwisting rate, were statistically unaltered (P > 0.05). Immediately after exercise, systolic LV mechanics returned to baseline levels (P < 0.05) but LV untwisting rate increased significantly (P < 0.05). A single, acute bout of double-leg press resistance exercise transiently reduces systolic LV mechanics, but increases diastolic mechanics after exercise, suggesting that resistance exercise has a differential impact on systolic and diastolic heart muscle function. The findings may explain why acute resistance exercise has been associated with reduced stroke volume but chronic exercise training may result in increased LV volumes.

A three-dimensional model-based partial volume correction strategy for gated cardiac mouse PET imaging

NASA Astrophysics Data System (ADS)

Dumouchel, Tyler; Thorn, Stephanie; Kordos, Myra; DaSilva, Jean; Beanlands, Rob S. B.; deKemp, Robert A.

2012-07-01

Quantification in cardiac mouse positron emission tomography (PET) imaging is limited by the imaging spatial resolution. Spillover of left ventricle (LV) myocardial activity into adjacent organs results in partial volume (PV) losses leading to underestimation of myocardial activity. A PV correction method was developed to restore accuracy of the activity distribution for FDG mouse imaging. The PV correction model was based on convolving an LV image estimate with a 3D point spread function. The LV model was described regionally by a five-parameter profile including myocardial, background and blood activities which were separated into three compartments by the endocardial radius and myocardium wall thickness. The PV correction was tested with digital simulations and a physical 3D mouse LV phantom. In vivo cardiac FDG mouse PET imaging was also performed. Following imaging, the mice were sacrificed and the tracer biodistribution in the LV and liver tissue was measured using a gamma-counter. The PV correction algorithm improved recovery from 50% to within 5% of the truth for the simulated and measured phantom data and image uniformity by 5-13%. The PV correction algorithm improved the mean myocardial LV recovery from 0.56 (0.54) to 1.13 (1.10) without (with) scatter and attenuation corrections. The mean image uniformity was improved from 26% (26%) to 17% (16%) without (with) scatter and attenuation corrections applied. Scatter and attenuation corrections were not observed to significantly impact PV-corrected myocardial recovery or image uniformity. Image-based PV correction algorithm can increase the accuracy of PET image activity and improve the uniformity of the activity distribution in normal mice. The algorithm may be applied using different tracers, in transgenic models that affect myocardial uptake, or in different species provided there is sufficient image quality and similar contrast between the myocardium and surrounding structures.

Favourable effects of exercise training on N-terminal pro-brain natriuretic peptide plasma levels in elderly patients after acute myocardial infarction.

PubMed

Giallauria, Francesco; Lucci, Rosa; De Lorenzo, Anna; D'Agostino, Mariantonietta; Del Forno, Domenico; Vigorito, Carlo

2006-11-01

regional or global impairment of left ventricular (LV) systolic or diastolic function leading to increased LV wall stress results in increased circulating levels of N-terminal pro-brain natriuretic peptide (NT-pro-BNP). this study aims at evaluating the effect of exercise training (ET) on NT-pro-BNP plasma levels in older patients recovering from acute myocardial infarction (AMI). prospective randomised study. Academic Medical Centre. forty older patients (33 males and 7 females) who experienced AMI. patients were randomised into two groups, each composed of 20 patients: Group A were enrolled in a 3-month exercise-based cardiac rehabilitation (CR) programme and Group B were discharged home with generic instructions to continue physical activity. NT-pro-BNP, cardiopulmonary and Doppler-echocardiographic parameters were measured at baseline and at 3-month follow-up. in Group A, ET reduced NT-pro-BNP levels (from 1446 +/- 475 to 435 +/- 251 pg/ml, P<0.001) and increased maximal exercise parameters; there was also an inverse correlation between changes in NT-pro-BNP levels and in VO(2peak) (r = -0.67, P<0.01), E-wave (r = -0.42, P<0.01) and E/A ratio (r = -0.60, P<0.01). In Group B, after 3 months, no changes were observed in NT-pro-BNP levels, exercise and echocardiographic parameters. LV volumes and left ventricular ejection fraction (LVEF) were unchanged after 3 months in both groups. three months ET in older patients after AMI was associated with a reduction in NT-pro-BNP levels and an overall improvement of exercise capacity, without negative LV remodelling and with improvement in early LV filling. Further investigation is required to evaluate whether in these patients the reduction of NT-pro-BNP levels at 3 months could be useful as a surrogate marker of favourable LV remodelling at a later follow-up.

The efficacy and tolerability of azilsartan in obese insulin-resistant mice with left ventricular pressure overload.

PubMed

Tarikuz Zaman, A K M; McLean, Danielle L; Sobel, Burton E

2013-10-01

Angiotensin II receptor blockers (ARBs) are used widely for the treatment of heart failure. However, their use in obese and insulin-resistant patients remains controversial. To clarify their potential efficacy in these conditions, we administered azilsartan medoxomil (azilsartan), a prodrug of an angiotensin II receptor blocker to mice fed a high-fat diet (HFD) with left ventricular (LV) pressure overload (aortic banding). LV fibrosis (hydroxyproline), cardiac plasminogen activator inhibitor-1 (PAI-1; a marker of profibrosis), and creatine kinase (a marker of myocardial viability and energetics) were assessed. LV wall thickness and cardiac function were assessed echocardiographically. Mice given a HFD were obese and insulin resistant. Their LV hypertrophy was accompanied by greater LV PAI-1 and reduced LV creatine kinase compared with normal diet controls. Drug treatment reduced LV wall thickness, hypertrophy, and PAI-1 and increased cardiac output after aortic banding compared with results in HFD vehicle controls. Thus, azilsartan exerted favorable biological effects on the hearts of obese insulin-resistant mice subjected to LV pressure overload consistent with its potential utility in patients with analogous conditions.

New-Onset Heart Failure and Mortality in Hospital Survivors of Sepsis-Related Left Ventricular Dysfunction.

PubMed

Vallabhajosyula, Saraschandra; Jentzer, Jacob C; Geske, Jeffrey B; Kumar, Mukesh; Sakhuja, Ankit; Singhal, Akhil; Poterucha, Joseph T; Kashani, Kianoush; Murphy, Joseph G; Gajic, Ognjen; Kashyap, Rahul

2018-02-01

The association between new-onset left ventricular (LV) dysfunction during sepsis with long-term heart failure outcomes is lesser understood. Retrospective cohort study of all adult patients with severe sepsis and septic shock between 2007 and 2014 who underwent echocardiography within 72 h of admission to the intensive care unit. Patients with prior heart failure, LV dysfunction, and structural heart disease were excluded. LV systolic dysfunction was defined as LV ejection fraction <50% and LV diastolic dysfunction as ≥grade II. Primary composite outcome included new hospitalization for acute decompensated heart failure and all-cause mortality at 2-year follow-up. Secondary outcomes included persistent LV dysfunction, and hospital mortality and length of stay. During this 8-year period, 434 patients with 206 (48%) patients having LV dysfunction were included. The two groups had similar baseline characteristics, but those with LV dysfunction had worse function as demonstrated by worse LV ejection fraction, cardiac index, and LV diastolic dysfunction. In the 331 hospital survivors, new-onset acute decompensated heart failure hospitalization did not differ between the two cohorts (15% vs. 11%). The primary composite outcome was comparable at 2-year follow-up between the groups with and without LV dysfunction (P = 0.24). Persistent LV dysfunction was noted in 28% hospital survivors on follow-up echocardiography. Other secondary outcomes were similar between the two groups. In patients with severe sepsis and septic shock, the presence of new-onset LV dysfunction did not increase the risk of long-term adverse heart failure outcomes.

An integrated platform for image-guided cardiac resynchronization therapy

NASA Astrophysics Data System (ADS)

Ma, Ying Liang; Shetty, Anoop K.; Duckett, Simon; Etyngier, Patrick; Gijsbers, Geert; Bullens, Roland; Schaeffter, Tobias; Razavi, Reza; Rinaldi, Christopher A.; Rhode, Kawal S.

2012-05-01

Cardiac resynchronization therapy (CRT) is an effective procedure for patients with heart failure but 30% of patients do not respond. This may be due to sub-optimal placement of the left ventricular (LV) lead. It is hypothesized that the use of cardiac anatomy, myocardial scar distribution and dyssynchrony information, derived from cardiac magnetic resonance imaging (MRI), may improve outcome by guiding the physician for optimal LV lead positioning. Whole heart MR data can be processed to yield detailed anatomical models including the coronary veins. Cine MR data can be used to measure the motion of the LV to determine which regions are late-activating. Finally, delayed Gadolinium enhancement imaging can be used to detect regions of scarring. This paper presents a complete platform for the guidance of CRT using pre-procedural MR data combined with live x-ray fluoroscopy. The platform was used for 21 patients undergoing CRT in a standard catheterization laboratory. The patients underwent cardiac MRI prior to their procedure. For each patient, a MRI-derived cardiac model, showing the LV lead targets, was registered to x-ray fluoroscopy using multiple views of a catheter looped in the right atrium. Registration was maintained throughout the procedure by a combination of C-arm/x-ray table tracking and respiratory motion compensation. Validation of the registration between the three-dimensional (3D) roadmap and the 2D x-ray images was performed using balloon occlusion coronary venograms. A 2D registration error of 1.2 ± 0.7 mm was achieved. In addition, a novel navigation technique was developed, called Cardiac Unfold, where an entire cardiac chamber is unfolded from 3D to 2D along with all relevant anatomical and functional information and coupled to real-time device detection. This allowed more intuitive navigation as the entire 3D scene was displayed simultaneously on a 2D plot. The accuracy of the unfold navigation was assessed off-line using 13 patient data sets by computing the registration error of the LV pacing lead electrodes which was found to be 2.2 ± 0.9 mm. Furthermore, the use of Unfold Navigation was demonstrated in real-time for four clinical cases.

Renal sympathetic denervation inhibits the development of left ventricular mechanical dyssynchrony during the progression of heart failure in dogs.

PubMed

Hu, Wei; Zhao, Qing-yan; Yu, Sheng-bo; Sun, Bin; Chen, Liao; Cao, Sheng; Guo, Rui-qiang

2014-11-22

The purpose of this study was to investigate whether transcatheter renal sympathetic denervation (RSD) interfere with the development of left ventricular (LV) mechanical dyssynchrony during the progression of heart failure (HF). Nineteen beagles were randomly divided into sham-operated group (six dogs), control group (seven dogs), and RSD group (six dogs). Sham-operated group were implanted with pacemakers without pacing; Control group were implanted with pacemakers and underwent 3 weeks of rapid right ventricular pacing; and RSD group underwent catheter-based RSD bilaterally and were simultaneously implanted with pacemakers. Both LV strain and LV dyssynchrony were analyzed via 2D speckle-tracking strain echocardiography to evaluate LV function. Longitudinal dyssynchrony was determined as the standard deviation for time-to-peak speckle-tracking strain on apical 4- and 2-chamber views. Radial and circumferential dyssynchrony was determined as the standard deviation for time-to-peak speckle-tracking strain in mid- and base-LV short-axis views. Each myocardial function was also evaluated by averaging the peak systolic strains. LV systolic pressure (LVSP) and LV end-diastolic pressure (LVEDP) were measured. The LV interstitial fibrosis was determined by histological analysis. Plasma angiotensin II (Ang II), aldosterone and norepinephrine (NE) levels were also measured. After 3 weeks, all of the dogs in both the control and RSD groups showed greater LV end-diastolic volume compared with the sham-operated group; however, the dogs in the RSD group had a higher LV ejection fraction (LVEF) than the dogs in the control group (p<0.001). The LV systolic strains were higher in the RSD group than in the control group (p<0.001 for longitudinal, circumferential and radial strain, respectively). The levels of LV dyssynchrony were lower in the RSD group than in the control group (p<0.001 for longitudinal, circumferential and radial dyssynchrony, respectively). Compared with dogs with control alone, RSD dogs had lower LV end-diastolic pressures and less fibrous tissue. The levels of plasma Ang II, aldosterone and NE were lower in the RSD group than in the control group. RSD inhibites the development of left ventricular mechanical dyssynchrony during the progression of heart failure in dogs.

Diabetes as an independent predictor of left ventricular longitudinal strain reduction at rest and during dobutamine stress test in patients with significant coronary artery disease.

PubMed

Wierzbowska-Drabik, Karina; Trzos, Ewa; Kurpesa, Malgorzata; Rechcinski, Tomasz; Miskowiec, Dawid; Cieslik-Guerra, Urszula; Uznanska-Loch, Barbara; Sobczak, Maria; Kasprzak, Jaroslaw Damian

2017-12-09

Diabetes (DM) is a strong cardiovascular risk factor modifying also the left ventricular (LV) function that may be objectively assessed with echocardiographic strain analysis. Although the impact of isolated DM on myocardial deformation has been already studied, few data concern diabetics with coronary artery disease (CAD), especially in all stages of dobutamine stress echocardiography (DSE). We compared LV systolic function during DSE in CAD with and without DM using state-of-the art speckle-tracking quantification and assessed the impact of DM on LV systolic strain. DSE was performed in 250 patients with angina who afterwards had coronarography with ≥50% stenosis in the left main artery and ≥70% in other arteries considered as significant. In this analysis, we included 127 patients with confirmed CAD: 42 with DM [DM(+); mean age 64 ± 9 years] and 85 patients without DM [DM(-); mean age 63 ± 9 years]. The severity of CAD and LV ejection fraction (EF) were similar in both groups. Global and regional LV peak systolic longitudinal strain (PSLS) revealed in all DSE phases lower values in DM(+) group: 14.5 ± 3.6% vs. 17.4 ± 4.0% at rest; P = 0.0001, 13.8 ± 3.9% vs. 16.7 ± 4.0% at peak stress; P = 0.0002, and 14.2 ± 3.1% vs. 15.5 ± 3.5% at recovery; P = 0.0432 for global parameters, although dobutamine challenge did not enhance further resting differences. LV EF, body surface area, and diabetes were independent predictors for strain in 16-variable model (R2 = 0, 51, P < 0.001). PSLS although diminished in both groups with CAD was lower in diabetics at all DSE stages, and DM was an independent predictor of this impairment. However, the dobutamine challenge did not deepen the resting differences, suggesting that the direct impact of coronary stenoses effaces the influence of DM during DSE. The comparison with our previous data revealed synergistic, detrimental effect of coexisting CAD and DM on myocardial strain. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Cardiovascular Effects of 1 Year of Alagebrium and Endurance Exercise Training in Healthy Older Individuals

PubMed Central

Fujimoto, Naoki; Hastings, Jeffrey L.; Carrick-Ranson, Graeme; Shafer, Keri M.; Shibata, Shigeki; Bhella, Paul S.; Abdullah, Shuaib M.; Barkley, Kyler W.; Adams-Huet, Beverley; Boyd, Kara N.; Livingston, Sheryl A.; Palmer, Dean; Levine, Benjamin D.

2014-01-01

Background Lifelong exercise training maintains a youthful compliance of the left ventricle (LV), whereas a year of exercise training started later in life fails to reverse LV stiffening, possibly because of accumulation of irreversible advanced glycation end products. Alagebrium breaks advanced glycation end product crosslinks and improves LV stiffness in aged animals. However, it is unclear whether a strategy of exercise combined with alagebrium would improve LV stiffness in sedentary older humans. Methods and Results Sixty-two healthy subjects were randomized into 4 groups: sedentary+placebo; sedentary+alagebrium (200 mg/d); exercise+placebo; and exercise+alagebrium. Subjects underwent right heart catheterization to define LV pressure–volume curves; secondary functional outcomes included cardiopulmonary exercise testing and arterial compliance. A total of 57 of 62 subjects (67±6 years; 37 f/20 m) completed 1 year of intervention followed by repeat measurements. Pulmonary capillary wedge pressure and LV end-diastolic volume were measured at baseline, during decreased and increased cardiac filling. LV stiffness was assessed by the slope of LV pressure–volume curve. After intervention, LV mass and end-diastolic volume increased and exercise capacity improved (by ≈8%) only in the exercise groups. Neither LV mass nor exercise capacity was affected by alagebrium. Exercise training had little impact on LV stiffness (training×time effect, P=0.46), whereas alagebrium showed a modest improvement in LV stiffness compared with placebo (medication×time effect, P=0.04). Conclusions Alagebrium had no effect on hemodynamics, LV geometry, or exercise capacity in healthy, previously sedentary seniors. However, it did show a modestly favorable effect on age-associated LV stiffening. PMID:24130005

Race-related differences in left ventricular structural and functional remodeling in response to increased afterload: the Atherosclerosis Risk in Communities Study

PubMed Central

Fernandes-Silva, Miguel M; Shah, Amil M; Hegde, Sheila; Goncalves, Alexandra; Claggett, Brian; Cheng, Susan; Nadruz, Wilson; Kitzman, Dalane W.; Konety, Suma H.; Matsushita, Kunihiro; Mosley, Thomas; Lam, Carolyn S.P.; Borlaug, Barry A.; Solomon, Scott D

2016-01-01

Background Chronic increasing in arterial afterload may be an important trigger for left ventricular (LV) remodeling and dysfunction that lead to heart failure (HF). Racial differences in the predisposition to HF are well described, but the underlying mechanisms remain unclear. Objective We evaluated the racial differences in arterial elastance (Ea), which reflects the arterial afterload faced by the LV, and its associations with cardiac structure and function. We hypothesize that the LV in blacks displays heightened afterload sensitivity as compared to whites. Methods We studied 5727 community-based, elderly Atherosclerosis Risk in Community (ARIC) Study participants (22% black), who underwent echocardiography between 2011 and 2013. Results Blacks were younger (75 ± 5 vs 76 ± 5 years old), more frequently women (66 vs 57%), and had higher prevalence of obesity (46 vs 31%), hypertension (94 vs 80%), and diabetes mellitus (47 vs 34%) than whites. Adjusting for these baseline differences, Ea was higher among blacks (1.96 ± 0.01 vs 1.80 ± 0.01 mmHg/mL). In blacks, Ea was associated with greater LV remodeling (LV mass index, β = 3.21 ± 0.55 g/m2, p<0.001) and higher LV filling pressures (E/e′ ratio, β = 0.42 ± 0.11, p<0.001). These relationships were not observed in whites (LV mass, β = 0.16 ± 0.32 g/m2, p=0.61, p for interaction <0.001; E/e′ratio, β = −0.32 ± 0.06, p<0.001, p for interaction <0.001).. Conclusion These community-based data suggest that black Americans display heightened afterload sensitivity as a stimulus for LV structural and functional remodeling, which may contribute to their greater risk of HF, as compared to white Americans. PMID:28017356

Gestational changes in left ventricular myocardial contractile function: new insights from two-dimensional speckle tracking echocardiography.

PubMed

Sengupta, Shantanu P; Bansal, Manish; Hofstra, Leonard; Sengupta, Partho P; Narula, Jagat

2017-01-01

The goal of this study was to evaluate the impact of pregnancy and labor on left ventricular (LV) myocardial mechanics using speckle tracking echocardiography (STE). Pregnancy is characterized by profound hormonal and hemodynamic alterations that directly or indirectly influence cardiac structure and function. However, the impact of these changes on left ventricular (LV) myocardial contractile function has not been fully elucidated. In this prospective, longitudinal study, 35 pregnant women underwent serial clinical and echocardiographic evaluation during each trimester and at labor. Two dimensional STE was performed to measure global LV longitudinal, circumferential and radial strain (GLS, GCS and GRS, respectively). Similar data obtained from 20 nulliparous, age-matched women were used as control. All strain values during pregnancy were adjusted for age and hemodynamic parameters. There was a progressive increase in heart rate, systolic and diastolic blood pressure, cardiac output and LV stroke-work during pregnancy. LV end-diastolic and end-systolic volumes also increased progressively but LV ejection fraction remained unaltered, except for slight reduction during the second trimester. Compared to the controls, GLS and GCS were reduced in the first trimester itself (GLS -22.39 ± 5.43 % vs. -18.66 ± 0.64 %, P 0.0002; GCS -20.84 ± 3.20 vs. -17.88 ± 0.09, P < 0.001) and remained so throughout the pregnancy and labor. In contrast, GRS showed an increase during pregnancy which peaked during the second trimester (24.18 ± 0.39 % vs. 18.06 ± 8.14 % in controls, P < 0.001). Alterations in loading conditions during pregnancy are associated with counterbalancing changes in the myocardial mechanics. LV longitudinal and circumferential strain are reduced whereas radial strain is increased. These counterbalancing changes serve to maintain overall LV ejection performance within a normal range and enable the maternal heart to meet the hemodynamic demands of pregnancy and labor.

Cytoskeletal role in the transition from compensated to decompensated hypertrophy during adult canine left ventricular pressure overloading

NASA Technical Reports Server (NTRS)

Tagawa, H.; Koide, M.; Sato, H.; Zile, M. R.; Carabello, B. A.; Cooper, G. 4th

1998-01-01

Increased microtubule density causes cardiocyte contractile dysfunction in right ventricular (RV) pressure-overload hypertrophy, and these linked phenotypic and contractile abnormalities persist and progress during the transition to failure. Although more severe in cells from failing than hypertrophied RVs, the mechanical defects are normalized in each case by microtubule depolymerization. To define the role of increased microtubule density in left ventricular (LV) pressure-overload hypertrophy and failure, in a given LV we examined ventricular mechanics, sarcomere mechanics, and free tubulin and microtubule levels in control dogs and in dogs with aortic stenosis both with LV hypertrophy alone and with initially compensated hypertrophy that had progressed to LV muscle failure. In comparing initial values with those at study 8 weeks later, dogs with hypertrophy alone had a very substantial increase in LV mass but preservation of a normal ejection fraction and mean systolic wall stress. Dogs with hypertrophy and associated failure had a substantial but lesser increase in LV mass and a reduction in ejection fraction, as well as a marked increase in mean systolic wall stress. Cardiocyte contractile function was equivalent, and unaffected by microtubule depolymerization, in cells from control LVs and those with compensated hypertrophy. In contrast, cardiocyte contractile function in cells from failing LVs was quite depressed but was normalized by microtubule depolymerization. Microtubules were increased only in failing LVs. These contractile and cytoskeletal changes, when assayed longitudinally in a given dog by biopsy, appeared in failing ventricles only when wall stress began to increase and function began to decrease. Thus, the microtubule-based cardiocyte contractile dysfunction characteristic of pressure-hypertrophied myocardium, originally described in the RV, obtains equally in the LV but is shown here to have a specific association with increased wall stress.

New concept of the contraction-extension property of the left ventricular myocardium.

PubMed

Tanaka, Motonao; Sakamoto, Tsuguya; Sugawara, Shigeo; Katahira, Yoshiaki; Tabuchi, Haruna; Nakajima, Hiroyuki; Kurokawa, Takafumi; Kanai, Hiroshi; Hasegawa, Hideyuki; Ohtsuki, Shigeo

2014-04-01

Using newly developed ultrasonic technology, we attempted to disclose the characteristics of the left ventricular (LV) contraction-extension (C-E) property, which has an important relationship to LV function. Strain rate (SR) distribution within the posterior wall and interventricular septum was microscopically measured with a high accuracy of 821μm in spatial resolution by using the phase difference tracking method. The subjects were 10 healthy men (aged 30-50 years). The time course of the SR distribution disclosed the characteristic C-E property, i.e. the contraction started from the apex and propagated toward the base on one hand, and from the epicardial side toward the endocardial side on the other hand. Therefore, the contraction of one area and the extension of another area simultaneously appeared through nearly the whole cardiac cycle, with the contracting part positively extending the latter part and vice versa. The time course of these propagations gave rise to the peristalsis and the bellows action of the LV wall, and both contributed to effective LV function. The LV contraction started coinciding in time with the P wave of the electrocardiogram, and the cardiac cycle was composed of 4 phases, including 2 types of transitional phase, as well as the ejection phase and slow filling phase. The sum of the measurement time duration of either the contraction or the extension process occupied nearly equal duration in normal conditions. The newly developed ultrasonic technology revealed that the SR distribution was important in evaluating the C-E property of the LV myocardium. The harmonious succession of the 4 cardiac phases newly identified seemed to be helpful in understanding the mechanism to keep long-lasting pump function of the LV. Copyright © 2013 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Lower risk of postinfarct rupture in mouse heart overexpressing beta 2-adrenergic receptors: importance of collagen content.

PubMed

Gao, Xiao-Ming; Dilley, Rodney J; Samuel, Chrishan S; Percy, Elodie; Fullerton, Meryl J; Dart, Anthony M; Du, Xiao-Jun

2002-10-01

This paper addresses whether the enhanced left ventricular (LV) contractility and heart rate, seen in transgenic mice overexpressing beta -adrenergic receptor in the heart, might raise the incidence of LV rupture after myocardial infarct. Transgenic and wild-type mice underwent left coronary artery occlusion. Postinfarct deaths that occurred 1-7 days after surgery were analyzed. Hemodynamics, morphologic parameters, and collagen content in the LV were determined. A significantly lower incidence of LV rupture was observed in transgenic than in wild-type mice 3-5 days after myocardial infarct (2.5 versus 19.7%, p < 0.05), despite a similar infarct size between the two groups and better hemodynamic function in transgenic mouse hearts. Morphologic analysis showed a more severe infarct expansion in wild-type versus transgenic mice or in mice dying of rupture versus those that died of acute heart failure. Collagen content was higher in the LV of sham-operated transgenic than wild-type mice (p < 0.01) with both type I and type III collagen elevated. Such difference in collagen content between transgenic and wild-type mice was maintained in noninfarcted and infarcted LV. In conclusion, transgenic mice overexpressing beta -adrenergic receptor had a lower risk of cardiac rupture during the acute phase after infarction despite the markedly enhanced LV contractility and heart rate. As a hyperdynamic function due to beta-adrenergic activation would likely increase the risk of cardiac rupture and infarct expansion, the lack of rupture in this transgenic mouse model suggests that the interstitial collagen level is a more important factor than functional status in the pathogenesis of rupture and infarct expansion.

Role of the His-Cys finger of Moloney murine leukemia virus integrase protein in integration and disintegration.

PubMed Central

Jonsson, C B; Roth, M J

1993-01-01

Retroviral integrases mediate site-specific endonuclease and transesterification reactions in the absence of exogenous energy. The basis for the sequence specificity in these integrase-viral DNA recognition processes is unknown. Structural analogs of the disintegration substrate were made to analyze the disintegration reaction mechanism for the Moloney murine leukemia virus (M-MuLV) integrase (IN). Modifications in the target DNA portion of the disintegration substrate decreased enzymatic activity, while substitution of the highly conserved CA in the viral long terminal repeat portion had no effect on activity. The role of the His-Cys finger region in catalysis was addressed by N-ethylmaleimide (NEM) modification of the cysteine residues of M-MuLV IN as well as by mutations. Both integration activities, 3' processing, and strand transfer, were completely inhibited by NEM modification of M-MuLV IN, while disintegration activity was only partially sensitive. However, structural analogs of the disintegration substrates that were modified in the target DNA and had the conserved CA removed were not active with NEM-treated M-MuLV IN. In addition, mutants made in the His-Cys region of M-MuLV IN were examined and found to also be completely blocked in integration but not disintegration activity. These data suggest that the domains of M-MuLV IN that are required for the forward integration reaction substrate differ from those required for the reverse disintegration reaction substrate. Images PMID:8350412

Repeated doses of cardiac mesenchymal cells are therapeutically superior to a single dose in mice with old myocardial infarction.

PubMed

Guo, Yiru; Wysoczynski, Marcin; Nong, Yibing; Tomlin, Alex; Zhu, Xiaoping; Gumpert, Anna M; Nasr, Marjan; Muthusamy, Senthikumar; Li, Hong; Book, Michael; Khan, Abdur; Hong, Kyung U; Li, Qianhong; Bolli, Roberto

2017-03-01

We have recently demonstrated that repeated administrations of c-kit POS cardiac progenitor cells (CPCs) have cumulative beneficial effects in rats with old myocardial infarction (MI), resulting in markedly greater improvement in left ventricular (LV) function compared with a single administration. To determine whether this paradigm applies to other species and cell types, mice with a 3-week-old MI received one or three doses of cardiac mesenchymal cells (CMCs), a novel cell type that we have recently described. CMCs or vehicle were infused percutaneously into the LV cavity, 14 days apart. Compared with vehicle-treated mice, the single-dose group exhibited improved LV ejection fraction (EF) after the 1st infusion (consisting of CMCs) but not after the 2nd and 3rd (vehicle). In contrast, in the multiple-dose group, LV EF improved after each CMC infusion, so that at the end of the study, LV EF averaged 35.5 ± 0.7% vs. 32.7 ± 0.6% in the single-dose group (P < 0.05). The multiple-dose group also exhibited less collagen in the non-infarcted region vs. the single-dose group. Engraftment and differentiation of CMCs were negligible in both groups, indicating paracrine effects. These results demonstrate that, in mice with ischemic cardiomyopathy, the beneficial effects of three doses of CMCs are significantly greater than those of one dose, supporting the concept that multiple treatments are necessary to properly evaluate the full therapeutic potential of cell therapy. Thus, the repeated-treatment paradigm is not limited to c-kit POS CPCs or to rats, but applies to other cell types and species. The generalizability of this concept dramatically augments its significance.

Modern nuclear cardiac imaging in diagnosis and clinical management of patients with left ventricular dysfunction.

PubMed

Abidov, A; Hachamovitch, R; Berman, D S

2004-12-01

Congestive heart failure (CHF) has become a large social burden in modern Western society, with very high morbidity and mortality and extremely large financial costs. The largest cause of CHF is coronary heart disease, with ventricular dysfunction that may or may not be reversible by revascularization. Thus, evaluation of the viable myocardial tissue in patients with ischemic left ventricular (LV) dysfunction has important clinical and therapeutic implications. Furthermore, since patients with ventricular dysfunction are at higher operative risk, cardiologists and cardiac surgeons are commonly faced with issues regarding the balance between the potential risk vs benefit of revascularization procedures. Cardiac nuclear imaging [myocardial perfusion SPECT (MPS) and positron emission tomography (PET)] provide objective information that augments standard clinical and angiographic assessments of patients with ventricular dysfunction with respect to diagnosis (etiology), prognosis, and potential benefit from intervention. Development of the technology and methodology of gated MPS, now the routine method for MPS, allows assessment of the extent and severity of inducible ischemia as well as hypoperfused but viable myocardium, and also provides measurements of LV ejection fraction, regional wall motion, LV volume measurements, diastolic function and LV geometry. With PET, myocardial metabolism and blood flow reserve can be added to the measurements provided by nuclear cardiology procedures. This paper provides insight into the current evidence regarding settings in which nuclear cardiac imaging procedures are helpful in assessment of patients in the setting of coronary artery disease with severe LV dysfunction. A risk-benefit approach to MPS results is proposed, with principal focus on identifying patients at risk for major cardiac events who may benefit from myocardial revascularization.

Association of N-Terminal Pro-B-Type Natriuretic Peptide with Left Ventricular Structure and Function in Chronic Kidney Disease (From the Chronic Renal Insufficiency Cohort [CRIC])

PubMed Central

Mishra, Rakesh K.; Li, Yongmei; Ricardo, Ana C.; Yang, Wei; Keane, Martin; Cuevas, Magdalena; Christenson, Robert; DeFilippi, Christopher; Chen, Jing; He, Jiang; Kallem, Radhakrishna R.; Raj, Dominic S.; Schelling, Jeffrey R.; Wright, Jackson; Go, Alan S.; Shlipak, Michael G.

2017-01-01

We evaluated the cross-sectional associations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) with cardiac structural and functional abnormalities in a cohort of chronic kidney disease (CKD) patients without clinical heart failure (HF), the Chronic Renal Insufficiency Cohort (n=3,232). Associations of NT-proBNP with echocardiographically determined left ventricular (LV) mass and LV systolic and diastolic function were evaluated by multivariable logistic and linear regression models. Reclassification of participants’ predicted risk of LV hypertrophy (LVH), systolic and diastolic dysfunction was performed using a category-free net reclassification improvement (NRI) index that compared a clinical model with and without NT-proBNP. The median (interquartile range) NT-proBNP was 126.6 pg/ml (55.5–303.7). The highest quartile of NT-proBNP was associated with nearly three-fold odds of LVH (odds ratio (OR) 2.7, 95% confidence interval (CI) 1.8–4.0) and LV systolic dysfunction (2.7, 1.7–4.5) and two-fold odds of diastolic dysfunction (2.0, 1.3–2.9) in the fully adjusted models. When evaluated alone as a screening test, NT-proBNP functioned modestly for the detection of LVH (area under the curve, AUC 0.66) and LV systolic dysfunction (AUC 0.62), and poorly for the detection of diastolic dysfunction (AUC 0.51). However, when added to the clinical model, NT-proBNP significantly reclassified participants’ likelihood of having LVH (NRI 0.14, 95% CI 0.13–0.15; p<0.001) and LV systolic dysfunction (0.28, 0.27–0.30; p<0.001), but not diastolic dysfunction (0.10, 0.10–0.11; p=0.07). In conclusion, in this large CKD cohort without HF, NT-proBNP had strong associations with prevalent LVH and LV systolic dysfunction. PMID:23178053

Mediterranean diet score and left ventricular structure and function: the Multi-Ethnic Study of Atherosclerosis12

PubMed Central

Levitan, Emily B; Ahmed, Ali; Arnett, Donna K; Polak, Joseph F; Hundley, W Gregory; Bluemke, David A; Heckbert, Susan R; Jacobs, David R; Nettleton, Jennifer A

2016-01-01

Background: Data are limited on the relation between dietary patterns and left ventricular (LV) structure and function. Objective: We examined cross-sectional associations of a diet-score assessment of a Mediterranean dietary pattern with LV mass, volume, mass-to-volume ratio, stroke volume, and ejection fraction. Design: We measured LV variables with the use of cardiac MRI in 4497 participants in the Multi-Ethnic Study of Atherosclerosis study who were aged 45–84 y and without clinical cardiovascular disease. We calculated a Mediterranean diet score from intakes of fruit, vegetables, nuts, legumes, whole grains, fish, red meat, the monounsaturated fat:saturated fat ratio, and alcohol that were self-reported with the use of a food-frequency questionnaire. We used linear regression with adjustment for body size, physical activity, and cardiovascular disease risk factors to model associations and assess the shape of these associations (linear or quadratic). Results: The Mediterranean diet score had a slight U-shaped association with LV mass (adjusted means: 146, 145, 146, and 147 g across quartiles of diet score, respectively; P-quadratic trend = 0.04). The score was linearly associated with LV volume, stroke volume, and ejection fraction: for each +1-U difference in score, LV volume was 0.4 mL higher (95% CI: 0.0, 0.8 mL higher), the stroke volume was 0.5 mL higher (95% CI: 0.2, 0.8 mL higher), and the ejection fraction was 0.2 percentage points higher (95% CI: 0.1, 0.3 percentage points higher). The score was not associated with the mass-to-volume ratio. Conclusions: A higher Mediterranean diet score is cross-sectionally associated with a higher LV mass, which is balanced by a higher LV volume as well as a higher ejection fraction and stroke volume. Participants in this healthy, multiethnic sample whose dietary patterns most closely conformed to a Mediterranean-type pattern had a modestly better LV structure and function than did participants with less–Mediterranean-like dietary patterns. This trial was registered at clinicaltrials.gov as NCT00005487. PMID:27488238

Mediterranean diet score and left ventricular structure and function: the Multi-Ethnic Study of Atherosclerosis.

PubMed

Levitan, Emily B; Ahmed, Ali; Arnett, Donna K; Polak, Joseph F; Hundley, W Gregory; Bluemke, David A; Heckbert, Susan R; Jacobs, David R; Nettleton, Jennifer A

2016-09-01

Data are limited on the relation between dietary patterns and left ventricular (LV) structure and function. We examined cross-sectional associations of a diet-score assessment of a Mediterranean dietary pattern with LV mass, volume, mass-to-volume ratio, stroke volume, and ejection fraction. We measured LV variables with the use of cardiac MRI in 4497 participants in the Multi-Ethnic Study of Atherosclerosis study who were aged 45-84 y and without clinical cardiovascular disease. We calculated a Mediterranean diet score from intakes of fruit, vegetables, nuts, legumes, whole grains, fish, red meat, the monounsaturated fat:saturated fat ratio, and alcohol that were self-reported with the use of a food-frequency questionnaire. We used linear regression with adjustment for body size, physical activity, and cardiovascular disease risk factors to model associations and assess the shape of these associations (linear or quadratic). The Mediterranean diet score had a slight U-shaped association with LV mass (adjusted means: 146, 145, 146, and 147 g across quartiles of diet score, respectively; P-quadratic trend = 0.04). The score was linearly associated with LV volume, stroke volume, and ejection fraction: for each +1-U difference in score, LV volume was 0.4 mL higher (95% CI: 0.0, 0.8 mL higher), the stroke volume was 0.5 mL higher (95% CI: 0.2, 0.8 mL higher), and the ejection fraction was 0.2 percentage points higher (95% CI: 0.1, 0.3 percentage points higher). The score was not associated with the mass-to-volume ratio. A higher Mediterranean diet score is cross-sectionally associated with a higher LV mass, which is balanced by a higher LV volume as well as a higher ejection fraction and stroke volume. Participants in this healthy, multiethnic sample whose dietary patterns most closely conformed to a Mediterranean-type pattern had a modestly better LV structure and function than did participants with less-Mediterranean-like dietary patterns. This trial was registered at clinicaltrials.gov as NCT00005487. © 2016 American Society for Nutrition.

Relationship between early diastolic intraventricular pressure gradients, an index of elastic recoil, and improvements in systolic and diastolic function.

PubMed

Firstenberg, M S; Smedira, N G; Greenberg, N L; Prior, D L; McCarthy, P M; Garcia, M J; Thomas, J D

2001-09-18

Early diastolic intraventricular pressure gradients (IVPGs) have been proposed to relate to left ventricular (LV) elastic recoil and early ventricular "suction." Animal studies have demonstrated relationships between IVPGs and systolic and diastolic indices during acute ischemia. However, data on the effects of improvements in LV function in humans and the relationship to IVPGs are lacking. Eight patients undergoing CABG and/or infarct exclusion surgery had a triple-sensor high-fidelity catheter placed across the mitral valve intraoperatively for simultaneous recording of left atrial (LA), basal LV, and apical LV pressures. Hemodynamic data obtained before bypass were compared with those with similar LA pressures and heart rates obtained after bypass. From each LV waveform, the time constant of LV relaxation (tau), +dP/dt(max), and -dP/dt(max) were determined. Transesophageal echocardiography was used to determined end-diastolic (EDV) and end-systolic (ESV) volumes and ejection fractions (EF). At similar LA pressures and heart rates, IVPG increased after bypass (before bypass 1.64+/-0.79 mm Hg; after bypass 2.67+/-1.25 mm Hg; P<0.01). Significant improvements were observed in ESV, as well as in apical and basal +dP/dt(max), -dP/dt(max), and tau (each P<0.05). Overall, IVPGs correlated inversely with both ESV (IVPG=-0.027[ESV]+3.46, r=-0.64) and EDV (IVPG=-0.027[EDV]+4.30, r=-0.70). Improvements in IVPGs correlated with improvements in apical tau (Deltatau =5.93[DeltaIVPG]+4.76, r=0.91) and basal tau (Deltatau =2.41[DeltaIVPG]+5.13, r=-0.67). Relative changes in IVPGs correlated with changes in ESV (DeltaESV=-0.97[%DeltaIVPG]+23.34, r=-0.79), EDV (DeltaEDV=-1.16[%DeltaIVPG]+34.92, r=-0.84), and EF (DeltaEF=0.38[%DeltaIVPG]-8.39, r=0.85). Improvements in LV function also increase IVPGs. These changes in IVPGs, suggestive of increases in LV suction and elastic recoil, correlate directly with improvements in LV relaxation and ESV.

CARDIAC STRUCTURAL AND FUNCTIONAL ABNORMALITIES IN FEMALES WITH UNTREATED HYPOPITUITARISM DUE TO SHEEHAN SYNDROME: RESPONSE TO HORMONE REPLACEMENT THERAPY.

PubMed

Laway, Bashir Ahmad; Ramzan, Mahroosa; Allai, Mohd Sultan; Wani, Arshad Iqbal; Misgar, Raiz Ahmad

2016-09-01

Data on cardiac abnormalities in females with untreated hypopituitarism are limited. We investigated echocardiographic abnormalities in females with untreated hypopituitarism and their response to treatment. Twenty-three females with treatment-naïve hypopituitarism and 30 matched healthy controls were evaluated for cardiac structure and function. Echocardiographic evaluation was done at presentation and after achieving a euthyroid and eucortisol state. Fourteen (61%) patients had mitral regurgitation, and 11 (48%) had pericardial effusion as against none among controls. Indices of left ventricular (LV) size like LV end diastolic dimension (LVEDD; 44.5 ± 3.5 mm in cases vs. 47.6 ± 3.8 mm in controls, P = .004), and LV diastolic volume (LVEDV; 91.8 ± 18.0 mL versus 106.5 ± 20.4 mL, P = .009) were significantly lower in the SS group compared with controls. LV mass (LVM) was 70.8 ± 19.2 g in cases and 108.0 ± 33.2 g in controls (P = .02). Similarly, indices of LV systolic function like stroke volume (SV; 59.1 ± 12.0 mL in cases and 74.4 ± 15.8 mL in controls; P = .000), ejection fraction (EF; 64.3 ± 6.2 % in cases against 69.9 ± 9.2 % in controls; P = .03), and fractional shortening (FS; 34.9 ± 4.7% versus 40.1 ± 4.4%, P = .000) were significantly decreased in patients compared with controls. Cardiac abnormalities normalized with restoration of a euthyroid and eucortisol state. Pericardial effusion, mitral regurgitation, and diminished LVM are common in females with untreated hypopituitarism. ACTH = adrenocorticotrophic hormone BMI = body mass index DT = deceleration time EDV = end-diastolic volume EF = ejection fraction FS = fractional shortening GH = growth hormone IGF-1 = insulin growth factor-1 ITT = insulin tolerance test IVSd = interventricular septal diameter LH = luteinizing hormone LV = left ventricular LVEDD = LV end diastolic dimension LVEDV = LV end diastolic volume LVM = LV mass MRI = magnetic resonance imaging MVP = mitral value prolapse PPH = postpartum hemorrhage PWd = posterior wall diameter SS = Sheehan syndrome SV = stroke volume T3 = triiodothyronine T4 = thyroxine TSH = thyroid-stimulating hormone.

Relationship between early diastolic intraventricular pressure gradients, an index of elastic recoil, and improvements in systolic and diastolic function

NASA Technical Reports Server (NTRS)

Firstenberg, M. S.; Smedira, N. G.; Greenberg, N. L.; Prior, D. L.; McCarthy, P. M.; Garcia, M. J.; Thomas, J. D.

2001-01-01

BACKGROUND: Early diastolic intraventricular pressure gradients (IVPGs) have been proposed to relate to left ventricular (LV) elastic recoil and early ventricular "suction." Animal studies have demonstrated relationships between IVPGs and systolic and diastolic indices during acute ischemia. However, data on the effects of improvements in LV function in humans and the relationship to IVPGs are lacking. METHODS AND RESULTS: Eight patients undergoing CABG and/or infarct exclusion surgery had a triple-sensor high-fidelity catheter placed across the mitral valve intraoperatively for simultaneous recording of left atrial (LA), basal LV, and apical LV pressures. Hemodynamic data obtained before bypass were compared with those with similar LA pressures and heart rates obtained after bypass. From each LV waveform, the time constant of LV relaxation (tau), +dP/dt(max), and -dP/dt(max) were determined. Transesophageal echocardiography was used to determined end-diastolic (EDV) and end-systolic (ESV) volumes and ejection fractions (EF). At similar LA pressures and heart rates, IVPG increased after bypass (before bypass 1.64+/-0.79 mm Hg; after bypass 2.67+/-1.25 mm Hg; P<0.01). Significant improvements were observed in ESV, as well as in apical and basal +dP/dt(max), -dP/dt(max), and tau (each P<0.05). Overall, IVPGs correlated inversely with both ESV (IVPG=-0.027[ESV]+3.46, r=-0.64) and EDV (IVPG=-0.027[EDV]+4.30, r=-0.70). Improvements in IVPGs correlated with improvements in apical tau (Deltatau =5.93[DeltaIVPG]+4.76, r=0.91) and basal tau (Deltatau =2.41[DeltaIVPG]+5.13, r=-0.67). Relative changes in IVPGs correlated with changes in ESV (DeltaESV=-0.97[%DeltaIVPG]+23.34, r=-0.79), EDV (DeltaEDV=-1.16[%DeltaIVPG]+34.92, r=-0.84), and EF (DeltaEF=0.38[%DeltaIVPG]-8.39, r=0.85). CONCLUSIONS: Improvements in LV function also increase IVPGs. These changes in IVPGs, suggestive of increases in LV suction and elastic recoil, correlate directly with improvements in LV relaxation and ESV.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bettoni, Dario; Nusser, Adi; Blas, Diego

We develop the framework for testing Lorentz invariance in the dark matter sector using galactic dynamics. We consider a Lorentz violating (LV) vector field acting on the dark matter component of a satellite galaxy orbiting in a host halo. We introduce a numerical model for the dynamics of satellites in a galactic halo and for a galaxy in a rich cluster to explore observational consequences of such an LV field. The orbital motion of a satellite excites a time dependent LV force which greatly affects its internal dynamics. Our analysis points out key observational signatures which serve as probes ofmore » LV forces. These include modifications to the line of sight velocity dispersion, mass profiles and shapes of satellites. With future data and a more detailed modeling these signatures can be exploited to constrain a new region of the parameter space describing the LV in the dark matter sector.« less

Left ventricular function impairment in patients with normal-weight obesity: contribution of abdominal fat deposition, profibrotic state, reduced insulin sensitivity, and proinflammatory activation.

PubMed

Kosmala, Wojciech; Jedrzejuk, Diana; Derzhko, Roksolana; Przewlocka-Kosmala, Monika; Mysiak, Andrzej; Bednarek-Tupikowska, Grazyna

2012-05-01

Obesity predisposes to left ventricular (LV) dysfunction and heart failure; however, the risk of these complications has not been assessed in patients with a normal body mass index (BMI) but increased body fat content (normal-weight obesity, NWO). We hypothesized that LV performance in NWO may be impaired and sought to investigate potential contributors to cardiac functional abnormalities. One hundred sixty-eight subjects (age, 38±7 years) with BMI <25kg/m(2) and no history of any disease affecting the myocardium were classified on the basis of body fat content into 2 groups: with NWO and without NWO. Echocardiographic indices of LV systolic and diastolic function, including myocardial velocities and deformation, serological fibrosis markers, indicators of proinflammatory activation, and metabolic control, were evaluated. Subjects with NWO demonstrated impaired LV systolic and diastolic function, increased fibrosis intensity (assessed by procollagen type I carboxy-terminal propeptide [PICP]), impaired insulin sensitivity, and increased proinflammatory activation as compared with individuals with normal body fat. The independent correlates of LV systolic and diastolic function variables were as follows: for strain, IL-18 (β=-0.17, P<0.006), C-reactive protein (β=-0.20, P<0.002) and abdominal fat deposit (β=-0.20, P<0.003); for tissue S velocity, PICP (β=-0.21, P<0.002) and abdominal fat deposit (β=-0.43, P<0.0001); for tissue E velocity, abdominal fat deposit (β=-0.30, P<0.0001), PICP (β=-0.31, P<0.0001) and homeostasis model assessment of insulin resistance index (HOMA IR; β=-0.20, P<0.002); and for E/e'-PICP, IL-18 (both β=0.18, P<0.01) and HOMA IR (β=0.16, P<0.04). In patients with NWO, subclinical disturbances of LV function are independently associated with the extent of abdominal fat deposit, profibrotic state (as reflected by circulating PICP), reduced insulin sensitivity, and proinflammatory activation.

Flow Behavior in the Left Heart Ventricle Following Apico-Aortic Bypass Surgery

NASA Astrophysics Data System (ADS)

Shahriari, Shahrokh; Jeyhani, Morteza; Labrosse, Michel; Kadem, Lyes

2013-11-01

Apico-aortic bypass (AAB) surgery is an alternative for transcatheter aortic valve implantation (TAVI) to reduce left ventricle (LV) overload in patients with severe aortic stenosis (AS). It consists in connecting the apex of the LV to the descending thoracic aorta with a valved conduit. Postoperative flow assessments show that two thirds of the outflow is conducted from the LV apex to the conduit, while only one third crosses the native aortic valve. In this study, we performed high speed particle image velocimetry (PIV) measurements of flow pattern within an in vitro elastic model of LV in the presence of a very severe AS, before and after AAB. Results indicate that AAB effectively relieves the LV outflow obstruction; however, it also leads to abnormal ventricular flow patterns. Normal LV flow dynamics is characterized by an emerging mitral jet flow followed by the development of a vortical flow with velocities directed towards the aortic valve, while measurements in the presence of AAB show systolic flow bifurcating to the apical conduit and to the aortic valve outflow tract. This study provides the first insight into the LV flow structure after AAB including outflow jets and disturbed stagnation regions.

Feasibility of rapid and automated importation of 3D echocardiographic left ventricular (LV) geometry into a finite element (FEM) analysis model

PubMed Central

Verhey, Janko F; Nathan, Nadia S

2004-01-01

Background Finite element method (FEM) analysis for intraoperative modeling of the left ventricle (LV) is presently not possible. Since 3D structural data of the LV is now obtainable using standard transesophageal echocardiography (TEE) devices intraoperatively, the present study describes a method to transfer this data into a commercially available FEM analysis system: ABAQUS©. Methods In this prospective study TomTec LV Analysis TEE© Software was used for semi-automatic endocardial border detection, reconstruction, and volume-rendering of the clinical 3D echocardiographic data. A newly developed software program MVCP FemCoGen©, written in Delphi, reformats the TomTec file structures in five patients for use in ABAQUS and allows visualization of regional deformation of the LV. Results This study demonstrates that a fully automated importation of 3D TEE data into FEM modeling is feasible and can be efficiently accomplished in the operating room. Conclusion For complete intraoperative 3D LV finite element analysis, three input elements are necessary: 1. time-gaited, reality-based structural information, 2. continuous LV pressure and 3. instantaneous tissue elastance. The first of these elements is now available using the methods presented herein. PMID:15473901

Acute effects of febuxostat, a nonpurine selective inhibitor of xanthine oxidase, in pacing induced heart failure.

PubMed

Hou, Mingxiao; Hu, Qingsong; Chen, Yingjie; Zhao, Lin; Zhang, Jianyi; Bache, Robert J

2006-11-01

We investigated whether xanthine oxidase inhibition with febuxostat enhances left ventricular (LV) function and improves myocardial high energy phosphates (HEP) in dogs with pacing-induced heart failure (CHF). Febuxostat (2.2 mg/kg over 10 minutes followed by 0.06 mg/kg/min) caused no change of LV function or myocardial oxygen consumption (MVO2) at rest or during treadmill exercise in normal dogs. In dogs with CHF, febuxostat increased LV dP/dtmax at rest and during heavy exercise (P < 0.05), indicating improved LV function with no change of MVO2. Myocardial adenosine triphosphate (ATP) and phosphocreatine (PCr) were examined using 31P nuclear magnetic resonance spectroscopy in the open chest state. In normal dogs, febuxostat increased PCr/ATP during basal conditions and during high workload produced by dobutamine + dopamine (P < 0.05). PCr/ATP was decreased in animals with CHF; in these animals, febuxostat (given after completing basal and high workload measurements with vehicle) tended to increase PCr/ATP during basal conditions with no effect during catecholamine stimulation. Thus, febuxostat improved LV performance in awake dogs with CHF, but caused only a trend toward increased PCr/ATP in the open chest state. It is possible that the antecedent high workload condition prior to drug administration blunted the effect of febuxostat on HEP in the CHF animals. Alternatively, beneficial effects of febuxostat on LV performance in the failing heart may not involve HEP.

Outcomes of Left Ventricular Function According to Treatment Response for a Patent Ductus Arteriosus in Preterm Infants

PubMed Central

Cho, Young Sun; Hwang, Seo Jung; Kim, Hyo Jin

2017-01-01

Background To evaluate the outcomes of left ventricular (LV) function according to treatment response for a hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. Methods Echocardiograms of 21 preterm infants born at gestational age < 31 weeks obtained at term-equivalent age were retrospectively studied. Among preterm infants with a hsPDA, 9 underwent ligation after failure of pharmacological closure (ligation group) and 6 experienced successful pharmacological closure (medication group). Six preterm infants without hsPDA (no-hsPDA group) were studied as controls. LV peak longitudinal systolic strain (ε) of each infant was retrospectively obtained from echocardiograms using velocity vector imaging, along with neonatal outcomes. Results Pharmacological closures were attempted at postnatal day 2–3. In the ligation group, the median postnatal age at ligation was 20 days. In the ligation group, LV peak longitudinal systolic ε was significantly decreased at term-equivalent age compared to the other groups. Between the medication and no-hsPDA groups, LV peak longitudinal systolic ε did not differ significantly. Among the neonatal outcomes, infants who experienced necrotizing enterocolitis (NEC) showed significantly decreased LV peak longitudinal systolic ε compared to the infants who did not experience NEC . Conclusion We speculate that in preterm infants with an hsPDA, in cases of medical treatment failure, early PDA ligation at less than 20 days of postnatal age would be beneficial for preserving LV systolic function. PMID:29333220

An automatic alignment tool to improve repeatability of left ventricular function and dyssynchrony parameters in serial gated myocardial perfusion SPECT studies

PubMed Central

Zhou, Yanli; Faber, Tracy L.; Patel, Zenic; Folks, Russell D.; Cheung, Alice A.; Garcia, Ernest V.; Soman, Prem; Li, Dianfu; Cao, Kejiang; Chen, Ji

2013-01-01

Objective Left ventricular (LV) function and dyssynchrony parameters measured from serial gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) using blinded processing had a poorer repeatability than when manual side-by-side processing was used. The objective of this study was to validate whether an automatic alignment tool can reduce the variability of LV function and dyssynchrony parameters in serial gated SPECT MPI. Methods Thirty patients who had undergone serial gated SPECT MPI were prospectively enrolled in this study. Thirty minutes after the first acquisition, each patient was repositioned and a gated SPECT MPI image was reacquired. The two data sets were first processed blinded from each other by the same technologist in different weeks. These processed data were then realigned by the automatic tool, and manual side-by-side processing was carried out. All processing methods used standard iterative reconstruction and Butterworth filtering. The Emory Cardiac Toolbox was used to measure the LV function and dyssynchrony parameters. Results The automatic tool failed in one patient, who had a large, severe scar in the inferobasal wall. In the remaining 29 patients, the repeatability of the LV function and dyssynchrony parameters after automatic alignment was significantly improved from blinded processing and was comparable to manual side-by-side processing. Conclusion The automatic alignment tool can be an alternative method to manual side-by-side processing to improve the repeatability of LV function and dyssynchrony measurements by serial gated SPECT MPI. PMID:23211996

Changes in collagen metabolism account for ventricular functional recovery following beta-blocker therapy in patients with chronic heart failure.

PubMed

Fukui, Miho; Goda, Akiko; Komamura, Kazuo; Nakabo, Ayumi; Masaki, Mitsuru; Yoshida, Chikako; Hirotani, Shinichi; Lee-Kawabata, Masaaki; Tsujino, Takeshi; Mano, Toshiaki; Masuyama, Tohru

2016-02-01

While beta blockade improves left ventricular (LV) function in patients with chronic heart failure (CHF), the mechanisms are not well known. This study aimed to examine whether changes in myocardial collagen metabolism account for LV functional recovery following beta-blocker therapy in 62 CHF patients with reduced ejection fraction (EF). LV function was echocardiographically measured at baseline and 1, 6, and 12 months after bisoprolol therapy along with serum markers of collagen metabolism including C-terminal telopeptide of collagen type I (CITP) and matrix metalloproteinase (MMP)-2. Deceleration time of mitral early velocity (DcT) increased even in the early phase, but LVEF gradually improved throughout the study period. Heart rate (HR) was reduced from the early stage, and CITP gradually decreased. LVEF and DcT increased more so in patients with the larger decreases in CITP (r = -0.33, p < 0.05; r = -0.28, p < 0.05, respectively), and HR (r = -0.31, p < 0.05; r = -0.38, p < 0.05, respectively). In addition, there were greater decreases in CITP, MMP-2 and HR from baseline to 1, 6, or 12 months in patients with above-average improvement in LVEF than in those with below-average improvement in LVEF. Similar results were obtained in terms of DcT. There was no significant correlation between the changes in HR and CITP. In conclusion, improvement in LV systolic/diastolic function was greatest in patients with the larger inhibition of collagen degradation. Changes in myocardial collagen metabolism are closely related to LV functional recovery somewhat independently from HR reduction.

Comparison of endogenous feline leukemia virus RNA content in feline vaccine and nonvaccine site-associated sarcomas.

PubMed

Kidney, B A; Ellis, J A; Haines, D M; Jackson, M L

2001-12-01

To determine whether feline vaccine site-associated sarcomas (VSS) contain a higher amount of endogenous FeLV (enFeLV) RNA, compared with feline nonvaccine site-associated sarcomas (non-VSS). Formalin-fixed paraffin-embedded (FFPE) tissues from 50 VSS and 50 cutaneous non-VSS. RNA was extracted from FFPE sections of each tumor, and regions of the long terminal repeat (LTR) and envelope (env) gene of enFeLV were amplified by use of reverse transcriptase-polymerase chain reaction (RT-PCR). The density of each RT-PCR product band for enFeLV was compared with that of a constitutively expressed gene, glyceraldehyde-3-phosphate dehydrogenase (GAPDH). An integrated density value (IDV) was determined by use of densitometry, and the IDV ratio for enFeLV to GAPDH was calculated for each enFeLV primer set. The median (interquartile range) of the IDV ratio for the enFeLV LTR primer set was 0.52 (0.26 to 1.17) for the VSS group and 0.84 (0.21 to 1.53) for the non-VSS group. The median (interquartile range) of the IDV ratio for the enFeLV env primer set was 0.60 (0.37 to 0.91) for the VSS group and 0.59 (0.36 to 1.09) for the non-VSS group. Because the amount of enFeLV RNA within the LTR and env gene was not significantly different between the VSS and non-VSS groups, enFeLV replication or expression is unlikely to be involved in VSS development.

Left Ventricular Dysfunction and Dilated Cardiomyopathy in Infants and Children with Wolff-Parkinson-White Syndrome in the Absence of Tachyarrhythmias

PubMed Central

2012-01-01

Left ventricular (LV) dysfunction and dilated cardiomyopathy (DCM) are rarely attributable to sustained or incessant tachyarrhythmias in infants and children with Wolff-Parkinson-White (WPW) syndrome. However, several recent reports suggested that significant LV dysfunction may develop in WPW syndrome in the absence of tachyarrhythmias. It is assumed that an asynchronous ventricular activation over the accessory pathway, especially right-sided, induces septal wall motion abnormalities, ventricular remodeling and ventricular dysfunction. The prognosis of DCM associated with asymptomatic WPW is excellent. Loss of ventricular pre-excitation results in mechanical resynchronization and reverse remodeling where LV function recovers completely. The reversible nature of LV dysfunction after loss of ventricular pre-excitation supports the causal relationship between LV dysfunction and ventricular pre-excitation. This review summarizes recent clinical and electrophysiological evidence for development of LV dysfunction or DCM in asymptomatic WPW syndrome, and discusses the underlying pathophysiological mechanism. PMID:23323117

High prevalence of cardiac hypertophy without detectable signs of fibrosis in patients with untreated active acromegaly: an in vivo study using magnetic resonance imaging.

PubMed

Bogazzi, Fausto; Lombardi, Massimo; Strata, Elisabetta; Aquaro, Giovanni; Di Bello, Vitantonio; Cosci, Chiara; Sardella, Chiara; Talini, Enrica; Martino, Enio

2008-03-01

Left ventricular (LV) hypertrophy and myocardial fibrosis are considered the main pathological features of acromegalic cardiomyopathy. The aim of the study was to evaluate the proportion of LV hypertrophy and the presence of fibrosis in acromegalic cardiomyopathy in vivo using cardiac magnetic resonance (CMR). Fourteen consecutive patients (eight women, mean age 46 +/- 10 years) with untreated active acromegaly were submitted to two-dimensional (2D) colour Doppler and integrated backscatter (IBS) echocardiography and CMR. LV volume, mass and wall thickness and myocardial tissue characterization (IBS and CMR). On echocardiography: mean LV mass (LVM) and LVM index (LVMi) were 209 +/- 48 g and 110 +/- 24 g/m(2), respectively; hypertrophy was revealed in five patients (36%); abnormal diastolic function [evaluated by isovolumic relaxation time (IVRT) or early (E) to late or atrial (A) peak velocities (E/A ratio)] was found in four patients (29%). Systolic function evaluated by measuring LV ejection fraction (LVEF) was normal (mean 72 +/- 12%) in all patients. Six patients (43%) had increased IBS (mean 57.4 +/- 6.2%). On CMR: mean LVM and LVMi were 151 +/- 17 g and 76 +/- 9 g/m(2), respectively; 10 patients (72%) had LV hypertrophy. Contrastographic delayed hyperenhancement was absent in all patients; on the contrary, mild enhancement was revealed in one patient. Systolic function was normal in all patients (LVEF 67 +/- 11%). LVMi was not related to serum IGF-1 concentrations or the estimated duration of disease. CMR is considered to be the gold standard for evaluating cardiac hypertrophy, fibrosis and systolic function. Using CMR, 72% patients with untreated active acromegaly had LV hypertrophy, which was only detected in 36% patients by echocardiography. However, cardiac fibrosis was absent in all patients irrespective of the estimated duration of disease. Although a very small increase in collagen content (as suggested by increased cardiac reflectivity at IBS), not detectable by CMR, could not be ruled out, it is unlikely that it would significantly affect cardiac function.

Relationship between mitral annulus function and mitral regurgitation severity and left atrial remodelling in patients with primary mitral regurgitation.

PubMed

Mihaila, Sorina; Muraru, Denisa; Miglioranza, Marcelo Haertel; Piasentini, Eleonora; Aruta, Patrizia; Cucchini, Umberto; Iliceto, Sabino; Vinereanu, Dragos; Badano, Luigi P

2016-08-01

To explore the relationship between the mitral annular (MA) remodelling and dysfunction, mitral regurgitation (MR) severity, left ventricular (LV) and atrial (LA) size and function in patients with organic MR (OMR). A total of 52 patients (57 ± 15 years, 31 men) with mild to severe OMR and 52 controls underwent 3D transthoracic echocardiography acquisitions of the mitral valve (MV), LA, and LV. MA geometry and dynamics, LV and LA volumes, LV ejection fraction (LVEF) and emptying fractions (LAEF) were assessed using dedicated software packages. LA and LV myocardial deformations were assessed using 2D speckle-tracking echocardiography. OMR patients presented larger and more spherical MA than controls during the entire systole (P < 0.001). Although the MA non-planarity at early-systole was similar between OMR and controls (157 ± 13° vs. 153 ± 12°, P = NS), the MA became flatter from mid- to end-systole (153 ± 12 vs. 146 ± 10° and 157 ± 12 vs. 147 ± 8°, P < 0.01) in OMR. MA area fractional change was lower in patients with OMR (22 ± 5% vs. 28 ± 5%, P < 0.001), and correlated with the MR orifice and volume (r = -0.52 and r = -0.55). MA fractional area change correlated with LA minimum and maximum volumes (r = 0.77 and r = 0.70), total and active LAEF (r = 0.72 and r = 0.76), and LA negative strain and strain rate (r = 0.52 and r = 0.57), but not with the LVEF or LV global longitudinal strain. In a multivariate regression model using LAEF and LVEF, solely active LAEF correlated with the MA fractional area change (β = 0.51, P = 0.005). In patients with OMR, MA reduced function correlates with the MR severity and the LA size and function, but not with the LV function. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Effects of Obstructive Sleep Apnea and Obesity on Cardiac Remodeling: The Wisconsin Sleep Cohort Study.

PubMed

Korcarz, Claudia E; Peppard, Paul E; Young, Terry B; Chapman, Carrie B; Hla, K Mae; Barnet, Jodi H; Hagen, Erika; Stein, James H

2016-06-01

To characterize the prospective associations of obstructive sleep apnea (OSA) with future echocardiographic measures of adverse cardiac remodeling. This was a prospective long-term observational study. Participants had overnight polysomnography followed by transthoracic echocardiography a mean (standard deviation) of 18.0 (3.7) y later. OSA was characterized by the apnea-hypopnea index (AHI, events/hour). Echocardiography was used to assess left ventricular (LV) systolic and diastolic function and mass, left atrial volume and pressure, cardiac output, systemic vascular resistance, and right ventricular (RV) systolic function, size, and hemodynamics. Multivariate regression models estimated associations between log10(AHI+1) and future echocardiographic findings. A secondary analysis looked at oxygen desaturation indices and future echocardiographic findings. At entry, the 601 participants were mean (standard deviation) 47 (8) y old (47% female). After adjustment for age, sex, and body mass index, baseline log10(AHI+1) was associated significantly with future reduced LV ejection fraction and tricuspid annular plane systolic excursion (TAPSE) ≤ 15 mm. After further adjustment for cardiovascular risk factors, participants with higher baseline log10(AHI+1) had lower future LV ejection fraction (β = -1.35 [standard error = 0.6]/log10(AHI+1), P = 0.03) and higher odds of TAPSE ≤ 15 mm (odds ratio = 6.3/log10(AHI+1), 95% confidence interval = 1.3-30.5, P = 0.02). SaO2 desaturation indices were associated independently with LV mass, LV wall thickness, and RV area (all P < 0.03). OSA is associated independently with decreasing LV systolic function and with reduced RV function. Echocardiographic measures of adverse cardiac remodeling are strongly associated with OSA but are confounded by obesity. Hypoxia may be a stimulus for hypertrophy in individuals with OSA. © 2016 Associated Professional Sleep Societies, LLC.

Biventricular Heart Remodeling After Percutaneous or Surgical Pulmonary Valve Implantation: Evaluation by Cardiac Magnetic Resonance.

PubMed

Secchi, Francesco; Resta, Elda C; Cannaò, Paola M; Pluchinotta, Francesca; Piazza, Luciane; Butera, Gianfranco; Carminati, Mario; Sardanelli, Francesco

2017-11-01

The aim of this study was to evaluate the impact of percutaneous pulmonary valve implantation (PPVI) and surgical pulmonary valve replacement (SPVR) on biventricular and pulmonary valve function using cardiac magnetic resonance. Thirty-five patients aged 20±8 years (mean±SD) underwent PPVI, whereas 16 patients aged 30±11 years underwent SPVR. Cardiac magnetic resonance examinations were performed before and after the procedures with an average follow-up interval of 10 months. Cine steady-state free precession sequences for cardiac function and phase-contrast sequences for pulmonary flow were performed. The right ventricle (RV) and left ventricle (LV) functions were evaluated using a dedicated software. The RV end-diastolic volume index (mL/m) decreased significantly after PPVI and SPVR, from 74 to 64 (P=0.030) and from 137 to 83 (P=0.001), respectively. The RV ejection fraction increased significantly after SPVR, from 47% to 53% (P=0.038). The LV end-diastolic volume index increased significantly after PPVI, from 66 to 76 mL/m (P<0.001). The LV stroke volume index increased significantly after PPVI, from 34 to 43 mL/m (P=0.004). The analysis of bivariate correlations showed that in patients undergoing SPVR the RV changes after the procedure were positively correlated to LV changes in terms of end-systolic volume index (r=0587; P=0.017) and ejection fraction (r=0.681; P=0.004). A RV volumetric reduction and a positive effect on ventricular-ventricular interaction were observed after both PPVI and SPVR. After PPVI, a positive volumetric LV remodeling was found. No LV remodeling was found after SPVR. After both procedures, the replaced pulmonary valve functioned well.

Right ventricular dysfunction after resuscitation predicts poor outcomes in cardiac arrest patients independent of left ventricular function.

PubMed

Ramjee, Vimal; Grossestreuer, Anne V; Yao, Yuan; Perman, Sarah M; Leary, Marion; Kirkpatrick, James N; Forfia, Paul R; Kolansky, Daniel M; Abella, Benjamin S; Gaieski, David F

2015-11-01

Determination of clinical outcomes following resuscitation from cardiac arrest remains elusive in the immediate post-arrest period. Echocardiographic assessment shortly after resuscitation has largely focused on left ventricular (LV) function. We aimed to determine whether post-arrest right ventricular (RV) dysfunction predicts worse survival and poor neurologic outcome in cardiac arrest patients, independent of LV dysfunction. A single-center, retrospective cohort study at a tertiary care university hospital participating in the Penn Alliance for Therapeutic Hypothermia (PATH) Registry between 2000 and 2012. 291 in- and out-of-hospital adult cardiac arrest patients at the University of Pennsylvania who had return of spontaneous circulation (ROSC) and post-arrest echocardiograms. Of the 291 patients, 57% were male, with a mean age of 59 ± 16 years. 179 (63%) patients had LV dysfunction, 173 (59%) had RV dysfunction, and 124 (44%) had biventricular dysfunction on the initial post-arrest echocardiogram. Independent of LV function, RV dysfunction was predictive of worse survival (mild or moderate: OR 0.51, CI 0.26-0.99, p<0.05; severe: OR 0.19, CI 0.06-0.65, p=0.008) and neurologic outcome (mild or moderate: OR 0.33, CI 0.17-0.65, p=0.001; severe: OR 0.11, CI 0.02-0.50, p=0.005) compared to patients with normal RV function after cardiac arrest. Echocardiographic findings of post-arrest RV dysfunction were equally prevalent as LV dysfunction. RV dysfunction was significantly predictive of worse outcomes in post-arrest patients after accounting for LV dysfunction. Post-arrest RV dysfunction may be useful for risk stratification and management in this high-mortality population. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Mitral annular plane systolic excursion/left ventricular length (MAPSE/L) as a simple index for assessing left ventricular longitudinal function in children.

PubMed

Terada, Tomomasa; Mori, Kazuhiro; Inoue, Miki; Yasunobu, Hayabuchi

2016-11-01

Assessment of longitudinal left ventricular (LV) function is important for early detection of cardiac dysfunction. Although mitral annular plane systolic excursion (MAPSE) obtained by M-mode echocardiography offers a simple method for assessing longitudinal LV function, normal values of MAPSE for children change according to body size. To minimize the effects of body size, MAPSE was divided by LV long-axis length (MAPSE/L). MAPSE/L was measured in 210 healthy children from birth to 15 years of age and classified into five subgroups. MAPSE/L was then compared with 10 parameters in 136 children (age, heart rate, mean blood pressure, ejection fraction of the LV (EF), peak atrial flow velocity/peak early diastolic flow velocity of mitral flow, tissue Doppler velocity during systole (s') and early diastole (e'), E/e' ratio, Tei index, and global longitudinal strain (GLS) of the LV by the speckle tracking method). MAPSE/L was significantly lower in the neonate group than in the remaining four groups. MAPSE/L then increased with age to peak at 1-5 years and gradually decreased thereafter. In all cases beyond the neonatal period, MAPSE/L was more than 0.17. Among various parameters, GLS, age, EF, Tei index and s' were significantly associated with MAPSE/L in that order. In univariate analysis, GLS was most significantly associated with MAPSE/L (r=.56). We have established normal reference values for MPSE/L in healthy children. MAPSE/L is expected to offer a simple parameter to evaluate LV longitudinal systolic function during daily routine echocardiography in children. © 2016, Wiley Periodicals, Inc.

Left-Ventricular Energetics in Pulmonary Arterial Hypertension-Induced Right-Ventricular Hypertrophic Failure

PubMed Central

Han, June-Chiew; Guild, Sarah-Jane; Pham, Toan; Nisbet, Linley; Tran, Kenneth; Taberner, Andrew J.; Loiselle, Denis S.

2018-01-01

Pulmonary arterial hypertension (PAH) alters the geometries of both ventricles of the heart. While the right ventricle (RV) hypertrophies, the left ventricle (LV) atrophies. Multiple lines of clinical and experimental evidence lead us to hypothesize that the impaired stroke volume and systolic pressure of the LV are a direct consequence of the effect of pressure overload in the RV, and that atrophy in the LV plays only a minor role. In this study, we tested this hypothesis by examining the mechanoenergetic response of the atrophied LV to RV hypertrophy in rats treated with monocrotaline. Experiments were performed across multiple-scales: the whole-heart in vivo and ex vivo, and its trabeculae in vitro. Under the in vivo state where the RV was pressure-overloaded, we measured reduced systemic blood pressure and LV ventricular pressure. In contrast, under both ex vivo and in vitro conditions, where the effect of RV pressure overload was circumvented, we found that LV was capable of developing normal systolic pressure and stress. Nevertheless, LV atrophy played a minor role in that LV stroke volume remained lower, thereby contributing to lower LV mechanical work output. Concomitantly lower oxygen consumption and change of enthalpy were observed, and hence LV energy efficiency was unchanged. Our internally consistent findings between working-heart and trabecula experiments explain the rapid improvement of LV systolic function observed in patients with chronic pulmonary hypertension following surgical relief of RV pressure overload. PMID:29375394

IFATS Collection: Human Adipose Tissue-Derived Stem Cells Induce Angiogenesis and Nerve Sprouting Following Myocardial Infarction, in Conjunction with Potent Preservation of Cardiac Function

PubMed Central

Cai, Liying; Johnstone, Brian H.; Cook, Todd G.; Tan, Jian; Fishbein, Michael C.; Chen, Peng-Sheng; March, Keith L.

2010-01-01

The administration of therapeutic cell types, such as stem and progenitor cells, has gained much interest for the limitation or repair of tissue damage caused by a variety of insults. However, it is still uncertain whether the morphological and functional benefits are mediated predominantly via cell differentiation or paracrine mechanisms. Here, we assessed the extent and mechanisms of adipose-derived stromal/stem cells (ASC)-dependent tissue repair in the context of acute myocardial infarction. Human ASCs in saline or saline alone was injected into the peri-infarct region in athymic rats following left anterior descending (LAD) coronary artery ligation. Cardiac function and structure were evaluated by serial echocardiography and histology. ASC-treated rats consistently exhibited better cardiac function, by all measures, than control rats 1 month following LAD occlusion. Left ventricular (LV) ejection fraction and fractional shortening were improved in the ASC group, whereas LV remodeling and dilation were limited in the ASC group compared with the saline control group. Anterior wall thinning was also attenuated by ASC treatment, and post-mortem histological analysis demonstrated reduced fibrosis in ASC-treated hearts, as well as increased peri-infarct density of both arterioles and nerve sprouts. Human ASCs were persistent at 1 month in the peri-infarct region, but they were not observed to exhibit significant cardiomyocyte differentiation. Human ASCs preserve heart function and augment local angiogenesis and cardiac nerve sprouting following myocardial infarction predominantly by the provision of beneficial trophic factors. PMID:18772313

Noninvasive evaluation of global and regional left ventricular function using computed tomography and magnetic resonance imaging: a meta-analysis.

PubMed

Kaniewska, Malwina; Schuetz, Georg M; Willun, Steffen; Schlattmann, Peter; Dewey, Marc

2017-04-01

To compare the diagnostic accuracy of computed tomography (CT) in the assessment of global and regional left ventricular (LV) function with magnetic resonance imaging (MRI). MEDLINE, EMBASE and ISI Web of Science were systematically reviewed. Evaluation included: ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and left ventricular mass (LVM). Differences between modalities were analysed using limits of agreement (LoA). Publication bias was measured by Egger's regression test. Heterogeneity was evaluated using Cochran's Q test and Higgins I 2 statistic. In the presence of heterogeneity the DerSimonian-Laird method was used for estimation of heterogeneity variance. Fifty-three studies including 1,814 patients were identified. The mean difference between CT and MRI was -0.56 % (LoA, -11.6-10.5 %) for EF, 2.62 ml (-34.1-39.3 ml) for EDV and 1.61 ml (-22.4-25.7 ml) for ESV, 3.21 ml (-21.8-28.3 ml) for SV and 0.13 g (-28.2-28.4 g) for LVM. CT detected wall motion abnormalities on a per-segment basis with 90 % sensitivity and 97 % specificity. CT is accurate for assessing global LV function parameters but the limits of agreement versus MRI are moderately wide, while wall motion deficits are detected with high accuracy. • CT helps to assess patients with coronary artery disease (CAD). • MRI is the reference standard for evaluation of left ventricular function. • CT provides accurate assessment of global left ventricular function.

[Efficacy of siRNA on feline leukemia virus replication in vitro].

PubMed

Lehmann, Melanie; Weber, Karin; Rauch, Gisep; Hofmann-Lehmann, Regina; Hosie, Margaret J; Meli, Marina L; Hartmann, Katrin

2015-01-01

Feline leukemia virus (FeLV) can lead to severe clinical signs in cats. Until now, there is no effective therapy for FeLV-infected cats. RNA interference-based antiviral therapy is a new concept. Specific small interfering RNA (siRNA) are designed complementary to the mRNA of a target region, and thus inhibit replication. Several studies have proven efficacy of siRNAs in inhibiting virus replication. The aim of this study was to evaluate the inhibitory potential of siRNAs against FeLV replication in vitro. siRNAs against the FeLV env gene and the host cell surface receptor (feTHTR1) which is used by FeLV-A for entry as well as siRNA that were not complementary to the FeLV or cat genome, were tested. Crandell feline kidney cells (CrFK cells) were transfected with FeLV-A/Glasgow-1. On day 13, infected cells were transfected with siRNAs. As control, cells were mock-transfected or treated with azidothymidine (AZT) (5 μg/ml). Culture supernatants were analyzed for FeLV RNA using quantitative real-time RT-PCR and for FeLV p27 by ELISA every 24 hours for five days. All siRNAs significantly reduced viral RNA and p27 production, starting after 48 hours. The fact that non-complementary siRNAs also inhibited virus replication may lead to the conclusion that unspecific mechanisms rather than specific binding lead to inhibition.

Implication of a Central Cysteine Residue and the HHCC Domain of Moloney Murine Leukemia Virus Integrase Protein in Functional Multimerization

PubMed Central

Donzella, George A.; Leon, Oscar; Roth, Monica J.

1998-01-01

Moloney murine leukemia virus (M-MuLV) IN-IN protein interactions important for catalysis of strand transfer and unimolecular and bimolecular disintegration reactions were investigated by using a panel of chemically modified M-MuLV IN proteins. Functional complementation of an HHCC-deleted protein (NΔ105) by an independent HHCC domain (CΔ232) was severely compromised by NEM modification of either subunit. Productive NΔ105 IN-DNA interactions with a disintegration substrate lacking a long terminal repeat 5′-single-stranded tail also required complementation by a functional HHCC domain. Virus encoding the C209A M-MuLV IN mutation exhibited delayed virion production and replication kinetics. PMID:9445080

A Feline HFpEF Model with Pulmonary Hypertension and Compromised Pulmonary Function.

PubMed

Wallner, Markus; Eaton, Deborah M; Berretta, Remus M; Borghetti, Giulia; Wu, Jichuan; Baker, Sandy T; Feldsott, Eric A; Sharp, Thomas E; Mohsin, Sadia; Oyama, Mark A; von Lewinski, Dirk; Post, Heiner; Wolfson, Marla R; Houser, Steven R

2017-11-29

Heart Failure with preserved Ejection Fraction (HFpEF) represents a major public health problem. The causative mechanisms are multifactorial and there are no effective treatments for HFpEF, partially attributable to the lack of well-established HFpEF animal models. We established a feline HFpEF model induced by slow-progressive pressure overload. Male domestic short hair cats (n = 20), underwent either sham procedures (n = 8) or aortic constriction (n = 12) with a customized pre-shaped band. Pulmonary function, gas exchange, and invasive hemodynamics were measured at 4-months post-banding. In banded cats, echocardiography at 4-months revealed concentric left ventricular (LV) hypertrophy, left atrial (LA) enlargement and dysfunction, and LV diastolic dysfunction with preserved systolic function, which subsequently led to elevated LV end-diastolic pressures and pulmonary hypertension. Furthermore, LV diastolic dysfunction was associated with increased LV fibrosis, cardiomyocyte hypertrophy, elevated NT-proBNP plasma levels, fluid and protein loss in pulmonary interstitium, impaired lung expansion, and alveolar-capillary membrane thickening. We report for the first time in HFpEF perivascular fluid cuff formation around extra-alveolar vessels with decreased respiratory compliance. Ultimately, these cardiopulmonary abnormalities resulted in impaired oxygenation. Our findings support the idea that this model can be used for testing novel therapeutic strategies to treat the ever growing HFpEF population.

Hippocampal Insulin Resistance Impairs Spatial Learning and Synaptic Plasticity

PubMed Central

Piroli, Gerardo G.; Lawrence, Robert C.; Wrighten, Shayna A.; Green, Adrienne J.; Wilson, Steven P.; Sakai, Randall R.; Kelly, Sandra J.; Wilson, Marlene A.; Mott, David D.; Reagan, Lawrence P.

2015-01-01

Insulin receptors (IRs) are expressed in discrete neuronal populations in the central nervous system, including the hippocampus. To elucidate the functional role of hippocampal IRs independent of metabolic function, we generated a model of hippocampal-specific insulin resistance using a lentiviral vector expressing an IR antisense sequence (LV-IRAS). LV-IRAS effectively downregulates IR expression in the rat hippocampus without affecting body weight, adiposity, or peripheral glucose homeostasis. Nevertheless, hippocampal neuroplasticity was impaired in LV-IRAS–treated rats. High-frequency stimulation, which evoked robust long-term potentiation (LTP) in brain slices from LV control rats, failed to evoke LTP in LV-IRAS–treated rats. GluN2B subunit levels, as well as the basal level of phosphorylation of GluA1, were reduced in the hippocampus of LV-IRAS rats. Moreover, these deficits in synaptic transmission were associated with impairments in spatial learning. We suggest that alterations in the expression and phosphorylation of glutamate receptor subunits underlie the alterations in LTP and that these changes are responsible for the impairment in hippocampal-dependent learning. Importantly, these learning deficits are strikingly similar to the impairments in complex task performance observed in patients with diabetes, which strengthens the hypothesis that hippocampal insulin resistance is a key mediator of cognitive deficits independent of glycemic control. PMID:26216852

Echocardiographic dimensions and function in adults with primary growth hormone resistance (Laron syndrome).

PubMed

Feinberg, M S; Scheinowitz, M; Laron, Z

2000-01-15

Patients with primary growth hormone (GH) resistance-Laron Syndrome (LS)-have no GH signal transmission, and thus, no generation of circulating insulin-like growth factor-I (IGF-I), and should serve as a unique model to explore the controversies concerning the longterm effect of GH/IGF-I deficiency on cardiac dimension and function. We assessed 8 patients with LS (4 men, 4 women) with a mean (+/- SD) age of 38+/-7 years (range 22 to 45), and 8 aged-matched controls (4 men, 4 women) with a mean age of 38+/-9 years (range 18 to 47) by echocardiography at rest, following exercise, and during dobutamine administration. Left ventricular (LV) septum, posterior wall, and end-diastolic diameter were significantly reduced in untreated patients with LS compared with the control group (p<0.05 for all). Systolic Doppler-derived parameters, including LV stroke volume, stroke index, cardiac output, and cardiac index, were significantly lower (p<0.05 for all) than in the control subjects, whereas LV diastolic Doppler parameters, including mitral valve waves E, A, E/A ratio, and E deceleration time, were similar in both groups. LV ejection fraction at rest as well as the stress-induced increment of the LV ejection fraction were similar in both groups. Our results show that untreated patients with long-term IGF-I deficiency have reduced cardiac dimensions and output but normal LV ejection fraction at rest and LV contractile reserve following stress.

Acute and chronic neuromuscular adaptations to local vibration training.

PubMed

Souron, Robin; Besson, Thibault; Millet, Guillaume Y; Lapole, Thomas

2017-10-01

Vibratory stimuli are thought to have the potential to promote neural and/or muscular (re)conditioning. This has been well described for whole-body vibration (WBV), which is commonly used as a training method to improve strength and/or functional abilities. Yet, this technique may present some limitations, especially in clinical settings where patients are unable to maintain an active position during the vibration exposure. Thus, a local vibration (LV) technique, which consists of applying portable vibrators directly over the tendon or muscle belly without active contribution from the participant, may present an alternative to WBV. The purpose of this narrative review is (1) to provide a comprehensive overview of the literature related to the acute and chronic neuromuscular changes associated with LV, and (2) to show that LV training may be an innovative and efficient alternative method to the 'classic' training programs, including in the context of muscle deconditioning prevention or rehabilitation. An acute LV application (one bout of 20-60 min) may be considered as a significant neuromuscular workload, as demonstrated by an impairment of force generating capacity and LV-induced neural changes. Accordingly, it has been reported that a training period of LV is efficient in improving muscular performance over a wide range of training (duration, number of session) and vibration (frequency, amplitude, site of application) parameters. The functional improvements are principally triggered by adaptations within the central nervous system. A model illustrating the current research on LV-induced adaptations is provided.

Relationship of left ventricular hypertrophy and diastolic function with cardiovascular and renal outcomes in African Americans with hypertensive chronic kidney disease.

PubMed

Peterson, Gail E; de Backer, Tine; Contreras, Gabriel; Wang, Xuelei; Kendrick, Cynthia; Greene, Tom; Appel, Lawrence J; Randall, Otelio S; Lea, Janice; Smogorzewski, Miroslaw; Vagaonescu, Tudor; Phillips, Robert A

2013-09-01

African Americans with hypertension are at high risk for adverse outcomes from cardiovascular and renal disease. Patients with stage 3 or greater chronic kidney disease have a high prevalence of left ventricular (LV) hypertrophy and diastolic dysfunction. Our goal was to study prospectively the relationships of LV mass and diastolic function with subsequent cardiovascular and renal outcomes in the African American Study of Kidney Disease and Hypertension cohort study. Of 691 patients enrolled in the cohort, 578 had interpretable echocardiograms and complete relevant clinical data. Exposures were LV hypertrophy and diastolic parameters. Outcomes were cardiovascular events requiring hospitalization or causing death; a renal composite outcome of doubling of serum creatinine or end-stage renal disease (censoring death); and heart failure. We found strong independent relationships between LV hypertrophy and subsequent cardiovascular (hazard ratio, 1.16; 95% confidence interval, 1.05-1.27) events, but not renal outcomes. After adjustment for LV mass and clinical variables, lower systolic tissue Doppler velocities and diastolic parameters reflecting a less compliant LV (shorter deceleration time and abnormal E/A ratio) were significantly (P<0.05) associated with future heart failure events. This is the first study to show a strong relationship among LV hypertrophy, diastolic parameters, and adverse cardiac outcomes in African Americans with hypertension and chronic kidney disease. These echocardiographic risk factors may help identify high-risk patients with chronic kidney disease for aggressive therapeutic intervention.

SERIAL ULTRASOUND EVALUATION OF INTRAMYOCARDIAL STRAIN AFTER REPERFUSED MYOCARDIAL INFARCTION REVEALS THAT REMOTE ZONE DYSSYNCHRONY DEVELOPS IN CONCERT WITH LEFT VENTRICULAR REMODELING

PubMed Central

Li, Yinbo; Garson, Christopher D.; Xu, Yaqin; Helm, Patrick A.; Hossack, John A.; French, Brent A.

2011-01-01

This study noninvasively evaluated the development of left ventricular (LV) dyssynchrony following reperfused myocardial infarction (MI) in mice using an ultrasonic speckle-tracking method. Eight C57BL/6J mice were assessed by high-resolution echocardiography at baseline and at eight time-points following MI. Images were acquired at 1mm elevational intervals encompassing the entire LV to determine chamber volumes and radial strain. Receiver-operating characteristic (ROC) analysis of regional radial strain was used to segment the three-dimensional (3-D) LV into infarct, adjacent and remote zones. This in vivo segmentation was correlated to histologic infarct size (R = 0.89, p < 0.01) in a short-axis, slice-by-slice comparison. The onset of dyssynchrony during LV remodeling was assessed by standard deviation of time to peak radial strain in the infarct, adjacent and remote zones. It was discovered that the form of LV dyssynchrony that develops in the remote zone late after MI does so in concert with the progression of LV remodeling (R = 0.70, p < 0.05). PMID:21640480

Expression of exogenous human hepatic nuclear factor-1α by a lentiviral vector and its interactions with Plasmodium falciparum subtilisin-like protease 2.

PubMed

Liao, Shunyao; Liu, Yunqiang; Zheng, Bing; Cho, Pyo Yun; Song, Hyun Ok; Lee, Yun-Seok; Jung, Suk-Yul; Park, Hyun

2011-12-01

The onset, severity, and ultimate outcome of malaria infection are influenced by parasite-expressed virulence factors as well as by individual host responses to these determinants. In both humans and mice, liver injury follows parasite entry, persisting to the erythrocytic stage in the case of infection with the fatal strain of Plasmodium falciparum. Hepatic nuclear factor (HNF)-1α is a master regulator of not only the liver damage and adaptive responses but also diverse metabolic functions. In this study, we analyzed the expression of host HNF-1α in relation to malaria infection and evaluated its interaction with the 5'-untranslated region of subtilisin-like protease 2 (subtilase, Sub2). Recombinant human HNF-1α expressed by a lentiviral vector (LV HNF-1α) was introduced into mice. Interestingly, differences in the activity of the 5'-untranslated region of the Pf-Sub2 promoter were detected in 293T cells, and LV HNF-1α was observed to influence promoter activity, suggesting that host HNF-1α interacts with the Sub2 gene.

Altered Left Ventricular Geometry and Torsional Mechanics in High Altitude-Induced Pulmonary Hypertension: A Three-Dimensional Echocardiographic Study.

PubMed

De Boeck, Bart W; Toma, Aurel; Kiencke, Stephanie; Dehnert, Christoph; Zügel, Stefanie; Siebenmann, Christoph; Auinger, Katja; Buser, Peter T; Maggiorini, Marco; Kaufmann, Beat A

2018-03-01

Changes in left ventricular (LV) torsion have been related to LV geometry in patients with concomitant long-standing myocardial disease or pulmonary hypertension (PH). We evaluated the effect of acute high altitude-induced isolated PH on LV geometry, volumes, systolic function, and torsional mechanics. Twenty-three volunteers were prospectively studied at low altitude and after the second (D3) and third night (D4) at high altitude (4,559 m). LV ejection fraction, multidirectional strains and torsion, LV volumes, sphericity, and eccentricity were derived by speckle-tracking on three-dimensional echocardiographic data sets. Pulmonary pressure was estimated from the transtricuspid pressure gradient (TRPG), LV preload from end-diastolic LV volume, and transmitral over mitral annular E velocity (E/e'). At high altitude, oxygen saturation decreased by 15%-20%, heart rate and cardiac index increased by 15%-20%, and TRPG increased from 21 ± 2 to 37 ± 9 mm Hg (P < .01). LV volumes, preload, ejection fraction, multidirectional strains, and sphericity remained unaffected, but diastolic (1.04 ± 0.07 to 1.09 ± 0.09 on D3/D4, P < .05) and systolic (1.00 ± 0.06 to 1.08 ± 0.1 [D3] and 1.06 ± 0.07 [D4], P < .05) eccentricity slightly increased, indicating mild septal flattening. LV torsion decreased from 2.14 ± 0.85 to 1.34 ± 0.68 (P < .05) and 1.65 ± 0.54 (P = .08) degrees/cm on D3/D4, respectively. Changes in torsion showed a weak inverse relationship to changes in systolic (r = -0.369, P = .013) and diastolic (r = -0.329, P = .032) eccentricity but not to changes in TRPG, heart rate or preload. High-altitude exposure was associated with mild septal flattening of the LV and reduced ventricular torsion at unchanged global LV function and preload, suggesting a relation between LV geometry and torsional mechanics. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Exploratory assessment of left ventricular strain–volume loops in severe aortic valve diseases

PubMed Central

Hulshof, Hugo G.; van Dijk, Arie P.; George, Keith P.; Hopman, Maria T. E.; Thijssen, Dick H. J.

2017-01-01

Key points Severe aortic valve diseases are common cardiac abnormalities that are associated with poor long‐term survival.Before any reduction in left ventricular (LV) function, the left ventricle undergoes structural remodelling under the influence of changing haemodynamic conditions.In this study, we combined temporal changes in LV structure (volume) with alterations in LV functional characteristics (strain, ԑ) into a ԑ–volume loop, in order to provide novel insight into the haemodynamic cardiac consequences of aortic valve diseases in those with preserved LV ejection fraction.We showed that our novel ԑ–volume loop and the specific loop characteristics provide additional insight into the functional and mechanical haemodynamic consequences of severe aortic valve diseases (with preserved LV ejection fraction).Finally, we showed that the ԑ–volume loop characteristics provide discriminative capacity compared with conventional measures of LV function. Abstract The purpose of this study was to examine left ventricular (LV) strain (ԑ)–volume loops to provide novel insight into the haemodynamic cardiac consequences of aortic valve stenosis (AS) and aortic valve regurgitation (AR). Twenty‐seven participants were retrospectively recruited: AR (n = 7), AS (n = 10) and control subjects (n = 10). Standard transthoracic echocardiography was used to obtain apical four‐chamber images to construct ԑ–volume relationships, which were assessed using the following parameters: early systolic ԑ (ԑ_ES); slope of ԑ–volume relationship during systole (Sslope); end‐systolic peak ԑ (peak ԑ); and diastolic uncoupling (systolic ԑ–diastolic ԑ at same volume) during early diastole (UNCOUP_ED) and late diastole (UNCOUP_LD). Receiver operating characteristic curves were used to determine the ability to detect impaired LV function. Although LV ejection fraction was comparable between groups, longitudinal peak ԑ was reduced compared with control subjects. In contrast, ԑ_ES and Sslope were lower in both pathologies compared with control subejcts (P < 0.01), but also different between AS and AR (P < 0.05). UNCOUP_ED and UNCOUP_LD were significantly higher in both patient groups compared with control subjects (P < 0.05). Receiver operating characteristic curves revealed that loop characteristics (AUC = 0.99, 1.00 and 1.00; all P < 0.01) were better able then peak ԑ (AUC = 0.75, 0.89 and 0.76; P = 0.06, <0.01 and 0.08, respectively) and LV ejection fraction (AUC = 0.56, 0.69 and 0.69; all P > 0.05) to distinguish AS vs control, AR vs control and AS vs AR groups, respectively. Temporal changes in ԑ–volume characteristics provide novel insight into the haemodynamic cardiac impact of AS and AR. Contrary to traditional measures (i.e. ejection fraction, peak ԑ), these novel measures successfully distinguish between the haemodynamic cardiac impact of AS and AR. PMID:28117492

Exploratory assessment of left ventricular strain-volume loops in severe aortic valve diseases.

PubMed

Hulshof, Hugo G; van Dijk, Arie P; George, Keith P; Hopman, Maria T E; Thijssen, Dick H J; Oxborough, David L

2017-06-15

Severe aortic valve diseases are common cardiac abnormalities that are associated with poor long-term survival. Before any reduction in left ventricular (LV) function, the left ventricle undergoes structural remodelling under the influence of changing haemodynamic conditions. In this study, we combined temporal changes in LV structure (volume) with alterations in LV functional characteristics (strain, ԑ) into a ԑ-volume loop, in order to provide novel insight into the haemodynamic cardiac consequences of aortic valve diseases in those with preserved LV ejection fraction. We showed that our novel ԑ-volume loop and the specific loop characteristics provide additional insight into the functional and mechanical haemodynamic consequences of severe aortic valve diseases (with preserved LV ejection fraction). Finally, we showed that the ԑ-volume loop characteristics provide discriminative capacity compared with conventional measures of LV function. The purpose of this study was to examine left ventricular (LV) strain (ԑ)-volume loops to provide novel insight into the haemodynamic cardiac consequences of aortic valve stenosis (AS) and aortic valve regurgitation (AR). Twenty-seven participants were retrospectively recruited: AR (n = 7), AS (n = 10) and control subjects (n = 10). Standard transthoracic echocardiography was used to obtain apical four-chamber images to construct ԑ-volume relationships, which were assessed using the following parameters: early systolic ԑ (ԑ_ES); slope of ԑ-volume relationship during systole (Sslope); end-systolic peak ԑ (peak ԑ); and diastolic uncoupling (systolic ԑ-diastolic ԑ at same volume) during early diastole (UNCOUP_ED) and late diastole (UNCOUP_LD). Receiver operating characteristic curves were used to determine the ability to detect impaired LV function. Although LV ejection fraction was comparable between groups, longitudinal peak ԑ was reduced compared with control subjects. In contrast, ԑ_ES and Sslope were lower in both pathologies compared with control subejcts (P < 0.01), but also different between AS and AR (P < 0.05). UNCOUP_ED and UNCOUP_LD were significantly higher in both patient groups compared with control subjects (P < 0.05). Receiver operating characteristic curves revealed that loop characteristics (AUC = 0.99, 1.00 and 1.00; all P < 0.01) were better able then peak ԑ (AUC = 0.75, 0.89 and 0.76; P = 0.06, <0.01 and 0.08, respectively) and LV ejection fraction (AUC = 0.56, 0.69 and 0.69; all P > 0.05) to distinguish AS vs control, AR vs control and AS vs AR groups, respectively. Temporal changes in ԑ-volume characteristics provide novel insight into the haemodynamic cardiac impact of AS and AR. Contrary to traditional measures (i.e. ejection fraction, peak ԑ), these novel measures successfully distinguish between the haemodynamic cardiac impact of AS and AR. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

Mass and Momentum Turbulent Transport Experiments with Confined Coaxial Jets

NASA Technical Reports Server (NTRS)

Johnson, B. V.; Bennett, J. C.

1981-01-01

Downstream mixing of coaxial jets discharging in an expanded duct was studied to obtain data for the evaluation and improvement of turbulent transport models currently used in a variety of computational procedures throughout the propulsion community for combustor flow modeling. Flow visualization studies showed four major shear regions occurring; a wake region immediately downstream of the inlet jet inlet duct; a shear region further downstream between the inner and annular jets; a recirculation zone; and a reattachment zone. A combination of turbulent momentum transport rate and two velocity component data were obtained from simultaneous measurements with a two color laser velocimeter (LV) system. Axial, radial and azimuthal velocities and turbulent momentum transport rate measurements in the r-z and r-theta planes were used to determine the mean value, second central moment (or rms fluctuation from mean), skewness and kurtosis for each data set probability density function (p.d.f.). A combination of turbulent mass transport rate, concentration and velocity data were obtained system. Velocity and mass transport in all three directions as well as concentration distributions were used to obtain the mean, second central moments, skewness and kurtosis for each p.d.f. These LV/LIF measurements also exposed the existence of a large region of countergradient turbulent axial mass transport in the region where the annular jet fluid was accelerating the inner jet fluid.

Two types of calmodulin play different roles in Pacific white shrimp (Litopenaeus vannamei) defenses against Vibrio parahaemolyticus and WSSV infection.

PubMed

Ji, Pei-Feng; Yao, Cui-Luan; Wang, Zhi-Yong

2011-08-01

Calmodulin (CaM) plays an important role in calcium-dependent signal transduction pathways. In the present study, two alternative splicing isoforms of CaM (named LvCaM-A and LvCaM-B) cDNA were cloned from the Pacific white shrimp, Litopenaeus vannamei. LvCaM-A was of 1101 bp, including a 5'-terminal untranslated region (UTR) of 70 bp, a 3'-terminal UTR of 581 bp and an open reading frame (ORF) of 450 bp encoding a polypeptide of 149 amino acids with a calculated molecular weight (Mw) of 17 kDa and pI of 4.41. LvCaM-B was 689 bp, including a same 5'-UTR of 70 bp, a 3'-terminal UTR of 109 bp and an ORF of 510 bp encoding a polypeptide of 169 amino acids with a calculated Mw of 19 kDa and pI of 4.36. Both LvCaM-A and LvCaM-B contained 4 conservative EF-hand motifs. Quantitative real-time reverse transcription PCR analysis revealed LvCaM-A to be expressed in most shrimp tissues, with the predominant expression in nerve and the weakest expression in heart. However, LvCaM-B expression level was much weaker than those of LvCaM-A in all the tested tissues with main expression in hepatopancreas. The expression of LvCaM-A and LvCaM-B after challenge with Vibrio parahaemolyticus and WSSV were tested in hemocytes, hepatopancreas and nerve. The results indicated that LvCaM-A and LvCaM-B transcripts could be significantly induced in hemocytes and hepatopancreas respectively by injection with V. parahaemolyticus. The highest expression of LvCaM-A was in the hemocytes with 2.3 times (at 48 h) greater expression than in the control (p < 0.05). However, sharp down-regulation of both LvCaM-A and LvCaM-B were detected in nerve after Vibrio- and WSSV injection (p < 0.05). These results suggested that CaM might play an important role in shrimp's defense against pathogenic infection. Copyright © 2011 Elsevier Ltd. All rights reserved.

Plasma tissue inhibitor of metalloproteinase-1 and matrix metalloproteinase-9: novel indicators of left ventricular remodelling and prognosis after acute myocardial infarction.

PubMed

Kelly, Dominic; Khan, Sohail Q; Thompson, Matt; Cockerill, Gillian; Ng, Leong L; Samani, Nilesh; Squire, Iain B

2008-09-01

Matrix metalloproteinase (MMP) activity is central to the development of left ventricular (LV) remodelling and dysfunction after acute myocardial infarction (AMI). We assessed the relationships with LV structure and function and outcome, of tissue inhibitors of metalloproteinase-1 (TIMP-1) and MMP-9, and compared with N-terminal pro-B-type natriuretic peptide (NTproBNP). We studied 404 patients with AMI. Primary outcome measures were the associations of TIMP-1, MMP-9, and NTproBNP with death or heart failure, and with LV dimensions, function and remodelling (ΔLVEDV, change in LV end-diastolic volume between discharge and follow-up). Cut-off concentrations for prediction of death or heart failure were identified from receiver operator characteristic (ROC) curves. In multivariable analysis, TIMP-1 and NTproBNP had predictive value for LV ejection fraction pre-discharge (TIMP-1 P = 0.023; N-BNP P = 0.007) and at follow-up (TIMP-1 P = 0.001; N-BNP P = 0.003). MMP-9, TIMP-1, and NTproBNP correlated directly with LV volumes. MMP-9 (P = 0.005) and TIMP-1 (P = 0.036), but not NTproBNP, correlated with ΔLVEDV. For the combined endpoint of death or heart failure the area under the ROC curve was 0.640 for MMP-9, 0.799 for NTproBNP and 0.811 for TIMP-1. Patients with TIMP-1 > 135 ng/mL (P < 0.001) or NTproBNP >1472 fmol/mL (P < 0.001) had increased risk of endpoint. Consideration of both NTproBNP and TIMP-1 further improved risk stratification. TIMP-1 and MMP-9 correlate with echocardiographic parameters of LV dysfunction and remodelling after AMI and may identify patients at risk of subsequent LV remodelling and adverse prognosis.

Shrimp TAB1 interacts with TAK1 and p38 and activates the host innate immune response to bacterial infection.

PubMed

Wang, Sheng; Li, Mengqiao; Yin, Bin; Li, Haoyang; Xiao, Bang; Lǚ, Kai; Huang, Zhijian; Li, Sedong; He, Jianguo; Li, Chaozheng

2017-08-01

Mammalian TAB1 has been previously identified as transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) binding protein, which functions as the activator of TAK1 and p38. This report, for the first time, identified and characterized the homolog of TAB1 in shrimp, to be specific, the homolog gene from Litopenaeus vannamei, containing a 1560-bp open reading frame (ORF) that encoded a putative protein of 519 amino acids with the conserved PP2Cc (Serine/threonine phosphatases, family 2C, catalytic) domain in N-terminal and a TAK1 binding motif in C-terminus, has been cloned and named LvTAB1. LvTAB1 was most abundant in gills and its expression could respond significantly to a series of stimuli, including LPS, Vibrio parahemolyticus and Staphylococcus aureus. Moreover, Co-immunoprecipitation (Co-IP) experiments showed that LvTAB1 could combine with LvTAK1 as well as Lvp38, two members of IMD-NF-κB/MAPK pathway, which meant LvTAB1 could have a role in regulating the activities of these kinases. Over-expression of LvTAB1 in drosophila S2 cells could improve the transcriptional levels of antimicrobial peptide genes (AMPs) such as Diptericin (Dpt), the hallmark of drosophila NF-κB activated genes, indicating its activation effect on NF-κB pathway. Furthermore, suppression of LvTAB1 expression in vivo by RNA-interference increased the sensibility of shrimps to V. parahaemolyticus infection, implying its protective role against bacterial infection. In conclusion, these results provide some insight into the function of LvTAB1 during bacterial infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

A mathematical model for active contraction in healthy and failing myocytes and left ventricles.

PubMed

Cai, Li; Wang, Yongheng; Gao, Hao; Li, Yiqiang; Luo, Xiaoyu

2017-01-01

Cardiovascular disease is one of the leading causes of death worldwide, in particular myocardial dysfunction, which may lead to heart failure eventually. Understanding the electro-mechanics of the heart will help in developing more effective clinical treatments. In this paper, we present a multi-scale electro-mechanics model of the left ventricle (LV). The Holzapfel-Ogden constitutive law was used to describe the passive myocardial response in tissue level, a modified Grandi-Pasqualini-Bers model was adopted to model calcium dynamics in individual myocytes, and the active tension was described using the Niederer-Hunter-Smith myofilament model. We first studied the electro-mechanics coupling in a single myocyte in the healthy and diseased left ventricle, and then the single cell model was embedded in a dynamic LV model to investigate the compensation mechanism of LV pump function due to myocardial dysfunction caused by abnormality in cellular calcium dynamics. The multi-scale LV model was solved using an in-house developed hybrid immersed boundary method with finite element extension. The predictions of the healthy LV model agreed well with the clinical measurements and other studies, and likewise, the results in the failing states were also consistent with clinical observations. In particular, we found that a low level of intracellular Ca2+ transient in myocytes can result in LV pump function failure even with increased myocardial contractility, decreased systolic blood pressure, and increased diastolic filling pressure, even though they will increase LV stroke volume. Our work suggested that treatments targeted at increased contractility and lowering the systolic blood pressure alone are not sufficient in preventing LV pump dysfunction, restoring a balanced physiological Ca2+ handling mechanism is necessary.

Rheumatoid Arthritis is Independently Associated with Increased Left Ventricular Mass but not Reduced Ejection Fraction

PubMed Central

Rudominer, Rebecca L.; Roman, Mary J.; Devereux, Richard B.; Paget, Stephen A.; Schwartz, Joseph E.; Lockshin, Michael D.; Crow, Mary K.; Sammaritano, Lisa; Levine, Daniel M.; Salmon, Jane E.

2008-01-01

Background Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with premature atherosclerosis, vascular stiffening, and heart failure. Whether RA is associated with underlying structural and functional abnormalities of the left ventricle (LV) is poorly understood. Methods and Results 89 patients with RA without clinical cardiovascular disease and 89 healthy matched controls underwent echocardiography, carotid ultrasonography, and radial tonometry to measure arterial stiffness. RA patients and controls were similar in body size, hypertension and diabetes status, and cholesterol. LV diastolic diameter (4.92 vs. 4.64 cm, p <0.001), mass (136.9 vs. 121.7 g, p = 0.001 or 36.5 vs. 32.9 g/m 2.7, p = 0.01), ejection fraction (EF) (71% vs. 67%, p <0.001), and prevalence of LV hypertrophy (LVH) (18% vs. 6.7%, p = 0.023) were all higher among RA patients. In multivariate analysis, presence of RA (p = 0.004) was an independent correlate of LV mass. Furthermore, RA was independently associated with the presence of LVH (OR 4.14, [95% CI 1.24-13.80; p=0.021]). Among RA patients, age at diagnosis and disease duration were independently related to LV mass. RA patients with LVH were older and had higher systolic pressure, damage index score, C-reactive protein, homocysteine and arterial stiffness index compared to those without LVH. Conclusion RA is associated with increased LV mass. Disease duration is independently related to increased LV mass, suggesting a pathophysiological link between chronic inflammation and LVH. In contrast, LV systolic function is preserved in RA patients indicating that systolic dysfunction is not an intrinsic feature of RA. PMID:19116901

Disruption of Desmin-Mitochondrial Architecture in Patients with Regurgitant Mitral Valves and Preserved Ventricular Function

PubMed Central

Soorappan, Rajasekaran Namakkal; Ahmad, Shama; Mariappan, Nithya; Litovsky, Silvio; Gupta, Himanshu; Lloyd, Steven G; Denney, Thomas S; Powell, Pamela Cox; Aban, Inmaculada; Collawn, James; Davies, James E; McGiffin, David C; Dell’Italia, Louis J

2016-01-01

Objective Recent studies have demonstrated improved outcomes in patients receiving early surgery for degenerative mitral valvular regurgitation (MR) rather than adhering to conventional guidelines for surgical intervention. However, studies providing a mechanistic basis for these findings are limited. Methods Left ventricular (LV) myocardium from 22 patients undergoing mitral valve repair for Class I indications was evaluated for desmin, the voltage-dependent anion channel, αβ-crystallin, and α, β unsaturated aldehyde 4-hydroxynonelal by fluorescence microscopy and in 6 normal control LV autopsy specimens. Cardiomyocyte ultrastructure was examined by transmission electron microscopy. Magnetic resonance imaging with tissue tagging was performed in 55 normal subjects and 22 MR patients pre- and 6 months post-mitral valve repair. Results LV end-diastolic volume was 1.5-fold (p<0.0001) higher and LV mass to volume ratio was lower in MR (p=0.004) vs. normal and improvement six months after mitral valve surgery. However, LV ejection fraction decreased from 65 ± 7 to 52 ± 9% (p<0.0001) and LV circumferential (p<0.0001) and longitudinal strain decreased significantly below normal values (p=0.002) post-surgery. MR hearts had a 53% decrease in desmin (p<0.0001) and a 2.6-fold increase in desmin aggregates (p<0.0001) vs. normal along with significant, intense perinuclear staining of α, β unsaturated aldehyde 4-hydroxynonelal in areas of mitochondrial breakdown and clustering. Transmission electron microscopy demonstrated numerous electron dense deposits, myofibrillar loss, Z-line abnormalities and extensive granulofilamentous debris identified as desmin positive by immunogold transmission electron microscopy. Conclusion Despite well-preserved preoperative LV ejection fraction, severe oxidative stress and disruption of cardiomyocyte desmin-mitochondrial sarcomeric architecture may explain post-operative LV functional decline and further supports the move toward earlier surgical intervention. PMID:27464577

Differentiating Electromechanical From Non-Electrical Substrates of Mechanical Discoordination to Identify Responders to Cardiac Resynchronization Therapy.

PubMed

Lumens, Joost; Tayal, Bhupendar; Walmsley, John; Delgado-Montero, Antonia; Huntjens, Peter R; Schwartzman, David; Althouse, Andrew D; Delhaas, Tammo; Prinzen, Frits W; Gorcsan, John

2015-09-01

Left ventricular (LV) mechanical discoordination, often referred to as dyssynchrony, is often observed in patients with heart failure regardless of QRS duration. We hypothesized that different myocardial substrates for LV mechanical discoordination exist from (1) electromechanical activation delay, (2) regional differences in contractility, or (3) regional scar and that we could differentiate electromechanical substrates responsive to cardiac resynchronization therapy (CRT) from unresponsive non-electrical substrates. First, we used computer simulations to characterize mechanical discoordination patterns arising from electromechanical and non-electrical substrates and accordingly devise the novel systolic stretch index (SSI), as the sum of posterolateral systolic prestretch and septal systolic rebound stretch. Second, 191 patients with heart failure (QRS duration ≥120 ms; LV ejection fraction ≤35%) had baseline SSI quantified by automated echocardiographic radial strain analysis. Patients with SSI≥9.7% had significantly less heart failure hospitalizations or deaths 2 years after CRT (hazard ratio, 0.32; 95% confidence interval, 0.19-0.53; P<0.001) and less deaths, transplants, or LV assist devices (hazard ratio, 0.28; 95% confidence interval, 0.15-0.55; P<0.001). Furthermore, in a subgroup of 113 patients with intermediate electrocardiographic criteria (QRS duration of 120-149 ms or non-left bundle branch block), SSI≥9.7% was independently associated with significantly less heart failure hospitalizations or deaths (hazard ratio, 0.41; 95% confidence interval, 0.23-0.79; P=0.004) and less deaths, transplants, or LV assist devices (hazard ratio, 0.27; 95% confidence interval, 0.12-0.60; P=0.001). Computer simulations differentiated patterns of LV mechanical discoordination caused by electromechanical substrates responsive to CRT from those related to regional hypocontractility or scar unresponsive to CRT. The novel SSI identified patients who benefited more favorably from CRT, including those with intermediate electrocardiographic criteria, where CRT response is less certain by ECG alone. © 2015 American Heart Association, Inc.

Marked regional left ventricular heterogeneity in hypertensive left ventricular hypertrophy patients: a losartan intervention for endpoint reduction in hypertension (LIFE) cardiovascular magnetic resonance and echocardiographic substudy.

PubMed

Biederman, Robert W W; Doyle, Mark; Young, Alistair A; Devereux, Richard B; Kortright, Eduardo; Perry, Gilbert; Bella, Jonathan N; Oparil, Suzanne; Calhoun, David; Pohost, Gerald M; Dell'Italia, Louis J

2008-08-01

Concentric hypertensive left ventricular (LV) hypertrophy is presumed to be a symmetrical process. Using MRI-derived intramyocardial strain, we sought to determine whether segmental deformation was also symmetrical, as suggested by echocardiography. High echocardiographic LV relative wall thickness in hypertensive LV hypertrophy allows preserved endocardial excursion despite depressed LV midwall shortening (MWS). Depressed MWS is an adverse prognostic indicator, but whether this is related to global or regional myocardial depression is unknown. We prospectively compared MWS derived from linear echocardiographic dimensions with MR strain(in) in septal and posterior locations in 27 subjects with ECG LV hypertrophy in the Losartan Intervention for Endpoint Reduction in Hypertension Study. Although MRI-derived mass was higher in patients than in normal control subjects (124.0+/-38.6 versus 60.5+/-13.2g/m(2); P<0.001), fractional shortening (30+/-5% versus 33+/-3%) and end-systolic stress (175+/-22 versus 146+/-28 g/cm(2)) did not differ between groups. However, mean MR(in) was decreased in patients versus normal control subjects (13.9+/-6.8% versus 22.4+/-3.5%), as was echo MWS (13.4+/-2.8% versus 18.2+/-1.4%; both P<0.001). For patients versus normal control subjects, posterior wall(in) was not different (17.8+/-7.1% versus 21.6+/-4.0%), whereas septal(in) was markedly depressed (10.1+/-6.6% versus 23.2+/-3.4%; P<0.001). Although global MWS by echocardiography or MRI is depressed in hypertensive LV hypertrophy, MRI tissue tagging demonstrates substantial regional intramyocardial strain(in) heterogeneity, with most severely depressed strain patterns in the septum. Although posterior wall 2D principal strain was inversely related to radius of curvature, septal strain was not, suggesting that factors other than afterload are responsible for pronounced myocardial strain heterogeneity in concentric hypertrophy.

Comparison of echocardiographic and cardiac magnetic resonance imaging measurements of functional single ventricular volumes, mass, and ejection fraction (from the Pediatric Heart Network Fontan Cross-Sectional Study).

PubMed

Margossian, Renee; Schwartz, Marcy L; Prakash, Ashwin; Wruck, Lisa; Colan, Steven D; Atz, Andrew M; Bradley, Timothy J; Fogel, Mark A; Hurwitz, Lynne M; Marcus, Edward; Powell, Andrew J; Printz, Beth F; Puchalski, Michael D; Rychik, Jack; Shirali, Girish; Williams, Richard; Yoo, Shi-Joon; Geva, Tal

2009-08-01

Assessment of the size and function of a functional single ventricle (FSV) is a key element in the management of patients after the Fontan procedure. Measurement variability of ventricular mass, volume, and ejection fraction (EF) among observers by echocardiography and cardiac magnetic resonance imaging (CMR) and their reproducibility among readers in these patients have not been described. From the 546 patients enrolled in the Pediatric Heart Network Fontan Cross-Sectional Study (mean age 11.9 +/- 3.4 years), 100 echocardiograms and 50 CMR studies were assessed for measurement reproducibility; 124 subjects with paired studies were selected for comparison between modalities. Interobserver agreement for qualitative grading of ventricular function by echocardiography was modest for left ventricular (LV) morphology (kappa = 0.42) and weak for right ventricular (RV) morphology (kappa = 0.12). For quantitative assessment, high intraclass correlation coefficients were found for echocardiographic interobserver agreement (LV 0.87 to 0.92, RV 0.82 to 0.85) of systolic and diastolic volumes, respectively. In contrast, intraclass correlation coefficients for LV and RV mass were moderate (LV 0.78, RV 0.72). The corresponding intraclass correlation coefficients by CMR were high (LV 0.96, RV 0.85). Volumes by echocardiography averaged 70% of CMR values. Interobserver reproducibility for the EF was similar for the 2 modalities. Although the absolute mean difference between modalities for the EF was small (<2%), 95% limits of agreement were wide. In conclusion, agreement between observers of qualitative FSV function by echocardiography is modest. Measurements of FSV volume by 2-dimensional echocardiography underestimate CMR measurements, but their reproducibility is high. Echocardiographic and CMR measurements of FSV EF demonstrate similar interobserver reproducibility, whereas measurements of FSV mass and LV diastolic volume are more reproducible by CMR.

Early myocardial dysfunction in streptozotocin-induced diabetic mice: a study using in vivo magnetic resonance imaging (MRI)

PubMed Central

Yu, Xichun; Tesiram, Yasvir A; Towner, Rheal A; Abbott, Andrew; Patterson, Eugene; Huang, Shijun; Garrett, Marion W; Chandrasekaran, Suresh; Matsuzaki, Satoshi; Szweda, Luke I; Gordon, Brian E; Kem, David C

2007-01-01

Background Diabetes is associated with a cardiomyopathy that is independent of coronary artery disease or hypertension. In the present study we used in vivo magnetic resonance imaging (MRI) and echocardiographic techniques to examine and characterize early changes in myocardial function in a mouse model of type 1 diabetes. Methods Diabetes was induced in 8-week old C57BL/6 mice with two intraperitoneal injections of streptozotocin. The blood glucose levels were maintained at 19–25 mmol/l using intermittent low dosages of long acting insulin glargine. MRI and echocardiography were performed at 4 weeks of diabetes (age of 12 weeks) in diabetic mice and age-matched controls. Results After 4 weeks of hyperglycemia one marker of mitochondrial function, NADH oxidase activity, was decreased to 50% of control animals. MRI studies of diabetic mice at 4 weeks demonstrated significant deficits in myocardial morphology and functionality including: a decreased left ventricular (LV) wall thickness, an increased LV end-systolic diameter and volume, a diminished LV ejection fraction and cardiac output, a decreased LV circumferential shortening, and decreased LV peak ejection and filling rates. M-mode echocardiographic and Doppler flow studies of diabetic mice at 4 weeks showed a decreased wall thickening and increased E/A ratio, supporting both systolic and diastolic dysfunction. Conclusion Our study demonstrates that MRI interrogation can identify the onset of diabetic cardiomyopathy in mice with its impaired functional capacity and altered morphology. The MRI technique will lend itself to repetitive study of early changes in cardiac function in small animal models of diabetic cardiomyopathy. PMID:17309798

Best anesthetics for assessing left ventricular systolic function by echocardiography in mice

PubMed Central

Pachon, Ronald E.; Scharf, Bruce A.; Vatner, Dorothy E.

2015-01-01

Our review of the literature of the major cardiovascular journals for the past three years showed that for all studies using anesthesia for mouse echocardiography, the predominant anesthetic was isoflurane, which was used in 76% of the studies. The goal of this investigation was to determine if isoflurane is indeed the best anesthetic. Accordingly, we compared isoflurane with 2,2,2-tribromoethanol (Avertin), ketamine-xylazine, and ketamine on different days in the same 14 mice, also studied in the conscious state without anesthesia. A randomized crossover study design was employed to compare the effects on left ventricular (LV) systolic function and heart rate of the four different anesthetic agents assessed by transthoracic echocardiography. As expected, each anesthetic depressed LV ejection fraction and heart rate when compared with values in conscious mice. Surprisingly, isoflurane was not the best, but actually second to last in maintaining normal LV function and heart rate. The anesthetic with the least effect on LV function and heart rate was ketamine alone at a dose of 150 mg/kg, followed by Avertin at 290 mg/kg, isoflurane at 3% induction and 1 to 2% maintenance, and lastly ketamine-xylazine at 100 and 10 mg/kg, respectively. In summary, these results indicate that ketamine alone exerts the least depressant effects on LV function and heart rate, with Avertin second, suggesting that these anesthetics should be used when it is not feasible to study the animals in the conscious state as opposed to the most commonly used anesthetic, isoflurane. PMID:25862835

Best anesthetics for assessing left ventricular systolic function by echocardiography in mice.

PubMed

Pachon, Ronald E; Scharf, Bruce A; Vatner, Dorothy E; Vatner, Stephen F

2015-06-15

Our review of the literature of the major cardiovascular journals for the past three years showed that for all studies using anesthesia for mouse echocardiography, the predominant anesthetic was isoflurane, which was used in 76% of the studies. The goal of this investigation was to determine if isoflurane is indeed the best anesthetic. Accordingly, we compared isoflurane with 2,2,2-tribromoethanol (Avertin), ketamine-xylazine, and ketamine on different days in the same 14 mice, also studied in the conscious state without anesthesia. A randomized crossover study design was employed to compare the effects on left ventricular (LV) systolic function and heart rate of the four different anesthetic agents assessed by transthoracic echocardiography. As expected, each anesthetic depressed LV ejection fraction and heart rate when compared with values in conscious mice. Surprisingly, isoflurane was not the best, but actually second to last in maintaining normal LV function and heart rate. The anesthetic with the least effect on LV function and heart rate was ketamine alone at a dose of 150 mg/kg, followed by Avertin at 290 mg/kg, isoflurane at 3% induction and 1 to 2% maintenance, and lastly ketamine-xylazine at 100 and 10 mg/kg, respectively. In summary, these results indicate that ketamine alone exerts the least depressant effects on LV function and heart rate, with Avertin second, suggesting that these anesthetics should be used when it is not feasible to study the animals in the conscious state as opposed to the most commonly used anesthetic, isoflurane. Copyright © 2015 the American Physiological Society.

Effects of testosterone and nandrolone on cardiac function: a randomized, placebo-controlled study.

PubMed

Chung, T; Kelleher, S; Liu, P Y; Conway, A J; Kritharides, L; Handelsman, D J

2007-02-01

Androgens have striking effects on skeletal muscle, but the effects on human cardiac muscle function are not well defined, neither has the role of metabolic activation (aromatization, 5alpha reduction) of testosterone on cardiac muscle been directly studied. To assess the effects of testosterone and nandrolone, a non-amplifiable and non-aromatizable pure androgen, on cardiac muscle function in healthy young men. Double-blind, randomized, placebo-controlled, three-arm parallel group clinical trial. Ambulatory care research centre. Healthy young men randomized into three groups of 10 men. Weekly intramuscular injections of testosterone (200 mg mixed esters), nandrolone (200 mg nandrolone decanoate) or matching (2 ml arachis oil vehicle) placebo for 4 weeks. Comprehensive measures of cardiac muscle function involving transthoracic cardiac echocardiography measuring myocardial tissue velocity, peak systolic strain and strain rates, and bioimpedance measurement of cardiac output and systematic vascular resistance. Left ventricular (LV) function (LV ejection fraction, LV modified TEI index), right ventricular (RV) function (ejection area, tricuspid annular systolic planar motion, RV modified TEI index) as well as cardiac afterload (mean arterial pressure, systemic vascular resistance) and overall cardiac contractility (stroke volume, cardiac output) were within age- and gender-specific reference ranges and were not significantly (P < 0.05) altered by either androgen or placebo over 4 weeks of treatment. Minor changes remaining within normal range were observed solely within the testosterone group for: increased LV end-systolic diameter (30 +/- 7 vs. 33 +/- 5 mm, P = 0.04) and RV end-systolic area (12.8 +/- 1.3 vs. 14.6 +/- 3.3 cm(2), P = 0.04), reduced LV diastolic septal velocity (Em, 9.5 +/- 2.6 vs. 8.7 +/- 2.0 cm/s, P = 0.006), increased LV filling pressure (E/Em ratio, 7.1 +/- 1.6 vs. 8.3 +/- 1.8, P = 0.02) and shortened PR interval on the electrocardiogram (167 +/- 13 vs. 154 +/- 12, P = 0.03). Four weeks of treatment with testosterone or nandrolone had no beneficial or adverse effects compared with placebo on cardiac function in healthy young men.

Cardiovascular Effects of 1 Year of Progressive and Vigorous Exercise Training in Previously Sedentary Individuals Older Than 65 Years of Age

PubMed Central

Fujimoto, Naoki; Prasad, Anand; Hastings, Jeffrey L.; Arbab-Zadeh, Armin; Bhella, Paul S.; Shibata, Shigeki; Palmer, Dean; Levine, Benjamin D.

2013-01-01

Background Healthy but sedentary aging leads to cardiovascular stiffening, whereas life-long endurance training preserves left ventricular (LV) compliance. However, it is unknown whether exercise training started later in life can reverse the effects of sedentary behavior on the heart. Methods and Results Twelve sedentary seniors and 12 Masters athletes were thoroughly screened for comorbidities. Subjects underwent invasive hemodynamic measurements with pulmonary artery catheterization to define Starling and LV pressure-volume curves; secondary functional outcomes included Doppler echocardiography, magnetic resonance imaging assessment of cardiac morphology, arterial stiffness (total aortic compliance and arterial elastance), and maximal exercise testing. Nine of 12 sedentary seniors (70.6±3 years; 6 male, 3 female) completed 1 year of endurance training followed by repeat measurements. Pulmonary capillary wedge pressures and LV end-diastolic volumes were measured at baseline, during decreased cardiac filling with lower-body negative pressure, and increased filling with saline infusion. LV compliance was assessed by the slope of the pressure-volume curve. Before training, V̇O2max, LV mass, LV end-diastolic volume, and stroke volume were significantly smaller and the LV was less compliant in sedentary seniors than Masters athletes. One year of exercise training had little effect on cardiac compliance. However, it reduced arterial elastance and improved V̇O2 max by 19% (22.8±3.4 versus 27.2± 4.3 mL/kg/mL; P<0.001). LV mass increased (10%, 64.5±7.9 versus 71.2±12.3 g/m2; P=0.037) with no change in the mass-volume ratio. Conclusions Although 1 year of vigorous exercise training did not appear to favorably reverse cardiac stiffening in sedentary seniors, it nonetheless induced physiological LV remodeling and imparted favorable effects on arterial function and aerobic exercise capacity. PMID:20956204

Mitral annular longitudinal function preservation after mitral valve repair: the MARTE study.

PubMed

Lisi, M; Ballo, P; Cameli, M; Gandolfo, F; Galderisi, M; Chiavarelli, M; Henein, M Y; Mondillo, S

2012-05-31

In patients with chronic mitral regurgitation (MR), undergoing surgical mitral valve repair, current Guidelines only recommend standard echocardiographic indices i.e. left ventricular (LV) ejection fraction (EF), and LV end-systolic and end-diastolic diameters as preoperative variables. However LV EF is often preserved until advanced stages of the valve disease. Aim of this study was to evaluate changes in LV systolic longitudinal function, 3 months after mitral valve repair in patients with chronic degenerative MR and normal preoperative EF. We measured M-mode mitral lateral annulus systolic excursion (MAPSE) and Tissue Doppler (TD) peak systolic annular velocity (S(m)) in 31 patients with moderate to severe MR and normal EF (59.9 ± 4.7%) candidates for mitral valve repair, preoperatively and 3 months after surgery. After mitral valve repair, S(m) increased from 7.8 ± 1.4 to 9.6 ± 2.2 cm/s (p<0.0001) and MAPSE increased from 1.33 ± 0.26 to 1.55 ± 0.25 cm (p=0.0013). EF decreased from 59.9 ± 4.7 to 51.3 ± 5.9% (p<0.0001). As expected, LV diameters and volumes, wall thicknesses, midwall fractional shortening (mFS), and left atrial (LA) size were all reduced after surgery. This study suggests that assessment of LV long axis systolic velocity and amplitude of excursion by echocardiography is more sensitive than simple determination of EF for revealing the beneficial impact of MR surgery on overall systolic function. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Coincidence of moderately elevated N-terminal pro-B-type natriuretic peptide, endothelial progenitor cells deficiency and propensity to exercise-induced myocardial ischemia in stable angina.

PubMed

Surdacki, Andrzej; Marewicz, Ewa; Rakowski, Tomasz; Szumańska, Monika; Szastak, Grzegorz; Pryjma, Juliusz; Dubiel, Jacek S

2010-01-01

To assess endothelial progenitor cells (EPC) counts, a novel prognostic marker, in relation to classical adverse outcome predictors - N-terminal pro-B-type natriuretic peptide (NT-proBNP), impaired left ventricular (LV) relaxation and exercise-induced ischemia - in stable coronary artery disease (CAD) with preserved LV systolic function. We studied 30 non-diabetic men with one-vessel CAD, LV ejection fraction 60% and normal LV diastolic function (n=16) or impaired LV relaxation (by ultrasound including tissue Doppler) (n=14), and 14 non-CAD controls matched for risk profile and medication. CD34+/kinase-insert domain receptor (KDR)+ cells (CD34+/KDR+ cells), a leukocytes subpopulation enriched for EPC, were enumerated by flow cytometry. CAD patients with abnormal LV relaxation exhibited significantly elevated NT-proBNP and decreased CD34+/KDR+ cells vs. CAD with regular diastolic function and non-CAD controls. An inverse NT-proBNP-CD34+/KDR+ cells relationship was precipitated by the clustering of high resting NT-proBNP and low CD34+/KDR+ cells in the subjects with a lower Duke treadmill score. Propensity to symptomatic exertional ischemia may underlie the coincidence of moderately elevated NT-proBNP and EPC deficiency in stable angina. Additionally, chronic subclinical ischemia can also be involved in these associations. These might result from BNP overexpression in the ischemic myocardium and a hypothetical exhaustion of the bone marrow capacity to mobilize EPC at multiple ischemic episodes, thus contributing to NT-proBNP prognostic effect irrespective of hemodynamic factors.

Comparative study of diastolic filling under varying left ventricular wall stiffness

NASA Astrophysics Data System (ADS)

Mekala, Pritam; Santhanakrishnan, Arvind

2014-11-01

Pathological remodeling of the human cardiac left ventricle (LV) is observed in hypertensive heart failure as a result of pressure overload. Myocardial stiffening occurs in these patients prior to chronic maladaptive changes, resulting in increased LV wall stiffness. The goal of this study was to investigate the change in intraventricular filling fluid dynamics inside a physical model of the LV as a function of wall stiffness. Three LV models of varying wall stiffness were incorporated into an in vitro flow circuit driven by a programmable piston pump. Windkessel elements were used to tune the inflow and systemic pressure in the model with least stiffness to match healthy conditions. Models with stiffer walls were comparatively tested maintaining circuit compliance, resistance and pump amplitude constant. 2D phase-locked PIV measurements along the central plane showed that with increase in wall stiffness, the peak velocity and cardiac output inside the LV decreased. Further, inflow vortex ring propagation toward the LV apex was reduced with increasing stiffness. The above findings indicate the importance of considering LV wall relaxation characteristics in pathological studies of filling fluid dynamics.

Global stability and quadratic Hamiltonian structure in Lotka-Volterra and quasi-polynomial systems

NASA Astrophysics Data System (ADS)

Szederkényi, Gábor; Hangos, Katalin M.

2004-04-01

We show that the global stability of quasi-polynomial (QP) and Lotka-Volterra (LV) systems with the well-known logarithmic Lyapunov function is equivalent to the existence of a local generalized dissipative Hamiltonian description of the LV system with a diagonal quadratic form as a Hamiltonian function. The Hamiltonian function can be calculated and the quadratic dissipativity neighborhood of the origin can be estimated by solving linear matrix inequalities.

And the beat goes on: maintained cardiovascular function during aging in the longest-lived rodent, the naked mole-rat

PubMed Central

Grimes, Kelly M.; Reddy, Anilkumar K.; Lindsey, Merry L.

2014-01-01

The naked mole-rat (NMR) is the longest-lived rodent known, with a maximum lifespan potential (MLSP) of >31 years. Despite such extreme longevity, these animals display attenuation of many age-associated diseases and functional changes until the last quartile of their MLSP. We questioned if such abilities would extend to cardiovascular function and structure in this species. To test this, we assessed cardiac functional reserve, ventricular morphology, and arterial stiffening in NMRs ranging from 2 to 24 years of age. Dobutamine echocardiography (3 μg/g ip) revealed no age-associated changes in left ventricular (LV) function either at baseline or with exercise-like stress. Baseline and dobutamine-induced LV pressure parameters also did not change. Thus the NMR, unlike other mammals, maintains cardiac reserve with age. NMRs showed no cardiac hypertrophy, evidenced by no increase in cardiomyocyte cross-sectional area or LV dimensions with age. Age-associated arterial stiffening does not occur since there are no changes in aortic blood pressures or pulse-wave velocity. Only LV interstitial collagen deposition increased 2.5-fold from young to old NMRs (P < 0.01). However, its effect on LV diastolic function is likely minor since NMRs experience attenuated age-related increases in diastolic dysfunction in comparison with other species. Overall, these findings conform to the negligible senescence phenotype, as NMRs largely stave off cardiovascular changes for at least 75% of their MLSP. This suggests that using a comparative strategy to find factors that change with age in other mammals but not NMRs could provide novel targets to slow or prevent cardiovascular aging in humans. PMID:24906918

Association of Weight and Body Composition on Cardiac Structure and Function in the ARIC Study (Atherosclerosis Risk in Communities).

PubMed

Bello, Natalie A; Cheng, Susan; Claggett, Brian; Shah, Amil M; Ndumele, Chiadi E; Roca, Gabriela Querejeta; Santos, Angela B S; Gupta, Deepak; Vardeny, Orly; Aguilar, David; Folsom, Aaron R; Butler, Kenneth R; Kitzman, Dalane W; Coresh, Josef; Solomon, Scott D

2016-08-01

Obesity increases cardiovascular risk. However, the extent to which various measures of body composition are associated with abnormalities in cardiac structure and function, independent of comorbidities commonly affecting obese individuals, is not clear. This study sought to examine the relationship between body mass index, waist circumference, and percent body fat with conventional and advanced measures of cardiac structure and function. We studied 4343 participants of the ARIC study (Atherosclerosis Risk in Communities) who were aged 69 to 82 years, free of coronary heart disease and heart failure, and underwent comprehensive echocardiography. Increasing body mass index, waist circumference, and body fat were associated with greater left ventricular (LV) mass and left atrial volume indexed to height(2.7) in both men and women (P<0.001). In women, all 3 measures were associated with abnormal LV geometry, and increasing waist circumference and body fat were associated with worse global longitudinal strain, a measure of LV systolic function. In both sexes, increasing body mass index was associated with greater right ventricular end-diastolic area and worse right ventricular fractional area change (P≤0.001). We observed similar associations for both waist circumference and percent body fat. In a large, biracial cohort of older adults free of clinically overt coronary heart disease or heart failure, obesity was associated with subclinical abnormalities in cardiac structure in both men and women and with adverse LV remodeling and impaired LV systolic function in women. These data highlight the association of obesity and subclinical abnormalities of cardiac structure and function, particularly in women. © 2016 American Heart Association, Inc.

Correlation between T2* cardiovascular magnetic resonance with left ventricular function and mass in adolescent and adult major thalassemia patients with iron overload.

PubMed

Djer, Mulyadi M; Anggriawan, Shirley L; Gatot, Djajadiman; Amalia, Pustika; Sastroasmoro, Sudigdo; Widjaja, Patricia

2013-10-01

to assess for a correlation between T2*CMR with LV function and mass in thalassemic patients with iron overload. a cross-sectional study on thalassemic patients was conducted between July and September 2010 at Cipto Mangunkusumo and Premier Hospitals, Jakarta, Indonesia. Clinical examinations, review of medical charts, electrocardiography, echocardiography, and T2*CMR were performed. Cardiac siderosis was measured by T2*CMR conduction time. Left ventricle diastolic and systolic functions, as well as LV mass index were measured using echocardiography. Correlations between T2*CMR and echocardiography findings, as well as serum ferritin were determined using Pearson's and Spearman's tests. thirty patients aged 13-41 years were enrolled, of whom two-thirds had -thalassemia major and one-third had HbE/-thalassemia. Diastolic dysfunction was identified in 8 patients, whereas systolic function was normal in all patients. Increased LV mass index was found in 3 patients. T2*CMR conduction times ranged from 8.98 to 55.04 ms and a value below 20 ms was demonstrated in 14 patients. There was a statistically significant moderate positive correlation of T2*CMR conduction time with E/A ratio (r = 0.471, P = 0.009), but no correlation was found with LV mass index (r=0.097, P=0.608). A moderate negative correlation was found between T2*CMR and serum ferritin (r = -0.514, P = 0.004), while a moderate negative correlation was found between serum ferritin and E/A ratio (r = -0.425, P = 0.019). T2*CMR myocardial conduction time has a moderate positive correlation with diastolic function, moderate negative correlation with serum ferritin, but not with LV mass index and systolic function.

Distribution of late gadolinium enhancement in various types of cardiomyopathies: Significance in differential diagnosis, clinical features and prognosis.

PubMed

Satoh, Hiroshi; Sano, Makoto; Suwa, Kenichiro; Saitoh, Takeji; Nobuhara, Mamoru; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Hayashi, Hideharu

2014-07-26

The recent development of cardiac magnetic resonance (CMR) techniques has allowed detailed analyses of cardiac function and tissue characterization with high spatial resolution. We review characteristic CMR features in ischemic and non-ischemic cardiomyopathies (ICM and NICM), especially in terms of the location and distribution of late gadolinium enhancement (LGE). CMR in ICM shows segmental wall motion abnormalities or wall thinning in a particular coronary arterial territory, and the subendocardial or transmural LGE. LGE in NICM generally does not correspond to any particular coronary artery distribution and is located mostly in the mid-wall to subepicardial layer. The analysis of LGE distribution is valuable to differentiate NICM with diffusely impaired systolic function, including dilated cardiomyopathy, end-stage hypertrophic cardiomyopathy (HCM), cardiac sarcoidosis, and myocarditis, and those with diffuse left ventricular (LV) hypertrophy including HCM, cardiac amyloidosis and Anderson-Fabry disease. A transient low signal intensity LGE in regions of severe LV dysfunction is a particular feature of stress cardiomyopathy. In arrhythmogenic right ventricular cardiomyopathy/dysplasia, an enhancement of right ventricular (RV) wall with functional and morphological changes of RV becomes apparent. Finally, the analyses of LGE distribution have potentials to predict cardiac outcomes and response to treatments.

Arrhythmogenic drugs can amplify spatial heterogeneities in the electrical restitution in perfused guinea-pig heart: An evidence from assessments of monophasic action potential durations and JT intervals

PubMed Central

2018-01-01

Non-uniform shortening of the action potential duration (APD90) in different myocardial regions upon heart rate acceleration can set abnormal repolarization gradients and promote arrhythmia. This study examined whether spatial heterogeneities in APD90 restitution can be amplified by drugs with clinically proved proarrhythmic potential (dofetilide, quinidine, procainamide, and flecainide) and, if so, whether these effects can translate to the appropriate changes of the ECG metrics of ventricular repolarization, such as JT intervals. In isolated, perfused guinea-pig heart preparations, monophasic action potentials and volume-conducted ECG were recorded at progressively increased pacing rates. The APD90 measured at distinct ventricular sites, as well as the JTpeak and JTend values were plotted as a function of preceding diastolic interval, and the maximum slopes of the restitution curves were determined at baseline and upon drug administration. Dofetilide, quinidine, and procainamide reverse rate-dependently prolonged APD90 and steepened the restitution curve, with effects being greater at the endocardium than epicardium, and in the right ventricular (RV) vs. the left ventricular (LV) chamber. The restitution slope was increased to a greater extent for the JTend vs. the JTpeak interval. In contrast, flecainide reduced the APD90 restitution slope at LV epicardium without producing effect at LV endocardium and RV epicardium, and reduced the JTpeak restitution slope without changing the JTend restitution. Nevertheless, with all agents, these effects translated to the amplified epicardial-to-endocardial and the LV-to-RV non-uniformities in APD90 restitution, paralleled by the increased JTend vs. JTpeak difference in the restitution slope. In summary, these findings suggest that arrhythmic drug profiles are partly attributable to the accentuated regional heterogeneities in APD90 restitution, which can be indirectly determined through ECG assessments of the JTend vs. JTpeak dynamics at variable pacing rates. PMID:29352276

Arrhythmogenic drugs can amplify spatial heterogeneities in the electrical restitution in perfused guinea-pig heart: An evidence from assessments of monophasic action potential durations and JT intervals.

PubMed

Osadchii, Oleg E

2018-01-01

Non-uniform shortening of the action potential duration (APD90) in different myocardial regions upon heart rate acceleration can set abnormal repolarization gradients and promote arrhythmia. This study examined whether spatial heterogeneities in APD90 restitution can be amplified by drugs with clinically proved proarrhythmic potential (dofetilide, quinidine, procainamide, and flecainide) and, if so, whether these effects can translate to the appropriate changes of the ECG metrics of ventricular repolarization, such as JT intervals. In isolated, perfused guinea-pig heart preparations, monophasic action potentials and volume-conducted ECG were recorded at progressively increased pacing rates. The APD90 measured at distinct ventricular sites, as well as the JTpeak and JTend values were plotted as a function of preceding diastolic interval, and the maximum slopes of the restitution curves were determined at baseline and upon drug administration. Dofetilide, quinidine, and procainamide reverse rate-dependently prolonged APD90 and steepened the restitution curve, with effects being greater at the endocardium than epicardium, and in the right ventricular (RV) vs. the left ventricular (LV) chamber. The restitution slope was increased to a greater extent for the JTend vs. the JTpeak interval. In contrast, flecainide reduced the APD90 restitution slope at LV epicardium without producing effect at LV endocardium and RV epicardium, and reduced the JTpeak restitution slope without changing the JTend restitution. Nevertheless, with all agents, these effects translated to the amplified epicardial-to-endocardial and the LV-to-RV non-uniformities in APD90 restitution, paralleled by the increased JTend vs. JTpeak difference in the restitution slope. In summary, these findings suggest that arrhythmic drug profiles are partly attributable to the accentuated regional heterogeneities in APD90 restitution, which can be indirectly determined through ECG assessments of the JTend vs. JTpeak dynamics at variable pacing rates.

The mechanism of retrovirus suppression of human T cell proliferation in vitro.

PubMed

Copelan, E A; Rinehart, J J; Lewis, M; Mathes, L; Olsen, R; Sagone, A

1983-10-01

Immunosuppression is commonly associated with retrovirus-induced animal tumors. Studies in the murine and feline retrovirus systems suggest that the 15,000-dalton envelope protein (p15E) of the virion may contribute to immunosuppression by interfering with normal lymphocyte function. We examined the effect of inactivated feline leukemia virus (UV-FeLV) and p15E derived from this virus on concanavalin A (Con A) driven human T cell proliferation. Virus and p15E markedly suppressed mononuclear cell proliferative response to Con A. Suppression was not due to inhibition of monocyte accessory cell function, or interleukin 1 (IL 1) secretion. In fact, the presence of monocytes partially protected T cells from UV-FeLV suppression. UV-FeLV, however, suppressed T cell secretion of and response to interleukin 2 (IL 2). We conclude that UV-FeLV and derived p15E inhibit T cell proliferation by direct inhibition of T cell function. These findings, extended to the in vivo situations, suggest that retrovirus-associated suppression of the immune response involves the induction of T cell but not monocyte dysfunction.

Specific Molecular Signatures for Type II Crustins in Penaeid Shrimp Uncovered by the Identification of Crustin-Like Antimicrobial Peptides in Litopenaeus vannamei

PubMed Central

Barreto, Cairé; Coelho, Jaqueline da Rosa; Yuan, Jianbo; Xiang, Jianhai; Perazzolo, Luciane Maria

2018-01-01

Crustins form a large family of antimicrobial peptides (AMPs) in crustaceans composed of four sub-groups (Types I-IV). Type II crustins (Type IIa or “Crustins” and Type IIb or “Crustin-like”) possess a typical hydrophobic N-terminal region and are by far the most representative sub-group found in penaeid shrimp. To gain insight into the molecular diversity of Type II crustins in penaeids, we identified and characterized a Type IIb crustin in Litopenaeus vannamei (Crustin-like Lv) and compared Type II crustins at both molecular and transcriptional levels. Although L. vannamei Type II crustins (Crustin Lv and Crustin-like Lv) are encoded by separate genes, they showed a similar tissue distribution (hemocytes and gills) and transcriptional response to the shrimp pathogens Vibrio harveyi and White spot syndrome virus (WSSV). As Crustin Lv, Crustin-like Lv transcripts were found to be present early in development, suggesting a maternal contribution to shrimp progeny. Altogether, our in silico and transcriptional data allowed to conclude that (1) each sub-type displays a specific amino acid signature at the C-terminal end holding both the cysteine-rich region and the whey acidic protein (WAP) domain, and that (2) shrimp Type II crustins evolved from a common ancestral gene that conserved a similar pattern of transcriptional regulation. PMID:29337853

Patient-specific coronary territory maps

NASA Astrophysics Data System (ADS)

Beliveau, Pascale; Setser, Randolph; Cheriet, Farida; O'Donnell, Thomas

2007-03-01

It is standard practice for physicians to rely on empirical, population based models to define the relationship between regions of left ventricular (LV) myocardium and the coronary arteries which supply them with blood. Physicians use these models to infer the presence and location of disease within the coronary arteries based on the condition of the myocardium within their distribution (which can be established non-invasively using imaging techniques such as ultrasound or magnetic resonance imaging). However, coronary artery anatomy often varies from the assumed model distribution in the individual patient; thus, a non-invasive method to determine the correspondence between coronary artery anatomy and LV myocardium would have immediate clinical impact. This paper introduces an image-based rendering technique for visualizing maps of coronary distribution in a patient-specific approach. From an image volume derived from computed tomography (CT) images, a segmentation of the LV epicardial surface, as well as the paths of the coronary arteries, is obtained. These paths form seed points for a competitive region growing algorithm applied to the surface of the LV. A ray casting procedure in spherical coordinates from the center of the LV is then performed. The cast rays are mapped to a two-dimensional circular based surface forming our coronary distribution map. We applied our technique to a patient with known coronary artery disease and a qualitative evaluation by an expert in coronary cardiac anatomy showed promising results.

Doppler-derived myocardial performance index in patients with impaired left ventricular relaxation and preserved systolic function.

PubMed

Fernandes, José Maria G; Rivera, Ivan Romero; de Oliveira Romão, Benício; Mendonça, Maria Alayde; Vasconcelos, Miriam Lira Castro; Carvalho, Antônio Carlos; Campos, Orlando; De Paola, Angelo Amato V; Moisés, Valdir A

2009-09-01

The Doppler-derived myocardial performance index (MPI) has been used in the evaluation of left ventricular (LV) function in several diseases. In patients with isolated diastolic dysfunction, the diagnostic utility of this index remains unclear. The aim of this study was to determine the diagnostic utility of MPI in patients with systemic hypertension, impaired LV relaxation, and normal ejection fraction. Thirty hypertensive patients with impaired LV relaxation were compared to 30 control subjects. MPI and its components, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), and the ejection time (ET), were measured from LV outflow and mitral inflow Doppler velocity profiles. MPI was higher in patients than in control subjects (0.45 +/- 0.13 vs 0.37 +/- 0.07 P < 0.0029). The increase in MPI was due to the prolongation of IRT without significant change of ICT and ET. MPI cutoff value of > or =0.40 identified impaired LV relaxation with a sensitivity of 63% and specificity of 70% while an IRT >94 ms had a sensitivity of 67% and specificity of 80%. Multivariate analysis identified relative wall thickness, mitral early filling wave velocity (E), and systolic myocardial velocity (Sm) as independent predictors of MPI in patients with hypertension. MPI was increase in patients with hypertension, diastolic dysfunction, and normal ejection fraction but was not superior to IRT to detect impaired LV relaxation.

Left atrial strain: a new parameter for assessment of left ventricular filling pressure.

PubMed

Cameli, Matteo; Mandoli, Giulia Elena; Loiacono, Ferdinando; Dini, Frank Lloyd; Henein, Michael; Mondillo, Sergio

2016-01-01

In order to obtain accurate diagnosis, treatment and prognostication in many cardiac conditions, there is a need for assessment of left ventricular (LV) filling pressure. While systole depends on ejection function of LV, diastole and its disturbances influence filling function and pressures. The commonest condition that represents the latter is heart failure with preserved ejection fraction in which LV ejection is maintained, but diastole is disturbed and hence filling pressures are raised. Significant diastolic dysfunction results in raised LV end-diastolic pressure, mean left atrial (LA) pressure and pulmonary capillary wedge pressure, all referred to as LV filling pressures. Left and right heart catheterization has traditionally been used as the gold standard investigation for assessing these pressures. More recently, Doppler echocardiography has taken over such application because of its noninvasive nature and for being patient friendly. A number of indices are used to achieve accurate assessment of filling pressures including: LV pulsed-wave filling velocities (E/A ratio, E wave deceleration time), pulmonary venous flow (S wave and D wave), tissue Doppler imaging (E' wave and E/E' ratio) and LA volume index. LA longitudinal strain derived from speckle tracking echocardiography (STE) is also sensitive in estimating intracavitary pressures. It is angle-independent, thus overcomes Doppler limitations and provides highly reproducible measures of LA deformation. This review examines the application of various Doppler echocardiographic techniques in assessing LV filling pressures, in particular the emerging role of STE in assessing LA pressures in various conditions, e.g., HF, arterial hypertension and atrial fibrillation.

Genomically Intact Endogenous Feline Leukemia Viruses of Recent Origin

PubMed Central

Roca, Alfred L.; Pecon-Slattery, Jill; O'Brien, Stephen J.

2004-01-01

We isolated and sequenced two complete endogenous feline leukemia viruses (enFeLVs), designated enFeLV-AGTT and enFeLV-GGAG. In enFeLV-AGTT, the open reading frames are reminiscent of a functioning FeLV genome, and the 5′ and 3′ long terminal repeat sequences are identical. Neither endogenous provirus is genetically fixed in cats but polymorphic, with 8.9 and 15.2% prevalence for enFeLV-AGTT and enFeLV-GGAG, respectively, among a survey of domestic cats. Neither provirus was found in the genomes of related species of the Felis genus, previously shown to harbor enFeLVs. The absence of mutational divergence, polymorphic incidence in cats, and absence in related species suggest that these enFeLVs may have entered the germ line more recently than previously believed, perhaps coincident with domestication, and reopens the question of whether some enFeLVs might be replication competent. PMID:15047851

Low-intensity interval exercise training attenuates coronary vascular dysfunction and preserves Ca²⁺-sensitive K⁺ current in miniature swine with LV hypertrophy.

PubMed

Emter, Craig A; Tharp, Darla L; Ivey, Jan R; Ganjam, Venkataseshu K; Bowles, Douglas K

2011-10-01

Coronary vascular dysfunction has been observed in several models of heart failure (HF). Recent evidence indicates that exercise training is beneficial for patients with HF, but the precise intensity and underlying mechanisms are unknown. Left ventricular (LV) hypertrophy can play a significant role in the development of HF; therefore, the purpose of this study was to assess the effects of low-intensity interval exercise training on coronary vascular function in sedentary (HF) and exercise trained (HF-TR) aortic-banded miniature swine displaying LV hypertrophy. Six months postsurgery, in vivo coronary vascular responses to endothelin-1 (ET-1) and adenosine were measured in the left anterior descending coronary artery. Baseline and maximal coronary vascular conductance were similar between all groups. ET-1-induced reductions in coronary vascular conductance (P < 0.05) were greater in HF vs. sedentary control and HF-TR groups. Pretreatment with the ET type A (ET(A)) receptor blocker BQ-123 prevented ET-1 hypersensitivity in HF animals. Whole cell voltage clamp was used to characterize composite K(+) currents (I(K(+))) in coronary smooth muscle cells. Raising internal Ca(2+) from 200 to 500 nM increased Ca(2+)-sensitive K(+) current in HF-TR and control, but not HF animals. In conclusion, an ET(A)-receptor-mediated hypersensitivity to ET-1, elevated resting LV wall tension, and decreased coronary smooth muscle cell Ca(2+)-sensitive I(K(+)) was found in sedentary animals with LV hypertrophy. Low-intensity interval exercise training preserved normal coronary vascular function and smooth muscle cell Ca(2+)-sensitive I(K(+)), illustrating a potential mechanism underlying coronary vascular dysfunction in a large-animal model of LV hypertrophy. Our results demonstrate the potential clinical impact of exercise on coronary vascular function in HF patients displaying pathological LV hypertrophy.

Low-intensity interval exercise training attenuates coronary vascular dysfunction and preserves Ca2+-sensitive K+ current in miniature swine with LV hypertrophy

PubMed Central

Tharp, Darla L.; Ivey, Jan R.; Ganjam, Venkataseshu K.; Bowles, Douglas K.

2011-01-01

Coronary vascular dysfunction has been observed in several models of heart failure (HF). Recent evidence indicates that exercise training is beneficial for patients with HF, but the precise intensity and underlying mechanisms are unknown. Left ventricular (LV) hypertrophy can play a significant role in the development of HF; therefore, the purpose of this study was to assess the effects of low-intensity interval exercise training on coronary vascular function in sedentary (HF) and exercise trained (HF-TR) aortic-banded miniature swine displaying LV hypertrophy. Six months postsurgery, in vivo coronary vascular responses to endothelin-1 (ET-1) and adenosine were measured in the left anterior descending coronary artery. Baseline and maximal coronary vascular conductance were similar between all groups. ET-1-induced reductions in coronary vascular conductance (P < 0.05) were greater in HF vs. sedentary control and HF-TR groups. Pretreatment with the ET type A (ETA) receptor blocker BQ-123 prevented ET-1 hypersensitivity in HF animals. Whole cell voltage clamp was used to characterize composite K+ currents (IK+) in coronary smooth muscle cells. Raising internal Ca2+ from 200 to 500 nM increased Ca2+-sensitive K+ current in HF-TR and control, but not HF animals. In conclusion, an ETA-receptor-mediated hypersensitivity to ET-1, elevated resting LV wall tension, and decreased coronary smooth muscle cell Ca2+-sensitive IK+ was found in sedentary animals with LV hypertrophy. Low-intensity interval exercise training preserved normal coronary vascular function and smooth muscle cell Ca2+-sensitive IK+, illustrating a potential mechanism underlying coronary vascular dysfunction in a large-animal model of LV hypertrophy. Our results demonstrate the potential clinical impact of exercise on coronary vascular function in HF patients displaying pathological LV hypertrophy. PMID:21841018

SIRT1 Overexpression Maintains Cell Phenotype and Function of Endothelial Cells Derived from Induced Pluripotent Stem Cells.

PubMed

Jiang, Bin; Jen, Michele; Perrin, Louisiane; Wertheim, Jason A; Ameer, Guillermo A

2015-12-01

Endothelial cells (ECs) that are differentiated from induced pluripotent stem cells (iPSCs) can be used in establishing disease models for personalized drug discovery or developing patient-specific vascularized tissues or organoids. However, a number of technical challenges are often associated with iPSC-ECs in culture, including instability of the endothelial phenotype and limited cell proliferative capacity over time. Early senescence is believed to be the primary mechanism underlying these limitations. Sirtuin1 (SIRT1) is an NAD(+)-dependent deacetylase involved in the regulation of cell senescence, redox state, and inflammatory status. We hypothesize that overexpression of the SIRT1 gene in iPSC-ECs will maintain EC phenotype, function, and proliferative capacity by overcoming early cell senescence. SIRT1 gene was packaged into a lentiviral vector (LV-SIRT1) and transduced into iPSC-ECs at passage 4. Beginning with passage 5, iPSC-ECs exhibited a fibroblast-like morphology, whereas iPSC-ECs overexpressing SIRT1 maintained EC cobblestone morphology. SIRT1 overexpressing iPSC-ECs also exhibited a higher percentage of canonical markers of endothelia (LV-SIRT1 61.8% CD31(+) vs. LV-empty 31.7% CD31(+), P < 0.001; LV-SIRT1 46.3% CD144(+) vs. LV-empty 20.5% CD144(+), P < 0.02), with a higher nitric oxide synthesis, lower β-galactosidase production indicating decreased senescence (3.4% for LV-SIRT1 vs. 38.6% for LV-empty, P < 0.001), enhanced angiogenesis, increased deacetylation activity, and higher proliferation rate. SIRT1 overexpressing iPSC-ECs continued to proliferate through passage 9 with high purity of EC-like characteristics, while iPSC-ECs without SIRT1 overexpression became senescent after passage 5. Taken together, SIRT1 overexpression in iPSC-ECs maintains EC phenotype, improves EC function, and extends cell lifespan, overcoming critical hurdles associated with the use of iPSC-ECs in translational research.

Strain, strain rate, and the force frequency relationship in patients with and without heart failure.

PubMed

Mak, Susanna; Van Spall, Harriette G C; Wainstein, Rodrigo V; Sasson, Zion

2012-03-01

The aim of this study was to examine the effect of heart rate (HR) on indices of deformation in adults with and without heart failure (HF) who underwent simultaneous high-fidelity catheterization of the left ventricle to describe the force-frequency relationship. Right atrial pacing to control HR and high-fidelity recordings of left ventricular (LV) pressure were used to inscribe the force-frequency relationship. Simultaneous two-dimensional echocardiographic imaging was acquired for speckle-tracking analysis. Thirteen patients with normal LV function and 12 with systolic HF (LV ejection fraction, 31 ± 13%) were studied. Patients with HF had depressed isovolumic contractility and impaired longitudinal strain and strain rate. HR-dependent increases in LV+dP/dt(max), the force-frequency relationship, was demonstrated in both groups (normal LV function, baseline to 100 beats/min: 1,335 ± 296 to 1,564 ± 320 mm Hg/sec, P < .0001; HF, baseline to 100 beats/min: 970 ± 207 to 1,083 ± 233 mm Hg/sec, P < .01). Longitudinal strain decreased significantly (normal LV function, baseline to 100 beats/min: 18.0 ± 3.5% to 10.8 ± 6.0%, P < .001; HF: 9.4 ± 4.1% to 7.5 ± 3.4%, P < .01). The decrease in longitudinal strain was related to a decrease in LV end-diastolic dimensions. Strain rate did not change with right atrial pacing. Despite the inotropic effect of increasing HR, longitudinal strain decreases in parallel with stroke volume as load-dependent indices of ejection. Strain rate did not reflect the modest HR-related changes in contractility; on the other hand, the use of strain rate for quantitative stress imaging is also less likely to be confounded by chronotropic responses. Copyright © 2012 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

A targeted mutation within the feline leukemia virus (FeLV) envelope protein immunosuppressive domain to improve a canarypox virus-vectored FeLV vaccine.

PubMed

Schlecht-Louf, Géraldine; Mangeney, Marianne; El-Garch, Hanane; Lacombe, Valérie; Poulet, Hervé; Heidmann, Thierry

2014-01-01

We previously delineated a highly conserved immunosuppressive (IS) domain within murine and primate retroviral envelope proteins that is critical for virus propagation in vivo. The envelope-mediated immunosuppression was assessed by the ability of the proteins, when expressed by allogeneic tumor cells normally rejected by engrafted mice, to allow these cells to escape, at least transiently, immune rejection. Using this approach, we identified key residues whose mutation (i) specifically abolishes immunosuppressive activity without affecting the "mechanical" function of the envelope protein and (ii) significantly enhances humoral and cellular immune responses elicited against the virus. The objective of this work was to study the immunosuppressive activity of the envelope protein (p15E) of feline leukemia virus (FeLV) and evaluate the effect of its abolition on the efficacy of a vaccine against FeLV. Here we demonstrate that the FeLV envelope protein is immunosuppressive in vivo and that this immunosuppressive activity can be "switched off" by targeted mutation of a specific amino acid. As a result of the introduction of the mutated envelope sequence into a previously well characterized canarypox virus-vectored vaccine (ALVAC-FeLV), the frequency of vaccine-induced FeLV-specific gamma interferon (IFN-γ)-producing cells was increased, whereas conversely, the frequency of vaccine-induced FeLV-specific interleukin-10 (IL-10)-producing cells was reduced. This shift in the IFN-γ/IL-10 response was associated with a higher efficacy of ALVAC-FeLV against FeLV infection. This study demonstrates that FeLV p15E is immunosuppressive in vivo, that the immunosuppressive domain of p15E can modulate the FeLV-specific immune response, and that the efficacy of FeLV vaccines can be enhanced by inhibiting the immunosuppressive activity of the IS domain through an appropriate mutation.

Fitness in Young Adulthood and Long-Term Cardiac Structure and Function: The CARDIA Study.

PubMed

Pandey, Ambarish; Allen, Norrina B; Ayers, Colby; Reis, Jared P; Moreira, Henrique T; Sidney, Stephen; Rana, Jamal S; Jacobs, David R; Chow, Lisa S; de Lemos, James A; Carnethon, Mercedes; Berry, Jarett D

2017-05-01

This study sought to evaluate the association between early-life cardiorespiratory fitness (CRF) and measures of left ventricular (LV) structure and function in midlife. Low CRF in midlife is associated with a higher risk of heart failure. However, the unique contributions of early-life CRF toward measures of LV structure and function in middle age are not known. CARDIA (Coronary Artery Risk Development in Young Adults) study participants with a baseline maximal treadmill test and an echocardiogram at year 25 were included. Associations among baseline CRF, CRF change, and echocardiographic LV parameters (global longitudinal strain [GLS] and global circumferential strain, E/e') were assessed using multivariable linear regression. The study included 3,433 participants. After adjustment for baseline demographic and clinical characteristics, lower baseline CRF was significantly associated with higher LV strain (standardized parameter estimate [Std β] = -0.06; p = 0.03 for GLS) and ratio of early transmitral flow velocity to early peak diastolic mitral annular velocity (E/e') (Std β = -0.10; p = 0.0001 for lateral E/e'), findings suggesting impaired contractility and elevated diastolic filling pressure in midlife. After additional adjustment for cumulative cardiovascular risk factor burden observed over the follow-up period, the association of CRF with LV strain attenuated substantially (p = 0.36), whereas the association with diastolic filling pressure remained significant (Std β = -0.05; p = 0.02 for lateral E/e'). In a subgroup of participants with repeat CRF tests at year 20, greater decline in CRF was significantly associated with increased abnormalities in GLS (Std β = -0.05; p = 0.02) and higher diastolic filling pressure (Std β = -0.06; p = 0.006 for lateral E/e') in middle age. CRF in young adulthood and CRF change were associated with measures of LV systolic function and diastolic filling pressure in middle age. Low CRF-associated abnormalities in systolic function were related to the associated higher cardiovascular risk factor burden. In contrast, the inverse association between CRF and LV diastolic filling pressure was independent of cardiovascular risk factor burden. Copyright © 2017. Published by Elsevier Inc.

Intrafamilial aggregation and heritability of tissue Doppler indexes of left ventricular diastolic function in a group of African descent.

PubMed

Peterson, Vernice R; Norton, Gavin R; Libhaber, Carlos D; Maseko, Muzi J; Sareli, Pinhas; Woodiwiss, Angela J

2016-06-01

Although several indexes of left ventricular (LV) diastolic function show heritability, the genetic influence on the tissue Doppler index, E/e' (early transmitral velocity/velocity of myocardial tissue lengthening), an index of LV filling pressures in those of black African descent is currently unknown. Furthermore, whether any genetic influences on E/e' are through an impact of LV remodeling or aortic function is unknown. Intrafamilial aggregation and heritability (SAGE software) of E/e' (echocardiography) were assessed in 129 nuclear families (29 spouse pairs, 216 parent-child pairs, and 113 sibling-sibling pairs) from an urban developing community of black Africans, independent of LV mass index (LVMI), LV relative wall thickness (RWT), central aortic systolic pressure (SBPc), and backward wave pressures (Pb) (applanation tonometry, SphygmoCor software). Independent of confounders including LVMI and RWT, E/e' was correlated in parent-child (r = 0.23; P < .001) and sibling-sibling (r = 0.29; P < .005), but not in spouse (r = 0.13; P = .51) pairs. The relationships between parent-child (r = 0.22; P < .001) and sibling-sibling (r = 0.29; P < .005) pairs persisted with adjustments for SBPc. The relationships between parent-child (r = 0.22; P < .001) and sibling-sibling (r = 0.26; P < .01) pairs also persisted with adjustments for Pb. Independent of confounders including LVMI and RWT, E/e' showed significant heritability (h(2) ± standard error of the mean [SEM] = 0.51 ± 0.11; P < .0001) which similarly persisted with adjustments for SBPc (h(2) ± SEM = 0.50 ± 0.11; P < .0001) and Pb (h(2) ± SEM = 0.49 ± 0.11; P < .0001). In conclusion, in a group of African ancestry, independent of LV remodeling and aortic function, E/e' shows significant intrafamilial aggregation and robust heritability. Hence, genetic factors may play an important role in determining moderate-to-severe LV diastolic dysfunction independent of cardiac remodeling or aortic function in groups of black African ancestry. Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Characterization of Regional Left Ventricular Function in Nonhuman Primates Using Magnetic Resonance Imaging Biomarkers: A Test-Retest Repeatability and Inter-Subject Variability Study

PubMed Central

Sampath, Smita; Klimas, Michael; Feng, Dai; Baumgartner, Richard; Manigbas, Elaine; Liang, Ai-Leng; Evelhoch, Jeffrey L.; Chin, Chih-Liang

2015-01-01

Pre-clinical animal models are important to study the fundamental biological and functional mechanisms involved in the longitudinal evolution of heart failure (HF). Particularly, large animal models, like nonhuman primates (NHPs), that possess greater physiological, biochemical, and phylogenetic similarity to humans are gaining interest. To assess the translatability of these models into human diseases, imaging biomarkers play a significant role in non-invasive phenotyping, prediction of downstream remodeling, and evaluation of novel experimental therapeutics. This paper sheds insight into NHP cardiac function through the quantification of magnetic resonance (MR) imaging biomarkers that comprehensively characterize the spatiotemporal dynamics of left ventricular (LV) systolic pumping and LV diastolic relaxation. MR tagging and phase contrast (PC) imaging were used to quantify NHP cardiac strain and flow. Temporal inter-relationships between rotational mechanics, myocardial strain and LV chamber flow are presented, and functional biomarkers are evaluated through test-retest repeatability and inter subject variability analyses. The temporal trends observed in strain and flow was similar to published data in humans. Our results indicate a dominant dimension based pumping during early systole, followed by a torsion dominant pumping action during late systole. Early diastole is characterized by close to 65% of untwist, the remainder of which likely contributes to efficient filling during atrial kick. Our data reveal that moderate to good intra-subject repeatability was observed for peak strain, strain-rates, E/circumferential strain-rate (CSR) ratio, E/longitudinal strain-rate (LSR) ratio, and deceleration time. The inter-subject variability was high for strain dyssynchrony, diastolic strain-rates, peak torsion and peak untwist rate. We have successfully characterized cardiac function in NHPs using MR imaging. Peak strain, average systolic strain-rate, diastolic E/CSR and E/LSR ratios, and deceleration time were identified as robust biomarkers that could potentially be applied to future pre-clinical drug studies. PMID:26010607

Disruption of Thiamine Uptake and Growth of Cells by Feline Leukemia Virus Subgroup A

PubMed Central

Mendoza, Ramon; Miller, A. Dusty

2013-01-01

Feline leukemia virus (FeLV) is still a major cause of morbidity and mortality in domestic cats and some wild cats despite the availability of relatively effective vaccines against the virus. FeLV subgroup A (FeLV-A) is transmitted in natural infections, and FeLV subgroups B, C, and T can evolve directly from FeLV-A by mutation and/or recombination with endogenous retroviruses in domestic cats, resulting in a variety of pathogenic outcomes. The cell surface entry receptor for FeLV-A is a putative thiamine transporter (THTR1). Here, we have addressed whether FeLV-A infection might disrupt thiamine uptake into cells and, because thiamine is an essential nutrient, whether this disruption might have pathological consequences. First, we cloned the cat ortholog of the other of the two known thiamine transporters in mammals, THTR2, and we show that feline THTR1 (feTHTR1) and feTHTR2 both mediate thiamine uptake, but feTHTR2 does not function as a receptor for FeLV-A. We found that feTHTR1 is widely expressed in cat tissues and in cell lines, while expression of feTHTR2 is restricted. Thiamine uptake mediated by feTHTR1 was indeed blocked by FeLV-A infection, and in feline fibroblasts that naturally express feTHTR1 and not feTHTR2, this blockade resulted in a growth arrest at physiological concentrations of extracellular thiamine. The growth arrest was reversed at high extracellular concentrations of thiamine. Our results show that FeLV-A infection can indeed disrupt thiamine uptake with pathological consequences. A prediction of these experiments is that raising the plasma levels of thiamine in FeLV-infected cats may ameliorate the pathogenic effects of infection. PMID:23269813

Disruption of thiamine uptake and growth of cells by feline leukemia virus subgroup A.

PubMed

Mendoza, Ramon; Miller, A Dusty; Overbaugh, Julie

2013-03-01

Feline leukemia virus (FeLV) is still a major cause of morbidity and mortality in domestic cats and some wild cats despite the availability of relatively effective vaccines against the virus. FeLV subgroup A (FeLV-A) is transmitted in natural infections, and FeLV subgroups B, C, and T can evolve directly from FeLV-A by mutation and/or recombination with endogenous retroviruses in domestic cats, resulting in a variety of pathogenic outcomes. The cell surface entry receptor for FeLV-A is a putative thiamine transporter (THTR1). Here, we have addressed whether FeLV-A infection might disrupt thiamine uptake into cells and, because thiamine is an essential nutrient, whether this disruption might have pathological consequences. First, we cloned the cat ortholog of the other of the two known thiamine transporters in mammals, THTR2, and we show that feline THTR1 (feTHTR1) and feTHTR2 both mediate thiamine uptake, but feTHTR2 does not function as a receptor for FeLV-A. We found that feTHTR1 is widely expressed in cat tissues and in cell lines, while expression of feTHTR2 is restricted. Thiamine uptake mediated by feTHTR1 was indeed blocked by FeLV-A infection, and in feline fibroblasts that naturally express feTHTR1 and not feTHTR2, this blockade resulted in a growth arrest at physiological concentrations of extracellular thiamine. The growth arrest was reversed at high extracellular concentrations of thiamine. Our results show that FeLV-A infection can indeed disrupt thiamine uptake with pathological consequences. A prediction of these experiments is that raising the plasma levels of thiamine in FeLV-infected cats may ameliorate the pathogenic effects of infection.

Integrated multimodal-catheter imaging unveils principal relationships among ventricular electrical activity, anatomy, and function.

PubMed

Rao, Liyun; Ling, Yuesheng; He, Renjie; Gilbert, April L; Frangogiannis, Nikolaos G; Wang, Jianwen; Nagueh, Sherif F; Khoury, Dirar S

2008-02-01

Multiple imaging modalities are employed independent of one another while managing complex cardiac arrhythmias. To combine electrical, anatomical, and functional imaging in a single catheter system, we developed a balloon catheter that carried 64 electrodes on its surface and an intracardiac echocardiography (ICE) catheter through a central lumen. The catheter system was inserted, and the balloon was inflated inside the left ventricle (LV) of eight dogs with 6-wk-old infarction, created by occlusion in the left anterior descending coronary artery. Anatomy was constructed by ICE imaging (9 MHz) through the balloon. Single-beat noncontact mapping (NCM) was performed via the multielectrode array to reconstruct unipolar endocardial electrograms during sinus rhythm. Standard contact mapping (CM) of the endocardium was also carried out for reference. Myocardial infarction in anterior LV extending from the middle to apical regions was localized both by ICE and NCM and validated by CM and pathology. The overall difference in the activation times between NCM and CM was 3 +/- 1 ms. Unipolar voltage in infarcted middle anterior LV was smaller than the voltage in normal middle inferior LV both by NCM (11 +/- 4 vs. 16 +/- 3 mV; P = 0.002) and CM (11 +/- 3 vs. 20 +/- 4 mV; P < 0.001). Unipolar voltage was also inversely related to infarct transmurality, both by NCM (r = -0.87; P = 0.005) and CM (r = -0.94; P < 0.001). The infarct area by ICE (7.7 +/- 2.9 cm(2)) was in agreement with CM (bipolar voltage, <1 mV; and area, 7.6 +/- 3.3 cm(2); r = 0.80; P = 0.016). Meanwhile, the voltage threshold that depicted the infarct area by NCM was directly related to the smallest unipolar voltage reconstructed within the infarct (r = 0.96; P < 0.001). In conclusion, combining NCM and ICE imaging in a single catheter system is feasible. The preclinical development of such an integrated system and its evaluation in experimental myocardial infarction demonstrate capabilities for single-beat mapping at multiple sites as well as the online assessment of anatomy and myocardial function.

Effect of balloon mitral valvotomy on left ventricular function in rheumatic mitral stenosis.

PubMed

Rajesh, Gopalan Nair; Sreekumar, Pradeep; Haridasan, Vellani; Sajeev, C G; Bastian, Cicy; Vinayakumar, D; Kadermuneer, P; Mathew, Dolly; George, Biju; Krishnan, M N

Mitral stenosis (MS) is found to produce left ventricular (LV) dysfunction in some studies. We sought to study the left ventricular function in patients with rheumatic MS undergoing balloon mitral valvotomy (BMV). Ours is the first study to analyze effect of BMV on mitral annular plane systolic excursion (MAPSE), and to quantify prevalence of longitudinal left ventricular dysfunction in rheumatic MS. In this prospective cohort study, we included 43 patients with severe rheumatic mitral stenosis undergoing BMV. They were compared to twenty controls whose distribution of age and gender were similar to that of patients. The parameters compared were LV ejection fraction (EF) by modified Simpson's method, mitral annular systolic velocity (MASV), MAPSE, mitral annular early diastolic velocity (E'), and myocardial performance index (MPI). These parameters were reassessed immediately following BMV and after 3 months of procedure. MASV, MAPSE, E', and EF were significantly lower and MPI was higher in mitral stenosis group compared to controls. Impaired longitudinal LV function was present in 77% of study group. MAPSE and EF did not show significant change after BMV while MPI, MASV, and E' improved significantly. MASV and E' showed improvement immediately after BMV, while MPI decreased only at 3 months follow-up. There were significantly lower mitral annular motion parameters including MAPSE in patients with rheumatic mitral stenosis. Those with atrial fibrillation had higher MPI. Immediately after BMV, there was improvement in LV long axis function with a gradual improvement in global LV function. There was no significant change of MAPSE after BMV. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Enhanced mesenchymal cell engraftment by IGF-1 improves left ventricular function in rats undergoing myocardial infarction.

PubMed

Enoki, Chiharu; Otani, Hajime; Sato, Daisuke; Okada, Takayuki; Hattori, Reiji; Imamura, Hiroji

2010-01-07

We hypothesized that enhanced mesenchymal cell (MC) engraftment with insulin-like growth factor-1 (IGF-1) improves left ventricular (LV) function and survival. IGF-1 (10 microg/ml) increased adhesion and inhibited apoptosis under hypoxia in vitro through activation of phosphatidylinositol 3-kinase (PI3K) in bone marrow-derived MCs obtained from transgenic rats expressing green fluorescence protein. Myocardial infarction (MI) in rats was produced by ligature of the left coronary artery. One month after MI, rat hearts were injected with MCs in the presence or absence of 10 microg/ml IGF-1 with or without PI3K inhibitor, 5 microM LY294002. IGF-1 significantly increased engraftment of MCs between 6 h and 3 days after transplantation associated with the increase in stromal cell-derived factor-1alpha in the infracted LV. The transplanted MCs had disappeared 1 month after transplantation in all groups. MC transplantation with IGF-1 significantly increased neovascularization and inhibited cardiomyocyte apoptosis 3 days and 1 month after MC transplantation. This was associated with improved LV function 1 month after MC transplantation and eventually survival. LY294002 abrogated all of the beneficial effects of MC transplantation with IGF-1. IGF-1 alone had no effect on neovascularization and did not improve LV function and/or survival. These results suggest that IGF-1 improves engraftment of MCs at the time of transplantation via activation of PI3K and this improved engraftment of MCs may be attributed to an increased neovascularization and inhibition of cardiomyocyte death, leading to improvement of LV function and prolongation of survival despite the eventual loss of the transplanted MCs.

Sleep Duration and Quality as Related to Left Ventricular Structure and Function.

PubMed

Lee, Jae-Hon; Park, Sung Keun; Ryoo, Jae-Hong; Oh, Chang-Mo; Kang, Jeong Gyu; Mansur, Rodrigo B; Alfonsi, Jeffrey E; Lee, Yena; Shin, Sun-Han; McIntyre, Roger S; Jung, Ju Young

2018-01-01

Inadequate sleep is associated with increased risk of cardiovascular events; however, the associations between sleep duration or quality and cardiac function or structure are not well understood. This cross-sectional study was conducted to investigate to what extent sleep duration and quality are associated with left ventricular (LV) diastolic dysfunction or structural deterioration. A total of 31,598 healthy Korean adults who received echocardiography and completed the Pittsburg Sleep Quality Index were enrolled in this study. Participants were stratified into three groups by self-reported sleep duration (i.e., <7, 7-9, >9 hours) and into two groups by subjective sleep quality. Sleep duration was also assessed as a continuous variable. The odds ratios for impaired LV diastolic function, increased relative wall thickness, and LV hypertrophy (LVH) were compared between groups using multivariable logistic regression analyses. After adjustment for confounding variables (e.g., age, smoking, body mass index), there was a statistically significant association between short sleep duration (<7 hours) and greater LVH (fully adjusted odds ratio = 1.32 [95% confidence interval {CI} = 1.02-1.73]). Short sleep duration was also significantly associated with greater LVH (0.87 per hour [95% CI = 0.78-0.98]) and increased relative wall thickness (0.92 [95% CI = 0.86-0.99]), but there was no significant association between sleep and LV diastolic function. Among individuals with normal sleep duration, poor quality of sleep was not associated with adverse cardiac measures. These results indicate that short sleep duration (<7 hours) is associated with unfavorable LV structural characteristics. The association of insufficient sleep with adverse cardiovascular health outcomes may be mediated in part by adverse changes in cardiac structure and function.

An evaluation of the use of new Doppler methods for detecting longitudinal function abnormalities in a pacing-induced heart failure model

NASA Technical Reports Server (NTRS)

Tabata, Tomotsugu; Cardon, Lisa A.; Armstrong, Guy P.; Fukamach, Kiyotaka; Takagaki, Masami; Ochiai, Yoshie; McCarthy, Patrick M.; Thomas, James D.

2003-01-01

BACKGROUND: Doppler tissue echocardiography and color M-mode Doppler flow propagation velocity have proven useful in evaluating cross-sections of patients with left ventricular (LV) dysfunction, but experience with serial changes is limited. Purpose and methods: We tested their use by evaluating the temporal changes of LV function in a pacing-induced congestive heart failure model. Rapid ventricular pacing was initiated and maintained in 20 dogs for 4 weeks. Echocardiography was performed at baseline and weekly during brief pacing cessation. RESULTS: With rapid pacing, LV volume significantly increased and ejection fraction (57%-28%), stroke volume (37-18 mL), and mitral annulus systolic velocity (16.1-6.6 cm/s) by Doppler tissue echocardiography significantly decreased, with ejection fraction and mitral annulus systolic velocity closely correlated (r = 0.706, P <.0001). In contrast to the mitral inflow velocities, mitral annulus early diastolic velocity decreased steadily (12.3-7.3 cm/s) resulting in a dramatic decrease in mitral annulus early/late (1.22-0.57) diastolic velocity with no tendency toward pseudonormalization. The color M-mode Doppler flow propagation velocity also showed significant steady decrease (57-24 cm/s) throughout the pacing period. Multiple regression analysis chose mitral annulus systolic velocity (r = 0.895, P <.0001) and propagation velocity (r = 0.782, P <.0001) for the most important factor predicting LV systolic and diastolic function, respectively. CONCLUSIONS: Doppler tissue echocardiography and color M-mode Doppler flow could evaluate the serial deterioration in LV dysfunction throughout the pacing period. These were more useful in quantifying progressive LV dysfunction than conventional ehocardiographic techniques, and were probably relatively independent of preload. These techniques could be suitable for longitudinal evaluation in addition to the cross-sectional study.

Operator induced variability in left ventricular measurements with cardiovascular magnetic resonance is improved after training.

PubMed

Karamitsos, Theodoros D; Hudsmith, Lucy E; Selvanayagam, Joseph B; Neubauer, Stefan; Francis, Jane M

2007-01-01

Accurate and reproducible measurement of left ventricular (LV) mass and function is a significant strength of Cardiovascular Magnetic Resonance (CMR). Reproducibility and accuracy of these measurements is usually reported between experienced operators. However, an increasing number of inexperienced operators are now training in CMR and are involved in post-processing analysis. The aim of the study was to assess the interobserver variability of the manual planimetry of LV contours amongst two experienced and six inexperienced operators before and after a two months training period. Ten healthy normal volunteers (5 men, mean age 34+/-14 years) comprised the study population. LV volumes, mass, and ejection fraction were manually evaluated using Argus software (Siemens Medical Solutions, Erlangen, Germany) for each subject, once by the two experienced and twice by the six inexperienced operators. The mean values of experienced operators were considered the reference values. The agreement between operators was evaluated by means of Bland-Altman analysis. Training involved standardized data acquisition, simulated off-line analysis and mentoring. The trainee operators demonstrated improvement in the measurement of all the parameters compared to the experienced operators. The mean ejection fraction variability improved from 7.2% before training to 3.7% after training (p=0.03). The parameter in which the trainees showed the least improvement was LV mass (from 7.7% to 6.7% after training). The basal slice selection and contour definition were the main sources of errors. An intensive two month training period significantly improved the accuracy of LV functional measurements. Adequate training of new CMR operators is of paramount importance in our aim to maintain the accuracy and high reproducibility of CMR in LV function analysis.

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics.

PubMed

Schneider, Caroline; Forsythe, Lynsey; Somauroo, John; George, Keith; Oxborough, David

2018-01-03

Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function however the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change. A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years,) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume-loops (deformation-volume analysis - DVA). There was a leftward- shift of the ε -volume loop from supine to 1 min and 5 min of HUT, p<0.001). Moreover, longitudinal shortening was reduced (p<0.001) with a concomitant increase in transverse thickening from supine to 1min, which was further augmented at 5min (p=0.018). Preload reduction occurs within 1 minute of HUT but does not further reduce at 5 minutes. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations. © 2018 The authors.

Ideal cardiovascular health in childhood-Longitudinal associations with cardiac structure and function: The Special Turku Coronary Risk Factor Intervention Project (STRIP) and the Cardiovascular Risk in Young Finns Study (YFS).

PubMed

Laitinen, Tomi T; Ruohonen, Saku; Juonala, Markus; Magnussen, Costan G; Mikkilä, Vera; Mikola, Hanna; Hutri-Kähönen, Nina; Laitinen, Tomi; Tossavainen, Päivi; Jokinen, Eero; Niinikoski, Harri; Jula, Antti; Viikari, Jorma S A; Rönnemaa, Tapani; Raitakari, Olli T; Pahkala, Katja

2017-03-01

Ideal cardiovascular health (CVH), defined by the American Heart Association, is associated with incident cardiovascular disease in adults. However, association of the ideal CVH in childhood with current and future cardiac structure and function has not been studied. The sample comprised 827 children participating in the longitudinal Special Turku Coronary Risk Factor Intervention Project (STRIP) and The Cardiovascular Risk in Young Finns Study (YFS). In STRIP, complete data on the seven ideal CVH metrics and left ventricular (LV) mass measured with echocardiography were available at the age of 15 (n=321), 17 (n=309) and 19 (n=283) years. In YFS, the cohort comprised children aged 12-18years (n=506) with complete ideal CVH metrics data from childhood and 25years later in adulthood, and echocardiography performed in adulthood. In STRIP, ideal CVH score was inversely associated with LV mass during childhood (P=0.036). In YFS, childhood ideal CVH score was inversely associated with LV mass, LV end-diastolic volume, E/e' ratio, and left atrium end-systolic volume in adulthood (all P<0.01). In addition, improvement of the ideal CVH score between childhood and adulthood was inversely associated with LV mass, LV end-diastolic volume, E/e' ratio, and left atrium end-systolic volume (all P≤0.03). Childhood ideal CVH score has a long-lasting effect on cardiac structure and function, and the association is evident already in childhood. Our findings support targeting the ideal CVH metrics as part of primordial prevention of cardiovascular diseases. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Inter-study reproducibility of cardiovascular magnetic resonance tagging

PubMed Central

2013-01-01

Background The aim of this study is to determine the test-retest reliability of the measurement of regional myocardial function by cardiovascular magnetic resonance (CMR) tagging using spatial modulation of magnetization. Methods Twenty-five participants underwent CMR tagging twice over 12 ± 7 days. To assess the role of slice orientation on strain measurement, two healthy volunteers had a first exam, followed by image acquisition repeated with slices rotated ±15 degrees out of true short axis, followed by a second exam in the true short axis plane. To assess the role of slice location, two healthy volunteers had whole heart tagging. The harmonic phase (HARP) method was used to analyze the tagged images. Peak midwall circumferential strain (Ecc), radial strain (Err), Lambda 1, Lambda 2, and Angle α were determined in basal, mid and apical slices. LV torsion, systolic and early diastolic circumferential strain and torsion rates were also determined. Results LV Ecc and torsion had excellent intra-, interobserver, and inter-study intra-class correlation coefficients (ICC range, 0.7 to 0.9). Err, Lambda 1, Lambda 2 and angle had excellent intra- and interobserver ICC than inter-study ICC. Angle had least inter-study reproducibility. Torsion rates had superior intra-, interobserver, and inter-study reproducibility to strain rates. The measurements of LV Ecc were comparable in all three slices with different short axis orientations (standard deviation of mean Ecc was 0.09, 0.18 and 0.16 at basal, mid and apical slices, respectively). The mean difference in LV Ecc between slices was more pronounced in most of the basal slices compared to the rest of the heart. Conclusions Intraobserver and interobserver reproducibility of all strain and torsion parameters was excellent. Inter-study reproducibility of CMR tagging by SPAMM varied between different parameters as described in the results above and was superior for Ecc and LV torsion. The variation in LV Ecc measurement due to altered slice orientation is negligible compared to the variation due to slice location. Trial registration This trial is registered as NCT00005487 at National Heart, Lung and Blood institute. PMID:23663535

Risk Stratification of Future Left Ventricular Dysfunction for Patients with Indications for Right Ventricular Pacing due to Bradycardia.

PubMed

Ooka, Junichi; Tanaka, Hidekazu; Hatani, Yutaka; Hatazawa, Keiko; Matsuzoe, Hiroki; Shimoura, Hiroyuki; Sano, Hiroyuki; Sawa, Takuma; Motoji, Yoshiki; Mochizuki, Yasuhide; Ryo-Koriyama, Keiko; Matsumoto, Kensuke; Fukuzawa, Koji; Hirata, Ken-Ichi

2017-10-21

Although right ventricular (RV) pacing is the only effective treatment for patients with symptomatic bradycardia, it creates left ventricular (LV) dyssynchrony, which can induce LV dysfunction and heart failure. The current criterion for consideration of cardiac resynchronization therapy (CRT) is LV ejection fraction (LVEF) ≤ 35%, but indication for CRT in patients required for RV pacing with LVEF > 35% remains unclear.We studied 40 patients, all LVEF ≥ 35%, who had undergone implantable cardioverter-defibrillator implantation with RV pacing < 5%. Echocardiography was performed at baseline and during RV pacing. LV dyssynchrony was defined as anteroseptal-to-posterior wall delay from the mid-LV short-axis view using two-dimensional speckle-tracking radial strain (significant: ≥ 130 ms). Patients were divided into two groups based on baseline LVEF: normal LVEF ( ≥ 50%; n = 20) and mildly reduced LVEF (35-50%; n = 20).LVEF and LV dyssynchrony in patients with mildly reduced LVEF deteriorated significantly during RV pacing compared to those in patients with normal LVEF. Moreover, changes in LV dyssynchrony during RV pacing significantly correlated with changes in LVEF (r = -0.44, P < 0.01). Multivariate logistic regression analysis showed that baseline LVEF was the only independent predictor and baseline LVEF < 48% predictive of significant LV dyssynchrony during RV pacing.The extent of RV pacing-induced LV dysfunction may be associated with baseline LV function. These adverse effects on patients with mildly reduced LVEF of 35-50% and indications for RV pacing due to bradycardia can thus be prevented by CRT.

Extracorporeal shockwave myocardial revascularization improves clinical symptoms and left ventricular function in patients with refractory angina.

PubMed

Zuozienė, Gitana; Laucevičius, Aleksandras; Leibowitz, David

2012-01-01

Medical therapy for refractory angina is limited and the prognosis is poor. Experimental data suggest that the use of extracorporeal shockwave myocardial revascularization (ESMR) can contribute to angiogenesis and improve symptoms of angina and left ventricular (LV) function. The objective of this study was to examine the effects of ESMR on clinical symptoms as well as LV function as assessed by cardiac MRI in patients with refractory angina. Patients with Canadian Cardiovascular Society (CCS) class III-IV angina despite medical therapy and ischemia documented on thallium or echo-dobutamine were eligible for the study. ESMR therapy was applied with a commercially available cardiac shockwave generator system under echocardiographic guidance. LV function was assessed before and 6 months after therapy by cardiac MRI. Twenty patients (four women, 16 men; mean age 64 years, range 45-83) were included in the study. The CCS class after treatment improved in all patients (16 patients angina pectoris CCS from III to II and four patients from IV to III). The use of sublingual nitroglycerin was significantly reduced as well. There was a significant improvement in LV ejection fraction as assessed by blinded MRI following therapy in the overall population (51 vs. 59%, P<0.05). This study demonstrates the potential efficacy of ESMR for the treatment of refractory angina pectoris. The patients showed both a significant clinical response as well as improved LV ejection fraction on serial MRI imaging. Larger studies are needed to adequately define the clinical utility of this novel therapy.

Obesity and heart failure.

PubMed

De Pergola, Giovanni; Nardecchia, Adele; Giagulli, Vito Angelo; Triggiani, Vincenzo; Guastamacchia, Edoardo; Minischetti, Manuela Castiglione; Silvestris, Franco

2013-03-01

Epidemiological studies have recently shown that obesity, and abdominal obesity in particular, is an independent risk factor for the development of heart failure (HF). Higher cardiac oxidative stress is the early stage of heart dysfunction due to obesity, and it is the result of insulin resistance, altered fatty acid and glucose metabolism, and impaired mitochondrial biogenesis. Extense myocyte hypertrophy and myocardial fibrosis are early microscopic changes in patients with HF, whereas circumferential strain during the left ventricular (LV) systole, LV increase in both chamber size and wall thickness (LV hypertrophy), and LV dilatation are the early macroscopic and functional alterations in obese developing heart failure. LV hypertrophy leads to diastolic dysfunction and subendocardial ischemia in obesity, and pericardial fat has been shown to be significantly associated with LV diastolic dysfunction. Evolving abnormalities of diastolic dysfunction may include progressive hypertrophy and systolic dysfunction, and various degrees of eccentric and/or concentric LV hypertrophy may be present with time. Once HF is established, overweight and obese have a better prognosis than do their lean counterparts with the same level of cardiovascular disease, and this phenomenon is called "obesity paradox". It is mainly due to lower muscle protein degradation, brain natriuretic peptide circulating levels and cardio-respiratory fitness than normal weight patients with HF.

Early Detection of Subclinical Uremic Cardiomyopathy Using Two-Dimensional Speckle Tracking Echocardiography.

PubMed

Hassanin, Noha; Alkemary, Alkhateeb

2016-04-01

Overhydration has a deleterious effect on cardio myocytes. This study was designated to evaluate left ventricular (LV) systolic and diastolic dysfunction in patients with various stages of chronic kidney disease (CKD) using conventional, tissue Doppler and two-dimensional speckle tracking echocardiography (2DSTE). Forty controls and 90 CKD patients, aged 49.3 ± 14 years old, were enrolled in the study. Patients were divided into 3 groups depending on their glomerular filtration rate. Group 1 (≥60 mL/min per 1.73 m(2) ), group 2 (≤60 mL/min per 1.73 m(2) ), and group 3 (≤60 mL/min per 1.73 m(2) and on regular dialysis for at least 12 months). Pulsed-Doppler and tissue Doppler studies were used to estimate LV filling pressure E/E'. Using 2DSTE, circumferential, radial, and longitudinal functions of the LV have been measured. LV longitudinal systolic strain, early, and late diastolic strain rates were significantly reduced in CKD patients (-16.9 ± 3.8%, 1.6 ± 0.5%, and 1.3 ± 0.4% in CKD vs. -22.5 ± 0.6%, 2.3 ± 0.2%, and 1.9 ± 0.1% in controls, P < 0.001 for all), and no difference was observed in terms of the circumferential LV functions (-22.4 ± 1.7 vs. -22.5 ± 1.4, P = 0.567). Severity of the kidney dysfunction appears to parallel with the rise of E/E' significantly (P < 0.001). In CKD, although the longitudinal and radial systolic functions were reduced, LV ejection fraction may remain within normal limits due to the preservation of the circumferential functions. Early detection of uremic cardiomyopathy might provide useful information for the risk stratification and decide the proper dialysis therapy in these patients. © 2015, Wiley Periodicals, Inc.

Quantifying subtle changes in cardiovascular mechanics in acromegaly: a Doppler myocardial imaging study.

PubMed

Jurcut, R; Găloiu, S; Florian, A; Vlădaia, A; Ioniţă, O R; Amzulescu, M S; Baciu, I; Popescu, B A; Coculescu, M; Ginghina, C

2014-11-01

To describe morphological and functional cardiovascular changes in acromegaly (ACM) patients, as well as to investigate the ability of Doppler-based myocardial deformation imaging (DMI) to characterize subtle dysfunction in ACM. 69 patients (pts) with ACM (mean age 47 ± 10 years, 27 men) and 31 controls (mean age 43 ± 16 years, matched for age and gender) were recruited. Standard echocardiography and DMI data were obtained for all patients. Peak systolic longitudinal strain values (S) were determined for the left and right ventricles. Radial S was measured at the level of the mid inferolateral segment. Using a high-resolution echo-tracking system, the main indices of arterial stiffness were measured. Of the ACM subjects, 57 had active disease (group A), and 12 controlled ACM (group B). All pts with ACM presented structural changes: a higher LV indexed mass (112 ± 36, 118 ± 23 vs 74 ± 18 g/m(2), p < 0.001) and a higher relative wall thickness (0.45 ± 0.09, 0.50 ± 0.07 vs 0.40 ± 0.07, p = 0.003) compared to controls. Also, ACM pts had functional changes: reduced LV ejection fraction (57 ± 5, 55 ± 5 vs 64 ± 4%, p < 0.001) and altered diastolic function (E/A 1.0 ± 0.4, 1.1 ± 0.1 vs 1.3 ± 0.3, p = 0.005) compared to controls. Both longitudinal and radial LV S values were lower in ACM compared to controls: -16.5 ± 3.5, -16.8 ± 4.3 vs -21.5 ± 3.8%, p < 0.001 for longitudinal and 38.3 ± 12.3, 35.6 ± 11.8 vs 52.2 ± 11.7%, p = 0.002 for radial strain. ACM pts present LV concentric hypertrophy and LV systolic and diastolic dysfunction, even in controlled disease. Altered global LV systolic function appears to be due both to longitudinal and radial dysfunction.

Genetic variants associated with cardiac structure and function: a meta-analysis and replication of genome-wide association data.

PubMed

Vasan, Ramachandran S; Glazer, Nicole L; Felix, Janine F; Lieb, Wolfgang; Wild, Philipp S; Felix, Stephan B; Watzinger, Norbert; Larson, Martin G; Smith, Nicholas L; Dehghan, Abbas; Grosshennig, Anika; Schillert, Arne; Teumer, Alexander; Schmidt, Reinhold; Kathiresan, Sekar; Lumley, Thomas; Aulchenko, Yurii S; König, Inke R; Zeller, Tanja; Homuth, Georg; Struchalin, Maksim; Aragam, Jayashri; Bis, Joshua C; Rivadeneira, Fernando; Erdmann, Jeanette; Schnabel, Renate B; Dörr, Marcus; Zweiker, Robert; Lind, Lars; Rodeheffer, Richard J; Greiser, Karin Halina; Levy, Daniel; Haritunians, Talin; Deckers, Jaap W; Stritzke, Jan; Lackner, Karl J; Völker, Uwe; Ingelsson, Erik; Kullo, Iftikhar; Haerting, Johannes; O'Donnell, Christopher J; Heckbert, Susan R; Stricker, Bruno H; Ziegler, Andreas; Reffelmann, Thorsten; Redfield, Margaret M; Werdan, Karl; Mitchell, Gary F; Rice, Kenneth; Arnett, Donna K; Hofman, Albert; Gottdiener, John S; Uitterlinden, Andre G; Meitinger, Thomas; Blettner, Maria; Friedrich, Nele; Wang, Thomas J; Psaty, Bruce M; van Duijn, Cornelia M; Wichmann, H-Erich; Munzel, Thomas F; Kroemer, Heyo K; Benjamin, Emelia J; Rotter, Jerome I; Witteman, Jacqueline C; Schunkert, Heribert; Schmidt, Helena; Völzke, Henry; Blankenberg, Stefan

2009-07-08

Echocardiographic measures of left ventricular (LV) structure and function are heritable phenotypes of cardiovascular disease. To identify common genetic variants associated with cardiac structure and function by conducting a meta-analysis of genome-wide association data in 5 population-based cohort studies (stage 1) with replication (stage 2) in 2 other community-based samples. Within each of 5 community-based cohorts comprising the EchoGen consortium (stage 1; n = 12 612 individuals of European ancestry; 55% women, aged 26-95 years; examinations between 1978-2008), we estimated the association between approximately 2.5 million single-nucleotide polymorphisms (SNPs; imputed to the HapMap CEU panel) and echocardiographic traits. In stage 2, SNPs significantly associated with traits in stage 1 were tested for association in 2 other cohorts (n = 4094 people of European ancestry). Using a prespecified P value threshold of 5 x 10(-7) to indicate genome-wide significance, we performed an inverse variance-weighted fixed-effects meta-analysis of genome-wide association data from each cohort. Echocardiographic traits: LV mass, internal dimensions, wall thickness, systolic dysfunction, aortic root, and left atrial size. In stage 1, 16 genetic loci were associated with 5 echocardiographic traits: 1 each with LV internal dimensions and systolic dysfunction, 3 each with LV mass and wall thickness, and 8 with aortic root size. In stage 2, 5 loci replicated (6q22 locus associated with LV diastolic dimensions, explaining <1% of trait variance; 5q23, 12p12, 12q14, and 17p13 associated with aortic root size, explaining 1%-3% of trait variance). We identified 5 genetic loci harboring common variants that were associated with variation in LV diastolic dimensions and aortic root size, but such findings explained a very small proportion of variance. Further studies are required to replicate these findings, identify the causal variants at or near these loci, characterize their functional significance, and determine whether they are related to overt cardiovascular disease.

High-sensitive cardiac Troponin T is superior to echocardiography in predicting 1-year mortality in patients with SIRS and shock in intensive care.

PubMed

Bergenzaun, Lill; Ohlin, Hans; Gudmundsson, Petri; Düring, Joachim; Willenheimer, Ronnie; Chew, Michelle S

2012-09-24

Left ventricular (LV) dysfunction is well documented in the critically ill. We assessed 1-year mortality in relation to cardiac biomarkers and LV function parameters by echocardiography in patients with shock. A prospective, observational, cohort study of 49 patients. B-natriuretic peptide (BNP), high-sensitive troponin T (hsTNT) and transthoracic echocardiography (TTE) were assessed within 12 h of study inclusion. LV systolic function was measured by ejection fraction (LVEF), mean atrioventricular plane displacement (AVPDm), peak systolic tissue Doppler velocity imaging (TDIs) and velocity time integral in the LV outflow tract (LVOT VTI). LV diastolic function was evaluated by transmitral pulsed Doppler (E, A, E/A, E-deceleration time), tissue Doppler indices (é, á, E/é) and left atrial volume (La volume). APACHE II (Acute Physiology and Chronic Health Evaluation) and SOFA (Sequential Organ Failure Assessment) scores were calculated. hsTNT was significantly higher in non-survivors than in survivors (60 [17.0-99.5] vs 168 [89.8-358] ng/l, p = 0.003). Other univariate predictors of mortality were APACHE II (p = 0.009), E/é (p = 0.023), SOFA (p = 0.024) and age (p = 0.031). Survivors and non-survivors did not differ regarding BNP (p = 0.26) or any LV systolic function parameter (LVEF p = 0.87, AVPDm p = 0.087, TDIs p = 0.93, LVOT VTI p = 0.18). Multivariable logistic regression analysis identified hsTNT (p = 0.010) as the only independent predictor of 1-year mortality; adjusted odds ratio 2.0 (95% CI 1.2- 3.5). hsTNT was the only independent predictor of 1-year mortality in patients with shock. Neither BNP nor echocardiographic parameters had an independent prognostic value. Further studies are needed to establish the clinical significance of elevated hsTNT in patients in shock.

Functional tricuspid regurgitation and the right ventricle: What we do not know is more than we know.

PubMed

Calafiore, Antonio Maria; Bartoloni, Giovanni; Al Amri, Hussein; Iacò, Angela Lorena; Abukhudair, Walid; Lanzaro, Bianca Iadanza; Di Mauro, Michele

2012-11-01

The tricuspid valve (TV) lies in between the right atrium and the right ventricle (RV), consisting of annulus, leaflets, chords and papillary muscles. The RV appears triangular-shaped in a lateral view and crescent-shaped in a cross-section one. In normal conditions, the septum is concave toward the left ventricle (LV) in both systole and diastole and the RV volume is larger than the LV volume, although its mass is a third of the LV. The strict relationship between the TV apparatus and the RV underlies the physiological mechanism of TV functioning, and so, the RV plays an important role in case of functional tricuspid regurgitation. Nevertheless, the systematic assessment of RV is still not performed mainly due to lack of standardization. Hence, new echocardiographic guidelines have recently been proposed to standardize the RV assessment using transthoracic 2D‑echocardiography. 3D-echocardiography and MRI are more useful to measure volumes and ejection fraction; in particular, MRI is able to provide a tissue evaluation. Today, surgical strategies are directed mainly to the annulus with fluctuating results because functional tricuspid regurgitation is not due only to the annulus but also to the RV, which is difficult to assess, due to its evolution being unpredictable and complicated by the interaction with LV.

Limitations of expressing left ventricular mass relative to height and to body surface area in children.

PubMed

Foster, Bethany J; Gao, Tao; Mackie, Andrew S; Zemel, Babette S; Ali, Huma; Platt, Robert W; Colan, Steven D

2013-04-01

Left ventricular (LV) mass varies in proportion to lean body mass (LBM) but is usually expressed relative to height or body surface area (BSA), each of which functions as a surrogate for LBM. The aims of this study were to characterize the adiposity-related biases associated with each of these scaling variables and to determine the impact of these biases on the diagnosis of LV hypertrophy (LVH) in a group of children at risk for LVH. In a retrospective study, LV mass was estimated using M-mode echocardiography in 222 healthy nonoverweight reference children and 112 children "at risk" for LVH (48 healthy overweight children and 64 children with hypertension). LBM was estimated for all children using validated predictive equations and was considered the criterion scaling variable. Z scores for LV mass for LBM, LV mass for height, and LV mass for BSA were calculated for each child relative to the reference group. The performance of height-based and BSA-based Z scores were compared with that of LBM-based Z scores at different levels of adiposity (estimated by the Z score for body mass index for age [BMIz]). Among healthy normotensive children, LV mass-for-height Z scores were greater than LV mass-for-LBM Z scores at higher values of BMIz and lower than LV mass-for-LBM Z scores at lower values of BMIz (R(2) = 0.52, P < .0001). LV mass-for-BSA Z scores for agreed well with LBM-based Z scores at BMIz < 0.7 but were lower than LV mass-for-LBM Z scores for at BMIz > 0.7 (R(2) = 0.31, P < .0001). Compared with 13% of at-risk children classified as having LVH on the basis of LV mass for LBM > 95th percentile, 30% and 11% had LVH when LV mass was scaled to height and BSA, respectively. Scaling LV mass to BSA in children results in less misclassification with respect to LVH than does scaling to height. Copyright © 2013 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

Heart disease and left ventricular rotation - a systematic review and quantitative summary.

PubMed

Phillips, Aaron A; Cote, Anita T; Bredin, Shannon S D; Warburton, Darren E R

2012-06-24

Left ventricular (LV) rotation is increasingly examined in those with heart disease. The available evidence measuring LV rotation in those with heart diseases has not been systematically reviewed. To review systematically the evidence measuring LV rotational changes in various heart diseases compared to healthy controls, literature searches were conducted for appropriate articles using several electronic databases (e.g., MEDLINE, EMBASE). All randomized-controlled trials, prospective cohort and case-controlled studies that assessed LV rotation in relation to various heart conditions were included. Three independent reviewers evaluated each investigation's quality using validated scales. Results were tabulated and levels of evidence assigned. A total of 1,782 studies were found through the systematic literature search. Upon review of the articles, 47 were included. The articles were separated into those investigating changes in LV rotation in participants with: aortic stenosis, myocardial infarction, hypertrophic cardiomyopathy, dilated cardiomyopathy, non-compaction, restrictive cardiomyopathy/ constrictive pericarditis, heart failure, diastolic dysfunction, heart transplant, implanted pacemaker, coronary artery disease and cardiovascular disease risk factors. Evidence showing changes in LV rotation due to various types of heart disease was supported by evidence with limited to moderate methodological quality. Despite a relatively low quality and volume of evidence, the literature consistently shows that heart disease leads to marked changes in LV rotation, while rotational systolic-diastolic coupling is preserved. No prognostic information exists on the potential value of rotational measures of LV function. The literature suggests that measures of LV rotation may aid in diagnosing subclinical aortic stenosis and diastolic dysfunction.

Astakine LvAST binds to the β subunit of F1-ATP synthase and likely plays a role in white shrimp Litopeneaus vannamei defense against white spot syndrome virus.

PubMed

Liang, Gao-Feng; Liang, Yan; Xue, Qinggang; Lu, Jin-Feng; Cheng, Jun-Jun; Huang, Jie

2015-03-01

Cytokines play a critical role in innate and adaptive immunity. Astakines represent a group of invertebrate cytokines that are related to vertebrate prokineticin and function in promoting hematopoiesis in crustaceans. We have identified an astakine from the white shrimp Litopeneaus vannamei and named it LvAST in a previous research. In the present research, we investigated the interactions among LvAST, the envelope protein VP37 of white spot syndrome virus (i.e., WSSV), and the β subunit of F1-ATP synthase (ATPsyn-β) of the white shrimp (i.e., BP53) using binding assays and co-precipitations. We also examined the effects of LvAST on shrimp susceptibility to WSSV. We found that LvAST and VP37 competitively bound to BP53, but did not bind to each other. Shrimps that had been injected with recombinant LvAST exhibited significantly lower mortality and longer survival time in experimental infections by WSSV. In contrast, shrimps whose LvAST gene expression had been inhibited by RNA interference showed significantly higher WSSV infection intensity and shorter survival time following viral challenges. These results suggested that LvAST and WSSV both likely use ATPsyn-β as a receptor and LvAST plays a role in shrimp defense against WSSV infection. This represented the first research showing the involvement of astakines in host antiviral immunity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Timing effect of intramyocardial hydrogel injection for positively impacting left ventricular remodeling after myocardial infarction

PubMed Central

Yoshizumi, Tomo; Zhu, Yang; Jiang, Hongbin; D’Amore, Antonio; Sakaguchi, Hirokazu; Tchao, Jason; Tobita, Kimimasa; Wagner, William R.

2016-01-01

Intramyocardial injection of various injectable hydrogel materials has shown benefit in positively impacting the course of left ventricular (LV) remodeling after myocardial infarction (MI). However, since LV remodeling is a complex, time dependent process, the most efficacious time of hydrogel injection is not clear. In this study, we injected a relatively stiff, thermoresponsive and bioabsorbable hydrogel in rat hearts at 3 different time points - immediately after MI (IM), 3 d post-MI (3D), and 2 w post-MI (2W), corresponding to the beginnings of the necrotic, fibrotic and chronic remodeling phases. The employed left anterior descending coronary artery ligation model showed expected infarction responses including functional loss, inflammation and fibrosis with distinct time dependent patterns. Changes in LV geometry and contractile function were followed by longitudinal echocardiography for 10 w post-MI. While all injection times positively affected LV function and wall thickness, the 3D group gave better functional outcomes than the other injection times and also exhibited more local vascularization and less inflammatory markers than the earlier injection time. The results indicate an important role for injection timing in the increasingly explored concept of post-MI biomaterial injection therapy and suggest that for hydrogels with mechanical support as primary function, injection at the beginning of the fibrotic phase may provide improved outcomes. PMID:26774561

Timing effect of intramyocardial hydrogel injection for positively impacting left ventricular remodeling after myocardial infarction.

PubMed

Yoshizumi, Tomo; Zhu, Yang; Jiang, Hongbin; D'Amore, Antonio; Sakaguchi, Hirokazu; Tchao, Jason; Tobita, Kimimasa; Wagner, William R

2016-03-01

Intramyocardial injection of various injectable hydrogel materials has shown benefit in positively impacting the course of left ventricular (LV) remodeling after myocardial infarction (MI). However, since LV remodeling is a complex, time dependent process, the most efficacious time of hydrogel injection is not clear. In this study, we injected a relatively stiff, thermoresponsive and bioabsorbable hydrogel in rat hearts at 3 different time points - immediately after MI (IM), 3 d post-MI (3D), and 2 w post-MI (2W), corresponding to the beginnings of the necrotic, fibrotic and chronic remodeling phases. The employed left anterior descending coronary artery ligation model showed expected infarction responses including functional loss, inflammation and fibrosis with distinct time dependent patterns. Changes in LV geometry and contractile function were followed by longitudinal echocardiography for 10 w post-MI. While all injection times positively affected LV function and wall thickness, the 3D group gave better functional outcomes than the other injection times and also exhibited more local vascularization and less inflammatory markers than the earlier injection time. The results indicate an important role for injection timing in the increasingly explored concept of post-MI biomaterial injection therapy and suggest that for hydrogels with mechanical support as primary function, injection at the beginning of the fibrotic phase may provide improved outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Angiotensin-converting enzyme and matrix metalloproteinase inhibition with developing heart failure: comparative effects on left ventricular function and geometry

NASA Technical Reports Server (NTRS)

McElmurray, J. H. 3rd; Mukherjee, R.; New, R. B.; Sampson, A. C.; King, M. K.; Hendrick, J. W.; Goldberg, A.; Peterson, T. J.; Hallak, H.; Zile, M. R.;

Protease-Activated Receptor 1 Inhibition by SCH79797 Attenuates Left Ventricular Remodeling and Profibrotic Activities of Cardiac Fibroblasts

PubMed Central

Sonin, Dmitry L.; Wakatsuki, Tetsuro; Routhu, Kasi V.; Harmann, Leanne M.; Petersen, Matthew; Meyer, Jennifer; Strande, Jennifer L.

2013-01-01

Purpose Fibroblast activity promotes adverse left ventricular (LV) remodeling that underlies the development of ischemic cardiomyopathy. Transforming growth factor-β (TGF-β) is a potent stimulus for fibrosis, and the extracellular signal-regulated kinases(ERK) 1/2 pathway also contributes to the fibrotic response. The thrombin receptor, protease-activated receptor 1 (PAR1), has been shown to play an important role in the excessive fibrosis in different tissues. The aim of this study was to investigate the influence of a PAR1 inhibitor, SCH79797, on cardiac fibrosis, tissue stiffness and postinfarction remodeling, and effects of PAR1 inhibition on thrombin-induced TGF-β and (ERK) 1/2 activities in cardiac fibroblasts. Methods We used a rat model of myocardial ischemia–reperfusion injury, isolated cardiac fibroblasts, and 3-dimensional (3D) cardiac tissue models fabricated to ascertain the contribution of PAR1 activation on cardiac fibrosis and LV remodeling. Results The PAR1 inhibitor attenuated LV dilation and improved LV systolic function of the reperfused myocardium at 28 days. This improvement was associated with a nonsignificant decrease in scar size (%LV) from 23 ± % in the control group (n = 10) to 16% ± 5.5% in the treated group (n = 9; P = .052). In the short term, the PAR1 inhibitor did not rescue infarct size or LV systolic function after 3 days. The PAR1 inhibition abolished thrombin-mediated ERK1/2 phosphorylation, TGF-β and type I procollagen production, matrix metalloproteinase-2/9 activation, myofibroblasts transformation in vitro, and abrogated the remodeling of 3D tissues induced by chronic thrombin treatment. Conclusion These studies suggest PAR1 inhibition initiated after ischemic injury attenuates adverse LV remodeling through late-stage antifibrotic events. PMID:23598708

Dissociation between cardiomyocyte function and remodeling with beta-adrenergic receptor blockade in isolated canine mitral regurgitation.

PubMed

Pat, Betty; Killingsworth, Cheryl; Denney, Thomas; Zheng, Junying; Powell, Pamela; Tillson, Michael; Dillon, A Ray; Dell'Italia, Louis J

2008-12-01

The low-pressure volume overload of isolated mitral regurgitation (MR) is associated with increased adrenergic drive, left ventricular (LV) dilatation, and loss of interstitial collagen. We tested the hypothesis that beta1-adrenergic receptor blockade (beta1-RB) would attenuate LV remodeling after 4 mo of MR in the dog. beta1-RB did not attenuate collagen loss or the increase in LV mass in MR dogs. Using MRI and three-dimensional (3-D) analysis, there was a 70% increase in the LV end-diastolic (LVED) volume-to-LV mass ratio, a 23% decrease in LVED midwall circumferential curvature, and a >50% increase in LVED 3-D radius/wall thickness in MR dogs that was not attenuated by beta1-RB. However, beta1-RB caused a significant increase in LVED length from the base to apex compared with untreated MR dogs. This was associated with an increase in isolated cardiomyocyte length (171+/-5 microm, P<0.05) compared with normal (156+/-3 microm) and MR (165+/-4 microm) dogs. Isolated cardiomyocyte fractional shortening was significantly depressed in MR dogs compared with normal dogs (3.73+/-0.31 vs. 5.02+/-0.26%, P<0.05) and normalized with beta1-RB (4.73+/-0.48%). In addition, stimulation with the beta-adrenergic receptor agonist isoproterenol (25 nM) increased cardiomyocyte fractional shortening by 215% (P<0.05) in beta1-RB dogs compared with normal (56%) and MR (50%) dogs. In summary, beta1-RB improved LV cardiomyocyte function and beta-adrenergic receptor responsiveness despite further cell elongation. The failure to attenuate LV remodeling associated with MR could be due to a failure to improve ultrastructural changes in extracellular matrix organization.

Chymase inhibition prevents fibronectin and myofibrillar loss and improves cardiomyocyte function and LV torsion angle in dogs with isolated mitral regurgitation.

PubMed

Pat, Betty; Chen, Yuanwen; Killingsworth, Cheryl; Gladden, James D; Shi, Ke; Zheng, Junying; Powell, Pamela C; Walcott, Greg; Ahmed, Mustafa I; Gupta, Himanshu; Desai, Ravi; Wei, Chih-Chang; Hase, Naoki; Kobayashi, Tsunefumi; Sabri, Abdelkarim; Granzier, Henk; Denney, Thomas; Tillson, Michael; Dillon, A Ray; Husain, Ahsan; Dell'italia, Louis J

2010-10-12

The left ventricular (LV) dilatation of isolated mitral regurgitation (MR) is associated with an increase in chymase and a decrease in interstitial collagen and extracellular matrix. In addition to profibrotic effects, chymase has significant antifibrotic actions because it activates matrix metalloproteinases and kallikrein and degrades fibronectin. Thus, we hypothesize that chymase inhibitor (CI) will attenuate extracellular matrix loss and LV remodeling in MR. We studied dogs with 4 months of untreated MR (MR; n=9) or MR treated with CI (MR+CI; n=8). Cine MRI demonstrated a >40% increase in LV end-diastolic volume in both groups, consistent with a failure of CI to improve a 25% decrease in interstitial collagen in MR. However, LV cardiomyocyte fractional shortening was decreased in MR versus normal dogs (3.71±0.24% versus 4.81±0.31%; P<0.05) and normalized in MR+CI dogs (4.85±0.44%). MRI with tissue tagging demonstrated an increase in LV torsion angle in MR+CI versus MR dogs. CI normalized the significant decrease in fibronectin and FAK phosphorylation and prevented cardiomyocyte myofibrillar degeneration in MR dogs. In addition, total titin and its stiffer isoform were increased in the LV epicardium and paralleled the changes in fibronectin and FAK phosphorylation in MR+CI dogs. These results suggest that chymase disrupts cell surface-fibronectin connections and FAK phosphorylation that can adversely affect cardiomyocyte myofibrillar structure and function. The greater effect of CI on epicardial versus endocardial titin and noncollagen cell surface proteins may be responsible for the increase in torsion angle in chronic MR.

Renal Sympathetic Denervation in Rats Ameliorates Cardiac Dysfunction and Fibrosis Post-Myocardial Infarction Involving MicroRNAs

PubMed Central

Zheng, Xiaoxin; Li, Xiaoyan; Lyu, Yongnan; He, Yiyu; Wan, Weiguo; Jiang, Xuejun

2016-01-01

Background The role of renal sympathetic denervation (RSD) in ameliorating post-myocardial infarction (MI) left ventricular (LV) fibrosis via microRNA-dependent regulation of connective tissue growth factor (CTGF) remains unknown. Material/Methods MI and RSD were induced in Sprague–Dawley rats by ligating the left coronary artery and denervating the bilateral renal nerves, respectively. Norepinephrine, renin, angiotensin II and aldosterone in plasma, collagen, microRNA21, microRNA 101a, microRNA 133a and CTGF in heart tissue, as well as cardiac function were evaluated six weeks post-MI. Results In the RSD group, parameters of cardiac function were significantly improved as evidenced by increased LV ejection fraction (p<0.01), LV end-systolic diameter (p<0.01), end-diastolic diameter (p<0.05), LV systolic pressure (p<0.05), maximal rate of pressure rise and decline (dP/dtmax and dP/dtmin, p<0.05), and decreased LV end-diastolic pressure (p<0.05) when compared with MI rats. Further, reduced collagen deposition in peri-infarct myocardium was observed in RSD-treated rats along with higher microRNA101a and microRNA133a (p<0.05) and lower microRNA21 expression (p<0.01) than in MI rats. CTGF mRNA and protein levels were decreased in LV following RSD (p<0.01), accompanied by decreased expression of norepinephrine, renin, angiotensin II and aldosterone in plasma (p<0.05) compared with untreated MI rats. Conclusions The potential therapeutic effects of RSD on post-MI LV fibrosis may be partly mediated by inhibition of CTGF expression via upregulation of microRNA 101a and microRNA 133a and downregulation of microRNA21. PMID:27490896

The influence of right ventricular stimulation on acute response to cardiac resynchronisation therapy.

PubMed

Wu, L; de Roest, G J; Hendriks, M L; van Rossum, A C; de Cock, C C; Allaart, C P

2016-01-01

The contribution of right ventricular (RV) stimulation to cardiac resynchronisation therapy (CRT) remains controversial. RV stimulation might be associated with adverse haemodynamic effects, dependent on intrinsic right bundle branch conduction, presence of scar, RV function and other factors which may partly explain non-response to CRT. This study investigates to what degree RV stimulation modulates response to biventricular (BiV) stimulation in CRT candidates and which baseline factors, assessed by cardiac magnetic resonance imaging, determine this modulation. Forty-one patients (24 (59 %) males, 67 ± 10 years, QRS 153 ± 22 ms, 21 (51 %) ischaemic cardiomyopathy, left ventricular (LV) ejection fraction 25 ± 7 %), who successfully underwent temporary stimulation with pacing leads in the RV apex (RVapex) and left ventricular posterolateral (PL) wall were included. Stroke work, assessed by a conductance catheter, was used to assess acute haemodynamic response during baseline conditions and RVapex, PL (LV) and PL+RVapex (BiV) stimulation. Compared with baseline, stroke work improved similarly during LV and BiV stimulation (∆+ 51 ± 42 % and ∆+ 48 ± 47 %, both p < 0.001), but individual response showed substantial differences between LV and BiV stimulation. Multivariate analysis revealed that RV ejection fraction (β = 1.01, p = 0.02) was an independent predictor for stroke work response during LV stimulation, but not for BiV stimulation. Other parameters, including atrioventricular delay and scar presence and localisation, did not predict stroke work response in CRT. The haemodynamic effect of addition of RVapex stimulation to LV stimulation differs widely among patients receiving CRT. Poor RV function is associated with poor response to LV but not BiV stimulation.

Downregulation of cardiac guanosine 5'-triphosphate-binding proteins in right atrium and left ventricle in pacing-induced congestive heart failure.

PubMed Central

Roth, D A; Urasawa, K; Helmer, G A; Hammond, H K

1993-01-01

The extent to which congestive heart failure (CHF) is dependent upon increased levels of the cardiac inhibitory GTP-binding protein (Gi), and the impact of CHF on the cardiac stimulatory GTP-binding protein (Gs) and mechanisms by which Gs may change remain unexplored. We have addressed these unsettled issues using pacing-induced CHF in pigs to examine physiological, biochemical, and molecular features of the right atrium (RA) and left ventricle (LV). CHF was associated with an 85 +/- 20% decrease in LV segment shortening (P < 0.001) and a 3.5-fold increase (P = 0.006) in the ED50 for isoproterenol-stimulated heart rate responsiveness. Myocardial beta-adrenergic receptor number was decreased 54% in RA (P = 0.004) and 57% in LV (P < 0.001), and multiple measures of adenylyl cyclase activity were depressed 49 +/- 8% in RA (P < 0.005), and 44 +/- 9% in LV (P < 0.001). Quantitative immunoblotting established that Gi and Gs were decreased in RA (Gi: 59% reduction; P < 0.0001; Gs: 28% reduction; P < 0.007) and LV (Gi: 35% reduction; P < 0.008; Gs: 28% reduction; P < 0.01) after onset of CHF. Reduced levels of Gi and Gs were confirmed by ADP ribosylation studies, and diminished function of Gs was established in reconstitution studies. Steady state levels for Gs alpha mRNA were increased in RA and unchanged in LV, and significantly more GS alpha was found in the supernatant (presumably cytosolic) fraction in RA and LV membrane homogenates after CHF, suggesting that increased Gs degradation, rather than decreased Gs synthesis, is the mechanism by which Gs is downregulated. We conclude that cardiac Gi content poorly predicts adrenergic responsiveness or contractile function, that decreased Gs is caused by increased degradation rather than decreased synthesis, and that alterations in beta-adrenergic receptors, adenylyl cyclase, and GTP-binding proteins are uniform in RA and LV in this model of congestive heart failure. Images PMID:8383705

Relationship between Myocardial Extracellular Space Expansion Estimated with Post-Contrast T1 Mapping MRI and Left Ventricular Remodeling and Neurohormonal Activation in Patients with Dilated Cardiomyopathy.

PubMed

Yoon, Ji Hyun; Son, Jung Woo; Chung, Hyemoon; Park, Chul Hwan; Kim, Young-Jin; Chang, Hyuk-Jae; Hong, Geu-Ru; Kim, Tae Hoon; Ha, Jong-Won; Choi, Byoung Wook; Rim, Se-Joong; Chung, Namsik; Choi, Eui-Young

2015-01-01

Post-contrast T1 values are closely related to the degree of myocardial extracellular space expansion. We determined the relationship between post-contrast T1 values and left ventricular (LV) diastolic function, LV remodeling, and neurohormonal activation in patients with dilated cardiomyopathy (DCM). Fifty-nine patients with DCM (mean age, 55 ± 15 years; 41 males and 18 females) who underwent both 1.5T magnetic resonance imaging and echocardiography were enrolled. The post-contrast 10-minute T1 value was generated from inversion time scout images obtained using the Look-Locker inversion recovery sequence and a curve-fitting algorithm. The T1 sample volume was obtained from three interventricular septal points, and the mean T1 value was used for analysis. The N-Terminal pro-B-type natriuretic peptide (NT-proBNP) level was measured in 40 patients. The mean LV ejection fraction was 24 ± 9% and the post-T1 value was 254.5 ± 46.4 ms. The post-contrast T1 value was significantly correlated with systolic longitudinal septal velocity (s'), peak late diastolic velocity of the mitral annulus (a'), the diastolic elastance index (Ed, [E/e']/stroke volume), LV mass/volume ratio, LV end-diastolic wall stress, and LV end-systolic wall stress. In a multivariate analysis without NT-proBNP, T1 values were independently correlated with Ed (β = -0.351, p = 0.016) and the LV mass/volume ratio (β = 0.495, p = 0.001). When NT-proBNP was used in the analysis, NT-proBNP was independently correlated with the T1 values (β = -0.339, p = 0.017). Post-contrast T1 is closely related to LV remodeling, diastolic function, and neurohormonal activation in patients with DCM.

The microvascular effects of insulin resistance and diabetes on cardiac structure, function, and perfusion: a cardiovascular magnetic resonance study.

PubMed

Larghat, Abdulghani M; Swoboda, Peter P; Biglands, John D; Kearney, Mark T; Greenwood, John P; Plein, Sven

2014-12-01

Type 2 diabetes mellitus is an independent risk factor for the development of heart failure. To better understand the mechanism by which this occurs, we investigated cardiac structure, function, and perfusion in patients with and without diabetes. Sixty-five patients with no stenosis >30% on invasive coronary angiography were categorized into diabetes (19) and non-diabetes (46) which was further categorized into prediabetes (30) and controls (16) according to the American Diabetes Association guidelines. Each patient underwent comprehensive cardiovascular magnetic resonance assessment. Left-ventricular (LV) mass, relative wall mass (RWM), Lagrangian circumferential strain, LV torsion, and myocardial perfusion reserve (MPR) were calculated. LV mass was higher in diabetics than non-diabetics (112.8 ± 39.7 vs. 91.5 ± 21.3 g, P = 0.01) and in diabetics than prediabetics (112.8 ± 39.7 vs. 90.3 ± 18.7 g, P = 0.02). LV torsion angle was higher in diabetics than non-diabetics (9.65 ± 1.90 vs. 8.59 ± 1.91°, P = 0.047), and MPR was lower in diabetics than non-diabetics (2.10 ± 0.76 vs. 2.84 ± 1.25 mL/g/min, P = 0.01). There was significant correlation between MPR and early diastolic strain rate (r = -0.310, P = 0.01) and LV torsion (r = -0.306, P = 0.01). In multivariable linear regression analysis, non-diabetics waist-hip ratio, but not body mass index, had a significant association with RWM (Beta = 0.34, P = 0.02). Patients with diabetes have increased LV mass, LV torsion, and decreased MPR. There is a significant association between decreased MPR and increased LV torsion suggesting a possible mechanistic link between microvascular disease and cardiac dysfunction in diabetes. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Cardiology.

Particle tracking velocimetry using echocardiographic data resolves flow in the left ventricle

NASA Astrophysics Data System (ADS)

Sampath, Kaushik; Abd, Thura T.; George, Richard T.; Katz, Joseph

2015-11-01

Two dimensional contrast echocardiography was performed on patients with a history of left ventricular (LV) thrombus. The 636 x 434 pixels electrocardiograms were recorded using a GE Vivid 9E system with (M5S-D and 4V-D) probes in a 2-D mode at a magnification of 0.3 mm/pix. The concentration of 2-4.5 micron seed bubbles was adjusted to obtain individually discernable traces, and a data acquisition rate of 60-90 fps kept the inter-frame displacements suitable for matching traces, and calculating vectors, but yet low enough to allow a scanning depth and width of upto 13 cm and 60 degrees respectively. Particle tracking velocimetry (PTV) guided by initial particle image velocimetry (PIV) was used to obtain the velocity distributions inside the LV with vector spacing of 3-5 mm. The data quality was greatly enhanced by implementing an iterative particle specific enhancement and tracking algorithm. Data covering 20 heart beats facilitated phase averaging. The results elucidated blood flow in the intra-ventricular septal region, lateral wall region, the apex of the LV and the mitral valve region.

Telmisartan regresses left ventricular hypertrophy in caveolin-1 deficient mice

PubMed Central

Kreiger, Marta H; Di Lorenzo, Annarita; Teutsch, Christine; Kauser, Katalin; Sessa, William C.

2011-01-01

The role of angiotensin II (Ang II) in promoting cardiac hypertrophy is well known, however the role of the Ang II in a spontaneous model of hypertrophy in mice lacking the protein caveolin-1 (Cav- KO) has not been explored. In this study, WT and Cav-1 KO mice were treated with angiotensin receptor blocker (ARB), telmisartan, and cardiac function assessed by echocardiography. Treatment of Cav-1 KO mice with telmisartan significantly improved cardiac function compared to age-matched, vehicle treated Cav-1 KO mice, while telmisartan did not affected cardiac function in WT mice. Both left ventricular (LV) weight to body weight ratios and LV to tibial length ratios were also reverted by telmisartan in Cav-1 KO but not WT mice. LV hypertrophy was associated with increased expression of natriuretic peptides-A and –B, β-myosin heavy chain and TGF-β and telmisartan treatment normalized the expression of these genes. Telmisartan reduced the expression of collagen genes (Col1A and Col3A) and associated perivascular fibrosis in intramyocardial vessels in Cav-1 KO mice. In conclusion, telmisartan treatment reduces indexes of cardiac hypertrophy in this unique genetic model of spontaneous LV hypertrophy. PMID:20585312

Accuracy of right and left ventricular functional assessment by short-axis vs axial cine steady-state free-precession magnetic resonance imaging: intrapatient correlation with main pulmonary artery and ascending aorta phase-contrast flow measurements.

PubMed

James, Susan H; Wald, Rachel; Wintersperger, Bernd J; Jimenez-Juan, Laura; Deva, Djeven; Crean, Andrew M; Nguyen, Elsie; Paul, Narinder S; Ley, Sebastian

2013-08-01

The left ventricle (LV) is routinely assessed with cardiac magnetic resonance imaging (MRI) by using short-axis orientation; it remains unclear whether the right ventricle (RV) can also be adequately assessed in this orientation or whether dedicated axial orientation is required. We used phase-contrast (PC) flow measurements in the main pulmonary artery (MPA) and the ascending aorta (Aorta) as nonvolumetric standard of reference and compared RV and LV volumes in short-axis and axial orientations. A retrospective analysis identified 30 patients with cardiac MRI data sets. Patients underwent MRI (1.5 T or 3 T), with retrospectively gated cine steady-state free-precession in axial and short-axis orientations. PC flow analyses of MPA and Aorta were used as the reference measure of RV and LV output. There was a high linear correlation between MPA-PC flow and RV-stroke volume (SV) short axis (r = 0.9) and RV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 1.4 mL for RV axial and -2.3 mL for RV-short-axis vs MPA-PC flow. There was a high linear correlation between Aorta-PC flow and LV-SV short-axis (r = 0.9) and LV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 4.8 m for LV short axis and 7.0 mL for LV axial vs Aorta-PC flow. There was no significant difference (P = .6) between short-axis-LV SV and short-axis-RV SV. No significant impact of the slice acquisition orientation for determination of RV and LV stroke volumes was found. Therefore, cardiac magnetic resonance workflow does not need to be extended by an axial data set for patients without complex cardiac disease for assessment of biventricular function and volumes. Copyright © 2013 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

A chitinase from pacific white shrimp Litopenaeus vannamei involved in immune regulation.

PubMed

Niu, Shengwen; Yang, Linwei; Zuo, Hongliang; Zheng, Jiefu; Weng, Shaoping; He, Jianguo; Xu, Xiaopeng

2018-08-01

Chitinases are a group of hydrolytic enzymes that hydrolyze chitin and widely exist in organisms. Studies in mammals have demonstrated that chitinases play important roles in regulation of humoral and cellular immune responses. In arthropods, although it is well known that chitinases are involved in growth, molting and development, the current knowledge on the role of chitinases in immunity, especially in immune regulation, remains largely unknown. In this study, a chitinase (LvChi5) from Litopenaeus vannamei was representatively selected for studying its immune function. The start codon of LvChi5 was corrected by 5'RACE analysis and its protein sequence was reanalyzed. LvChi5 contains a catalytic domain and a chitin binding domain and shows no inhibitory effect on growth of bacteria in vitro. However, in vivo experiments demonstrated that silencing of LvChi5 increased the mortality of shrimp infected with white spot syndrome virus (WSSV) and Vibro parahaemolyticus and significantly upregulated the load of pathogens in tissues. The expression of various immune related genes, including transcription factors, antimicrobial peptides and other functional proteins with antibacterial and antiviral activities, was widely changed in LvChi5 silencing shrimp. Moreover, the recombinant LvChi5 protein could enhance the phagocytic activity of hemocytes against bacteria. These suggested that shrimp chitinase could play a role in regulation of both humoral and cellular immune responses in shrimp. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hippocampal Insulin Resistance Impairs Spatial Learning and Synaptic Plasticity.

PubMed

Grillo, Claudia A; Piroli, Gerardo G; Lawrence, Robert C; Wrighten, Shayna A; Green, Adrienne J; Wilson, Steven P; Sakai, Randall R; Kelly, Sandra J; Wilson, Marlene A; Mott, David D; Reagan, Lawrence P

2015-11-01

Insulin receptors (IRs) are expressed in discrete neuronal populations in the central nervous system, including the hippocampus. To elucidate the functional role of hippocampal IRs independent of metabolic function, we generated a model of hippocampal-specific insulin resistance using a lentiviral vector expressing an IR antisense sequence (LV-IRAS). LV-IRAS effectively downregulates IR expression in the rat hippocampus without affecting body weight, adiposity, or peripheral glucose homeostasis. Nevertheless, hippocampal neuroplasticity was impaired in LV-IRAS-treated rats. High-frequency stimulation, which evoked robust long-term potentiation (LTP) in brain slices from LV control rats, failed to evoke LTP in LV-IRAS-treated rats. GluN2B subunit levels, as well as the basal level of phosphorylation of GluA1, were reduced in the hippocampus of LV-IRAS rats. Moreover, these deficits in synaptic transmission were associated with impairments in spatial learning. We suggest that alterations in the expression and phosphorylation of glutamate receptor subunits underlie the alterations in LTP and that these changes are responsible for the impairment in hippocampal-dependent learning. Importantly, these learning deficits are strikingly similar to the impairments in complex task performance observed in patients with diabetes, which strengthens the hypothesis that hippocampal insulin resistance is a key mediator of cognitive deficits independent of glycemic control. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Echocardiographic phase imaging to predict reverse remodeling after cardiac resynchronization therapy.

PubMed

Buss, Sebastian J; Humpert, Per M; Bekeredjian, Raffi; Hardt, Stefan E; Zugck, Christian; Schellberg, Dieter; Bauer, Alexander; Filusch, Arthur; Kuecherer, Helmut; Katus, Hugo A; Korosoglou, Grigorios

2009-05-01

The aim of our study was to investigate whether echocardiographic phase imaging (EPI) can predict response in patients who are considered for cardiac resynchronization therapy (CRT). CRT improves quality of life, exercise capacity, and outcome in patients with bundle-branch block and advanced heart failure. Previous studies used QRS duration to select patients for CRT; the accuracy of this parameter to predict functional recovery, however, is controversial. We examined 42 patients with advanced heart failure (New York Heart Association [NYHA] functional class III to IV, QRS duration >130 ms, and ejection fraction <35%) before and 6 to 8 months after CRT. Left ventricular (LV) dyssynchrony was estimated by calculating the SD of time to peak velocities (Ts-SD) by conventional tissue Doppler imaging (TDI), and the mean phase index (mean EPI-Index) was calculated by EPI in 12 mid-ventricular and basal segments. Patients who were alive and had significant relative decrease in end-systolic LV volume of Delta ESV >or=15% at 6 to 8 months of follow-up were defined as responders. All others were classified as nonresponders. The Ts-SD and the mean EPI-Index were related to Delta ESV (r = 0.43 for Ts-SD and r = 0.67 for mean EPI-Index, p < 0.01 for both), and both parameters yielded similar accuracy for the prediction of LV remodeling (area under the curve of 0.87 for TDI vs. 0.90 for EPI, difference between areas = 0.03, p = NS) and ejection fraction (EF) improvement (area under the curve of 0.87 for TDI vs. 0.93 for EPI, difference between areas = 0.06, p = NS). Furthermore, patients classified as responders by EPI (mean EPI-Index

Left ventricular hypertrophy as protective factor after bypass grafting.

PubMed

Iannuzzi, Gian Luca; Maniscalco, Mauro; Elia, Andrea; Scognamiglio, Anna; Furgi, Giuseppe; Rengo, Franco

2018-05-01

Left ventricular hypertrophy (LVH) is a well established cardiovascular risk factor, accounting for an increase in cardiovascular morbid-mortality, although how much the magnitude and the kind of LVH could affect cardiovascular outcomes is in large part unknown. We speculate that mild LVH in absence of left ventricular (LV) chamber dilation, could play a protective role towards functional capacity, clinical outcome, cardiovascular and total morbi-mortality in conditions in which LV systolic function is generally reduced. Accordingly to many epidemiological observations, the availability of extra-quote of systolic function could lead to a significative improvement in the final outcome of some kinds of heart patients, as those undergoing bypass-grafting, where the stress for heart and cardiovascular system is always high. We suppose that the functional reserve available for patients with LVH could make the difference with respect to other patients undergoing myocardial revascularization. Similarly, the availability of a contractile reserve warranted by LVH could ensure a little gain in the outcome for patients after other major cardiovascular events (such as myocardial infarction or other heart surgery as surgical valve replacement). However, our hypothesis only involves mild LVH without LV chamber dilation, that is the initial stage of "non-dilated concentric" LVH and "non-dilated eccentric" LVH according to the new four-tiered classification of LVH based on relative wall thickness and LV dilation. Support for our hypothesis derives from the well-known protective role of systolic function that is a major factor in almost all cardiovascular diseases, where LV ejection fraction (LVEF) has shown to significantly improve quality of life, as well as morbidity and mortality. The knowledge that mild LVH in absence of LV chamber dilation is not as harmful in such conditions as believed at present could make avoidable some drugs prescription in some stages of the disease. Furthermore, it may allow a better evaluation of the risk profile of patients with LVH undergoing some cardiovascular major events like bypass grafting, myocardial infarction or surgical heart valve replacement. Copyright © 2018 Elsevier Ltd. All rights reserved.

Fetal tissue Doppler imaging in pregnancies complicated with preeclampsia with or without intrauterine growth restriction.

PubMed

Zhou, Qiongjie; Ren, Yunyun; Yan, Yingliu; Chu, Chen; Gui, Yonghao; Li, Xiaotian

2012-11-01

This study's aim was to evaluate the effect of preeclampsia and intrauterine growth restriction (IUGR) on fetal cardiac function, and the relationship of the latter with adverse pregnancy outcomes. We did a cross-sectional study of 132 women with uncomplicated singleton pregnancies, 34 with preeclampsia without IUGR, and 12 with preeclampsia and IUGR. Fetal cardiac structure and function were evaluated using fetal two-dimension ultrasound, pulsed wave Doppler and tissue Doppler imaging (TDI). Data were analyzed by t-tests, ANOVA, Chi-square tests, or Wilcoxon rank-sum test. Compared with the normal pregnancy group, mitral/tricuspid early systolic peak velocity of annulus/late diastolic peak velocity of annulus (Sa) and left ventricular (LV)/right ventricular (RV) early diastolic peak velocity at the annulus (Ea) in TDI decreased in preeclampsia with or without IUGR (P < 0.05). LV/RV Ea underwent a gestational decrease in preeclampsia with or without IUGR (P < 0.05). The changes in mitral/tricuspid Sa and LV Sa associated with preeclampsia were even more pronounced with preterm delivery at less than 34 gestational weeks and stillbirth (P < 0.05). Intrauterine growth restriction influences fetal cardiac function in the presence of preeclampsia, and TDI may be a sensitive and preferable method to detect such changes. Fetal LV/RV Ea is a potential marker for early fetal cardiac diastolic impairment, and mitral/tricuspid Sa and LV Sa may be predictors for adverse pregnancy outcomes. © 2012 John Wiley & Sons, Ltd.

Novel mechanisms for caspase inhibition protecting cardiac function with chronic pressure overload

PubMed Central

Vatner, Stephen F.; Yan, Lin; Gao, Shumin; Yoon, Seunghun; Lee, Grace Jung Ah; Xie, Lai-Hua; Kitsis, Richard N.; Vatner, Dorothy E.

2013-01-01

Myocyte apoptosis is considered a major mechanism in the pathogenesis of heart failure. Accordingly, manipulations that inhibit apoptosis are assumed to preserve cardiac function by maintaining myocyte numbers. We tested this assumption by examining the effects of caspase inhibition (CI) on cardiac structure and function in C57BL/6 mouse with pressure overload model induced by transverse aortic constriction (TAC). CI preserved left ventricular (LV) function following TAC compared with the vehicle. TAC increased apoptosis in non-myocytes more than in myocytes and these increases were blunted more in non-myocytes by CI. Total myocyte number, however, did not differ significantly among control and TAC groups and there was no correlation between myocyte number and apoptosis, but there was a strong correlation between myocyte number and an index of myocyte proliferation, Ki67-positive myocytes. Despite comparable pressure gradients, LV hypertrophy was less in the CI group, likely attributable to decreased wall stress. Since changes in myocyte numbers did not account for protection from TAC, several other CI-mediated mechanisms were identified including: (a) lessening of TAC-induced fibrosis, (b) augmentation of isolated myocyte contractility, and (c) increased angiogenesis and Ki67-positive myocytes, which were due almost entirely to the non-myocyte apoptosis, but not myocyte apoptosis, with CI. CI maintained LV function following TAC not by protecting against myocyte loss, but rather by augmenting myocyte contractile function, myocyte proliferation, and angiogenesis resulting in reduced LV wall stress, hypertrophy, and fibrosis. PMID:23277091

Automated segmentation and reconstruction of patient-specific cardiac anatomy and pathology from in vivo MRI*

NASA Astrophysics Data System (ADS)

Ringenberg, Jordan; Deo, Makarand; Devabhaktuni, Vijay; Filgueiras-Rama, David; Pizarro, Gonzalo; Ibañez, Borja; Berenfeld, Omer; Boyers, Pamela; Gold, Jeffrey

2012-12-01

This paper presents an automated method to segment left ventricle (LV) tissues from functional and delayed-enhancement (DE) cardiac magnetic resonance imaging (MRI) scans using a sequential multi-step approach. First, a region of interest (ROI) is computed to create a subvolume around the LV using morphological operations and image arithmetic. From the subvolume, the myocardial contours are automatically delineated using difference of Gaussians (DoG) filters and GSV snakes. These contours are used as a mask to identify pathological tissues, such as fibrosis or scar, within the DE-MRI. The presented automated technique is able to accurately delineate the myocardium and identify the pathological tissue in patient sets. The results were validated by two expert cardiologists, and in one set the automated results are quantitatively and qualitatively compared with expert manual delineation. Furthermore, the method is patient-specific, performed on an entire patient MRI series. Thus, in addition to providing a quick analysis of individual MRI scans, the fully automated segmentation method is used for effectively tagging regions in order to reconstruct computerized patient-specific 3D cardiac models. These models can then be used in electrophysiological studies and surgical strategy planning.

Effects of exercise training on brain-derived neurotrophic factor in skeletal muscle and heart of rats post myocardial infarction.

PubMed

Lee, Heow Won; Ahmad, Monir; Wang, Hong-Wei; Leenen, Frans H H

2017-03-01

What is the central question of this study? Exercise training increases brain-derived neurotrophic factor (BDNF) in the hippocampus, which depends on a myokine, fibronectin type III domain-containing protein 5 (FNDC5). Whether exercise training after myocardial infarction induces parallel increases in FNDC5 and BDNF expression in skeletal muscle and the heart has not yet been studied. What is the main finding and its importance? Exercise training after myocardial infarction increases BDNF protein in skeletal muscle and the non-infarct area of the LV without changes in FNDC5 protein, suggesting that BDNF is not regulated by FNDC5 in skeletal muscle and heart. An increase in cardiac BDNF may contribute to the improvement of cardiac function by exercise training. Exercise training after myocardial infarction (MI) attenuates progressive left ventricular (LV) remodelling and dysfunction, but the peripheral stimuli induced by exercise that trigger these beneficial effects are still unclear. We investigated as possible mediators fibronectin type III domain-containing protein 5 (FNDC5) and brain-derived neurotrophic factor (BDNF) in the skeletal muscle and heart. Male Wistar rats underwent either sham surgery or ligation of the left descending coronary artery, and surviving MI rats were allocated to either a sedentary (Sed-MI) or an exercise group (ExT-MI). Exercise training was done for 4 weeks on a motor-driven treadmill. At the end, LV function was evaluated, and FNDC5 and BDNF mRNA and protein were assessed in soleus muscle, quadriceps and non-, peri- and infarct areas of the LV. At 5 weeks post MI, FNDC5 mRNA was decreased in soleus muscle and all areas of the LV, but FNDC5 protein was increased in the soleus muscle and the infarct area. Mature BDNF (mBDNF) protein was decreased in the infarct area without a change in mRNA. Exercise training attenuated the decrease in ejection fraction and the increase in LV end-diastolic pressure post MI. Exercise training had no effect on FNDC5 mRNA and protein, but increased mBDNF protein in soleus muscle, quadriceps and the non-infarct area of the LV. The mBDNF protein in the non-infarct area correlated positively with ejection fraction and inversely with LV end-diastolic pressure. In conclusion, mBDNF is induced by exercise training in skeletal muscle and the non-infarct area of the LV, which may contribute to improvement of muscle dysfunction and cardiac function post MI. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

Left ventricular torsion assessed by two-dimensional echocardiography speckle tracking as a predictor of left ventricular remodeling and short-term outcome following primary percutaneous coronary intervention for acute myocardial infarction: A single-center experience.

PubMed

Awadalla, Hany; Saleh, Mohamed Ayman; Abdel Kader, Mohamed; Mansour, Amr

2017-08-01

Left ventricular (LV) torsion is a novel method to assess systolic LV function. This study aimed at exploring the utility of 2D speckle tracking-based assessment of left ventricular torsion in patients with acute myocardial infarction (AMI) undertaking primary percutaneous intervention (pPCI) in predicting left ventricular remodeling. The study included 115 patients (mean±SD, age 52.2±9.67, males 84.3%) who underwent pPCI for AMI. Echocardiographic assessment of LV torsion by two-dimensional speckle tracking was performed early after the index pPCI. Patients underwent repeat echocardiography at 6 months to detect remodeling. LV torsion in the acute setting was significantly lower in those who demonstrated LV remodeling at follow-up compared to those without remodeling (7.56±1.95 vs 15.16±4.65; P<.005). Multivariate analysis identified peak CK & CK-MB elevation (β=-0.767 and -0.725; P<.001), SWMA index (β=-0.843; P<.001), and Simpson's derived LV ejection fraction (LVEF; β=0.802; P<.001) as independent predictors of baseline LV torsion. It also identified peak LV torsion (β: 0.27; 95% CI: 0.15-0.5, P=.001) and SWMA index (β: 1.07, 95% CI: 1.03-1.12, P=.005) as independent predictors of LV remodeling. Baseline Killip's grades II and higher (β: 48.6; 95% CI 5.5-428, P<.001) and diabetes mellitus (β: 29.7; 95% CI 1.1-763, P<.05) were independent predictors of mortality. Left ventricular torsion in acute MI setting is impaired and predicts subsequent LV remodeling at 6-month follow-up. © 2017, Wiley Periodicals, Inc.

Left Ventricular Reverse Remodeling With Biventricular Versus Right Ventricular Pacing in Patients With Atrioventricular Block and Heart Failure in the BLOCK HF Trial.

PubMed

St John Sutton, Martin; Plappert, Ted; Adamson, Philip B; Li, Pei; Christman, Shelly A; Chung, Eugene S; Curtis, Anne B

2015-05-01

Biventricular pacing in heart failure (HF) improves survival, relieves symptoms, and attenuates left ventricular (LV) remodeling. However, little is known about biventricular pacing in HF patients with atrioventricular block because they are typically excluded from biventricular trials. The Biventricular versus Right Ventricular Pacing in Heart Failure Patients with Atrioventricular Block (BLOCK HF) trial randomized patients with atrioventricular block, New York Heart Association symptom classes I to III HF, and LV ejection fraction ≤50% to biventricular or right ventricular pacing. Doppler echocardiograms were obtained at randomization (after 30 to 60 days of right ventricular pacing postimplant) and every 6 months through 24 months. Data analysis comparing changes in 10 prespecified echo parameters over time was conducted using a Bayesian design. LV end systolic volume index was also evaluated as a predictor of mortality/morbidity. Of 691 randomized subjects, 624 had paired Doppler echocardiogram data for ≥1 analyses at 6, 12, 18, or 24 months. Biventricular pacing significantly reduced LV volume indices and intraventricular mechanical delay, and improved LV ejection fraction, consistent with LV reverse remodeling. These parameters showed little change with right ventricular pacing alone, indicating no systematic reverse remodeling with right ventricular pacing. LV end systolic volume index was predictive of mortality/morbidity; the estimated risk increased up to 1% for every 1 mL/m(2) increase in LV end systolic volume index. LV end systolic volume index is a significant predictor of mortality/morbidity in this population. Cardiac structure and function are improved with biventricular pacing for patients with atrioventricular block and LV systolic dysfunction. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00267098. © 2015 American Heart Association, Inc.

Frequency-dependent left ventricular performance in women and men.

PubMed

Wainstein, Rodrigo V; Sasson, Zion; Mak, Susanna

2012-06-01

We aimed to determine whether sex differences in humans extend to the dynamic response of the left ventricular (LV) chamber to changes in heart rate (HR). Several observations suggest sex influences LV structure and function in health; moreover, this physiology is also affected in a sex-specific manner by aging. Eight postmenopausal women and eight similarly aged men underwent a cardiac catheterization-based study for force-interval relationships of the LV. HR was controlled by right atrial (RA) pacing, and LV +dP/dt(max) and volume were assessed by micromanometer-tipped catheter and Doppler echocardiography, respectively. Analysis of approximated LV pressure-volume relationships was performed using a time-varying model of elastance. External stroke work was also calculated. The relationship between HR and LV +dP/dt(max) was expressed as LV +dP/dt(max) = b + mHR. The slope (m) of the relationship was steeper in women compared with men (11.8 ± 4.0 vs. 6.1 ± 4.1 mmHg·s(-1)·beats(-1)·min(-1), P = 0.01). The greater increase in contractility in women was reproducibly observed after normalizing LV +dP/dt(max) to LV end-diastolic volume (LVVed) or by measuring end-systolic elastance. LVVed and stroke volume decreased more in women. Thus, despite greater increases in contractility, HR was associated with a lesser rise in cardiac output and a steeper fall in external stroke work in women. Compared with men, women exhibit greater inotropic responses to incremental RA pacing, which occurs at the same time as a steeper decline in external stroke work. In older adults, we observed sexual dimorphism in determinants of LV mechanical performance.

Specific gene delivery to liver sinusoidal and artery endothelial cells.

PubMed

Abel, Tobias; El Filali, Ebtisam; Waern, Johan; Schneider, Irene C; Yuan, Qinggong; Münch, Robert C; Hick, Meike; Warnecke, Gregor; Madrahimov, Nodir; Kontermann, Roland E; Schüttrumpf, Jörg; Müller, Ulrike C; Seppen, Jurgen; Ott, Michael; Buchholz, Christian J

2013-09-19

Different types of endothelial cells (EC) fulfill distinct tasks depending on their microenvironment. ECs are therefore difficult to genetically manipulate ex vivo for functional studies or gene therapy. We assessed lentiviral vectors (LVs) targeted to the EC surface marker CD105 for in vivo gene delivery. The mouse CD105-specific vector, mCD105-LV, transduced only CD105-positive cells in primary liver cell cultures. Upon systemic injection, strong reporter gene expression was detected in liver where mCD105-LV specifically transduced liver sinusoidal ECs (LSECs) but not Kupffer cells, which were mainly transduced by nontargeted LVs. Tumor ECs were specifically targeted upon intratumoral vector injection. Delivery of the erythropoietin gene with mCD105-LV resulted in substantially increased erythropoietin and hematocrit levels. The human CD105-specific vector (huCD105-LV) transduced exclusively human LSECs in mice transplanted with human liver ECs. Interestingly, when applied at higher dose and in absence of target cells in the liver, huCD105-LV transduced ECs of a human artery transplanted into the descending mouse aorta. The data demonstrate for the first time targeted gene delivery to specialized ECs upon systemic vector administration. This strategy offers novel options to better understand the physiological functions of ECs and to treat genetic diseases such as those affecting blood factors.

Interdependence of right ventricular systolic function and left ventricular filling and its association with outcome for patients with pulmonary hypertension.

PubMed

Motoji, Yoshiki; Tanaka, Hidekazu; Fukuda, Yuko; Sano, Hiroyuki; Ryo, Keiko; Imanishi, Junichi; Miyoshi, Tatsuya; Sawa, Takuma; Mochizuki, Yasuhide; Matsumoto, Kensuke; Emoto, Noriaki; Hirata, Ken-ichi

2015-04-01

Although impaired right ventricular (RV) performance has been associated with adverse outcomes for pulmonary hypertension (PH) patients, the relationship between bi-ventricular interdependence and outcomes is not yet fully understood. We studied 96 PH patients. RV systolic function was assessed by means of RV free-wall longitudinal speckle-tracking strain (RV-free), and left ventricular (LV) filling as early diastolic transmitral flow velocity (TMF-E). RV-free ≤19 % and TMF-E <60 cm/s were adopted as pre-defined cut-offs for RV systolic dysfunction and LV under-filling, respectively, associated with worse outcomes. Long-term outcome was tracked over 2.2 years. RV-free correlated significantly with TMF-E (r = 0.57, p < 0.001).TMF-E and RV-free were significantly lower in patients with than in those without cardiac events. RV systolic dysfunction and LV under-filling was observed in 35 patients. These features were associated with worse long-term survival compared to other sub-groups (log-rank p = 0.012). A sequential Cox model based on clinical variables including world health organization functional class IV and brain natriuretic peptide >150 pg/dl (χ(2) = 1.2) was improved by the addition of RV-free (χ(2) = 5.5, p = 0.04) as well as of TMF-E (χ(2) = 11.5, p = 0.01). In conclusions, RV systolic function was shown to correlate significantly with LV filling in PH patients. In addition, not only assessment of RV systolic function, but also of a combined bi-ventricular parameter comprising RV systolic function and LV filling may well have clinical implications for more successful management of PH patients.

Association of left ventricular longitudinal and circumferential systolic dysfunction with diastolic function in hypertension: a nonlinear analysis focused on the interplay with left ventricular geometry.

PubMed

Ballo, Piercarlo; Nistri, Stefano; Cameli, Matteo; Papesso, Barbara; Dini, Frank Lloyd; Galderisi, Maurizio; Zuppiroli, Alfredo; Mondillo, Sergio

2014-02-01

The relationships of left ventricular (LV) longitudinal and circumferential systolic dysfunction with diastolic performance in hypertensive patients have never been compared. In 532 asymptomatic hypertensive patients, circumferential function was assessed with the use of midwall fractional shortening (mFS) and stress-corrected mFS (SCmFS), whereas longitudinal function was assessed with the use of left atrioventricular plane displacement (AVPD) and systolic mitral annulus velocity (s'). Early diastolic annular velocity (e') and the E/e' ratio were measured. Global longitudinal and circumferential strain were determined in a subset of 210 patients. e' was linearly related to all systolic indexes (AVPD: R = 0.40; s': R = 0.39; mFS: R = 0.16; SCmFS: R = 0.17; all P < .0001), but the correlations were stronger with longitudinal indexes than with circumferential ones (P < .0001). E/e' was nonlinearly related to AVPD (R = -0.49; P < .0001) and s' (R = -0.34; P < .0001) and showed no relationship with mFS and SCmFS. Longitudinal indexes were superior to circumferential ones in predicting e' <8 cm/s, E/e' <8, and E/e' ≥13. The effect of LV geometry on LV diastolic function was evident among patients with preserved systolic longitudinal function, but was blunted among patients with impaired longitudinal function. In multivariable analyses, only longitudinal indexes remained associated with e' and E/e'. Analyses using strains provided similar results. In asymptomatic hypertensive subjects, LV diastolic performance is independently associated with longitudinal systolic dysfunction, but not with circumferential systolic dysfunction. Subtle longitudinal systolic impairment plays a role in mediating the effect of LV geometry on diastolic performance. These findings may support the need of critically revising the concept of isolated diastolic dysfunction in these patients. Copyright © 2014 Elsevier Inc. All rights reserved.

αConotoxin ArIB[V11L,V16D] is a potent and selective antagonist at rat and human native α7 nicotinic acetylcholine receptors

PubMed Central

Innocent, Neal; Livingstone, Phil D.; Hone, Arik; Kimura, Atsuko; Young, Tracey; Whiteaker, Paul; McIntosh, J. Michael; Wonnacott, Susan

2008-01-01

A recently developed α-conotoxin, α-CtxArIB[V11L,V16D] is a potent and selective competitive antagonist at rat recombinant α7 nicotinic acetylcholine receptors (nAChRs), making it an attractive probe for this receptor subtype. α7 nAChRs are potential therapeutic targets that are widely expressed in both neuronal and non-neuronal tissues where they are implicated in a variety of functions. Here we evaluate this toxin at rat and human native nAChRs. Functional α7 nAChR responses were evoked by choline plus the allosteric potentiator PNU-120596 in rat PC12 cells and human SHSY5Y cells loaded with calcium indicators. α-CtxArIB[V11L,V16D] specifically inhibited α7 nAChR-mediated increases in Ca2+ in PC12 cells. Responses to other stimuli (5-iodo-A-85380, nicotine or KCl) that did not activate α7 nAChRs were unaffected. Human α7 nAChRs were also sensitive to α-CtxArIB[V11L,V16D]: ACh-evoked currents in X. laevis oocytes expressing human α7 nAChRs were inhibited by α-CtxArIB[V11L,V16D] (IC50 3.4 nM) in a slowly reversible manner, with full recovery taking 15 min. This is consistent with the timecourse of recovery from blockade of rat α7 nAChRs in PC12 cells. α-CtxArIB[V11L,V16D] inhibited human native α7 nAChRs in SHSY5Y cells, activated by either choline or AR-R17779 plus PNU-120596. Rat brain α7 nAChRs contribute to dopamine release from striatal minces: α-CtxArIB[V11L,V16D] (300 nM) selectively inhibited choline-evoked dopamine release without affecting responses evoked by nicotine that activates heteromeric nAChRs. This study establishes that α-CtxArIB[V11L,V16D] selectively inhibits human and rat native α7 nAChRs with comparable potency, making this a potentially useful antagonist for investigating α7 nAChR functions. PMID:18664588

Cardiac structure and function in elite Native Hawaiian and Pacific Islander Rugby Football League athletes: an exploratory study.

PubMed

Johnson, Christopher; Forsythe, Lynsey; Somauroo, John; Papadakis, Michael; George, Keith; Oxborough, David

2018-05-01

The aim of this exploratory study was to define the Athletes Heart (AH) phenotype in Native Hawaiian & Pacific Islander (NH&PI) Rugby Football League (RFL) athletes. Specifically, (1) to describe conventional echocardiographic indices of left ventricle (LV) and right ventricle (RV) structure and function in NH&PI RFL players and matched RFL Caucasian controls (CC) and (2) to demonstrate LV and RV mechanics in these populations. Ethnicity is a contributory factor to the phenotypical expression of the AH. There are no data describing the cardiac phenotype in NH&PI athletes. Twenty-one male elite NH&PI RFL athletes were evaluated using conventional echocardiography and myocardial speckle tracking, allowing the assessment of global longitudinal strain (ε) and strain rate (SR); and basal, mid and global radial and circumferential ε and SR. Basal and apical rotation and twist were also assessed. Results were compared with age-matched Caucasian counterparts (CC; n = 21). LV mass [42 ± 9 versus 37 ± 4 g/(m 2.7 )], mean LV wall thickness (MWT: 9.5 ± 0.7 and 8.7 ± 0.4 mm), relative wall thickness (RWT: 0.35 ± 0.04 and 0.31 ± 0.03) and RV wall thickness (5 ± 1 and 4 ± 1 mm, all p < 0.05) were greater in NH&PI compared with CC. LV and RV cavity dimensions and standard indices of LV and RV systolic and diastolic function were similar between groups. NH&PI demonstrated reduced peak LV mid circumferential ε and early diastolic SR, as well as reduced global radial ε. There was reduced basal rotation at 25-35% systole, reduced apical rotation at 25-40% and 60-100% systole and reduced twist at 85-95% systole in NH&PI athletes. There were no differences between the two groups in RV wall mechanics. When compared to Caucasian controls, NH&PI rugby players have a greater LV mass, MWT and RWT with concomitant reductions in circumferential and twist mechanics. This data acts to prompt further research in NH&PI athletes.

Identifications of SUMO-1 cDNA and Its Expression Patterns in Pacific White Shrimp Litopeanaeus vannamei

PubMed Central

Laoong-u-thai, Yanisa; Zhao, Baoping; Phongdara, Amornrat; Ako, Harry; Yang, Jinzeng

2009-01-01

Small ubiquitin-like modifiers (SUMO) work in a similar way as ubiquitin to alter the biological properties of a target protein by conjugation. A shrimp SUMO cDNA named LvSUMO-1 was identified in Litopenaeus vannamei. LvSUMO-1 cDNA contains a coding sequence of 282 nucleotides with untranslated regions of 37 bp at 5'-end and 347 bp at 3'-end, respectively. The deduced 93 amino acids exhibit 83% identity with the Western Honeybee SUMO-1, and more than 65% homologies with human and mouse SUMO-1. LvSUMO-1 mRNA is expressed in most L. vannamei tissues with the highest level in hepatopancrease. The mRNA expression of LvSUMO-1 over development stages in L. Vammamei is distinguished by a low level in nauplius stage and relatively high level in postlarva stage with continuous expression until juvenile stage. The LvSUMO-1 protein and its conjugated proteins are detected in both cytoplasm and nucleus in several tissues. Interestingly, LvSUMO-1 mRNA levels are high in abdominal muscle during the premolt stage, wherein it has significant activities of protein degradation, suggesting its possible role in the regulation of shrimp muscle protein degradation. PMID:19240809

Latent cardiac dysfunction as assessed by echocardiography in bed-bound patients following cerebrovascular accidents: comparison with nutritional status.

PubMed

Masugata, Hisashi; Senda, Shoichi; Goda, Fuminori; Yoshihara, Yumiko; Yoshikawa, Kay; Fujita, Norihiro; Himoto, Takashi; Okuyama, Hiroyuki; Taoka, Teruhisa; Imai, Masanobu; Kohno, Masakazu

2007-07-01

The aim of this study was to elucidate the cardiac function in bed-bound patients following cerebrovascular accidents. In accord with the criteria for activities of daily living (ADL) of the Japanese Ministry of Health, Labour and Welfare, 51 age-matched poststroke patients without heart disease were classified into 3 groups: rank A (house-bound) (n = 16, age, 85 +/- 6 years), rank B (chair-bound) (n = 16, age, 84 +/- 8 years), and rank C (bed-bound) (n = 19, age, 85 +/- 9 years). Using echocardiography, the left ventricular (LV) diastolic function was assessed by the ratio of early filling (E) and atrial contraction (A) transmitral flow velocities (E/A) of LV inflow. LV systolic function was assessed by LV ejection fraction (LVEF), and the Tei index was also measured to assess both LV systolic and diastolic function. No difference was observed in the E/A and LVEF among the 3 groups. The Tei index was higher in rank C (0.56 +/- 0.17) than in rank A (0.39 +/- 0.06) and rank B (0.48 +/- 0.17), and a statistically significant difference was observed between rank A and rank C (P < 0.05). Serum albumin and blood hemoglobin were significantly lower in rank C (3.1 +/- 0.4 and 10.6 +/- 1.8 g/dL) than in rank A (4.1 +/- 0.3 and 12.4 +/- 1.2 g/dL) (P < 0.001 and P < 0.05, respectively). These results indicate that latent cardiac dysfunction and poor nutritional status may exist in bed-bound patients (rank C) following cerebrovascular accidents. The Tei index may be a useful index of cardiac dysfunction in bed-bound patients because it is independent of the cardiac loading condition.

Effects of milrinone on left ventricular cardiac function during cooling in an intact animal model.

PubMed

Tveita, Torkjel; Sieck, Gary C

2012-08-01

Due to adverse effects of β-receptor agonists reported when applied during hypothermia, left ventricular (LV) cardiac effects of milrinone, a PDE3 inhibitor which mode of action is deprived the sarcolemmal β-receptor-G protein-PKA system, was tested during cooling to 15 °C. Sprague Dawley rats were instrumented to measure left ventricular (LV) pressure-volume changes using a Millar pressure-volume conductance catheter. Core temperature was reduced from 37 to 15 °C (60 min) using internal and external heat exchangers. Milrinone, or saline placebo, was given as continuous i.v. infusions for 30 min at 37 °C and during cooling. In normothermic controls continuous milrinone infusion for 90 min elevated cardiac output (CO) and stroke volume (SV) significantly. Significant differences in cardiac functional variables between the milrinone group and the saline control group during cooling to 15 °C were found: Compared to saline treated animals throughout cooling from 33 to 15 °CSV was significantly elevated in milrinone animals, the index of LV isovolumic relaxation, Tau, was significantly better preserved, and both HR and CO were significantly higher from 33 to 24 °C. Likewise, during cooling between 33 and 28 °C also LVdP/dt(max) was significantly higher in the milrinone group. Milrinone preserved LV systolic and diastolic function at a significantly higher level than in saline controls during cooling to 15 °C. In essential contrast to our previous results when using β-receptor agonists during hypothermia, the present experiment demonstrates the positive inotropic effects of milrinone on LV cardiac function during cooling to 15 °C. Copyright © 2012 Elsevier Inc. All rights reserved.

Magnetic resonance-compatible model of isolated working heart from large animal for multimodal assessment of cardiac function, electrophysiology, and metabolism.

PubMed

Vaillant, Fanny; Magat, Julie; Bour, Pierre; Naulin, Jérôme; Benoist, David; Loyer, Virginie; Vieillot, Delphine; Labrousse, Louis; Ritter, Philippe; Bernus, Olivier; Dos Santos, Pierre; Quesson, Bruno

2016-05-15

To provide a model close to the human heart, and to study intrinsic cardiac function at the same time as electromechanical coupling, we developed a magnetic resonance (MR)-compatible setup of isolated working perfused pig hearts. Hearts from pigs (40 kg, n = 20) and sheep (n = 1) were blood perfused ex vivo in the working mode with and without loaded right ventricle (RV), for 80 min. Cardiac function was assessed by measuring left intraventricular pressure and left ventricular (LV) ejection fraction (LVEF), aortic and mitral valve dynamics, and native T1 mapping with MR imaging (1.5 Tesla). Potential myocardial alterations were assessed at the end of ex vivo perfusion from late-Gadolinium enhancement T1 mapping. The ex vivo cardiac function was stable across the 80 min of perfusion. Aortic flow and LV-dP/dtmin were significantly higher (P < 0.05) in hearts perfused with loaded RV, without differences for heart rate, maximal and minimal LV pressure, LV-dP/dtmax, LVEF, and kinetics of aortic and mitral valves. T1 mapping analysis showed a spatially homogeneous distribution over the LV. Simultaneous recording of hemodynamics, LVEF, and local cardiac electrophysiological signals were then successfully performed at baseline and during electrical pacing protocols without inducing alteration of MR images. Finally, (31)P nuclear MR spectroscopy (9.4 T) was also performed in two pig hearts, showing phosphocreatine-to-ATP ratio in accordance with data previously reported in vivo. We demonstrate the feasibility to perfuse isolated pig hearts in the working mode, inside an MR environment, allowing simultaneous assessment of cardiac structure, mechanics, and electrophysiology, illustrating examples of potential applications. Copyright © 2016 the American Physiological Society.

Distribution of late gadolinium enhancement in various types of cardiomyopathies: Significance in differential diagnosis, clinical features and prognosis

PubMed Central

Satoh, Hiroshi; Sano, Makoto; Suwa, Kenichiro; Saitoh, Takeji; Nobuhara, Mamoru; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Hayashi, Hideharu

2014-01-01

The recent development of cardiac magnetic resonance (CMR) techniques has allowed detailed analyses of cardiac function and tissue characterization with high spatial resolution. We review characteristic CMR features in ischemic and non-ischemic cardiomyopathies (ICM and NICM), especially in terms of the location and distribution of late gadolinium enhancement (LGE). CMR in ICM shows segmental wall motion abnormalities or wall thinning in a particular coronary arterial territory, and the subendocardial or transmural LGE. LGE in NICM generally does not correspond to any particular coronary artery distribution and is located mostly in the mid-wall to subepicardial layer. The analysis of LGE distribution is valuable to differentiate NICM with diffusely impaired systolic function, including dilated cardiomyopathy, end-stage hypertrophic cardiomyopathy (HCM), cardiac sarcoidosis, and myocarditis, and those with diffuse left ventricular (LV) hypertrophy including HCM, cardiac amyloidosis and Anderson-Fabry disease. A transient low signal intensity LGE in regions of severe LV dysfunction is a particular feature of stress cardiomyopathy. In arrhythmogenic right ventricular cardiomyopathy/dysplasia, an enhancement of right ventricular (RV) wall with functional and morphological changes of RV becomes apparent. Finally, the analyses of LGE distribution have potentials to predict cardiac outcomes and response to treatments. PMID:25068019

Pulmonary Hyperinflation and Left Ventricular Mass

PubMed Central

Smith, Benjamin M; Kawut, Steven M.; Bluemke, David A; Basner, Robert C; Gomes, Antoinette S; Hoffman, Eric; Kalhan, Ravi; Lima, João AC; Liu, Chia-Ying; Michos, Erin D; Prince, Martin R; Rabbani, LeRoy; Rabinowitz, Daniel; Shimbo, Daichi; Shea, Steven; Barr, R Graham

2013-01-01

Background Left ventricular (LV) mass is an important predictor of heart failure and cardiovascular mortality, yet determinants of LV mass are incompletely understood. Pulmonary hyperinflation in chronic obstructive pulmonary disease (COPD) may contribute to changes in intrathoracic pressure that increase LV wall stress. We therefore hypothesized that residual lung volume in COPD would be associated with greater LV mass. Methods and results The Multi-Ethnic Study of Atherosclerosis (MESA) COPD Study recruited smokers aged 50–79 years who were free of clinical cardiovascular disease. LV mass was measured by cardiac magnetic resonance. Pulmonary function testing was performed according to guidelines. Regression models were used to adjust for age, sex, body size, blood pressure and other cardiac risk factors. Among 119 MESA COPD Study participants, mean age was 69±6 years, 55% were male and 65% had COPD, mostly of mild or moderate severity. Mean LV mass was 128±34 grams. Residual lung volume was independently associated with greater LV mass (7.2 grams per standard deviation increase in residual volume; 95% CI 2.2 to 12; P=0.004), and was similar in magnitude to that of systolic blood pressure (7.6 grams per standard deviation increase in systolic blood pressure, 95% CI 4.3 to 11 grams; p<0.001). Similar results were observed for LV mass to end-diastolic volume ratio (p=0.02) and with hyperinflation measured as residual volume to total lung capacity ratio (P=0.009). Conclusions Pulmonary hyperinflation, as measured by residual lung volume or residual lung volume to total lung capacity ratio, is associated with greater LV mass. PMID:23493320

Heart Disease and Left Ventricular Rotation – A Systematic Review and Quantitative Summary

PubMed Central

2012-01-01

Background Left ventricular (LV) rotation is increasingly examined in those with heart disease. The available evidence measuring LV rotation in those with heart diseases has not been systematically reviewed. Methods To review systematically the evidence measuring LV rotational changes in various heart diseases compared to healthy controls, literature searches were conducted for appropriate articles using several electronic databases (e.g., MEDLINE, EMBASE). All randomized-controlled trials, prospective cohort and case–controlled studies that assessed LV rotation in relation to various heart conditions were included. Three independent reviewers evaluated each investigation’s quality using validated scales. Results were tabulated and levels of evidence assigned. Results A total of 1,782 studies were found through the systematic literature search. Upon review of the articles, 47 were included. The articles were separated into those investigating changes in LV rotation in participants with: aortic stenosis, myocardial infarction, hypertrophic cardiomyopathy, dilated cardiomyopathy, non-compaction, restrictive cardiomyopathy/ constrictive pericarditis, heart failure, diastolic dysfunction, heart transplant, implanted pacemaker, coronary artery disease and cardiovascular disease risk factors. Evidence showing changes in LV rotation due to various types of heart disease was supported by evidence with limited to moderate methodological quality. Conclusions Despite a relatively low quality and volume of evidence, the literature consistently shows that heart disease leads to marked changes in LV rotation, while rotational systolic-diastolic coupling is preserved. No prognostic information exists on the potential value of rotational measures of LV function. The literature suggests that measures of LV rotation may aid in diagnosing subclinical aortic stenosis and diastolic dysfunction. PMID:22726250

Actin genes and their expression in pacific white shrimp, Litopenaeus vannamei.

PubMed

Zhang, Xiaoxi; Zhang, Xiaojun; Yuan, Jianbo; Du, Jiangli; Li, Fuhua; Xiang, Jianhai

2018-04-01

Actin is a multi-functional gene family that can be divided into muscle-type actins and non-muscle-type actins. In this study, 37 unigenes encoding actins were identified from RNA-Seq data of Pacific white shrimp, Litopenaeus vannamei. According to phylogenetic analysis, four and three cDNAs belong to cytoplasmic- and heart-type actins and were named LvActinCT and LvActinHT, respectively. 10 cDNAs belong to the slow-type skeletal muscle actins, and 18 belong to the fast-type skeletal muscle actins; they were designated LvActinSSK and LvActinFSK, respectively. Some muscle actin genes formed gene clusters in the genome. Multiple alternative transcription starts sites (ATSSs) were found for LvActinCT1. Based on the early developmental expression profile, almost all LvActins were highly expressed between the early limb bud and post-larval stages. Using LvActinSSK5 as probes, slow-type muscle was localized in pleopod muscle and superficial ventral muscle. We also found three actin genes that were down-regulated in the hemocytes of white spot syndrome virus (WSSV)- and Vibrio parahaemolyticus-infected L. vannamei. This study provides valuable information on the actin gene structure of shrimp, furthers our understanding of the shrimp muscle system and helps us develop strategies for disease control and sustainable shrimp farming.

Echocardiographic Manifestations of Glycogen Storage Disease III: Increase in Wall Thickness and Left Ventricular Mass over Time

PubMed Central

Vertilus, Shawyntee M.; Austin, Stephanie L.; Foster, Kimberly S.; Boyette, Keri E.; Bali, Deeksha; Li, Jennifer S.; Kishnani, Priya S.; Wechsler, Stephanie Burns

2013-01-01

Purpose Glycogen Storage Disease (GSD) type III, glycogen debranching enzyme deficiency, causes accumulation of glycogen in liver, skeletal, and cardiac muscle. Some patients develop increased left ventricular (LV) thickness by echocardiography, but the rate of increase and its significance remain unclear. Methods We evaluated 33 patients with GSD type III, 23 with IIIa and 10 with IIIb, ages 1 month – 55.5 yrs, by echocardiography for wall thickness, LV mass, shortening and ejection fractions, at 1 time point (n = 33) and at 2 time points in patients with more than 1 echocardiogram (13 of the 33). Results Of 23 cross-sectional patients with type IIIa, 12 had elevated LV mass, 11 had elevated wall thickness. One type IIIb patient had elevated LV mass but 4 had elevated wall thickness. For those with multiple observations, 9 of 10 with type IIIa developed increased LV mass over time, with 3 already increased at first measurement. Shortening and ejection fractions were generally normal. Conclusion Elevated LV mass and wall thickness is more common in patients with type IIIa but develops rarely in type IIIb, though ventricular systolic function is preserved. This suggests serial echocardiograms with attention to LV thickness and mass are important for care of these patients. PMID:20526204

Molecular Mechanisms of Right Ventricular Failure

PubMed Central

Reddy, Sushma; Bernstein, Daniel

2015-01-01

An abundance of data has provided insight into the mechanisms underlying the development of left ventricular (LV) hypertrophy and its progression to LV failure. In contrast, there is minimal data on the adaptation of the right ventricle (RV) to pressure and volume overload and the transition to RV failure. This is a critical clinical question, as the RV is uniquely at risk in many patients with repaired or palliated congenital heart disease and in those with pulmonary hypertension. Standard heart failure therapies have failed to improve function or survival in these patients, suggesting a divergence in the molecular mechanisms of RV vs. LV failure. Although, on the cellular level, the remodeling responses of the RV and LV to pressure overload are largely similar, there are several key differences: the stressed RV is more susceptible to oxidative stress, has a reduced angiogenic response, and is more likely to activate cell death pathways than the stressed LV. Together, these differences could explain the more rapid progression of the RV to failure vs. the LV. This review will highlight known molecular differences between the RV and LV responses to hemodynamic stress, the unique stressors on the RV associated with congenital heart disease, and the need to better understand these molecular mechanisms if we are to develop RV-specific heart failure therapeutics. PMID:26527692

Association of isolated minor nonspecific ST-T abnormalities with left ventricular hypertrophy and diastolic dysfunction.

PubMed

Kang, Jeong Gyu; Chang, Yoosoo; Sung, Ki-Chul; Kim, Jang-Young; Shin, Hocheol; Ryu, Seungho

2018-06-08

The aim of this study was to examine the associations of isolated minor nonspecific ST-T abnormalities (NSSTTA) on 12-lead electrocardiogram (ECG) with left ventricular (LV) diastolic function and LV geometry on echocardiography. A cross-sectional study comprised of 74,976 Koreans who underwent ECG and echocardiography as part of a comprehensive health examination between March 2011 and December 2014. ECG was coded using Minnesota Code criteria. The frequencies of NSSTTA, impaired LV relaxation, and echocardiographic LVH were 1,139 (1.5%), 21,118 (28.2%), and 1,687 (2.3%) patients, respectively. The presence of NSSTTA was positively associated with the prevalence of impaired LV relaxation and LVH on echocardiography. In a multivariable-adjusted model, the odds ratio (95% CIs) comparing patients with NSSTTA to control patients was 1.55 (1.33-1.80) for impaired LV relaxation and 3.15 (2.51-3.96) for echocardiographic LVH. The association between NSSTTA and impaired LV relaxation was stronger in the intermediate to high cardiovascular disease-risk group than in the low-risk group according to Framingham Risk Score stratification (P for interaction = 0.02). NSSTTA were associated with increased prevalence of impaired LV relaxation and LVH, suggesting NSSTTA as an early indicator of subclinical cardiac dysfunction and geometric abnormalities.

Inputs from regularly and irregularly discharging vestibular nerve afferents to secondary neurons in squirrel monkey vestibular nuclei. III. Correlation with vestibulospinal and vestibuloocular output pathways

NASA Technical Reports Server (NTRS)

Boyle, R.; Goldberg, J. M.; Highstein, S. M.

1992-01-01

1. A previous study measured the relative contributions made by regularly and irregularly discharging afferents to the monosynaptic vestibular nerve (Vi) input of individual secondary neurons located in and around the superior vestibular nucleus of barbiturate-anesthetized squirrel monkeys. Here, the analysis is extended to more caudal regions of the vestibular nuclei, which are a major source of both vestibuloocular and vestibulospinal pathways. As in the previous study, antidromic stimulation techniques are used to classify secondary neurons as oculomotor or spinal projecting. In addition, spinal-projecting neurons are distinguished by their descending pathways, their termination levels in the spinal cord, and their collateral projections to the IIIrd nucleus. 2. Monosynaptic excitatory postsynaptic potentials (EPSPs) were recorded intracellularly from secondary neurons as shocks of increasing strength were applied to Vi. Shocks were normalized in terms of the threshold (T) required to evoke field potentials in the vestibular nuclei. As shown previously, the relative contribution of irregular afferents to the total monosynaptic Vi input of each secondary neuron can be expressed as a %I index, the ratio (x100) of the relative sizes of the EPSPs evoked by shocks of 4 x T and 16 x T. 3. Antidromic stimulation was used to type secondary neurons as 1) medial vestibulospinal tract (MVST) cells projecting to spinal segments C1 or C6; 2) lateral vestibulospinal tract (LVST) cells projecting to C1, C6; or L1; 3) vestibulooculo-collic (VOC) cells projecting both to the IIIrd nucleus and by way of the MVST to C1 or C6; and 4) vestibuloocular (VOR) neurons projecting to the IIIrd nucleus but not to the spinal cord. Most of the neurons were located in the lateral vestibular nucleus (LV), including its dorsal (dLV) and ventral (vLV) divisions, and adjacent parts of the medial (MV) and descending nuclei (DV). Cells receiving quite different proportions of their direct inputs from regular and irregular afferents were intermingled in all regions explored. 4. LVST neurons are restricted to LV and DV and show a somatotopic organization. Those destined for the cervical and thoracic cord come from vLV, from a transition zone between vLV and DV, and to a lesser extent from dLV. Lumbar-projecting neurons are located more dorsally in dLV and more caudally in DV. MVST neurons reside in MV and in the vLV-DV transition zone.(ABSTRACT TRUNCATED AT 400 WORDS).

A single WAP domain (SWD)-containing protein with antiviral activity from Pacific white shrimp Litopenaeus vannamei.

PubMed

Yang, Linwei; Niu, Shengwen; Gao, Jiefeng; Zuo, Hongliang; Yuan, Jia; Weng, Shaoping; He, Jianguo; Xu, Xiaopeng

2018-02-01

The single whey acidic protein (WAP) domain (SWD)-containing proteins, also called type III crustins, are a group of antimicrobial peptides (AMPs) in crustaceans. At present, a number of SWDs have been identified in shrimp, which showed essential antibacterial activities. However, the roles of SWDs in antiviral immune responses have not been reported up to now. In this study, a novel SWD (LvSWD3) was identified from Pacific white shrimp, Litopenaeus vannamei, which contained a typical single WAP domain homologous to those of other crustacean SWDs. Although lacking the pro and arg-rich region between the signal peptide and the WAP domain, LvSWD3 was closely clustered with other shrimp SWDs in the phylogenetic tree. Similar to many shrimp SWDs, the highest expression of LvSWD3 was detected in hemocytes. The LvSWD3 expression exhibited only limited changes after challenges with Vibrio parahaemolyticus, Poly (I:C) and lipopolysaccharide, but was significantly up-regulated after white spot syndrome virus (WSSV) infection. Silencing of LvSWDs significantly accelerated the death of the WSSV-infected but not the V. parahaemolyticus-infected shrimp. The recombinant LvSWD3 protein did not show proteinase inhibitory and antibacterial activities but could significantly postpone the death of WSSV-infected shrimp and reduce the viral load in tissues. These suggested that LvSWD3 was a novel SWD with antiviral activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Early beneficial effect of preservation of papillo-annular continuity in mitral valve replacement on left ventricular function.

PubMed

Dilip, D; Chandra, A; Rajashekhar, D; Padmanabhan, M

2001-05-01

Impairment of left ventricular (LV) function after mitral valve replacement (MVR) has been the most important factor to determine morbidity and mortality. With this in mind, LV performance in the postoperative period was assessed with and without preservation of papillo-annular continuity in MVR. Between March 1994 and August 1998, a total of 383 valve prostheses (202 MVR, 65 AVR, 58 MVR+AVR) were implanted in 325 patients, 177 of whom underwent MVR with Starr Edwards ball cage prostheses (the study group). Of these 177 patients, 105 had MVR with preservation of the posterior mitral leaflet (group I), and 72 had conventional MVR (group II). Predominant lesions were mitral stenosis in 81, mitral regurgitation in 42, and mixed mitral lesion (MS/MR) in 54. Concomitant tricuspid valve annuloplasty was performed in 13, and atrial septal defect repair in five. Sixteen patients underwent MVR for mitral restenosis. In-vivo performance of the prostheses and LV function was evaluated by M-mode and Doppler echocardiography. At 3-6 months clinical improvement was seen in NYHA class, with reduction in cardiothoracic ratio among patients with preserved papillo-annular continuity, irrespective of lesion type. Significant reductions (p <0.05) were seen in left atrial dimensions (54.10 +/- 8.79 preop. versus 44.64 +/- 8.54 postop.; p <0.05), left ventricular end-diastolic dimensions (LVEDD) (50.84 +/- 10.42 preop. versus 41.21 +/- 7.16 postop.; p <0.05) and end-systolic dimensions (LVESD) (34.76 +/- 7.94 preop. versus 28.81 +/- 5.79 postop.; p <0.05) in patients who had their posterior mitral leaflet preserved with significant improvement in ejection fraction (60.31 +/- 8.22 versus 64.47 +/- 7.93; p <0.05). Further analysis of data in group I patients showed significant reductions in left atrial dimensions, LVESD and peak gradient, along with improved ejection fraction compared with conventional (group II) patients. Deterioration in LV function in patients undergoing conventional MVR indicates chordal resection as a putative mechanism. This study supports the concept that maintenance of continuity between the mitral annulus and papillary muscles has a beneficial effect on postoperative LV function, and is particularly important in patients with mitral stenosis with depressed preoperative LV systolic function.

Free-breathing Sparse Sampling Cine MR Imaging with Iterative Reconstruction for the Assessment of Left Ventricular Function and Mass at 3.0 T.

PubMed

Sudarski, Sonja; Henzler, Thomas; Haubenreisser, Holger; Dösch, Christina; Zenge, Michael O; Schmidt, Michaela; Nadar, Mariappan S; Borggrefe, Martin; Schoenberg, Stefan O; Papavassiliu, Theano

2017-01-01

Purpose To prospectively evaluate the accuracy of left ventricle (LV) analysis with a two-dimensional real-time cine true fast imaging with steady-state precession (trueFISP) magnetic resonance (MR) imaging sequence featuring sparse data sampling with iterative reconstruction (SSIR) performed with and without breath-hold (BH) commands at 3.0 T. Materials and Methods Ten control subjects (mean age, 35 years; range, 25-56 years) and 60 patients scheduled to undergo a routine cardiac examination that included LV analysis (mean age, 58 years; range, 20-86 years) underwent a fully sampled segmented multiple BH cine sequence (standard of reference) and a prototype undersampled SSIR sequence performed during a single BH and during free breathing (non-BH imaging). Quantitative analysis of LV function and mass was performed. Linear regression, Bland-Altman analysis, and paired t testing were performed. Results Similar to the results in control subjects, analysis of the 60 patients showed excellent correlation with the standard of reference for single-BH SSIR (r = 0.93-0.99) and non-BH SSIR (r = 0.92-0.98) for LV ejection fraction (EF), volume, and mass (P < .0001 for all). Irrespective of breath holding, LV end-diastolic mass was overestimated with SSIR (standard of reference: 163.9 g ± 58.9, single-BH SSIR: 178.5 g ± 62.0 [P < .0001], non-BH SSIR: 175.3 g ± 63.7 [P < .0001]); the other parameters were not significantly different (EF: 49.3% ± 11.9 with standard of reference, 48.8% ± 11.8 with single-BH SSIR, 48.8% ± 11 with non-BH SSIR; P = .03 and P = .12, respectively). Bland-Altman analysis showed similar measurement errors for single-BH SSIR and non-BH SSIR when compared with standard of reference measurements for EF, volume, and mass. Conclusion Assessment of LV function with SSIR at 3.0 T is noninferior to the standard of reference irrespective of BH commands. LV mass, however, is overestimated with SSIR. © RSNA, 2016 Online supplemental material is available for this article.

Left ventricular wall stress and sarcoplasmic reticulum Ca(2+)-ATPase gene expression in renal hypertensive rats: dose-dependent effects of ACE inhibition and AT1-receptor blockade.

PubMed

Zierhut, W; Studer, R; Laurent, D; Kästner, S; Allegrini, P; Whitebread, S; Cumin, F; Baum, H P; de Gasparo, M; Drexler, H

1996-05-01

Cardiac hypertrophy is associated with altered Ca2+ handling and may predispose to the development of LV dysfunction and cardiac failure. At the cellular level, the re-expression of ANF represents a well-established marker of myocyte hypertrophy while the decreased expression of the sarcoplasmatic reticulum (SR) Ca(2+)-ATPase is thought o play a crucial role in the alterations of Ca2+ handling and LV function. We assessed the dose-dependent effect of chronic ACE inhibition or AT1 receptor blockade on cardiac function in relation to the cardiac expression of the SR Ca(2+)-ATPase and ANF. Renal hypertensive rats (2K-1C) were treated for 12 weeks with three different doses of the ACE inhibitor benazepril, the AT1-receptor antagonist valsartan (each drug 0.3, 3, and 10 mg/kg per day i.p.) or placebo. LV dimensions, hypertrophy and wall stress were determined in vivo by magnetic resonance imaging and the gene expressions of ANF and SR Ca(2+)-ATPase were quantified by Northern blot. Low doses of both drugs did not affect blood pressure, hypertrophy, systolic wall stress and the ANF and SR Ca(2+)-ATPase gene expression. High doses of each drug reduced systolic blood pressure, wall stress, and LV hypertrophy to a similar extent and to values comparable to normotensive, age-matched rats. In addition, high dose treatment reduced LV end-systolic and end-diastolic volume as compared to untreated 2K-1C animals and normalized the mRNA levels of both ANF and SR Ca(2+)-ATPase (as compared to normotensive animals). We conclude that in this model, high doses of ACE inhibition and AT1-receptor blockade are necessary to normalize systolic blood pressure, LV hypertrophy and systolic LV wall stress which, in turn, is associated with restoration of a normal cardiac phenotype with respect to SR Ca(2+)-ATPase and ANF and normalization of cardiac function.

Influence of automatic frequent pace-timing adjustments on effective left ventricular pacing during cardiac resynchronization therapy.

PubMed

Varma, Niraj; Stadler, Robert W; Ghosh, Subham; Kloppe, Axel

2017-05-01

Cardiac resynchronization therapy (CRT) requires effective left ventricular (LV) pacing (i.e. sufficient energy and appropriate timing to capture). The AdaptivCRT™ (aCRT) algorithm serves to maintain ventricular fusion during LV or biventricular pacing. This function was tested by comparing the morphological consistency of ventricular depolarizations and percentage effective LV pacing in CRT patients randomized to aCRT vs. echo-optimization. Continuous recordings (≥20 h) of unipolar LV electrograms from aCRT (n = 38) and echo-optimized patients (n = 22) were analysed. Morphological consistency was determined by the correlation coefficient between each beat and a template beat. Effective LV pacing of paced beats was assessed by algorithmic analysis of negative initial EGM deflection in each evoked response. The %CRT pacing delivered, %effective LV pacing (i.e. % of paced beats with effective LV pacing), and overall %effective CRT (i.e. product of %CRT pacing and %effective LV pacing) were compared between aCRT and echo-optimized patients. Demographics were similar between groups. The mean correlation coefficient between individual beats and template was greater for aCRT (0.96 ± 0.03 vs. 0.91 ± 0.13, P = 0.07). Although %CRT pacing was similar for aCRT and echo-optimized (median 97.4 vs. 98.6%, P = 0.14), %effective LV pacing was larger for aCRT [99.6%, (99.1%, 99.9%) vs. 94.3%, (24.3%, 99.8%), P=0.03]. For aCRT vs. echo-optimized groups, the proportions of patients with ≥90% effective LV pacing was 92 vs. 55% (P = 0.002), and with ≥90% effective CRT was 79 vs. 45%, respectively (P = 0.018). AdaptivCRT™ significantly increased effective LV pacing over echo-optimized CRT. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Enhanced functional stability of plasminogen activator inhibitor-1 in patients with livedoid vasculopathy.

PubMed

Agirbasli, Mehmet; Eren, Mesut; Eren, Fatih; Murphy, Sheila B; Serdar, Zehra A; Seckin, Dilek; Zara, Tuba; Cem Mat, M; Demirkesen, Cuyan; Vaughan, Douglas E

2011-07-01

Livedoid vasculopathy (LV) is a chronic, recurrent, painful cutaneous disease with distinctive clinical features and an uncertain etiology. The skin lesions are recognizable by focal purpura, depigmentation and shallow ulcers. Thrombophilic conditions occur frequently in patients with LV. While no definitive treatment exists for LV, smoking cessation, antiplatelet therapy, immunosuppressive treatment, and anabolic steroids are often included in the therapeutic ladder. Recently, a possible link between LV and impaired fibrinolysis was established as cutaneous LV lesions responded to tissue plasminogen activator (t-PA) infusion suggesting that inhibition of the fibrinolysis through plasminogen activator inhibitor-1 (PAI-1) activity may determine the disease course in patients with LV. In this study, we investigated PAI-1 antigen (Ag) and activity levels in 20 patients with biopsy proven LV (mean age 26 ± 11, M/F = 7/13, median disease duration 3.5 years). All patients received antiplatelet treatment with aspirin and/or dipyrimadole and 14 patients received anabolic steroids or immunosuppressive treatment. Fasting PAI-1 Ag and activity levels were measured at 9 AM in all patients. Both Ag (34 (26) ng/ml) (median (interquartile range)) and specific activity (17 (23) IU/fmole) levels of PAI-1 were moderately elevated in LV patients compared to the controls, however, PAI-1 kinetic studies demonstrated markedly enhanced stability of PAI-1 activity in plasma from patients with LV. Specific activity at 16 h was significantly higher than expected specific activity levels (7 (11) vs. 0.07 (0.09) IU/fmole, P < 0.01). While the exact mechanism of increased stability of PAI-1 activity is not known, it may be due to post-translational modifications or increased binding affinity for a stabilizing cofactor. In conclusion, enhanced stability of PAI-1 may contribute to the pathophysiology of LV, and systemic or local treatment with PAI-1 inhibitors may offer a potential treatment alternative in patients with LV.

Cardiac considerations in the triathlete.

PubMed

Douglas, P S

1989-10-01

The cardiac adaptation to exercise training produces a variety of adaptations in cardiac size, shape, and function. To further define these changes and to investigate the effects of maximal conditioning, we studied ultraendurance triathletes training for the Hawaii Ironman Triathlon using echocardiography, Doppler ultrasound, and electrocardiography. In this population, the left ventricle (LV) was of normal size but had increased wall thickness and mass. Systolic function was normal and diastolic function was normal or supernormal (increased ratio of rapid to atrial LV filling velocities). The finding of a pattern of concentric hypertrophy was reinforced by a close relationship between submaximal exercise systolic blood pressure and LV mass (r = 0.88). Examination of valvular function by Doppler ultrasound revealed significantly increased prevalences of mitral and tricuspid regurgitation in athletes, with 91% of athletes (vs 38% of controls) having regurgitation detected in at least one cardiac valve. Analysis of athletes using standard electrocardiographic criteria for the detection of left ventricular hypertrophy showed that these criteria did not reliably detect increased mass. However, changes such as marked QRS prolongation and nonvoltage criteria for LV hypertrophy and RV hypertrophy may be useful in separating physiologic from pathologic hypertrophy. Our studies provide additional descriptions of cardiac changes produced by ultraendurance exercise training and suggest that the hemodynamic load imposed by exercise may be a contributing cause to physiologic hypertrophy. Much yet remains to be learned about the cardiac adaptation to exercise training.

Positron Emission Tomography for the Assessment of Myocardial Viability

PubMed Central

2005-01-01

Executive Summary Objective The objective was to update the 2001 systematic review conducted by the Institute For Clinical Evaluative Sciences (ICES) on the use of positron emission tomography (PET) in assessing myocardial viability. The update consisted of a review and analysis of the research evidence published since the 2001 ICES review to determine the effectiveness and cost-effectiveness of PET in detecting left ventricular (LV) viability and predicting patient outcomes after revascularization in comparison with other noninvasive techniques. Background Left Ventricular Viability Heart failure is a complex syndrome that impairs the contractile ability of the heart to maintain adequate blood circulation, resulting in poor functional capacity and increased risk of morbidity and mortality. It is the leading cause of hospitalization in elderly Canadians. In more than two-thirds of cases, heart failure is secondary to coronary heart disease. It has been shown that dysfunctional myocardium resulting from coronary heart disease (CAD) may recover contractile function (i.e. considered viable). Dysfunctional but viable myocardium may have been stunned by a brief episode of ischemia, followed by restoration of perfusion, and may regain function spontaneously. It is believed that repetitive stunning results in hibernating myocardium that will only regain contractile function upon revascularization. For people with CAD and severe LV dysfunction (left ventricular ejection fraction [LVEF] <35%) refractory to medical therapy, coronary artery bypass and heart transplantation are the only treatment options. The opportunity for a heart transplant is limited by scarcityof donor hearts. Coronary artery bypass in these patients is associated with high perioperative complications; however, there is evidence that revascularization in the presence of dysfunctional but viable myocardium is associated with survival benefits and lower rates of cardiac events. The assessment of left ventricular (LV) viability is, therefore, critical in deciding whether a patient with coronary artery disease and severe LV dysfunction should undergo revascularization, receive a heart transplant, or remain on medical therapy. Assessment of Left Ventricular Viability Techniques for assessing myocardial viability depend on the measurement of a specific characteristic of viable myocytes such as cell membrane integrity, preserved metabolism, mitochondria integrity, and preserved contractile reserve. In Ontario, single photon emission computed tomography (SPECT) using radioactive 201thallium is the most commonly used technique followed by dobutamine echocardiography. Newer techniques include SPECT using technetium tracers, cardiac magnetic resonance imaging, and PET, the subject of this review. Positron Emission Tomography PET is a nuclear imaging technique based on the metabolism of radioactive analogs of normal substrates such as glucose and water. The radiopharmaceutical used most frequently in myocardial viability assessment is F18 fluorodeoxyglucose (FDG), a glucose analog. The procedure involves the intravenous administration of FDG under controlled glycemic conditions, and imaging with a PET scanner. The images are reconstructed using computer software and analyzed visually or semi-quantitatively, often in conjunction with perfusion images. Dysfunctional but stunned myocardium is characterized by normal perfusion and normal FDG uptake; hibernating myocardium exhibits reduced perfusion and normal/enhanced FDG uptake (perfusion/metabolism mismatch), whereas scar tissue is characterized by reduction in both perfusion and FDG uptake (perfusion/metabolism match). Review Strategy The Medical Advisory Secretariat used a search strategy similar to that used in the 2001 ICES review to identify English language reports of health technology assessments and primary studies in selected databases, published from January 1, 2001 to April 20, 2005. Patients of interest were those with CAD and severe ventricular dysfunction being considered for revascularization that had undergone viability assessment using either PET and/or other noninvasive techniques. The outcomes of interest were diagnostic and predictive accuracy with respect to recovery of regional or global LV function, long-term survival and cardiac events, and quality of life. Other outcomes of interest were impact on treatment decision, adverse events, and cost-effectiveness ratios. Of 456 citations, 8 systematic reviews/meta-analyses and 37 reports on primary studies met the selection criteria. The reports were categorized using the Medical Advisory Secretariat levels of evidence system, and the quality of the reports was assessed using the criteria of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) developed by the Centre for Dissemination of Research (National Health Service, United Kingdom). Analysis of sensitivity, specificity, predictive values and likelihood ratios were conducted for all data as well as stratified by mean left ventricular ejection fraction (LVEF). There were no randomized controlled trials. The included studies compared PET with one or more other noninvasive viability tests on the same group of patients or examined the long-term outcomes of PET viability assessments. The quality assessment showed that about 50% or more of the studies had selection bias, interpreted tests without blinding, excluded uninterpretable segments in the analysis, or did not have clearly stated selection criteria. Data from the above studies were integrated with data from the 2001 ICES review for analysis and interpretation. Summary of Findings The evidence was derived from populations with moderate to severe ischemic LV dysfunction with an overall quality that ranges from moderate to low. PET appears to be a safe technique for assessing myocardial viability. CAD patients with moderate to severe ischemic LV dysfunction and residual viable myocardium had significantly lower 2-year mortality rate (3.2%) and higher event-free survival rates (92% at 3 years) when treated with revascularization than those who were not revascularized but were treated medically (16% mortality at 2-years and 48% 3-year event-free survival). A large meta-analysis and moderate quality studies of diagnostic accuracy consistently showed that compared to other noninvasive diagnostic tests such as thallium SPECT and echocardiography, FDG PET has: Higher sensitivity (median 90%, range 71%–100%) and better negative likelihood ratio (median 0.16, range 0–0.38; ideal <0.1) for predicting regional myocardial function recovery after revascularization. Specificity (median 73%, range 33%–91%) that is similar to other radionuclide imaging but lower than that of dobutamine echocardiography Less useful positive likelihood ratio (median 3.1, range 1.4 –9.2; ideal>10) for predicting segmental function recovery. Taking positive and negative likelihood ratios together suggests that FDG PET and dobutamine echocardiography may produce small but sometimes important changes in the probability of recovering regional wall motion after revascularization. Given its higher sensitivity, PET is less likely to produce false positive results in myocardial viability. PET, therefore, has the potential to identify some patients who might benefit from revascularization, but who would not have been identified as suitable candidates for revascularization using thallium SPECT or dobutamine echocardiography. PET appears to be superior to other nuclear imaging techniques including SPECT with 201thallium or technetium labelled tracers, although recent studies suggest that FDG SPECT may have comparable diagnostic accuracy as FDG PET for predicting regional and global LV function recovery. No firm conclusion can be reached about the incremental value of PET over other noninvasive techniques for predicting global function improvement or long-term outcomes in the most important target population (patients with severe ischemic LV dysfunction) due to lack of direct comparison. An Ontario-based economic analysis showed that in people with CAD and severe LV dysfunction and who were found to have no viable myocardium or indeterminate results by thallium SPECT, the use of PET as a follow-up assessment would likely result in lower cost and better 5-year survival compared to the use of thallium SPECT alone. The projected annual budget impact of adding PET under the above scenario was estimated to range from $1.5 million to $2.3 million. Conclusion In patients with severe LV dysfunction, that are deemed to have no viable myocardium or indeterminate results in assessments using other noninvasive tests, PET may have a role in further identifying patients who may benefit from revascularization. No firm conclusion can be drawn on the impact of PET viability assessment on long-term clinical outcomes in the most important target population (i.e. patients with severe LV dysfunction). PMID:23074467

Strong seismic wave scattering beneath Kanto region derived from dense K-NET/KiK-net strong motion network and numerical simulation

NASA Astrophysics Data System (ADS)

Takemura, S.; Yoshimoto, K.

2013-12-01

Observed seismograms, which consist of the high-frequency body waves through the low-velocity (LV) region at depth of 20-40 km beneath northwestern Chiba in Kanto, show strong peak delay and spindle shape of S waves. By analyzing dense seismic records from K-NET/KiK-net, such spindle-shape S waves are clearly observed in the frequency range of 1-8 Hz. In order to investigate a specific heterogeneous structure to generate such observations, we conduct 3-D finite-difference method (FDM) simulation using realistic heterogeneous models and compare the simulation results with dense strong motion array observations. Our 3-D simulation model is covering the zone 150 km by 64 km in horizontal directions and 75 km in vertical direction, which has been discretized with uniform grid size 0.05 km. We assume a layered background velocity structure, which includes basin structure, crust, mantle and subducting oceanic plate, base on the model proposed by Koketsu et al. (2008). In order to introduce the effect of seismic wave scattering, we assume a stochastic random velocity fluctuation in each layer. Random velocity fluctuations are characterized by exponential-type auto-correlation function (ACF) with correlation distance a = 3 km and rms value of fluctuation e = 0.05 in the upper crust, a = 3 km and e = 0.07 in the lower crust, a = 10 km and e = 0.02 in the mantle. In the subducting oceanic plate, we assume an anisotropic random velocity fluctuation characterized by exponential-type ACF with aH = 10 km in horizontal direction, aZ = 0.5 km in vertical direction and e = 0.02 (e.g., Furumura and Kennett, 2005). In addition, we assume a LV zone at northeastern part of Chiba with depth of 20-40 km (e.g., Matsubara et al., 2004). In the LV zone, random velocity fluctuation characterized by Gaussian-type ACF with a = 1 km and e = 0.07 is superposed on exponential-type ACF with a = 3 km and e = 0.07, in order to modulate the S-wave propagation in the dominant frequency range of spindle-shape S waves. Such large-scale FDM simulations are conducted on the Earth Simulator at JAMSTEC. It is found that the FDM simulation of the model without strong velocity fluctuation cannot explain the characteristics of observed S waves. By introducing strong velocity fluctuation in the LV zone, strong peak delay and spindle-shape S waves observed at central and southern part of Chiba are simulated successfully. In addition, the strong amplitude decrease of S waves in the LV zone due to strong seismic scattering is good corresponding to results based on the tomographic study of Q in Kanto (e.g., Nakamura et al., 2006). Simulation results demonstrated that strong velocity fluctuation in the LV zone plays important role in the peak delay and waveform shape. The LV zone beneath northeastern Chiba is considered as a result of dehydration from oceanic crust of subducted Philippine Sea plate (e.g., Matsubara et al., 2005). Therefore strong small-scale velocity fluctuation in the LV zone may be related with dehydrated water.

Advanced two-layer level set with a soft distance constraint for dual surfaces segmentation in medical images

NASA Astrophysics Data System (ADS)

Ji, Yuanbo; van der Geest, Rob J.; Nazarian, Saman; Lelieveldt, Boudewijn P. F.; Tao, Qian

2018-03-01

Anatomical objects in medical images very often have dual contours or surfaces that are highly correlated. Manually segmenting both of them by following local image details is tedious and subjective. In this study, we proposed a two-layer region-based level set method with a soft distance constraint, which not only regularizes the level set evolution at two levels, but also imposes prior information on wall thickness in an effective manner. By updating the level set function and distance constraint functions alternatingly, the method simultaneously optimizes both contours while regularizing their distance. The method was applied to segment the inner and outer wall of both left atrium (LA) and left ventricle (LV) from MR images, using a rough initialization from inside the blood pool. Compared to manual annotation from experience observers, the proposed method achieved an average perpendicular distance (APD) of less than 1mm for the LA segmentation, and less than 1.5mm for the LV segmentation, at both inner and outer contours. The method can be used as a practical tool for fast and accurate dual wall annotations given proper initialization.

Development of a multiplex amplification refractory mutation system reverse transcription polymerase chain reaction assay for the differential diagnosis of Feline leukemia virus vaccine and wild strains.

PubMed

Ho, Chia-Fang; Chan, Kun-Wei; Yang, Wei-Cheng; Chiang, Yu-Chung; Chung, Yang-Tsung; Kuo, James; Wang, Chi-Young

2014-07-01

A multiplex amplification refractory mutation system reverse transcription polymerase chain reaction (ARMS RT-PCR) was developed for the differential diagnosis of Feline leukemia virus (FeLV) vaccine and wild-type strains based on a point mutation between the vaccine strain (S) and the wild-type strain (T) located in the p27 gene. This system was further upgraded to obtain a real-time ARMS RT-PCR (ARMS qRT-PCR) with a high-resolution melt analysis (HRMA) platform. The genotyping of various strains of FeLV was determined by comparing the HRMA curves with the defined wild-type FeLV (strain TW1), and the results were expressed as a percentage confidence. The detection limits of ARMS RT-PCR and ARMS qRT-PCR combined with HRMA were 100 and 1 copies of transcribed FeLV RNA per 0.5 ml of sample, respectively. No false-positive results were obtained with 6 unrelated pathogens and 1 feline cell line. Twelve FeLV Taiwan strains were correctly identified using ARMS qRT-PCR combined with HRMA. The genotypes of the strains matched the defined FeLV wild-type strain genotype with at least 91.17% confidence. A higher degree of sequence polymorphism was found throughout the p27 gene compared with the long terminal repeat region. In conclusion, the current study describes the phylogenetic relationship of the FeLV Taiwan strains and demonstrates that the developed ARMS RT-PCR assay is able to be used to detect the replication of a vaccine strain that has not been properly inactivated, thus acting as a safety check for the quality of FeLV vaccines.

Clinical Characteristics and Outcomes of Patients with Amphetamine-Associated Cardiomyopathy in South Auckland, New Zealand.

PubMed

Kueh, Shaw-Hua Anthony; Gabriel, Ruvin S; Lund, Mayanna; Sutton, Tim; Bradley, Joshua; Kerr, Andrew J; Looi, Jen-Li

2016-11-01

Amphetamine-associated cardiomyopathy (AAC) is becoming an increasingly recognised entity. The characteristics and outcomes of these patients are poorly understood. Thirty patients admitted with heart failure and echocardiographic evidence of cardiomyopathy between 2005 and 2014 and who had a documented history of amphetamine abuse that was considered an important factor in the causation of their cardiomyopathy were retrospectively identified. Mean age at presentation was 40±10 years with a male predominance (n=25, 83%). The majority were of indigenous Maori ethnicity. At presentation, four patients were in cardiogenic shock. Five patients required intensive care unit (ICU) admission for inotropic support and mechanical ventilation. Fifteen had severe left ventricular (LV) dilation (mean LV end-diastolic dimension 6.8±1.0cm) and all patients had severe LV dysfunction (mean LV ejection fraction 22±8%). Despite optimal heart failure therapy, LV size remained significantly dilated with minimal improvement in LV function. During median follow-up of 18 months, five patients died from end-stage heart failure and 17 had at least one readmission with decompensated heart failure. Amphetamine-associated cardiomyopathy was seen predominantly in young indigenous Maori men. They presented with severe cardiomyopathy, often requiring ICU admission. Severe LV dilation and significant LV dysfunction persisted despite treatment and mortality was high. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Left ventricular stiffness estimated by diastolic wall strain is associated with paroxysmal atrial fibrillation in structurally normal hearts.

PubMed

Uetake, Shunsuke; Maruyama, Mitsunori; Yamamoto, Teppei; Kato, Katsuhito; Miyauchi, Yasushi; Seino, Yoshihiko; Shimizu, Wataru

2016-12-01

Left ventricular (LV) diastolic dysfunction depends on an impaired relaxation and stiffness. Abnormal LV relaxation contributes to the development of atrial fibrillation (AF), but the role of LV stiffness in AF remains unclear. Diastolic wall strain (DWS), a load-independent, noninvasive direct measure of LV stiffness, correlates with prevalent AF. This study included 328 consecutive subjects with structurally normal hearts: 164 paroxysmal AF patients and 164 age- and sex-matched (1:1) controls. We calculated the DWS from the M-mode echocardiographic measurements of the LV posterior wall thickness at end-systole and end-diastole during sinus rhythm. The DWS was lower in the AF patients (0.35 ± 0.07) than in the controls (0.41 ± 0.06; P < 0.001). After adjusting for the risk factors of AF using a conditional logistic regression analysis, a history of hypertension, plasma brain-type natriuretic peptide level, and DWS were independently associated with AF prevalence, whereas body mass index, LV mass index, left atrial volume, and any conventional indices of the diastolic function were not. A low DWS (<0.380) was the strongest indicator of AF (odds ratio: 6.22, 95% confidence interval: 3.08-14.2, P < 0.001). Increased LV stiffness estimated by DWS was a strong determinant of the prevalence of AF. LV stiffness may play a role in the pathogenesis of paroxysmal AF in structurally normal hearts. © 2016 Wiley Periodicals, Inc.

Left Ventricular Function Across the Spectrum of Body Mass Index in African Americans: The Jackson Heart Study.

PubMed

Patel, Vivek G; Gupta, Deepak K; Terry, James G; Kabagambe, Edmond K; Wang, Thomas J; Correa, Aldolfo; Griswold, Michael; Taylor, Herman; Carr, John Jeffrey

2017-03-01

This study sought to assess whether body mass index (BMI) was associated with subclinical left ventricular (LV) systolic dysfunction in African-American individuals. Higher BMI is a risk factor for cardiovascular disease, including heart failure. Obesity disproportionately affects African Americans; however, the association between higher BMI and LV function in African Americans is not well understood. Peak systolic circumferential strain (ECC) was measured by tagged cardiac magnetic resonance in 1,652 adult African-American participants of the Jackson Heart Study between 2008 and 2012. We evaluated the association between BMI and ECC in multivariate linear regression and restricted cubic spline analyses adjusted for prevalent cardiovascular disease, conventional cardiovascular risk factors, LV mass, and ejection fraction. In exploratory analyses, we also examined whether inflammation, insulin resistance, or volume of visceral adipose tissue altered the association between BMI and ECC. The proportions of female, nonsmokers, diabetic, and hypertensive participants rose with increase in BMI. In multivariate-adjusted models, higher BMI was associated with worse ECC (β = 0.052; 95% confidence interval: 0.028 to 0.075), even in the setting of preserved LV ejection fraction. Higher BMI was also associated with worse ECC when accounting for markers of inflammation (C-reactive protein, E-selection, and P-selectin), insulin resistance, and volume of visceral adipose tissue. Higher BMI is significantly associated with subclinical LV dysfunction in African Americans, even in the setting of preserved LV ejection fraction. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Impaired myocardial function does not explain reduced left ventricular filling and stroke volume at rest or during exercise at high altitude

PubMed Central

Ainslie, Philip N.; Hughes, Michael G.; Stöhr, Eric J.; Cotter, James D.; Tymko, Michael M.; Day, Trevor A.; Bakker, Akke; Shave, Rob

2015-01-01

Impaired myocardial systolic contraction and diastolic relaxation have been suggested as possible mechanisms contributing to the decreased stroke volume (SV) observed at high altitude (HA). To determine whether intrinsic myocardial performance is a limiting factor in the generation of SV at HA, we assessed left ventricular (LV) systolic and diastolic mechanics and volumes in 10 healthy participants (aged 32 ± 7; mean ± SD) at rest and during exercise at sea level (SL; 344 m) and after 10 days at 5,050 m. In contrast to SL, LV end-diastolic volume was ∼19% lower at rest (P = 0.004) and did not increase during exercise despite a greater untwisting velocity. Furthermore, resting SV was lower at HA (∼17%; 60 ± 10 vs. 70 ± 8 ml) despite higher LV twist (43%), apical rotation (115%), and circumferential strain (17%). With exercise at HA, the increase in SV was limited (12 vs. 22 ml at SL), and LV apical rotation failed to augment. For the first time, we have demonstrated that EDV does not increase upon exercise at high altitude despite enhanced in vivo diastolic relaxation. The increase in LV mechanics at rest may represent a mechanism by which SV is defended in the presence of a reduced EDV. However, likely because of the higher LV mechanics at rest, no further increase was observed up to 50% peak power. Consequently, although hypoxia does not suppress systolic function per se, the capacity to increase SV through greater deformation during submaximal exercise at HA is restricted. PMID:25749445

The Romhilt-Estes electrocardiographic score predicts sudden cardiac arrest independent of left ventricular mass and ejection fraction.

PubMed

Darouian, Navid; Aro, Aapo L; Narayanan, Kumar; Uy-Evanado, Audrey; Rusinaru, Carmen; Reinier, Kyndaron; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S

2017-07-01

The Romhilt-Estes point score system (RE) is an established ECG criterion for diagnosing left ventricular hypertrophy (LVH). In this study, we assessed for the first time, whether RE and its components are predictive of sudden cardiac arrest (SCA) independent of left ventricular (LV) mass. Sudden cardiac arrest (SCA) cases occurring between 2002 and 2014 in a Northwestern US metro region (catchment area approx. 1 million) were compared to geographic controls. ECGs and echocardiograms performed prior to the SCA and those of controls were acquired from the medical records and evaluated for the ECG criteria established in the RE score and for LV mass. Two hundred forty-seven SCA cases (age 68.3 ± 14.6, male 64.4%) and 330 controls (age 67.4 ± 11.5, male 63.6) were included in the analysis. RE scores were greater in cases than controls (2.5 ± 2.1 vs. 1.9 ± 1.7, p < .001), and SCA cases were more likely to meet definite LVH criteria (18.6% vs. 7.9%, p < .001). In a multivariable model including echocardiographic LVH and LV function, definite LVH remained independently predictive of SCA (OR 2.04, 95% CI 1.16-3.59, p = .013). The model was replicated with the individual ECG criteria, and only SV 1.2  ≥ 30 mm and delayed intrinsicoid deflection remained significant predictors of SCA. Left ventricular hypertrophy (LVH) as defined by the RE point score system is associated with SCA independent of echocardiographic LVH and reduced LV ejection fraction. These findings support an independent role for purely electrical LVH, in the genesis of lethal ventricular arrhythmias. © 2017 Wiley Periodicals, Inc.

DDD(R)-pacing, but not AAI(R)-pacing induces left ventricular desynchronization in patients with sick sinus syndrome: tissue-Doppler and 3D echocardiographic evaluation in a randomized controlled comparison.

PubMed

Albertsen, Andi Eie; Nielsen, Jens Cosedis; Poulsen, Steen Hvitfeldt; Mortensen, Peter Thomas; Pedersen, Anders Kirstein; Hansen, Peter Steen; Jensen, Henrik Kjaerulf; Egeblad, Henrik

2008-02-01

Increasing evidence from randomized trials and experimental studies indicates that right ventricular (RV) pacing may induce congestive heart failure. We studied regional left ventricular (LV) dyssynchrony and global LV function in 50 consecutive patients with sick sinus syndrome (SSS) randomized to either atrial pacing [AAI(R)] or dual chamber RV-pacing [DDD(R)]. Fifty consecutive patients were randomized to AAI(R) or DDD(R)-pacing. Tissue-Doppler imaging was used to quantify LV dyssynchrony in terms of number of segments with delayed longitudinal contraction (DLC). Left ventricular ejection fraction (LVEF) was measured using three-dimensional echocardiography. Dyssynchrony was more pronounced in the DDD(R)-group than in the AAI(R)-group at the 12 months follow-up (P < 0.05). This reflected a significant increase of dyssynchrony in the DDD(R)-group from baseline to the 12 months follow-up (1.3 +/- 1 to 2.1 +/- 1 segments displaying DLC per patient), P < 0.05. No change was observed in the AAI(R)-group (1.6 +/- 2 to 1.3 +/- 2 segments displaying DLC per patient, NS). No difference in LVEF, NYHA or NT-proBNP was observed between AAI(R)- and DDD(R)-mode after 12 months of pacing although LVEF decreased significantly in the DDD(R)-group from baseline (63.1 +/- 8%) to the 12 months follow-up (59.3 +/- 8%, P < 0.05), while LVEF remained unchanged in the AAI(R)-group (61.5 +/- 11% at baseline vs. 62.3 +/- 7% after 12 months, NS. In patients with SSS, DDD(R)-pacing but not AAI(R)-pacing induces significant LV desynchronization and reduction of LVEF.

The agreement between 3D, standard 2D and triplane 2D speckle tracking: effects of image quality and 3D volume rate.

PubMed

Trache, Tudor; Stöbe, Stephan; Tarr, Adrienn; Pfeiffer, Dietrich; Hagendorff, Andreas

2014-12-01

Comparison of 3D and 2D speckle tracking performed on standard 2D and triplane 2D datasets of normal and pathological left ventricular (LV) wall-motion patterns with a focus on the effect that 3D volume rate (3DVR), image quality and tracking artifacts have on the agreement between 2D and 3D speckle tracking. 37 patients with normal LV function and 18 patients with ischaemic wall-motion abnormalities underwent 2D and 3D echocardiography, followed by offline speckle tracking measurements. The values of 3D global, regional and segmental strain were compared with the standard 2D and triplane 2D strain values. Correlation analysis with the LV ejection fraction (LVEF) was also performed. The 3D and 2D global strain values correlated good in both normally and abnormally contracting hearts, though systematic differences between the two methods were observed. Of the 3D strain parameters, the area strain showed the best correlation with the LVEF. The numerical agreement of 3D and 2D analyses varied significantly with the volume rate and image quality of the 3D datasets. The highest correlation between 2D and 3D peak systolic strain values was found between 3D area and standard 2D longitudinal strain. Regional wall-motion abnormalities were similarly detected by 2D and 3D speckle tracking. 2DST of triplane datasets showed similar results to those of conventional 2D datasets. 2D and 3D speckle tracking similarly detect normal and pathological wall-motion patterns. Limited image quality has a significant impact on the agreement between 3D and 2D numerical strain values.

Validating a new methodology for strain estimation from cardiac cine MRI

NASA Astrophysics Data System (ADS)

Elnakib, Ahmed; Beache, Garth M.; Gimel'farb, Georgy; Inanc, Tamer; El-Baz, Ayman

2013-10-01

This paper focuses on validating a novel framework for estimating the functional strain from cine cardiac magnetic resonance imaging (CMRI). The framework consists of three processing steps. First, the left ventricle (LV) wall borders are segmented using a level-set based deformable model. Second, the points on the wall borders are tracked during the cardiac cycle based on solving the Laplace equation between the LV edges. Finally, the circumferential and radial strains are estimated at the inner, mid-wall, and outer borders of the LV wall. The proposed framework is validated using synthetic phantoms of the material strains that account for the physiological features and the LV response during the cardiac cycle. Experimental results on simulated phantom images confirm the accuracy and robustness of our method.

Phylogenetic and Molecular Variability Studies Reveal a New Genetic Clade of Citrus leprosis virus C

PubMed Central

Ramos-González, Pedro Luis; Chabi-Jesus, Camila; Guerra-Peraza, Orlene; Breton, Michèle Claire; Arena, Gabriella Dias; Nunes, Maria Andreia; Kitajima, Elliot Watanabe; Machado, Marcos Antonio; Freitas-Astúa, Juliana

2016-01-01

Citrus leprosis virus C (CiLV-C) causes a severe disease affecting citrus orchards in the Western hemisphere. This study reveals the molecular variability of the virus by analyzing four genomic regions (p29, p15, MP and RNA2-intergenic region) distributed over its two RNAs. Nucleotide diversity (π) values were relatively low but statistically different over the analyzed genes and subpopulations, indicating their distinct evolutionary history. Values of πp29 and πMP were higher than those of πp15 and πRNA2–IR, whereas πMP was increased due to novel discovered isolates phylogenetically clustered in a divergent clade that we called SJP. Isolate BR_SP_SJP_01 RNA1 and RNA2 sequences, clade SJP, showed an identity of 85.6% and 88.4%, respectively, with those corresponding to CiLV-C, the type member of the genus Cilevirus, and its RNA2 5′-proximal region was revealed as a minor donor in a putative inter-clade recombination event. In addition to citrus, BR_SP_SJP_01 naturally infects the weed Commelina benghalensis and is efficiently transmitted by Brevipalpus yothersi mites. Our data demonstrated that negative selection was the major force operating in the evaluated viral coding regions and defined amino acids putatively relevant for the biological function of cilevirus proteins. This work provides molecular tools and sets up a framework for further epidemiological studies. PMID:27275832

Kidney Disease Measures and Left Ventricular Structure and Function: The Atherosclerosis Risk in Communities Study.

PubMed

Matsushita, Kunihiro; Kwak, Lucia; Sang, Yingying; Ballew, Shoshana H; Skali, Hicham; Shah, Amil M; Coresh, Josef; Solomon, Scott

2017-09-22

Heart failure is one of the most important complications of chronic kidney disease (CKD). However, few studies comprehensively investigated left ventricular (LV) structure and function in relation to 2 key CKD measures, estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (ACR). Among 4175 ARIC (Atherosclerosis Risk in Communities) participants (aged 66-90 years during 2011-2013), we quantified the association of eGFR and ACR with echocardiogram parameters of LV mass, size, systolic function, and diastolic function. Adjusting for demographic variables, both CKD measures were significantly associated with most echocardiogram parameters. Additionally accounting for other potential confounders, we observed significantly higher LV mass index according to reduced eGFR (82.3 [95% confidence interval (CI), 77.6-87.0] g/m 2 for eGFR <30 mL/min per 1.73 m 2 , 80.9 [95% CI, 77.3-84.6] g/m 2 for eGFR 30-44 mL/min per 1.73 m 2 , and 80.1 [95% CI, 76.7-83.5] g/m 2 for eGFR 45-59 mL/min per 1.73 m 2 compared with 78.7 [95% CI, 75.3-82.1] g/m 2 for eGFR 75-89 mL/min per 1.73 m 2 ; trend P <0.001). Regarding LV size and function, significant differences were observed for some parameters, particularly at eGFR <30 mL/min per 1.73 m 2 . For ACR, the associations remained significant for most parameters (eg, LV mass index, 91.5 [95% CI, 86.6-96.5] g/m 2 for ACR ≥300 mg/g and 82.9 [95% CI, 79.4-86.3] g/m 2 for ACR 30-299 mg/g compared with 77.7 [95% CI, 74.4-81.1] g/m 2 for ACR <10 mg/g [trend P <0.001]; left arterial volume index, 24.9 [95% CI, 22.9-26.8] and 24.7 [95% CI, 23.4-26.1] mL/m 2 compared with 23.4 [95% CI, 22.1-24.7] mL/m 2 , respectively [trend P =0.010]). Dichotomizing echo parameters with clinical thresholds, the stronger relationships of ACR over eGFR were further evident. LV mass was related to both CKD measures, whereas LV size and function were robustly associated with albuminuria. These results have implications for pathophysiological processes behind cardiorenal syndrome and targeted cardiac assessment in patients with CKD. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Preliminary rotor wake measurements with a laser velocimeter

NASA Technical Reports Server (NTRS)

Hoad, D. R.; Rhodes, D. B.; Meyers, J. F.

1983-01-01

A laser velocimeter (LV) was used to determine rotor wake characteristics. The effect of various fuselage widths and rotor-fuselage spacings on time averaged and detailed time dependent rotor wake velocity characteristics was defined. Definition of time dependent velocity characteristics was attempted with the LV by associating a rotor azimuth position with each velocity measurement. Results were discouraging in that no apparent time dependent velocity characteristics could be discerned from the LV measurements. Since the LV is a relatively new instrument in the rotor wake measurement field, the cause of this lack of periodicity is as important as the basic research objectives. An attempt was made to identify the problem by simulated acquisition of LV-type data for a predicted rotor wake velocity time history. Power spectral density and autocorrelation function estimation techniques were used to substantiate the conclusion that the primary cause of the lack of time dependent velocity characteristics was the nonstationary flow condition generated by the periodic turbulence level that currently exists in the open throat configuration of the wind tunnel.

Ventricular Geometry From Non-contrast Non-ECG-gated CT Scans: An Imaging Marker of Cardiopulmonary Disease in Smokers.

PubMed

Rahaghi, Farbod N; Vegas-Sanchez-Ferrero, Gonzalo; Minhas, Jasleen K; Come, Carolyn E; De La Bruere, Isaac; Wells, James M; González, Germán; Bhatt, Surya P; Fenster, Brett E; Diaz, Alejandro A; Kohli, Puja; Ross, James C; Lynch, David A; Dransfield, Mark T; Bowler, Russel P; Ledesma-Carbayo, Maria J; San José Estépar, Raúl; Washko, George R

2017-05-01

Imaging-based assessment of cardiovascular structure and function provides clinically relevant information in smokers. Non-cardiac-gated thoracic computed tomographic (CT) scanning is increasingly leveraged for clinical care and lung cancer screening. We sought to determine if more comprehensive measures of ventricular geometry could be obtained from CT using an atlas-based surface model of the heart. Subcohorts of 24 subjects with cardiac magnetic resonance imaging (MRI) and 262 subjects with echocardiography were identified from COPDGene, a longitudinal observational study of smokers. A surface model of the heart was manually initialized, and then automatically optimized to fit the epicardium for each CT. Estimates of right and left ventricular (RV and LV) volume and free-wall curvature were then calculated and compared to structural and functional metrics obtained from MRI and echocardiograms. CT measures of RV dimension and curvature correlated with similar measures obtained using MRI. RV and LV volume obtained from CT inversely correlated with echocardiogram-based estimates of RV systolic pressure using tricuspid regurgitation jet velocity and LV ejection fraction respectively. Patients with evidence of RV or LV dysfunction on echocardiogram had larger RV and LV dimensions on CT. Logistic regression models based on demographics and ventricular measures from CT had an area under the curve of >0.7 for the prediction of elevated right ventricular systolic pressure and ventricular failure. These data suggest that non-cardiac-gated, non-contrast-enhanced thoracic CT scanning may provide insight into cardiac structure and function in smokers. Copyright © 2017. Published by Elsevier Inc.

Enforced IL-10 Expression Confers Type 1 Regulatory T Cell (Tr1) Phenotype and Function to Human CD4+ T Cells

PubMed Central

Andolfi, Grazia; Fousteri, Georgia; Rossetti, Maura; Magnani, Chiara F; Jofra, Tatiana; Locafaro, Grazia; Bondanza, Attilio; Gregori, Silvia; Roncarolo, Maria-Grazia

2012-01-01

Type 1 regulatory T (Tr1) cells are an inducible subset of CD4+ Tr cells characterized by high levels of interleukin (IL)-10 production and regulatory properties. Several protocols to generate human Tr1 cells have been developed in vitro. However, the resulting population includes a significant fraction of contaminating non-Tr1 cells, representing a major bottleneck for clinical application of Tr1 cell therapy. We generated an homogeneous IL-10–producing Tr1 cell population by transducing human CD4+ T cells with a bidirectional lentiviral vector (LV) encoding for human IL-10 and the marker gene, green fluorescent protein (GFP), which are independently coexpressed. The resulting GFP+ LV-IL-10–transduced human CD4+ T (CD4LV-IL-10) cells expressed, upon T-cell receptor (TCR) activation, high levels of IL-10 and concomitant low levels of IL-4, and markers associated with IL-10. Moreover, CD4LV-IL-10 T cells displayed typical Tr1 features: the anergic phenotype, the IL-10, and transforming growth factor (TGF)-β dependent suppression of allogeneic T-cell responses, and the ability to suppress in a cell-to-cell contact independent manner in vitro. CD4LV-IL-10 T cells were able to control xeno graft-versus-host disease (GvHD), demonstrating their suppressive function in vivo. These results show that constitutive over-expression of IL-10 in human CD4+ T cells leads to a stable cell population that recapitulates the phenotype and function of Tr1 cells. PMID:22692497

Doppler Assessment of Diastolic Function Reflect the Severity of Injury in Rats With Chronic Heart Failure.

PubMed

Sanchez, Pablo; Lancaster, Jordan J; Weigand, Kyle; Mohran, Saffie-Alrahman Ezz-Eldin; Goldman, Steven; Juneman, Elizabeth

2017-10-01

For chronic heart failure (CHF), more emphasis has been placed on evaluation of systolic as opposed to diastolic function. Within the study of diastology, measurements of left ventricular (LV) longitudinal myocardial relaxation have the most validation. Anterior wall radial myocardial tissue relaxation velocities along with mitral valve inflow (MVI) patterns are applicable diastolic parameters in the differentiation between moderate and severe disease in the ischemic rat model of CHF. Myocardial tissue relaxation velocities correlate with traditional measurements of diastolic function (ie, hemodynamics, Tau, and diastolic pressure-volume relationships). Male Sprague-Dawley rats underwent left coronary artery ligation or sham operation. Echocardiography was performed at 3 and 6 weeks after coronary ligation to evaluate LV ejection fraction (EF) and LV diastolic function through MVI patterns (E, A, and E/A) and Doppler imaging of the anterior wall (e' and a'). The rats were categorized into moderate or severe CHF according to their LV EF at 3 weeks postligation. Invasive hemodynamic measurements with solid-state pressure catheters were obtained at the 6-week endpoint. Moderate (N = 20) and severe CHF (N = 22) rats had significantly (P < .05) different EFs, hemodynamics, and diastolic pressure-volume relationships. Early diastolic anterior wall radial relaxation velocities as well as E/e' ratios separated moderate from severe CHF and both diastolic parameters had strong correlations with invasive hemodynamic measurements of diastolic function. Radial anterior wall e' and E/e' can be used for serial assessment of diastolic function in rats with moderate and severe CHF. Copyright © 2017 Elsevier Inc. All rights reserved.

Correlation of trabeculae and papillary muscles with clinical and cardiac characteristics and impact on CMR measures of LV anatomy and function.

PubMed

Chuang, Michael L; Gona, Philimon; Hautvast, Gilion L T F; Salton, Carol J; Blease, Susan J; Yeon, Susan B; Breeuwer, Marcel; O'Donnell, Christopher J; Manning, Warren J

2012-11-01

The goal of this study was to assess the relationship of left ventricular (LV) trabeculae and papillary muscles (TPM) with clinical characteristics in a community-based, free-living adult cohort and to determine the effect of TPM on quantitative measures of LV volume, mass, and ejection fraction (EF). Hypertrabeculation has been associated with adverse cardiovascular events, but the distribution and clinical correlates of the volume and mass of the TPM in a normal left ventricle have not been well characterized. Short-axis cine cardiac magnetic resonance images, obtained using a steady-state free precession sequence from 1,494 members of the Framingham Heart Study Offspring cohort, were analyzed with software that automatically segments TPM. Absolute TPM volume, TPM as a fraction of end-diastolic volume (EDV) (TPM/EDV), and TPM mass as a fraction of LV mass were determined in all offspring and in a referent group of offspring free of clinical cardiovascular disease and hypertension. In the referent group (mean age 61 ± 9 years; 262 men and 423 women), mean TPM was 23 ± 3% of LV EDV in both sexes (p = 0.9). TPM/EDV decreased with age (p < 0.02) but was not associated with body mass index. TPM mass as a fraction of LV mass was inversely correlated with age (p < 0.0001), body mass index (p < 0.018), and systolic blood pressure (p < 0.0001). Among all 1,494 participants (699 men), LV volumes decreased 23%, LV mass increased 28%, and EF increased by 7.5 EF units (p < 0.0001) when TPM were considered myocardial mass rather than part of the LV blood pool. Global cardiac magnetic resonance LV parameters were significantly affected by whether TPM was considered as part of the LV blood pool or as part of LV mass. Our cross-sectional data from a healthy referent group of adults free of clinical cardiovascular disease demonstrated that TPM/EDV decreases with increasing age in both sexes but is not related to hypertension or obesity. Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Left ventricular myocardial performance assessed by 2-dimensional speckle tracking echocardiography in patients with sickle cell crisis.

PubMed

Sengupta, Shantanu P; Jaju, Rahul; Nugurwar, Abhijeet; Caracciolo, Giuseppe; Sengupta, Partho P

2012-01-01

The status of left ventricle in sickle cell anemia presenting in sickle crisis and follow up has been minimally studied in past. To determine the left ventricular (LV) myocardial performance in these patients, we performed the study to assess two dimensional strains imaging which allowed a rapid and an accurate analysis of global and regional LV myocardial performance in longitudinal, radial, and circumferential directions. In this prospective study, 2-dimensional echocardiography (2DE) images of the LV were obtained in 52 subjects which included 32 patients (23 ± 8yrs, 16 male) with homozygous sickle cell anemia (SCA) in sickle cell crisis and 20 healthy controls (23 ± 5 yrs, 11 male) using apical 4-chamber and parasternal short-axis at the basal, mid, and apical levels. Of these 32 patients, 2DE was performed again in 18 patients in follow up (8 months ± 5 days). Longitudinal, circumferential and radial strains (LS, CS and RS respectively) were quantified and compared in an 18-segment model using a novel speckle tracking system (2D Cardiac Performance Analysis, TomTec Imaging System, Munich, Germany). There was no significant difference in LV ejection fraction between both the groups (59.32 ± 12.6 vs. 52.3 ± 7.9; p-value > 0.05). In comparison with normal controls and follow up of sickle cell patients, peak LS was significantly attenuated in the subendocardial and subepicardial regions during sickle cell crisis (p < 0.05). However, a significant reduction in circumferential strain was evident only in subepicardial region (p < 0.001). Also patients in sickle cell crisis showed significantly higher radial strain parameters than controls (p < 0.001). Patients with SCA presenting in sickle cell crisis have reduced longitudinal shortening. LV myocardial performance remains unaltered due to relatively preserved circumferential shortening and increased radial thickening. Copyright © 2012 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

The effect of losartan and amlodipine on left ventricular diastolic function and atherosclerosis in Japanese patients with mild-to-moderate hypertension (J-ELAN) study.

PubMed

Yamamoto, Kazuhiro; Ozaki, Hitoshi; Takayasu, Ken; Akehi, Noriyuki; Fukui, Sugao; Sakai, Akihiko; Kodama, Mineo; Shimonagata, Tsuyoshi; Kobayashi, Keiji; Ota, Mitsushige; Horiguchi, Yasunori; Ebisuno, Shoji; Katsube, Yoshiki; Yamazaki, Tsutomu; Ohtsu, Hiroshi; Hori, Masatsugu

2011-03-01

This study was a prospective, randomized, open, blinded endpoint study to assess the effects of angiotensin II type 1 receptor blocker, losartan, compared with calcium channel blocker, amlodipine, on left ventricular (LV) diastolic function and atherosclerosis of the carotid artery in Japanese patients with mild-to-moderate hypertension, LV hypertrophy, diastolic dysfunction and preserved systolic function. Fifty-seven patients were randomly assigned to losartan- or amlodipine-based treatment groups and were followed up for 18 months. Blood pressure was similarly reduced by both regimens. Losartan shortened the transmitral E-wave deceleration time, and amlodipine reduced LV mass index; however, there was no significant difference in the percent changes of these indices between the two groups. Mean carotid intima-media thickness (mean IMT) as well as plaque score significantly increased in the amlodipine-based regimen (pre: 1.05±0.26 mm, follow-up: 1.23±0.33 mm, P=0.0015), but not in the losartan-based regimen (pre: 1.08±0.35 mm, follow-up: 1.16±0.52 mm, P=non-significant). The percent increase in mean IMT in the amlodipine-based regimen tended to be large compared with the losartan-based regimen (amlodipine: 19.8±23.7%, losartan: 6.9±23.3%, P=0.06). Under similar reduction of blood pressure, losartan is likely effective in protecting the progression of atherosclerosis of the carotid artery compared with amlodipine. Losartan may improve LV diastolic function, and amlodipine may attenuate LV hypertrophy; however, this study cannot make consecutive remarks about the superiority of either treatment regimen in the effects on cardiac function and geometry. This study has been registered at http://www.umin.ac.jp/ctr/listj/ (identifier C000000319). © 2011 The Japanese Society of Hypertension All rights reserved

Rationale and design of a multicentre, randomized, placebo-controlled trial of mirabegron, a Beta3-adrenergic receptor agonist on left ventricular mass and diastolic function in patients with structural heart disease Beta3-left ventricular hypertrophy (Beta3-LVH).

PubMed

Pouleur, Anne-Catherine; Anker, Stefan; Brito, Dulce; Brosteanu, Oana; Hasenclever, Dirk; Casadei, Barbara; Edelmann, Frank; Filippatos, Gerasimos; Gruson, Damien; Ikonomidis, Ignatios; Lhommel, Renaud; Mahmod, Masliza; Neubauer, Stefan; Persu, Alexandre; Gerber, Bernhard L; Piechnik, Stefan; Pieske, Burkert; Pieske-Kraigher, Elisabeth; Pinto, Fausto; Ponikowski, Piotr; Senni, Michele; Trochu, Jean-Noël; Van Overstraeten, Nancy; Wachter, Rolf; Balligand, Jean-Luc

2018-06-22

Progressive left ventricular (LV) remodelling with cardiac myocyte hypertrophy, myocardial fibrosis, and endothelial dysfunction plays a key role in the onset and progression of heart failure with preserved ejection fraction. The Beta3-LVH trial will test the hypothesis that the β 3 adrenergic receptor agonist mirabegron will improve LV hypertrophy and diastolic function in patients with hypertensive structural heart disease at high risk for developing heart failure with preserved ejection fraction. Beta3-LVH is a randomized, placebo-controlled, double-blind, two-armed, multicentre, European, parallel group study. A total of 296 patients will be randomly assigned to receive either mirabegron 50 mg daily or placebo over 12 months. The main inclusion criterion is the presence of LV hypertrophy, that is, increased LV mass index (LVMi) or increased wall thickening by echocardiography. The co-primary endpoints are a change in LVMi by cardiac magnetic resonance imaging and a change in LV diastolic function (assessed by the E/e' ratio). Secondary endpoints include mirabegron's effects on cardiac fibrosis, left atrial volume index, maximal exercise capacity, and laboratory markers. Two substudies will evaluate mirabegron's effect on endothelial function by pulse amplitude tonometry and brown fat activity by positron emission tomography using 17F-fluorodeoxyglucose. Morbidity and mortality as well as safety aspects will also be assessed. Beta3-LVH is the first large-scale clinical trial to evaluate the effects of mirabegron on LVMi and diastolic function in patients with LVH. Beta3-LVH will provide important information about the clinical course of this condition and may have significant impact on treatment strategies and future trials in these patients. © 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

Serum Bicarbonate and Structural and Functional Cardiac Abnormalities in Chronic Kidney Disease - A Report from the Chronic Renal Insufficiency Cohort Study.

PubMed

Dobre, Mirela; Roy, Jason; Tao, Kaixiang; Anderson, Amanda H; Bansal, Nisha; Chen, Jing; Deo, Rajat; Drawz, Paul; Feldman, Harold I; Hamm, L Lee; Hostetter, Thomas; Kusek, John W; Lora, Claudia; Ojo, Akinlolu O; Shrama, Kumar; Rahman, Mahboob

2016-01-01

Heart failure (HF) is a frequent occurrence in chronic kidney disease (CKD) patients and predicts poor survival. Serum bicarbonate is associated with increased rates of HF in CKD; however, the mechanisms leading to this association are incompletely understood. This study aims to assess whether serum bicarbonate is independently associated with structural and functional cardiac abnormalities in CKD. The association between serum bicarbonate and left ventricular (LV) hypertrophy (LVH), LV mass indexed to height2.7, LV geometry, ejection fraction (EF) and diastolic dysfunction was assessed in 3,483 participants without NYHA class III/IV HF, enrolled in the Chronic Renal Insufficiency Cohort study. The mean estimated glomerular filtration rate was 42.5 ± 17 ml/min/1.73 m2. The overall prevalence of LVH was 51.2%, with 57.8, 50.9 and 47.7% for bicarbonate categories <22, 22-26 and >26 mmol/l, respectively. Participants with low bicarbonate were more likely to have LVH and abnormal LV geometry (OR 1.32; 95% CI 1.07-1.64, and OR 1.57; 95% CI 1.14-2.16, respectively). However, the association was not statistically significant after adjustment for demographics, traditional cardiovascular risk factors, medications and kidney function (OR 1.07; 95% CI 0.66-1.72, and OR 1.27; 95% CI 0.64-2.51, respectively). No association was found between bicarbonate and systolic or diastolic dysfunction. During follow-up, no significant changes in LV mass or EF were observed in any bicarbonate strata. In a large CKD study, serum bicarbonate was associated with LV mass and concentric LVH; however, this association was attenuated after adjustment for clinical factors suggesting that the observed cardiac effects are mediated through yet unknown mechanisms. © 2016 Published by S. Karger AG, Basel.

A Mouse Model of Cardiomyopathy Induced by Mutations in the Hemochromatosis HFE Gene.

PubMed

Djemai, Haidar; Thomasson, Rémi; Trzaskus, Yvan; Mougenot, Nathalie; Meziani, Amira; Toussaint, Jean-François; Noirez, Philippe; Vitiello, Damien

2017-07-01

The heart is 1 of the organs most affected by hereditary hemochromatosis (HH). The clinical impact of cardiomyopathy in patients with HH requires a particular diagnosis and less invasive treatments. We developed a model of cardiomyopathy in knockout (KO) mice for the high-Fe (HFE) gene and assessed left ventricular (LV) function and structure from 7-20 months. Male wild-type (WT) heterozygous and KO SV129 mice for the HFE gene were used in this study. Twenty-four mice were used to assess LV function and structure by echocardiography at 7, 14, 18, and 20 months. Evaluations of LV function and structure and myocardial fibrosis were performed at 7 and 20 months. The percent decrease of LV thickness-to-radius ratio between 7 and 20 months was higher in KO mice compared with WT mice (-30.2% ± 5.3% vs -10.5% ± 4.9%; P < 0.01). The LV diameters were higher in old mice compared with young mice (+13% at end-diastole; +33% at end-systole; P < 0.001). The LV ejection fraction values were lower in KO mice compared with WT mice between 7 and 20 months. The highest difference was found at 14 months (60.0% ± 7.6% vs 78.1% ± 3.5%; P < 0.001). Myocardial fibrosis was higher in old KO mice compared with old WT mice (+55%; P < 0.001), and myocardial iron deposition was slightly increased in old KO mice compared with old WT mice (1.31% ± 0.33% vs 0.84% ± 0.22%; P = 0.056). The present mouse model has the potential to allow the determination of underlying mechanisms involved in the cardiomyopathy induced by HFE-related hemochromatosis. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Diagnostic and Prognostic Value of Long-Axis Strain and Myocardial Contraction Fraction Using Standard Cardiovascular MR Imaging in Patients with Nonischemic Dilated Cardiomyopathies.

PubMed

Arenja, Nisha; Riffel, Johannes H; Fritz, Thomas; André, Florian; Aus dem Siepen, Fabian; Mueller-Hennessen, Matthias; Giannitsis, Evangelos; Katus, Hugo A; Friedrich, Matthias G; Buss, Sebastian J

2017-06-01

Purpose To assess the utility of established functional markers versus two additional functional markers derived from standard cardiovascular magnetic resonance (MR) images for their incremental diagnostic and prognostic information in patients with nonischemic dilated cardiomyopathy (NIDCM). Materials and Methods Approval was obtained from the local ethics committee. MR images from 453 patients with NIDCM and 150 healthy control subjects were included between 2005 and 2013 and were analyzed retrospectively. Myocardial contraction fraction (MCF) was calculated by dividing left ventricular (LV) stroke volume by LV myocardial volume, and long-axis strain (LAS) was calculated from the distances between the epicardial border of the LV apex and the midpoint of a line connecting the origins of the mitral valve leaflets at end systole and end diastole. Receiver operating characteristic curve, Kaplan-Meier method, Cox regression, and classification and regression tree (CART) analyses were performed for diagnostic and prognostic performances. Results LAS (area under the receiver operating characteristic curve [AUC] = 0.93, P < .001) and MCF (AUC = 0.92, P < .001) can be used to discriminate patients with NIDCM from age- and sex-matched control subjects. A total of 97 patients reached the combined end point during a median follow-up of 4.8 years. In multivariate Cox regression analysis, only LV ejection fraction (EF) and LAS independently indicated the combined end point (hazard ratio = 2.8 and 1.9, respectively; P < .001 for both). In a risk stratification approach with classification and regression tree analysis, combined LV EF and LAS cutoff values were used to stratify patients into three risk groups (log-rank test, P < .001). Conclusion Cardiovascular MR-derived MCF and LAS serve as reliable diagnostic and prognostic markers in patients with NIDCM. LAS, as a marker for longitudinal contractile function, is an independent parameter for outcome and offers incremental information beyond LV EF and the presence of myocardial fibrosis. © RSNA, 2017 Online supplemental material is available for this article.

Spectrum and clinical significance of systolic function and myocardial fibrosis assessed by cardiovascular magnetic resonance in hypertrophic cardiomyopathy.

PubMed

Olivotto, Iacopo; Maron, Barry J; Appelbaum, Evan; Harrigan, Caitlin J; Salton, Carol; Gibson, C Michael; Udelson, James E; O'Donnell, Christopher; Lesser, John R; Manning, Warren J; Maron, Martin S

2010-07-15

In hypertrophic cardiomyopathy (HCM), the clinical significance attributable to the broad range of left ventricular (LV) systolic function, assessed as the ejection fraction (EF), is incompletely resolved. We evaluated the EF using cardiovascular magnetic resonance (CMR) imaging in a large cohort of patients with HCM with respect to the clinical status and evidence of left ventricular remodeling with late gadolinium enhancement (LGE). CMR imaging was performed in 310 consecutive patients, aged 42 +/- 17 years. The EF in patients with HCM was 71 +/- 10% (range 28% to 89%), exceeding that of 606 healthy controls without cardiovascular disease (66 +/- 5%, p <0.001). LGE reflecting LV remodeling showed an independent, inverse relation to the EF (B-0.69, 95% confidence interval -0.86 to -0.52; p <0.001) and was greatest in patients with an EF <50%, in whom it constituted a median value of 29% of the LV volume (interquartile range 16% to 40%). However, the substantial subgroup with low-normal EF values of 50% to 65% (n = 45; 15% of the whole cohort), who were mostly asymptomatic or mildly symptomatic (37 or 82% with New York Heart Association functional class I to II), showed substantial LGE (median 5% of LV volume, interquartile range 2% to 10%). This overlapped with the subgroup with systolic dysfunction and significantly exceeded that of patients with an EF of 66% to 75% and >75% (median 2% of the LV volume, interquartile range 1.5% to 4%; p <0.01). In conclusion, in a large cohort of patients with HCM, a subset of patients with low-normal EF values (50% to 65%) was identified by contrast-enhanced CMR imaging as having substantial degrees of LGE, suggesting a transition phase, potentially heralding advanced LV remodeling and systolic dysfunction, with implications for clinical surveillance and management. Copyright (c) 2010. Published by Elsevier Inc.

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics: a study utilizing deformation volume analysis

PubMed Central

Schneider, Caroline; Forsythe, Lynsey; Somauroo, John; George, Keith

2018-01-01

Background Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function; however, the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change. Methods A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume loops (deformation volume analysis – DVA). Results There was a leftward shift of the ε-volume loop from supine to 1 min and 5 min of HUT (P < 0.001). Moreover, longitudinal shortening was reduced (P < 0.001) with a concomitant increase in transverse thickening from supine to 1 min, which was further augmented at 5 min (P = 0.018). Conclusions Preload reduction occurs within 1 min of HUT but does not further reduce at 5 min. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations. PMID:29339401

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics: a study utilizing deformation volume analysis.

PubMed

Schneider, Caroline; Forsythe, Lynsey; Somauroo, John; George, Keith; Oxborough, David

2018-03-01

Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function; however, the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change. A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume loops (deformation volume analysis - DVA). There was a leftward shift of the ε-volume loop from supine to 1 min and 5 min of HUT ( P  < 0.001). Moreover, longitudinal shortening was reduced ( P  < 0.001) with a concomitant increase in transverse thickening from supine to 1 min, which was further augmented at 5 min ( P  = 0.018). Preload reduction occurs within 1 min of HUT but does not further reduce at 5 min. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations. © 2018 The authors.

Anabolic androgenic steroid use is associated with ventricular dysfunction on cardiac MRI in strength trained athletes.

PubMed

Luijkx, Tim; Velthuis, Birgitta K; Backx, Frank J G; Buckens, Constantinus F M; Prakken, Niek H J; Rienks, Rienk; Mali, Willem P Th M; Cramer, Maarten J

2013-08-10

Uncertainty remains about possible cardiac adaptation to resistance training. Androgenic anabolic steroids (AAS) use plays a potential role and may have adverse cardiovascular effects. To elucidate the effect of resistance training and of AAS-use on cardiac dimensions and function. Cardiac magnetic resonance (CMR) were performed in 156 male subjects aged 18-40 years: 52 non-athletes (maximum of 3 exercise hours/week), 52 strength-endurance (high dynamic-high static, HD-HS) athletes and 52 strength (low dynamic-high static, LD-HS) trained athletes (athletes ≥ 6 exercise hours/week). 28 LD-HS athletes denied and 24 admitted to AAS use for an average duration of 5 years (range 3 months-20 years). No significant differences were found between non-athletes and non-AAS-using LD-HS athletes. AAS-using LD-HS athletes had significantly larger LV and RV volumes and LV wall mass than non-AAS-using LD-HS athletes, but lower than HD-HS athletes. In comparison to all other groups AAS-using LD-HS athletes showed lower ejection fractions of both ventricles (LV/RV EF 51/48% versus 55-57/51-52%) and lower E/A ratios (LV/RV 1.5/1.2 versus 1.9-2.0/1.4-1.5) as an indirect measure of diastolic function. Linear regression models demonstrated a significant effect of AAS-use on LV EDV, LV EDM, systolic function and mitral valve E/A ratio (all ANOVA-tests p<0.05). Strength athletes who use AAS show significantly different cardiac dimensions and biventricular systolic dysfunction and impaired ventricular inflow as compared to non-athletes and non-AAS-using strength athletes. Increased ventricular volume and mass did not exceed that of strength-endurance athletes. These findings may help raise awareness of the consequences of AAS use. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Left ventricular remodeling and hypertrophy in patients with aortic stenosis: insights from cardiovascular magnetic resonance

PubMed Central

2012-01-01

Background Cardiovascular magnetic resonance (CMR) is the gold standard non-invasive method for determining left ventricular (LV) mass and volume but has not been used previously to characterise the LV remodeling response in aortic stenosis. We sought to investigate the degree and patterns of hypertrophy in aortic stenosis using CMR. Methods Patients with moderate or severe aortic stenosis, normal coronary arteries and no other significant valve lesions or cardiomyopathy were scanned by CMR with valve severity assessed by planimetry and velocity mapping. The extent and patterns of hypertrophy were investigated using measurements of the LV mass index, indexed LV volumes and the LV mass/volume ratio. Asymmetric forms of remodeling and hypertrophy were defined by a regional wall thickening ≥13 mm and >1.5-fold the thickness of the opposing myocardial segment. Results Ninety-one patients (61±21 years; 57 male) with aortic stenosis (aortic valve area 0.93±0.32cm2) were recruited. The severity of aortic stenosis was unrelated to the degree (r2=0.012, P=0.43) and pattern (P=0.22) of hypertrophy. By univariate analysis, only male sex demonstrated an association with LV mass index (P=0.02). Six patterns of LV adaption were observed: normal ventricular geometry (n=11), concentric remodeling (n=11), asymmetric remodeling (n=11), concentric hypertrophy (n=34), asymmetric hypertrophy (n=14) and LV decompensation (n=10). Asymmetric patterns displayed considerable overlap in appearances (wall thickness 17±2mm) with hypertrophic cardiomyopathy. Conclusions We have demonstrated that in patients with moderate and severe aortic stenosis, the pattern of LV adaption and degree of hypertrophy do not closely correlate with the severity of valve narrowing and that asymmetric patterns of wall thickening are common. Trial registration ClinicalTrials.gov Reference Number: NCT00930735 PMID:22839417

Treatment of Heart Failure With Associated Functional Mitral Regurgitation Using the ARTO System: Initial Results of the First-in-Human MAVERIC Trial (Mitral Valve Repair Clinical Trial).

PubMed

Rogers, Jason H; Thomas, Martyn; Morice, Marie-Claude; Narbute, Inga; Zabunova, Milana; Hovasse, Thomas; Poupineau, Mathieu; Rudzitis, Ainars; Kamzola, Ginta; Zvaigzne, Ligita; Greene, Samantha; Erglis, Andrejs

2015-07-01

MAVERIC (Mitral Valve Repair Clinical Trial) reports the safety and efficacy of the ARTO system in patients with symptomatic heart failure and functional mitral regurgitation (FMR). The ARTO system percutaneously modifies the mitral annulus to improve leaflet coaptation in FMR. The MAVERIC trial is a prospective, nonrandomized first-in-human study. Key inclusion criteria were systolic heart failure New York Heart Association functional classes II to IV, FMR grade ≥2+, left ventricular (LV) ejection fraction ≤40%, LV end-diastolic diameter >50 mm and ≤75 mm. Exclusion criteria were clinical variables that precluded feasibility of the ARTO procedure. Primary outcomes were safety (30-day major adverse events) and efficacy (MR reduction, LV volumes, and functional status). Eleven patients received the ARTO system, and there were no procedural adverse events. From baseline to 30 days, there were meaningful improvements. Effective regurgitant orifice area decreased from 30.3 ± 11.1 mm(2) to 13.5 ± 7.1 mm(2) and regurgitant volumes from 45.4 ± 15.0 ml to 19.5 ± 10.2 ml. LV end-systolic volume index improved from 77.5 ± 24.3 ml/m(2) to 68.5 ± 21.4 ml/m(2), and LV end-diastolic volume index 118.7 ± 28.6 ml/m(2) to 103.9 ± 21.2 ml/m(2). Mitral annular anteroposterior diameter decreased from 45.0 ± 3.3 mm to 38.7 ± 3.0 mm. Functional status was 81.8% New York Heart Association functional class III/IV improving to 54.6% functional class I/II. At 30 days, there were 2 adverse events: 1 pericardial effusion requiring surgical drainage; and 1 asymptomatic device dislodgement. The ARTO system is a novel transcatheter device that can be used safely with meaningful efficacy in the treatment of FMR. (Mitral Valve Repair Clinical Trial [MAVERIC]; NCT02302872). Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

An Integrin from Shrimp Litopenaeus vannamei Mediated Microbial Agglutination and Cell Proliferation

PubMed Central

Zhang, Ying; Wang, Leilei; Wang, Lingling; Wu, Ning; Zhou, Zhi; Song, Linsheng

2012-01-01

Background Integrins are a family of adhesion receptors which regulate cell proliferation, differentiation, leukocyte migration, and complement receptor-dependent phagocytosis. In invertebrates, as a cell adhesion receptor, β integrins play an important role for the balanced activation of immune defense responses especially during the encounter of infections. The present study attempts to characterize the immune functions of shrimp integrin (LvIntegrin) to have better understanding on the immune system and its regulation mechanisms in shrimps. Methodology A shrimp integrin was identified from the Pacific white shrimp Litopenaeus vannamei (designated as LvIntegrin). Its full-length cDNA was of 2621 bp with an open reading frame (ORF) of 2439 bp encoding a polypeptide of 812 amino acids. The mRNA expression of LvIntegrin was significantly up-regulated at 3, 6 and 12 h after Listonella anguillarum challenge. The cDNA fragment encoding β integrin domains (βA and hybrid domain) of LvIntegrin was recombined and expressed in Escherichia coli BL21(DE3)-pLysS. The recombinant protein (rLvIntegrin) could significantly agglutinate the tested microbe including E. coli JM109, L. anguillarum, Micrococcus luteus and Candida dattiladattila in the presence of divalent cations. Moreover, when NIH3T3 cells were cultured with rLvIntegrin, the proliferation rate increased significantly in a dose-dependent manner. Conclusions LvIntegrin, a shrimp β integrin was identified from L. vannamei, shared several highly conserved features. LvIntegrin exhibited broad-spectrum agglutination activity towards both bacteria and fungi and could improve the proliferation of NIH3T3 cells, indicating that LvIntegrin is involved in the immune response against microbe challenge and regulation of cell proliferation as a cell adhesion receptor in shrimp. PMID:22792387

An integrin from shrimp Litopenaeus vannamei mediated microbial agglutination and cell proliferation.

PubMed

Zhang, Ying; Wang, Leilei; Wang, Lingling; Wu, Ning; Zhou, Zhi; Song, Linsheng

2012-01-01

Integrins are a family of adhesion receptors which regulate cell proliferation, differentiation, leukocyte migration, and complement receptor-dependent phagocytosis. In invertebrates, as a cell adhesion receptor, β integrins play an important role for the balanced activation of immune defense responses especially during the encounter of infections. The present study attempts to characterize the immune functions of shrimp integrin (LvIntegrin) to have better understanding on the immune system and its regulation mechanisms in shrimps. A shrimp integrin was identified from the Pacific white shrimp Litopenaeus vannamei (designated as LvIntegrin). Its full-length cDNA was of 2621 bp with an open reading frame (ORF) of 2439 bp encoding a polypeptide of 812 amino acids. The mRNA expression of LvIntegrin was significantly up-regulated at 3, 6 and 12 h after Listonella anguillarum challenge. The cDNA fragment encoding β integrin domains (βA and hybrid domain) of LvIntegrin was recombined and expressed in Escherichia coli BL21(DE3)-pLysS. The recombinant protein (rLvIntegrin) could significantly agglutinate the tested microbe including E. coli JM109, L. anguillarum, Micrococcus luteus and Candida dattiladattila in the presence of divalent cations. Moreover, when NIH3T3 cells were cultured with rLvIntegrin, the proliferation rate increased significantly in a dose-dependent manner. LvIntegrin, a shrimp β integrin was identified from L. vannamei, shared several highly conserved features. LvIntegrin exhibited broad-spectrum agglutination activity towards both bacteria and fungi and could improve the proliferation of NIH3T3 cells, indicating that LvIntegrin is involved in the immune response against microbe challenge and regulation of cell proliferation as a cell adhesion receptor in shrimp.

Automatic Extraction of Myocardial Mass and Volume Using Parametric Images from Dynamic Nongated PET.

PubMed

Harms, Hendrik Johannes; Stubkjær Hansson, Nils Henrik; Tolbod, Lars Poulsen; Kim, Won Yong; Jakobsen, Steen; Bouchelouche, Kirsten; Wiggers, Henrik; Frøkiaer, Jørgen; Sörensen, Jens

2016-09-01

Dynamic cardiac PET is used to quantify molecular processes in vivo. However, measurements of left ventricular (LV) mass and volume require electrocardiogram-gated PET data. The aim of this study was to explore the feasibility of measuring LV geometry using nongated dynamic cardiac PET. Thirty-five patients with aortic-valve stenosis and 10 healthy controls underwent a 27-min (11)C-acetate PET/CT scan and cardiac MRI (CMR). The controls were scanned twice to assess repeatability. Parametric images of uptake rate K1 and the blood pool were generated from nongated dynamic data. Using software-based structure recognition, the LV wall was automatically segmented from K1 images to derive functional assessments of LV mass (mLV) and wall thickness. End-systolic and end-diastolic volumes were calculated using blood pool images and applied to obtain stroke volume and LV ejection fraction (LVEF). PET measurements were compared with CMR. High, linear correlations were found for LV mass (r = 0.95), end-systolic volume (r = 0.93), and end-diastolic volume (r = 0.90), and slightly lower correlations were found for stroke volume (r = 0.74), LVEF (r = 0.81), and thickness (r = 0.78). Bland-Altman analyses showed significant differences for mLV and thickness only and an overestimation for LVEF at lower values. Intra- and interobserver correlations were greater than 0.95 for all PET measurements. PET repeatability accuracy in the controls was comparable to CMR. LV mass and volume are accurately and automatically generated from dynamic (11)C-acetate PET without electrocardiogram gating. This method can be incorporated in a standard routine without any additional workload and can, in theory, be extended to other PET tracers. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Direct implantation versus platelet-rich fibrin-embedded adipose-derived mesenchymal stem cells in treating rat acute myocardial infarction.

PubMed

Sun, Cheuk-Kwan; Zhen, Yen-Yi; Leu, Steve; Tsai, Tzu-Hsien; Chang, Li-Teh; Sheu, Jiunn-Jye; Chen, Yung-Lung; Chua, Sarah; Chai, Han-Tan; Lu, Hung-I; Chang, Hsueh-Wen; Lee, Fan-Yen; Yip, Hon-Kan

2014-05-15

This study tested whether adipose-derived mesenchymal stem cells (ADMSC) embedded in platelet-rich fibrin (PRF) scaffold is superior to direct ADMSC implantation in improving left ventricular (LV) performance and reducing LV remodeling in a rat acute myocardial infarction (AMI) model of left anterior descending coronary artery (LAD) ligation. Twenty-eight male adult Sprague Dawley rats equally divided into group 1 [sham control], group 2 (AMI only), group 3 (AMI+direct ADMSC implantation), and group 4 (AMI+PRF-embedded autologous ADMSC) were sacrificed on day 42 after AMI. LV systolic and diastolic dimensions and volumes, and infarct/fibrotic areas were highest in group 2, lowest in group 1 and significantly higher in group 3 than in group 4, whereas LV performance and LV fractional shortening exhibited a reversed pattern (p<0.005). Protein expressions of inflammation (oxidative stress, IL-1β, MMP-9), apoptosis (mitochondrial Bax, cleaved PARP), fibrosis (Smad3, TGF-β), and pressure-overload biomarkers (BNP, MHC-β) displayed a pattern similar to that of LV dimensions, whereas anti-inflammatory (IL-10), anti-apoptotic (Bcl-2), and anti-fibrotic (Smad1/5, BMP-2) indices showed a pattern similar to that of LV performance among the four groups (all p<0.05). Angiogenesis biomarkers at protein (CXCR4, SDF-1α, VEGF), cellular (CD31+, CXCR4+, SDF-1α+), and immunohistochemical (small vessels) levels, and cardiac stem cell markers (C-kit+, Sca-1+) in infarct myocardium were highest in group 4, lowest in group 1, and significantly higher in group 3 than in group 2 (all p<0.005). PRF-embedded ADMSC is superior to direct ADMSC implantation in preserving LV function and attenuating LV remodeling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Regression of left ventricular hypertrophy and aortic remodelling in NO-deficient hypertensive rats: effect of L-arginine and spironolactone.

PubMed

Paulis, L; Matuskova, J; Adamcova, M; Pelouch, V; Simko, J; Krajcirovicova, K; Potacova, A; Hulin, I; Janega, P; Pechanova, O; Simko, F

2008-09-01

We investigated, whether the substrate for nitric oxide (NO) formation -L-arginine - and the aldosterone receptor antagonist - spironolactone - are able to reverse alterations of the left ventricle (LV) and aorta in N(omega)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension. Six groups of male adult Wistar rats were investigated: controls after 4 and 7 weeks of experiment, rats treated with L-NAME for 4 weeks and three recovery groups: spontaneous-reversion (4 weeks L-NAME + 3 weeks placebo), spironolactone-induced reversion (4 weeks L-NAME + 3 weeks spironolactone) and L-arginine-induced reversion (4 weeks L-NAME+ 3 weeks L-arginine). Blood pressure was measured by tail-cuff plethysmography. Relative weight of the LV, myocardial fibrosis (based upon histomorphometry and hydroxyproline determination) and conjugated dienes in the LV and aortic cross-sectional area, inner diameter and wall thickness were determined. NO-synthase activity was investigated in the LV and aorta. L-NAME administration induced hypertension, left ventricular hypertrophy (LVH), LV fibrosis, aortic thickening and diminution of NO-synthase activity in the LV and aorta. Reduction in blood pressure and regression of LVH were observed in all recovery groups, yet reduction in LV fibrosis and aortic thickening were not. NO-synthase activity was restored only in the L-arginine and spironolactone group. In our study, the reversion of hypertension and LVH was not dependent on the restoration of NO-synthase activity. Moreover, LV fibrosis and aortic remodelling seem to be more resistant to conditions resulting in regression of LVH. Preserved level of fibrosis in the initial period of LVH regression might result in loss of structural homogeneity and possible functional alterations of the LV.

Organization and cellular arrangement of two neurogenic regions in the adult ferret (Mustela putorius furo) brain.

PubMed

Takamori, Yasuharu; Wakabayashi, Taketoshi; Mori, Tetsuji; Kosaka, Jun; Yamada, Hisao

2014-06-01

In the adult mammalian brain, two neurogenic regions have been characterized, the subventricular zone (SVZ) of the lateral ventricle (LV) and the subgranular zone (SGZ) of the dentate gyrus (DG). Despite remarkable knowledge of rodents, the detailed arrangement of neurogenic regions in most mammals is poorly understood. In this study, we used immunohistochemistry and cell type-specific antibodies to investigate the organization of two germinal regions in the adult ferret, which belongs to the order Carnivora and is widely used as a model animal with a gyrencephalic brain. From the SVZ to the olfactory bulb, doublecortin-positive cells tended to organize in chain-like clusters, which are surrounded by a meshwork of astrocytes. This structure is homologous to the rostral migratory stream (RMS) described in other species. Different from rodents, the horizontal limb of the RMS emerges directly from the LV, and the anterior region of the LV extends rostrally and reached the olfactory bulb. In the DG, glial fibrillary acidic protein-positive cells with long radial processes as well as doublecortin-positive cells are oriented in the SGZ. In both regions, doublecortin-positive cells showed characteristic morphology and were positive for polysialylated-neural cell adhesion molecule, beta-III tubulin, and lamin B1 (intense staining). Proliferating cells were detected in both regions using antibodies against proliferating cell nuclear antigen and phospho-histone H3. These observations demonstrate that the two neurogenic regions in ferrets have a similar cellular composition as those of other mammalian species despite anatomical differences in the brain. Copyright © 2013 Wiley Periodicals, Inc.

Acceleration rate of mitral inflow E wave: a novel transmitral doppler index for assessing diastolic function.

PubMed

Badkoubeh, Roya Sattarzadeh; Tavoosi, Anahita; Jabbari, Mostafa; Parsa, Amir Farhang Zand; Geraeli, Babak; Saadat, Mohammad; Larti, Farnoosh; Meysamie, Ali Pasha; Salehi, Mehrdad

2016-06-10

We performed comprehensive transmitral and pulmonary venous Doppler echocardiographic studies to devise a novel index of diastolic function. This is the first study to assess the utility of the acceleration rate (AR) of the E wave of mitral inflow as a primary diagnostic modality for assessing diastolic function. Study group consisted of 84 patients (53 + 11 years) with left ventricle (LV) diastolic dysfunction and 34 healthy people (35 ± 9 years) as control group, who were referred for clinically indicated two-dimensional transthoracic echocardiogram (TTE) during 2012 and 2013 to Imam Hospital. Normal controls were defined as patients without clinical evidence of cardiac disease and had normal TTE. LV diastolic function was determined according to standardized protocol of American Society of Echocardiography (ASE). As our new parameter, AR of E wave of mitral inflow was also measured in all patients. It was represented by the slope of the line between onset of E wave and peak of it. Correlation between AR of E wave and LV diastolic function grade was measured using the Spearman correlation coefficient. Receiver operating characteristic (ROC) curve was used to determine the sensitivity and specificity of AR of E wave in diagnosing LV diastolic dysfunction in randomly selected two-thirds of population then its derived cutoff was evaluated in rest of the population. The institutional review board of the hospital approved the study protocol. All participants gave written informed consent. This investigation was in accordance with the Declaration of Helsinki. The mean value of AR was 1010 ± 420 cm/s(2) in patients whereas the mean value for the normal controls was 701 ± 210 cm/s(2). There was a strong and graded relation between AR of E wave of mitral inflow and LV diastolic function grade (Spearman P ≤0.0001, rs =0.69). ROC curve analysis revealed that AR of E wave of mitral inflow =750 cm/s(2) predicted moderate or severe LV diastolic dysfunction with 89 % sensitivity and 89 % specificity (area under curve [AUC] = 0.903, P <0.0001). Application of this cutoff on test group showed 96 % sensitivity and 77 % specificity with AUC = 0.932 and P <0.0001. AR of E wave of mitral inflow could be used for assessment of diastolic function, especially moderate or severe diastolic dysfunction. However, before its clinical application, external validation should be considered.

[The prognostic value of cardio-pulmonary exercise test parameters in patients with asymptomatic ischemic heart dysfunction during 2-years observation].

PubMed

Skrzypek, Agnieszka; Nessler, Jadwiga

2015-01-01

Measurement of oxygen uptake at the maximal exercise (VO2max) in the cardio-pulmonary exercise test provides the most reliable information about exertion tolerance. Establishment of VO2peak, VE/CO2 and AT value in the early diagnosis of asymptomatic heart dysfunction in patients with coronary disease (CAD) and prognosis during 2-years observation. The study population: 57 patients (35 M) with CAD, without any signs or symptoms of heart dysfunction, without any features of myocardial infarction, in the age 51.08 +/- 4.01. The analysis was performed twice: in the beginning and after 2-years observation. Physical examinations, echocardiographic parameters [(assessment of systolic and diastolic dysfunction of the left ventricle (LV)] and spiroergometric parameters (VO2peak, VE/CO2 at AT). On the basis of echocardiographic examination, there were created groups of patients: Group A--the patients with normal LV function (n=32; 56.2%; 23 M); Group B--the patients with diastolic heart dysfunction (n=22; 38.6%; 10 M); Group A--32 patients in the age of 50.9 +/- 4, 23 men. Values of VO2pe ak :28.8 +/- 6 ml/kg/min, VE/CO2 28.8 +/- 4.9 and AT 18 +/- 2.5. Group B--the patients with diastolic heart dysfunction: 22 (39%) patients; 10 men, in the age of 51.2 +/- 4.3. Values of VO2peak: 26 +/- 3.4 mi/ kg/min, VE/CO2 31.2 +/- 5.1 and AT 16 +/- 2.5. In the beginning of the study was established significantly differences between anaerobic threshold and degree of heart dysfunction (p=0.039). (1) There was observed that VO2 A and VE/CO2 depended on filling LV profile LV and also of systolic LV function. Anaerobic threshold significantly depended on LV filling pattern. (2) In asymptomatic patients with LV diastolic dysfunction and VO2peak < or = 18.4 ml/kg/min was observed progression of LV diastolic dysfunction during two years.

Usefulness of speckle tracking echocardiography in hypertensive crisis and the effect of medical treatment.

PubMed

Alam, Mahboob; Zhang, Lily; Stampehl, Mark; Lakkis, Nasser; Dokainish, Hisham

2013-07-15

The acute impact of hypertensive crisis, and changes after treatment, on left ventricular (LV) systolic and diastolic function using comprehensive echocardiography, including speckle tracking, has not been well characterized. Thirty consecutive patients admitted to the hospital from the emergency room with hypertensive crisis underwent Doppler echocardiography at baseline and after blood pressure optimization. The mean age of the patients was 54 ± 13 years, with 19 men (63%). The most common presenting symptoms included dyspnea (70%), chest pain (43%), and altered mental status (13%). Mean systolic and diastolic blood pressures at presentation were 198 ± 12 and 122 ± 12 mm Hg, decreasing to 143 ± 15 and 77 ± 12 mm Hg (p <0.001 for both) after treatment. There was no significant change in LV ejection fraction between baseline and follow-up (48 ± 18% vs 46 ± 18%, p = 0.50); however, global longitudinal LV systolic strain (-10 ± 4% to -12 ± 4%, p = 0.01) and global systolic strain rate (-1.0 ± 0.4 vs -1.4 ± 0.6 s(-1), p = 0.01) significantly improved. Mean global early diastolic strain (-7.2 ± 4.0% to -9.4 ± 2.9%, p = 0.004) and early diastolic strain rate (0.3 ± 0.2 to 0.5 ± 0.4 s(-1), p = 0.05) also improved after treatment. On multivariate analysis, the independent predictors of LV longitudinal strain at follow-up were LV ejection fraction (p <0.001), heart rate (p = 0.005), systolic blood pressure (p = 0.04), and left atrial volume index (p = 0.05). In conclusion, as opposed to LV ejection fraction, LV systolic strain and strain rate were depressed during hypertensive crisis and significantly improved after medical treatment. LV diastolic function, assessed using conventional and speckle-tracking parameters, was also depressed and significantly improved after treatment. Copyright © 2013 Elsevier Inc. All rights reserved.

Right ventricular failure resulting from pressure overload: role of intra-aortic balloon counterpulsation and vasopressor therapy.

PubMed

Liakopoulos, Oliver J; Ho, Jonathan K; Yezbick, Aaron B; Sanchez, Elizabeth; Singh, Vivek; Mahajan, Aman

2010-11-01

Augmentation of coronary perfusion may improve right ventricular (RV) failure following acute increases of RV afterload. We investigated whether intra-aortic balloon counterpulsation (IABP) can improve cardiac function by enhancing myocardial perfusion and reversing compromised biventricular interactions using a model of acute pressure overload. In 10 anesthetized pigs, RV failure was induced by pulmonary artery constriction and systemic hypertension strategies with IABP, phenylephrine (PE), or the combination of both were tested. Systemic and ventricular hemodynamics [cardiac index(CI), ventricular pressures, coronary driving pressures (CDP)] were measured and echocardiography was used to assess tricuspid valve regurgitation, septal positioning (eccentricity index (ECI)), and changes in ventricular and septal dimensions and function [myocardial performance index (MPI), peak longitudinal strain]. Pulmonary artery constriction resulted in doubling of RV systolic pressure (54 ± 4mm Hg), RV distension, severe TR (4+) with decreased RV function (strain: -33%; MPI: +56%), septal flattening (Wt%: -35%) and leftward septal shift (ECI:1.36), resulting in global hemodynamic deterioration (CI: -51%; SvO(2): -26%), and impaired CDP (-30%; P<0.05). IABP support alone failed to improve RV function despite higher CDP (+33%; P<0.05). Systemic hypertension by PE improved CDP (+70%), RV function (strain: +22%; MPI: -21%), septal positioning (ECI:1.12) and minimized TR, but LV dysfunction (strain: -25%; MPI: +31%) occurred after LV afterloading (P<0.05). With IABP, less PE (-41%) was needed to maintain hypertension and CDP was further augmented (+25%). IABP resulted in LV unloading and restored LV function, and increased CI (+46%) and SvO(2) (+29%; P<0.05). IABP with minimal vasopressors augments myocardial perfusion pressure and optimizes RV function after pressure-induced failure. Copyright © 2010 Elsevier Inc. All rights reserved.

Training-specific changes in cardiac structure and function: a prospective and longitudinal assessment of competitive athletes.

PubMed

Baggish, Aaron L; Wang, Francis; Weiner, Rory B; Elinoff, Jason M; Tournoux, Francois; Boland, Arthur; Picard, Michael H; Hutter, Adolph M; Wood, Malissa J

2008-04-01

This prospective, longitudinal study examined the effects of participation in team-based exercise training on cardiac structure and function. Competitive endurance athletes (EA, n = 40) and strength athletes (SA, n = 24) were studied with echocardiography at baseline and after 90 days of team training. Left ventricular (LV) mass increased by 11% in EA (116 +/- 18 vs. 130 +/- 19 g/m(2); P < 0.001) and by 12% in SA (115 +/- 14 vs. 132 +/- 11 g/m(2); P < 0.001; P value for the compared Delta = NS). EA experienced LV dilation (end-diastolic volume: 66.6 +/- 10.0 vs. 74.7 +/- 9.8 ml/m(2), Delta = 8.0 +/- 4.2 ml/m(2); P < 0.001), enhanced diastolic function (lateral E': 10.9 +/- 0.8 vs. 12.4 +/- 0.9 cm/s, P < 0.001), and biatrial enlargement, while SA experience LV hypertrophy (posterior wall: 4.5 +/- 0.5 vs. 5.2 +/- 0.5 mm/m(2), P < 0.001) and diminished diastolic function (E' basal lateral LV: 11.6 +/- 1.3 vs. 10.2 +/- 1.4 cm/s, P < 0.001). Further, EA experienced right ventricular (RV) dilation (end-diastolic area: 1,460 +/- 220 vs. 1,650 +/- 200 mm/m(2), P < 0.001) coupled with enhanced systolic and diastolic function (E' basal RV: 10.3 +/- 1.5 vs. 11.4 +/- 1.7 cm/s, P < 0.001), while SA had no change in RV parameters. We conclude that participation in 90 days of competitive athletics produces significant training-specific changes in cardiac structure and function. EA develop biventricular dilation with enhanced diastolic function, while SA develop isolated, concentric left ventricular hypertrophy with diminished diastolic relaxation.

Phonological short-term memory in logopenic variant primary progressive aphasia and mild Alzheimer's disease.

PubMed

Meyer, Aaron M; Snider, Sarah F; Campbell, Rachael E; Friedman, Rhonda B

2015-10-01

It has been argued that individuals with logopenic variant primary progressive aphasia (lvPPA) have an impairment of the phonological loop, which is a component of the short-term memory (STM) system. In contrast, this type of impairment is not thought to be present in mild typical Alzheimer's disease (AD). Thus, one would predict that people with lvPPA would score significantly lower than a matched AD group on tasks that require phonological STM. In the current study, an lvPPA group was compared with a mild AD group that was matched on age, education, and general cognitive functioning. For a subset of the tasks that involved pseudowords, the AD and lvPPA groups were compared to a healthy control group that was matched on age and education. The lvPPA group was more impaired than the AD group on all of the tasks that required phonological STM, including the pseudoword tasks, but there were no significant differences between these groups on tasks that required visuospatial STM. Compared to the healthy controls, the lvPPA group performed significantly worse on the repetition and reading of pseudowords, while the AD group did not differ significantly from the controls on these tasks. These findings are consistent with the hypothesis that phonological STM is impaired in lvPPA. Copyright © 2015 Elsevier Ltd. All rights reserved.

Automatic localization of the left ventricular blood pool centroid in short axis cardiac cine MR images.

PubMed

Tan, Li Kuo; Liew, Yih Miin; Lim, Einly; Abdul Aziz, Yang Faridah; Chee, Kok Han; McLaughlin, Robert A

2018-06-01

In this paper, we develop and validate an open source, fully automatic algorithm to localize the left ventricular (LV) blood pool centroid in short axis cardiac cine MR images, enabling follow-on automated LV segmentation algorithms. The algorithm comprises four steps: (i) quantify motion to determine an initial region of interest surrounding the heart, (ii) identify potential 2D objects of interest using an intensity-based segmentation, (iii) assess contraction/expansion, circularity, and proximity to lung tissue to score all objects of interest in terms of their likelihood of constituting part of the LV, and (iv) aggregate the objects into connected groups and construct the final LV blood pool volume and centroid. This algorithm was tested against 1140 datasets from the Kaggle Second Annual Data Science Bowl, as well as 45 datasets from the STACOM 2009 Cardiac MR Left Ventricle Segmentation Challenge. Correct LV localization was confirmed in 97.3% of the datasets. The mean absolute error between the gold standard and localization centroids was 2.8 to 4.7 mm, or 12 to 22% of the average endocardial radius. Graphical abstract Fully automated localization of the left ventricular blood pool in short axis cardiac cine MR images.

Role of Doppler Diastolic Parameters in Differentiating Physiological Left Ventricular Hypertrophy from Hypertrophic Cardiomyopathy.

PubMed

Finocchiaro, Gherardo; Dhutia, Harshil; D'Silva, Andrew; Malhotra, Aneil; Sheikh, Nabeel; Narain, Rajay; Ensam, Bode; Papatheodorou, Stathis; Tome, Maite; Sharma, Rajan; Papadakis, Michael; Sharma, Sanjay

2018-05-01

The association between athletic participation and alteration in diastolic function is not well established. The aims of this study were to determine the spectrum of Doppler parameters of left ventricular (LV) diastolic function in a large cohort of healthy athletes and to quantify the overlap between physiologic LV hypertrophy and hypertrophic cardiomyopathy (HCM). A retrospective analysis of indices of LV diastolic function was performed in 1,510 healthy athletes (mean age, 22 ± 5 years; range, 13-33 years; 72% men). The results were compared with those from 58 young patients with HCM. Septal E' < 7 cm/sec and lateral E' < 10 cm/sec were found in five (0.3%) and eight (0.5%) athletes, respectively. Septal E' was >14.6 cm/sec in 170 (11%) and lateral E' was >19.9 cm/sec in 430 (28%) athletes. Athletes aged >25 years showed lower E' velocities compared with younger athletes (mean septal E', 11.8 ± 6.1 vs 12.9 ± 5.9 cm/sec [P < .001]; mean lateral E', 17.1 ± 3.6 vs 19.3 ± 4.1 cm/sec [P < .001]). Athletes with high indexed LV end-diastolic diameters (>32 mm/m 2 ) exhibited lower septal E' compared with athletes with normal indexed LV end-diastolic diameters (mean septal E', 11.9 ± 6 vs 12.7 ± 6 cm/sec; P = .002). Septal E' < 10 cm/sec and lateral E' < 12 cm/sec showed the best accuracy in differentiating between HCM and athlete's heart. Reduced septal and lateral E' are rarely observed in young elite athletes. Tissue Doppler velocities tend to decrease with increasing age and LV size, and values representative of supernormal diastolic function are found in less than one-third of young athletes. Cutoff thresholds for Doppler parameters of diastolic function should be corrected for multiple demographic and clinical variables to differentiate cardiac adaptation to exercise from HCM in young individuals. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

What is the association between left ventricular diastolic dysfunction and 6-minute walk test in hypertensive patients?

PubMed

Farag, El-Sayed M; Al-Daydamony, Mohammad M; Gad, Marwa M

2017-03-01

Heart failure (HF) is a major health problem. Hypertension is an important cause of HF. Most hypertensive patients have some degree of left ventricular (LV) diastolic dysfunction. The 6-minute walk test (6MWT) provides objective data about the exercise tolerance. We aimed to find the association between the degree of LV diastolic dysfunction and the functional capacity assessed by 6MWT in hypertensive patients. The study included 200 asymptomatic hypertensive patients. All patients had undergone full history taking, complete clinical examination, electrocardiography, echocardiography for assessment of LV dimensions, systolic and diastolic dysfunction, and 6MWT. Patients were classified into two groups according to the presence or absence of LV diastolic dysfunction. Clinical and echocardiographic data were comparable between the two groups. Regarding 6MWT, at the end of the test, patients with diastolic dysfunction had significantly higher systolic (P = .0088) and diastolic (P = .019) blood pressure and higher Borg score for dyspnea (P < .00001). The distant walked and percentage of the distance to predicted value were significantly lower in patients with diastolic dysfunction (P = .0322 and .0002, respectively). Incidence of abnormal 6MWT was significantly higher in patients with diastolic dysfunction (P = .00041). Compared to patients with grades I and II, patients with grade III diastolic dysfunction had significantly higher Borg score (P = .013), lower distance walked (P = .039), and lower percentage of distance to predicted vale (P = .009). Independent predictors for abnormal 6MWT were as follows: E/E' ≥15 (P = .0022), E'/A' <1 (P = .0081), and deceleration time of E-wave <160 (P = .013). The presence of LV diastolic dysfunction in hypertensive patients has a bad effect on 6MWT. The degree of LV diastolic dysfunction was correlated with 6MWT results. It may be important to investigate LV diastolic function in asymptomatic hypertensive patients. Copyright © 2017 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Impact of percutaneous mitral valvuloplasty on left ventricular function in patients with mitral stenosis assessed by 3D echocardiography.

PubMed

Esteves, William Antonio M; Lodi-Junqueira, Lucas; Soares, Juliana Rodrigues; Sant'Anna Athayde, Guilherme Rafael; Goebel, Gabriela Assunção; Carvalho, Lucas Amorim; Zeng, Xin; Hung, Judy; Tan, Timothy C; Nunes, Maria Carmo Pereira

2017-12-01

The status of intrinsic left ventricular (LV) contractility in patients with isolated rheumatic mitral stenosis (MS) has been debated. The acute changes in loading conditions after percutaneous mitral valvuloplasty (PMV) may affect LV performance. We aimed to examine the acute effects of PMV on LV function and identify factors associated with LV ejection fraction (LVEF) changes, and determinants of long-term events following the procedure. One hundred and forty-two patients who underwent PMV for symptomatic rheumatic MS (valve area of 0.99±0.3cm 2 ) were prospectively enrolled. LV volumes and LVEF were measured by three-dimensional (3D) echocardiography. Long-term outcome was a composite endpoint of death, mitral valve (MV) replacement, repeat PMV, new onset of atrial fibrillation, and stroke. The mean age was 42.3±12.1years, and 125 patients were women (88%). After PMV, LVEF increased significantly (51.4 vs 56.5%, p<0.001), primary due to a significant increase in LV end-diastolic volume (65.8mL vs 67.9mL, p=0.002), and resultant increase in the stroke volume (33.9mL vs 39.6mL, p<0.001). Changes in cardiac index and systolic pulmonary artery pressure were associated with LVEF changes after PMV. During a mean follow-up period of 30.8months, 28 adverse clinical events were observed. Postprocedural mitral regurgitation, MV area, and mean gradient were independent predictors of composite endpoints. In patients with rheumatic MS, PMV resulted in a significant improvement in LV end-diastolic volume, stroke volume and consequently increased in LVEF. Changes in cardiac index and systolic pulmonary artery pressure were associated with LVEF changes after PMV. The predictors of long-term adverse events following PMV were post-procedural variables, including mitral regurgitation, valve area, and mean gradient. Copyright © 2017 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Feng; Zhang, Yuanyuan; Wang, Qingzhu

Objective: This study was designed to investigate the protective effect of forkhead transcription factor O1 (FoxO1) on podocyte injury in rats with diabetic nephropathy. Methods: Streptozotocin-induced diabetic rats were served as DM group, while DM rats transfected with blank lentiviral vectors (LV-pSC-GFP) or lentiviral vectors carrying constitutively active FoxO1 (LV-CA-FoxO1) were served as LV-NC group or LV-CA group, respectively. The control group (NG) consisted of uninduced rats that received an injection of diluent buffer. At 2, 4, and 8 weeks after transfection, the levels of urine albumin, blood glucose, blood urea nitrogen, serum creatinine and urine podocalyxin were measured. Real-timemore » PCR and western blotting were performed to measure mRNA and protein levels of FoxO1, podocalyxin, nephrin, and desmin in renal cortex. In addition, light and electron microscopy were used to detect structural changes in the glomerulus and podocytes. Results: Compared with the rats in LV-NC and DM groups, LV-CA rats showed a significant increase in FoxO1 mRNA and protein levels and a distinct decrease in urine albumin, blood urea nitrogen, and serum creatinine (except at the two-week time point) levels (p < 0.05). Podocalyxin and nephrin mRNA and protein levels increased (p < 0.05), whereas desmin mRNA and protein levels decreased (p < 0.05). Pathological changes in glomerulus were also ameliorated in LV-CA group. Conclusions: Upregulating expression of FoxO1 by transduction with recombinant lentivirus ameliorates podocyte injury in diabetic rats. - Highlights: • The structures and functions of podocytes were impaired in STZ-induced diabetic rats. • Constitutively active FoxO1 ameliorates structure injury and preserves function of podocytes in diabetic rats. • FoxO1 may alleviate the pathological changes associated with diabetic nephropathy.« less

Myelodysplastic syndromes and acute myeloid leukemia in cats infected with feline leukemia virus clone33 containing a unique long terminal repeat.

PubMed

Hisasue, Masaharu; Nagashima, Naho; Nishigaki, Kazuo; Fukuzawa, Isao; Ura, Shigeyoshi; Katae, Hiromi; Tsuchiya, Ryo; Yamada, Takatsugu; Hasegawa, Atsuhiko; Tsujimoto, Hajime

2009-03-01

Feline leukemia virus (FeLV) clone33 was obtained from a domestic cat with acute myeloid leukemia (AML). The long terminal repeat (LTR) of this virus, like the LTRs present in FeLV from other cats with AML, differs from the LTRs of other known FeLV in that it has 3 tandem direct 47-bp repeats in the upstream region of the enhancer (URE). Here, we injected cats with FeLV clone33 and found 41% developed myelodysplastic syndromes (MDS) characterized by peripheral blood cytopenias and dysplastic changes in the bone marrow. Some of the cats with MDS eventually developed AML. The bone marrow of the majority of cats with FeLV clone33 induced MDS produced fewer erythroid and myeloid colonies upon being cultured with erythropoietin or granulocyte-macrophage colony-stimulating factor (GM-SCF) than bone marrow from normal control cats. Furthermore, the bone marrow of some of the cats expressed high-levels of the apoptosis-related genes TNF-alpha and survivin. Analysis of the proviral sequences obtained from 13 cats with naturally occurring MDS reveal they also bear the characteristic URE repeats seen in the LTR of FeLV clone33 and other proviruses from cats with AML. Deletions and mutations within the enhancer elements are frequently observed in naturally occurring MDS as well as AML. These results suggest that FeLV variants that bear URE repeats in their LTR strongly associate with the induction of both MDS and AML in cats.

Targeted Imaging of the Spatial and Temporal Variation of Matrix Metalloproteinase Activity in Porcine Model of Post-Infarct Remodeling: Relationship to Myocardial Dysfunction

PubMed Central

Sahul, Zakir H.; Mukherjee, Rupak; Song, James; McAteer, Jarod; Stroud, Robert E.; Dione, Donald P.; Staib, Lawrence; Papademetris, Xenophon; Dobrucki, Lawrence W.; Duncan, James S.; Spinale, Francis G.; Sinusas, Albert J.

2011-01-01

Background Matrix metalloproteinases (MMPs) are known to modulate left ventricular (LV) remodeling after a myocardial infarction (MI). However, the temporal and spatial variation of MMP activation and their relationship to mechanical dysfunction post MI remains undefined. Methods and Results MI was surgically induced in pigs (n=23) and cine MR and dual isotope hybrid SPECT/CT imaging obtained using thallium-201 (201Tl) and a technetium-99m labeled MMP targeted tracer (99mTc-RP805) at 1, 2 and 4 weeks post MI along with controls (n=5). Regional myocardial strain was computed from MR images and related to MMP zymography and ex vivo myocardial 99mTc-RP805 retention. MMP activation as assessed by in vivo and ex vivo 99mTc-RP805 imaging/retention studies was increased nearly 5-fold within the infarct region at 1 week post-MI and remained elevated up to 1 month post-MI. The post-MI change in LV end-diastolic volumes was correlated with MMP activity (y=31.34e0.48x, p=0.04). MMP activity was increased within the border and remote regions early post-MI, but declined over 1 month. There was a high concordance between regional 99mTc-RP805 uptake and ex vivo MMP-2 activity. Conclusions A novel, multimodality non-invasive hybrid SPECT/CT imaging approach was validated and applied for in vivo evaluation of MMP activation in combination with cine MR analysis of LV deformation. Increased 99mTc-RP805 retention was seen throughout the heart early post-MI and was not purely a reciprocal of 201Tl perfusion. 99mTc-RP805 SPECT/CT imaging may provide unique information regarding regional myocardial MMP activation and predict late post-MI LV remodeling. PMID:21505092

The influence of adrenergic stimulation on sex differences in left ventricular twist mechanics.

PubMed

Williams, Alexandra M; Shave, Rob E; Cheyne, William S; Eves, Neil D

2017-06-15

Sex differences in left ventricular (LV) mechanics occur during acute physiological challenges; however, it is unknown whether sex differences in LV mechanics are fundamentally regulated by differences in adrenergic control. Using two-dimensional echocardiography and speckle tracking analysis, this study compared LV mechanics in males and females matched for LV length during post-exercise ischaemia (PEI) and β 1 -adrenergic receptor blockade. Our data demonstrate that while basal rotation was increased in males, LV twist was not significantly different between the sexes during PEI. In contrast, during β 1 -adrenergic receptor blockade, LV apical rotation, twist and untwisting velocity were reduced in males compared to females. Significant relationships were observed between LV twist and LV internal diameter and sphericity index in females, but not males. These findings suggest that LV twist mechanics may be more sensitive to alterations in adrenergic stimulation in males, but more highly influenced by ventricular structure and geometry in females. Sex differences in left ventricular (LV) mechanics exist at rest and during acute physiological stress. Differences in cardiac autonomic and adrenergic control may contribute to sex differences in LV mechanics and LV haemodynamics. Accordingly, this study aimed to investigate sex differences in LV mechanics with altered adrenergic stimulation achieved through post-handgrip-exercise ischaemia (PEI) and β 1 -adrenergic receptor (AR) blockade. Twenty males (23 ± 5 years) and 20 females (22 ± 3 years) were specifically matched for LV length (males: 8.5 ± 0.5 cm, females: 8.2 ± 0.6 cm, P = 0.163), and two-dimensional speckle-tracking echocardiography was used to assess LV structure and function at baseline, during PEI and following administration of 5 mg bisoprolol (β 1 -AR antagonist). During PEI, LV end-diastolic volume and stroke volume were increased in both groups (P < 0.001), as was end-systolic wall stress (P < 0.001). LV twist and apical rotation were not altered from baseline or different between the sexes; however, basal rotation increased in males (P = 0.035). During β 1 -AR blockade, LV volumes were unchanged but blood pressure and heart rate were reduced in both groups (P < 0.001). LV apical rotation (P = 0.036) and twist (P = 0.029) were reduced in males with β 1 -AR blockade but not females, resulting in lower apical rotation (males: 6.8 ± 2.1 deg, females: 8.8 ± 2.3 deg, P = 0.007) and twist (males: 8.6 ± 1.9 deg, females: 10.7 ± 2.8 deg, P = 0.008), and slower untwisting velocity (males: 68.2 ± 22.1 deg s -1 , females: 82.0 ± 18.7 deg s -1 , P = 0.046) compared to females. LV twist mechanics are reduced in males compared to females during reductions to adrenergic stimulation, providing preliminary evidence that LV twist mechanics may be more sensitive to adrenergic control in males than in females. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

Gene transfer as a strategy to achieve permanent cardioprotection II: rAAV-mediated gene therapy with heme oxygenase-1 limits infarct size 1 year later without adverse functional consequences.

PubMed

Li, Qianhong; Guo, Yiru; Ou, Qinghui; Wu, Wen-Jian; Chen, Ning; Zhu, Xiaoping; Tan, Wei; Yuan, Fangping; Dawn, Buddhadeb; Luo, Li; Hunt, Gregory N; Bolli, Roberto

2011-11-01

Extensive evidence indicates that heme oxygenase-1 (HO-1) exerts potent cytoprotective effects in response to stress. Previous studies have shown that gene therapy with HO-1 protects against myocardial ischemia/reperfusion injury for up to 8 weeks after gene transfer. However, the long-term effects of HO-1 gene therapy on myocardial ischemic injury and function are unknown. To address this issue, we created a recombinant adeno-associated viral vector carrying the HO-1 gene (rAAV/HO-1) that enables long-lasting transgene expression. Mice received injections in the anterior LV wall of rAAV/LacZ (LacZ group) or rAAV/HO-1 (HO-1 group); 1 year later, they were subjected to a 30-min coronary occlusion (O) and 4 h of reperfusion (R). Cardiac HO-1 gene expression was confirmed at 1 month and 1 year after gene transfer by immunoblotting and immunohistochemistry analyses. In the HO-1 group, infarct size (% of risk region) was dramatically reduced at 1 year after gene transfer (11.2 ± 2.1%, n = 12, vs. 44.7 ± 3.6%, n = 8, in the LacZ group; P < 0.05). The infarct-sparing effects of HO-1 gene therapy at 1 year were as powerful as those observed 24 h after ischemic PC (six 4-min O/4-min R cycles) (15.0 ± 1.7%, n = 10). There were no appreciable changes in LV fractional shortening, LV ejection fraction, or LV end-diastolic or end-systolic diameter at 1 year after HO-1 gene transfer as compared to the age-matched controls or with the LacZ group. Histology showed no inflammation in the myocardium 1 year after rAAV/HO-1-mediated gene transfer. These results demonstrate, for the first time, that rAAV-mediated HO-1 gene transfer confers long-term (1 year), possibly permanent, cardioprotection without adverse functional consequences, providing proof of principle for the concept of achieving prophylactic cardioprotection (i.e., "immunization against infarction").

Effects that different types of sports have on the hearts of children and adolescents and the value of two-dimensional strain-strain-rate echocardiography.

PubMed

Binnetoğlu, Fatih Köksal; Babaoğlu, Kadir; Altun, Gürkan; Kayabey, Özlem

2014-01-01

Whether the hypertrophy found in the hearts of athletes is physiologic or a risk factor for the progression of pathologic hypertrophy remains controversial. The diastolic and systolic functions of athletes with left ventricular (LV) hypertrophy usually are normal when measured by conventional methods. More precise assessment of global and regional myocardial function may be possible using a newly developed two-dimensional (2D) strain echocardiographic method. This study evaluated the effects that different types of sports have on the hearts of children and adolescents and compared the results of 2D strain and strain-rate echocardiographic techniques with conventional methods. Athletes from clubs for five different sports (basketball, swimming, football, wrestling, and tennis) who had practiced regularly at least 3 h per week during at least the previous 2 years were included in the study. The control group consisted of sedentary children and adolescents with no known cardiac or systemic diseases (n = 25). The athletes were grouped according to the type of exercise: dynamic (football, tennis), static (wrestling), or static and dynamic (basketball, swimming). Shortening fraction and ejection fraction values were within normal limits for the athletes in all the sports disciplines. Across all 140 athletes, LV geometry was normal in 58 athletes (41.4 %), whereas 22 athletes (15.7 %) had concentric remodeling, 20 (14.3 %) had concentric hypertrophy, and 40 (28.6 %) had eccentric hypertrophy. Global LV longitudinal strain values obtained from the average of apical four-, two-, and three-chamber global strain values were significantly lower for the basketball players than for all the other groups (p < 0.001).

Genotyping of feline leukemia virus in Mexican housecats.

PubMed

Ramírez, Hugo; Autran, Marcela; García, M Martha; Carmona, M Ángel; Rodríguez, Cecilia; Martínez, H Alejandro

2016-04-01

Feline leukemia virus (FeLV) is a retrovirus with variable rates of infection globally. DNA was obtained from cats' peripheral blood mononuclear cells, and proviral DNA of pol and env genes was detected using PCR. Seventy-six percent of cats scored positive for FeLV using env-PCR; and 54 %, by pol-PCR. Phylogenetic analysis of both regions identified sequences that correspond to a group that includes endogenous retroviruses. They form an independent branch and, therefore, a new group of endogenous viruses. Cat gender, age, outdoor access, and cohabitation with other cats were found to be significant risk factors associated with the disease. This strongly suggests that these FeLV genotypes are widely distributed in the studied feline population in Mexico.

N-terminal B-type natriuretic peptide concentrations are similarly increased by 30 minutes of moderate and brisk walking in patients with coronary artery disease.

PubMed

Scharhag, Jürgen; Herrmann, Markus; Weissinger, Melanie; Herrmann, Wolfgang; Kindermann, Wilfried

2007-04-01

Elevated concentrations of B-type natriuretic peptide (BNP) and N-terminal pro- BNP (NT-proBNP) reflect elevated myocardial wall stress due to volume or pressure overload in cardiac disease. Recently, exercise-induced elevations of (NT-pro)BNP in coronary artery disease (CAD) patients have been reported to result from exercise-induced ischemia associated regional wall abnormalities. Therefore, the study aimed to examine NT-proBNP concentrations in patients with CAD after moderate and brisk walking (MW, BW). We hypothesized that BW induces higher increases than MW. In randomized order 14 patients with stable CAD (12 male symbol/2 female symbol; 63 +/- 9 years; LV ejection fraction: 59+/-9%) of a out-patient rehabilitation group performed MW with 4.5 +/- 0.6 km/h (mean heart rate: 80 +/- 11/min) or BWat their allowed upper exercise heart rate of 102+/-9/min with a speed of 6.2 +/- 0.6 km/h for 30 min on a tartan track on two separate days. Blood samples were taken before, immediately, 1 h, 3 h and 1 day after exercise to determine NT-proBNP and cardiac troponin T (cTnT). Echocardiographic LV function was determined before and 1 h after exercise. Median concentrations of NT-proBNP significantly increased from 222 to 295 ng/l (MW) and from 222 to 296 ng/l (BW) without a difference between both modalities. cTnT remained below the detection limit of 0.01 microg/l. LV functions remained unchanged. A cutoff level of 250 ng/l distinguished CAD patients with elevated exercise-induced increases in NT-proBNP and a diminished LV ejection fraction at rest. BW and MW induce similar increases in NT-proBNP in CAD patients without myocardial damage, which have to be considered when NT-proBNP is determined. Derived from the exercise- induced increase in NTproBNP, the myocardial strain in BW is not elevated in comparison to MW.

Patients with a hypertensive response to exercise have impaired left ventricular diastolic function.

PubMed

Takamura, Takeshi; Onishi, Katsuya; Sugimoto, Tadafumi; Kurita, Tairo; Fujimoto, Naoki; Dohi, Kaoru; Tanigawa, Takashi; Isaka, Naoki; Nobori, Tsutomu; Ito, Masaaki

2008-02-01

An exaggerated increase in systolic blood pressure prolongs myocardial relaxation and increases left ventricular (LV) chamber stiffness, resulting in an increase in LV filling pressure. We hypothesize that patients with a marked hypertensive response to exercise (HRE) have LV diastolic dysfunction leading to exercise intolerance, even in the absence of resting hypertension. We recruited 129 subjects (age 63+/-9 years, 64% male) with a preserved ejection fraction and a negative stress test. HRE was evaluated at the end of a 6-min exercise test using the modified Bruce protocol. Patients were categorized into three groups: a group without HRE and without resting hypertension (control group; n=30), a group with HRE but without resting hypertension (HRE group; n=25), and a group with both HRE and resting hypertension (HTN group; n=74). Conventional Doppler and tissue Doppler imaging were performed at rest. After 6-min exercise tests, systolic blood pressure increased in the HRE and HTN groups, compared with the control group (226+/-17 mmHg, 226+/-17 mmHg, and 180+/-15 mmHg, respectively, p<0.001). There were no significant differences in LV ejection fraction, LV end-diastolic diameter, and early mitral inflow velocity among the three groups. However, early diastolic mitral annular velocity (E') was significantly lower and the ratio of early diastolic mitral inflow velocity (E) to E' (E/E') was significantly higher in patients of the HRE and HTN groups compared to controls (E': 5.9+/-1.6 cm/s, 5.9+/-1.7 cm/s, 8.0+/-1.9 cm/s, respectively, p<0.05). In conclusion, irrespective of the presence of resting hypertension, patients with hypertensive response to exercise had impaired LV longitudinal diastolic function and exercise intolerance.

Current Status of 3-Dimensional Speckle Tracking Echocardiography: A Review from Our Experiences

PubMed Central

Ishizu, Tomko; Aonuma, Kazutaka

2014-01-01

Cardiac function analysis is the main focus of echocardiography. Left ventricular ejection fraction (LVEF) has been the clinical standard, however, LVEF is not enough to investigate myocardial function. For the last decade, speckle tracking echocardiography (STE) has been the novel clinical tool for regional and global myocardial function analysis. However, 2-dimensional imaging methods have limitations in assessing 3-dimensional (3D) cardiac motion. In contrast, 3D echocardiography also has been widely used, in particular, to measure LV volume measurements and assess valvular diseases. Joining the technology bandwagon, 3D-STE was introduced in 2008. Experimental studies and clinical investigations revealed the reliability and feasibility of 3D-STE-derived data. In addition, 3D-STE provides a novel deformation parameter, area change ratio, which have the potential for more accurate assessment of overall and regional myocardial function. In this review, we introduced the features of the methodology, validation, and clinical application of 3D-STE based on our experiences for 7 years. PMID:25031794

Relation between aortic knob width and subclinical left ventricular dysfunction in hypertensive patients.

PubMed

Gürbak, İsmail; Yıldız, İbrahim; Panç, Cafer

2018-01-29

The assessment of left ventricular (LV) structure and function is important in the evaluation of hypertensive heart disease, as it provides information on the cardiovascular morbidity and mortality. Aortic knob width (AKW) is a measurement of radiographic structure formed by the foreshortened aortic arch and a portion of the descending aorta. The main aim of this study was to investigate the relation between AKW on the routine chest radiography and subclinical LV dysfunction in hypertensive patients. A total of 144 patients with hypertension admitted to the cardiology outpatients clinic were enrolled consecutively. The patients were divided into two groups according to tissue Doppler-derived myocardial performance index (MPI): subclinical LV dysfunction group (abnormal MPI ≥ 0.5, n = 85) and absence of subclinical LV dysfunction group (normal MPI< 0.5, n = 59). Patients with subclinical LV dysfunction were older (60 ± 8 vs. 54 ± 8, p = 0.001). Left ventricular mass index (LVMI) (96 ± 27 vs. 74 ± 24, p < 0.001) and prevalence of LV hypertrophy (28 vs. 8%, p = 0.011) were significantly different between two groups. Patients with subclinical LV dysfunction had higher AKW (42 ± 6 vs. 34 ± 5, p < 0.001) compared with patients without subclinical LV dysfunction. There was a significant correlation between MPI and AKW (r = 0.7, p < 0.001). Multiple logistic regression analysis showed that AKW (β = 0.617, p = 0.001) and posterior wall thickness (PWth) (β = 1.189, p = 0.021) were independently associated with subclinical LV dysfunction. Analysis using the Receiver Operating Characteristic (ROC) curve has demonstrated that aortic knob of 37 mm constitutes the cutoff value for the presence of subclinical LV dysfunction with 85.9% sensitivity and 86.4% specificity (The Area under the Curve ± Standard Error (AUC±SE) = 0.916 ± 0.024, p < 0.001). AKW may provide important predictive information on subclinical LV dysfunction in patients with hypertension.

Association of Socioeconomic Status in Childhood With Left Ventricular Structure and Diastolic Function in Adulthood: The Cardiovascular Risk in Young Finns Study.

PubMed

Laitinen, Tomi T; Puolakka, Elina; Ruohonen, Saku; Magnussen, Costan G; Smith, Kylie J; Viikari, Jorma S A; Heinonen, Olli J; Kartiosuo, Noora; Hutri-Kähönen, Nina; Kähönen, Mika; Jokinen, Eero; Laitinen, Tomi P; Tossavainen, Päivi; Pulkki-Råback, Laura; Elovainio, Marko; Raitakari, Olli T; Pahkala, Katja; Juonala, Markus

2017-08-01

Increased left ventricular (LV) mass and diastolic dysfunction are associated with cardiovascular disease. Prospective data on effects of childhood socioeconomic status (SES) on measures of LV structure and function are lacking. To examine whether family SES in childhood was associated with LV mass and diastolic function after adjustment for conventional cardiovascular disease risk factors in childhood and adulthood. The analyses were performed in 2016 using data gathered in 1980 and 2011 within the longitudinal population-based Cardiovascular Risk in Young Finns Study. The sample comprised 1871 participants who reported family SES at ages 3 to 18 years and were evaluated for LV structure and function 31 years later. Socioeconomic status was characterized as annual income of the family and classified on a 3-point scale. Left ventricular mass indexed according to height at the allometric power of 2.7 and the E/e' ratio describing LV diastolic performance at ages 34 to 49 years. The participants were aged 3 to 18 years at baseline (mean [SD], 10.8 [5.0] years), and the length of follow-up was 31 years. Family SES was inversely associated with LV mass (mean [SD] LV mass index, 31.8 [6.7], 31.0 [6.6], and 30.1 [6.4] g/m2.7 in the low, medium, and high SES groups, respectively; differences [95% CI], 1.7 [0.6 to 2.8] for low vs high SES; 0.8 [-0.3 to 1.9] for low vs medium; and 0.9 [0.1 to 1.6] for medium vs high; overall P = .001) and E/e' ratio (mean [SD] E/e' ratio, 5.0 [1.0], 4.9 [1.0], and 4.7 [1.0] in the low, medium, and high SES groups, respectively; differences [95% CI], 0.3 [0.1 to 0.4] for low vs high SES; 0.1 [-0.1 to 0.3] for low vs medium; and 0.2 [0 to 0.3] for medium vs high; overall P < .001) in adulthood. After adjustment for age, sex, and conventional cardiovascular disease risk factors in childhood and adulthood, and participants' own SES in adulthood, the relationship with LV mass (differences [95% CI], 1.5 [0.2 to 2.8] for low vs high SES; 1.3 [0 to 2.6] for low vs medium; and 0.2 [-0.6 to 1.0] for medium vs high; P = .03) and E/e' ratio (differences [95% CI], 0.2 [0 to 0.5] for low vs high SES; 0.1 [-0.1 to 0.4] for low vs medium; and 0.1 [0 to 0.3] for medium vs high; P = .02) remained significant. Low family SES was associated with increased LV mass and impaired diastolic performance more than 3 decades later. These findings emphasize that approaches of cardiovascular disease prevention must be directed also to the family environment of the developing child.

Serum bicarbonate and structural and functional cardiac abnormalities in CKD - A report from the CRIC study

PubMed Central

Dobre, Mirela; Roy, Jason; Tao, Kaixiang (Kelvin); Anderson, Amanda; Bansal, Nisha; Chen, Jing; Deo, Raj; Drawz, Paul; Feldman, Harold; Hamm, LL; Hostetter, Thomas; Kusek, John W; Lora, Claudia; Ojo, Akinlolu; Sharma, Kumar; Rahman, Mahboob

2016-01-01

Background Heart failure (HF) is a frequent occurrence in chronic kidney disease (CKD) patients and predicts poor survival. Serum bicarbonate is associated with increased rates of HF in CKD; however, the mechanisms leading to this association are incompletely understood. This study aims to assess whether serum bicarbonate is independently associated with structural and functional cardiac abnormalities in CKD. Methods The association between serum bicarbonate and left ventricular hypertrophy (LVH), LV mass indexed to height2.7, LV geometry, ejection fraction and diastolic dysfunction were assessed in 3483 participants without NYHA class III/IV HF, enrolled in the Chronic Renal Insufficiency Cohort (CRIC) study. Results The mean eGFR was 42.5±17ml/min per 1.73m2. The overall prevalence of LVH was 51.2%, with 57.8%, 50.9% and 47.7% for bicarbonate categories <22, 22-26, and >26mmol/L, respectively. Participants with low bicarbonate were more likely to have LVH and abnormal LV geometry (OR 1.32; 95%CI 1.07–1.64, and 1.57; 95%CI 1.14–2.16, respectively). However, the association was not statistically significant after adjustment for demographics, traditional cardiovascular risk factors, medications and kidney function (OR1.07; 95%CI 0.66–1.72, and 1.27; 95%CI 0.64–2.51, respectively). No association was found between bicarbonate and systolic or diastolic dysfunction. During follow-up no significant changes in LV mass or EF were observed in any bicarbonate strata. Conclusions In a large CKD study, serum bicarbonate was associated with LV mass and concentric LVH; however, this association was attenuated after adjustment for clinical factors suggesting that the observed cardiac effects are mediated through yet unknown mechanisms. PMID:27241893

Long-term cardiac abnormalities after cranial radiotherapy in childhood cancer survivors.

PubMed

Hummel, Yoran M; Hooimeijer, Hélène L; Zwart, Nynke; Tissing, Wim J E; Gietema, Jourik A; Voors, Adriaan A; van den Berg, Maarten P

2015-04-01

Cardiac morbidity is an important late effect in long-term childhood cancer survivors (CCS) treated with cardiotoxic agents or radiotherapy (RT) on the chest. However, there is limited data on the long-term cardiac sequelae in CCS who only received cranial RT. We hypothesized that cranial RT might negatively influence cardiac structure and function. We studied 13 CCS [mean age 30.8 (18.1-39.3) years, 7 males] who received RT only on the head for a cranial tumor and 36 age- and sex-matched healthy sibling controls. Echocardiographic follow-up was performed at median 21.7 (12.6-30.8) years after diagnosis. CCS had lower indexed diastolic LV volumes [56.0 (31.4-68.3) vs. 60.5 (41.9-94.3) mL/m(2), p = 0.024]. CCS also had reduced LV systolic and diastolic function, reflected by lower systolic LV myocardial velocities (5.3 ± 0.9 vs. 7.1 ± 1.7 cm/s, p = 0.001) and longitudinal deformation (- 17.3 ± 3.1 vs. - 20.7 ± 2.0%, p < 0.001), as well as lower diastolic LV myocardial velocities (- 10.7 ± 1.7 vs. - 12.2 ± 1.5 cm/s, p = 0.006) and deformation speed (1.1 ± 0.3 vs. 1.5 ± 0.2 1/s, p = 0.005). Additionally, in CCS insulin-like growth factor levels [15.4 (9.2-34.6) vs. 24.4 (14.8-55.5) nmol/L, p = 0.007] were lower. Cranial RT in CCS is associated with smaller cardiac volumes and reduced systolic and diastolic LV function. This off target effect of RT might be related to lower insulin-like growth factor levels.

Effect of dietary sodium and potassium intake on left ventricular diastolic function and mass in adults≤40 years (from the Strong Heart Study).

PubMed

Haring, Bernhard; Wang, Wenyu; Lee, Elisa T; Jhamnani, Sunny; Howard, Barbara V; Devereux, Richard B

2015-05-01

The aim of this study was to investigate whether intake of dietary sodium or potassium is related to changes in left ventricular (LV) diastolic functioning and LV mass index in young subjects with normal or elevated blood pressure. We prospectively analyzed echocardiographic data in 1,065 young adults (18 to 39 years) enrolled in the Strong Heart Family Study who were free from cardiovascular disease at baseline: 501 (47%) participants were normotensive and 564 (53%) were prehypertensive or hypertensive. Dietary sodium and potassium intakes were ascertained using a block food frequency questionnaire at baseline. Cardiac geometry and functioning were assessed at baseline and 4 years later. Marginal models were used to assess the associations of average intakes of sodium and potassium with echocardiographic measures. Participants with prehypertension or hypertension were older, had higher body mass index, and reported higher intakes of sodium than normotensive subjects at baseline. In prospective analyses, potassium intake was found to be negatively related to mitral E velocity (p=0.029) in normotensive subjects, whereas sodium/potassium ratio was positively associated with atrial filling fraction (p=0.017). In prehypertensive or hypertensive participants, sodium consumption was positively associated with atrial filling fraction (p=0.034) and an increase in sodium/potassium ratio was related to higher LV mass index (p=0.046). In conclusion, an increase in dietary sodium/potassium ratio was related to an accentuation of atrial phase LV diastolic filling in normotensive young subjects, whereas in prehypertensive or hypertensive subjects it was associated with higher LV mass index. Copyright © 2015 Elsevier Inc. All rights reserved.

A morpho-functional study using PEP/LVET ratio and global longitudinal strain in patients with dilated cardiomyopathy.

PubMed

Corîci, Oana Maria; Tănasie, Cornelia Andreea; Alexandru, Dragoş Ovidiu; Florescu, Mihaela Corina; Comănescu, Maria Victoria; Kamal, Kamal Constantin; Ţenea-Cojan, Tiberiu Ştefăniţă; Iancău, Maria; Dinescu, Sorin Nicolae

2018-01-01

To assess left ventricular (LV) systolic function and morphology in patients with severe dilated cardiomyopathy (DCM), using both conventional and a complex technique, speckle-tracking echocardiography, and evaluate the correlation between pre-ejection period and left ventricular ejection period (PEP/LVET) ratio, global longitudinal strain (GLS), and severity of the condition. Seventeen patients were enrolled after rigorous criteria. Echocardiography was performed in conventional and speckle-tracking mode, in all patients with DCM, in sinus rhythm. LV dimensions, volumes and ejection fraction (LVEF) were measured. PEP/LVET ratio was obtained from apical 5-chamber axis and was defined as the time between QRS onset and LV ejection reported to LV ejection period. Speckle-tracking imaging was performed in offline mode and GLS was obtained from parasternal 4-, 3-, 2-chamber apical view, by averaging longitudinal peak systolic strain of all 17 LV-segments. New York Heart Association (NYHA) functional class correlated significantly with LVEF (-0.82; p=0.0006), PEP/LVET (0.86; p=0.001) or GLS (0.85; p=0.0002). Considerable correlations were between mitral regurgitation (MR) severity and LVEF (-0.65; p=0.01) or PEP/LVET (0.69; p=0.0059), but higher were between MR severity and GLS (0.76; p=0.0018). Tricuspid regurgitation (TR) grading correlated statistically with LVEF (-0.62; p=0.01), PEP/LVET and GLS (0.6; p=0.018; and 0.62; p=0.014, respectively). As opposed to the parameters in conventional echocardiography, GLS correlated with DCM etiology (p=0.0046) and with the gender (p=0.048). This study demonstrates that, in patients with DCM, assessment of cardiac dyssynchrony can be accurately accomplished by combining parameters in conventional and in speckle-tracking echocardiography.

The impact of anabolic androgenic steroids abuse and type of training on left ventricular remodeling and function in competitive athletes.

PubMed

Ilić, Ivan; Djordjević, Vitomir; Stanković, Ivan; Vlahović-Stipac, Alja; Putniković, Biljana; Babić, Rade; Nesković, Aleksandar N

2014-04-01

Long-term intensive training is associated with distinctive cardiac adaptations which are known as athlete's heart. The aim of this study was to determine whether the use of anabolic androgenic steroids (AAS) could affect echocardiographic parameters of left ventricular (LV) morphology and function in elite strength and endurance athletes. A total of 20 elite strength athletes (10 AAS users and 10 non-users) were compared to 12 steroid-free endurance athletes. All the subjects underwent comprehensive standard echocardiography and tissue Doppler imaging. After being indexed for body surface area, both left atrium (LA) and LV end-diastolic diameter (LVEDD) were significantly higher in the endurance than strength athletes, regardless of AAS use (p < 0.05, for both). A significant correlation was found between LA diameter and LVEDD in the steroid-free endurance athletes, showing that 75% of LA size variability depends on variability of LVEDD (p < 0.001). No significant differences in ejection fraction and cardiac output were observed among the groups, although mildly reduced LV ejection fraction was seen only in the AAS users. The AAS-using strength athletes had higher A-peak velocity when compared to steroid-free athletes, regardless of training type (p < 0.05 for both). Both AAS-using and AAS-free strength athletes had lower e' peak velocity and higher E/e' ratio than endurance athletes (p < 0.05, for all). There is no evidence that LV ejection fraction in elite athletes is altered by either type of training or AAS misuse. Long-term endurance training is associated with preferable effects on LV diastolic function compared to strength training, particularly when the latter is combined with AAS abuse.

INCREASED MYOCARDIAL STIFFNESS DUE TO CARDIAC TITIN ISOFORM SWITCHING IN A MOUSE MODEL OF VOLUME OVERLOAD LIMITS ECCENTRIC REMODELING

PubMed Central

Hutchinson, Kirk R; Saripalli, Chandra; Chung, Charles S.; Granzier, Henk

2014-01-01

We investigated the cellular and molecular mechanisms of diastolic dysfunction in pure volume overload induced by aortocaval fistula (ACF) surgery in the mouse. Four weeks of volume overload resulted in significant biventricular hypertrophy; protein expression analysis in left ventricular (LV) tissue showed a marked decrease in titin's N2BA/N2B ratio with no change in phosphorylation of titin's spring region. Titin-based passive tensions were significantly increased; a result of the decreased N2BA/N2B ratio. Conscious echocardiography in ACF mice revealed eccentric remodeling and pressure volume analysis revealed systolic dysfunction: reductions in ejection fraction (EF), +dP/dt, and the slope of the endsystolic pressure volume relationships (ESPVR). ACF mice also had diastolic dysfunction: increased LV end-diastolic pressure and reduced relaxation rates. Additionally, a decrease in the slope of the end diastolic pressure volume relationship (EDPVR) was found. However, correcting for altered geometry of the LV normalized the change in EDPVR and revealed, in line with our skinned muscle data, increased myocardial stiffness in vivo. ACF mice also had increased expression of the signaling proteins FHL-1, FHL-2, and CARP that bind to titin's spring region suggesting that titin stiffening is important to the volume overload phenotype. To test this we investigated the effect of volume overload in the RBM20 heterozygous (HET) mouse model, which exhibits reduced titin stiffness. It was found that LV hypertrophy was attenuated and that LV eccentricity was exacerbated. We propose that pure volume overload induces an increase in titin stiffness that is beneficial and limits eccentric remodeling. PMID:25450617

Lesion volume predicts prostate cancer risk and aggressiveness: validation of its value alone and matched with prostate imaging reporting and data system score.

PubMed

Martorana, Eugenio; Pirola, Giacomo Maria; Scialpi, Michele; Micali, Salvatore; Iseppi, Andrea; Bonetti, Luca Reggiani; Kaleci, Shaniko; Torricelli, Pietro; Bianchi, Giampaolo

2017-07-01

To demonstrate the association between magnetic resonance imaging (MRI) estimated lesion volume (LV), prostate cancer detection and tumour clinical significance, evaluating this variable alone and matched with Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) score. We retrospectively analysed 157 consecutive patients, with at least one prior negative systematic prostatic biopsy, who underwent transperineal prostate MRI/ultrasonography fusion-targeted biopsy between January 2014 and February 2016. Suspicious lesions were delineated using a 'region of interest' and the system calculated prostate volume and LV. Patients were divided in groups considering LV (≤0.5, 0.5-1, ≥1 mL) and PI-RADS score (1-5). We considered clinically significant prostate cancer as all cancers with a Gleason score of ≥3 + 4 as suggested by PI-RADS v2. A direct comparison between MRI estimated LV (MRI LV) and histological tumour volume (HTV) was done in 23 patients who underwent radical prostatectomy during the study period. Differences between MRI LV and HTV were assessed using the paired sample t-test. MRI LV and HTV concordance was verified using a Bland-Altman plot. The chi-squared test and logistic and ordinal regression models were used to evaluate difference in frequencies. The MRI LV and PI-RADS score were associated both with prostate cancer detection (both P < 0.001) and with significant prostate cancer detection (P < 0.001 and P = 0.008, respectively). When the two variables were matched, increasing LV increased the risk within each PI-RADS group. Prostate cancer detection was 1.4-times higher for LVs of 0.5-1 mL and 1.8-times higher for LVs of ≥1 mL; significant prostate cancer detection was 2.6-times for LVs of 0.5-1 mL and 4-times for LVs of ≥1 mL. There was a positive correlation between MRI LV and HTV (r = 0.9876, P < 0.001). Finally, Bland-Altman analysis showed that MRI LV was underestimated by 4.2% compared to HTV. Study limitations include its monocentric and retrospective design and the limited cohort. This study demonstrates that PI-RADS score and the MRI LV, independently and in combination, are associated with prostate cancer detection and with tumour clinical significance. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

Ergotamine-derived dopamine agonists and left ventricular function in Parkinson patients: systolic and diastolic function studied by conventional echocardiography, tissue Doppler imaging, and two-dimensional speckle tracking.

PubMed

Rasmussen, Vibeke Guldbrand; Poulsen, Steen Hvitfeldt; Dupont, Erik; Ostergaard, Karen; Safikhany, Gholamhossein; Egeblad, Henrik

2008-11-01

Ergot-derived dopamine agonists (EDDA) induce fibrotic heart valve disease. We aimed to investigate whether EDDA treatment also affects left ventricular (LV) function. Myocardial function was evaluated in 110 Parkinson patients [mean age (63.4 +/- 9.0 years)] treated for at least 6 months with either EDDA (n = 71) or non-EDDA (n = 39). LV ejection fraction did not differ between EDDA and non-EDDA patients [63 +/- 4% vs. 65 +/- 4% (ns)]. There was no difference in prevalence of diastolic dysfunction between EDDA and non-EDDA patients [7% vs. 8% (ns)]. Finally, averaged LV systolic myocardial strain and longitudinal displacement analysed by means of two-dimensional speckle tracking showed no difference between EDDA and non-EDDA patients [strain: 19 +/- 3% vs. 19 +/- 2% (ns) and longitudinal displacement: 12 +/- 2 mm vs. 12 +/- 2 mm (ns)]. Elevated p-NT-proBNP was found in 38% of EDDA patients and in 59% of non-EDDA patients (ns). In contrast to the well-established association between EDDA treatment and valvular fibrosis, EDDA did not have a detectable adverse impact on myocardial systolic and diastolic function.

Longitudinal assessment of short-term memory deterioration in a logopenic variant primary progressive aphasia with post-mortem confirmed Alzheimer's Disease pathology.

PubMed

Tree, Jeremy; Kay, Janice

2015-09-01

In the field of dementia research, there are reports of neurodegenerative cases with a focal loss of language, termed primary progressive aphasia (PPA). Currently, this condition has been further sub-classified, with the most recent sub-type dubbed logopenic variant (PPA-LV). As yet, there remains somewhat limited evaluation of the characteristics of this condition, with no studies providing longitudinal assessment accompanied by post-mortem examination. Moreover, a key characteristic of the PPA-LV case is a deterioration of phonological short-term memory, but again little work has scrutinized the nature of this impairment over time. The current study seeks to redress these oversights and presents detailed longitudinal examination of language and memory function in a case of PPA-LV, with special focus on tests linked to components of phonological short-term memory function. Our findings are then considered with reference to a contemporary model of the neuropsychology of phonological short-term memory. Additionally, post-mortem examinations indicated Alzheimer's disease type pathology, providing further evidence that the PPA-LV presentation may reflect an atypical presentation of this condition. © 2014 The British Psychological Society.

Episodic and working memory function in Primary Progressive Aphasia: A meta-analysis.

PubMed

Eikelboom, Willem S; Janssen, Nikki; Jiskoot, Lize C; van den Berg, Esther; Roelofs, Ardi; Kessels, Roy P C

2018-06-18

The distinction between Primary Progressive Aphasia (PPA) variants remains challenging for clinicians, especially for the non-fluent (nfv-PPA) and the logopenic variants (lv-PPA). Previous research suggests that memory tests might aid this differentiation. This meta-analysis compares memory function among PPA variants. Effects sizes were extracted from 41 studies (N = 849). Random-effects models were used to compare performance on episodic and working memory tests among PPA patients and healthy controls, and between the PPA variants. Memory deficits were frequently observed in PPA compared to controls, with large effect sizes for lv-PPA (Hedges' g = -2.04 [-2.58 to -1.49]), nfv-PPA (Hedges' g = -1.34 [-1.69 to -1.00]), and the semantic variant (sv-PPA; Hedges' g = -1.23 [-1.50 to -0.97]). Sv-PPA showed primarily verbal memory deficits, whereas lv-PPA showed worse performance than nfv-PPA on both verbal and non-verbal memory tests. Memory deficits were more pronounced in lv-PPA compared to nfv-PPA. This suggests that memory tests may be helpful to distinguish between these PPA variants. Copyright © 2018. Published by Elsevier Ltd.

Isolation and cDNA cloning of a novel red colour-related pigment-binding protein derived from the shell of the shrimp, Litopenaeus vannamei.

PubMed

Pan, Chuang; Ishizaki, Shoichiro; Nagashima, Yuji; Gao, Jialong; Watabe, Shugo

2018-02-15

Pigment-binding proteins play important roles in crustacean shell colour change. In this study, a red colour-related pigment-binding protein, designated LvPBP75, was purified from the shell of Litopenaeus vannamei. HPLC and PAGE analysis showed that LvPBP75 was a homogeneous monomer with molecular mass of 75kDa. Peptide mass fingerprint analysis revealed that LvPBP75 belonged to hemocyanin, and the released pigment from heated LvPBP75 showed a λ max at 481nm in acetone. The significant red-colour change temperatures were detected at 30 and 80°C, respectively. Based on the determined amino acid fragments, a full-length cDNA of LvPBP75 was cloned and sequenced. The ORF encodes a protein of 662 amino acids having 80% identity with penaeidae hemocyanin. These results strongly suggest a novel function of hemocyanin, namely binding with pigment, and its involvement in L. vannamei shell colour change. Copyright © 2017 Elsevier Ltd. All rights reserved.

HIV-derived vectors for gene therapy targeting dendritic cells.

PubMed

Rossetti, Maura; Cavarelli, Mariangela; Gregori, Silvia; Scarlatti, Gabriella

2013-01-01

Human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LV) have the potential to mediate stable therapeutic gene transfer. However, similarly to other viral vectors, their benefit is compromised by the induction of an immune response toward transgene-expressing cells that closely mimics antiviral immunity. LV share with the parental HIV the ability to activate dendritic cells (DC), while lack the peculiar ability of subverting DC functions, which is responsible for HIV immune escape. Understanding the interaction between LV and DC, with plasmacytoid and myeloid DC playing fundamental and distinct roles, has paved the way to novel approaches aimed at regulating transgene-specific immune responses. Thanks to the ability to target either DC subsets LV might be a powerful tool to induce immunity (i.e., gene therapy of cancer), cell death (i.e., in HIV/AIDS infection), or tolerance (i.e., gene therapy strategies for monogenic diseases). In this chapter, similarities and differences between the LV-mediated and HIV-mediated induction of immune responses, with specific focus on their interactions with DC, are discussed.

Correlation between plasma N-terminal pro-brain natriuretic peptide levels and changes in New York Heart Association functional class, left atrial size, left ventricular size and function after mitral and/or aortic valve replacement.

PubMed

Elasfar, Abdelfatah

2012-01-01

Elevated plasma brain natriuretic peptide (BNP) levels have been demonstrated in patients with chronic valvular disease. We designed the present study to assess whether changes in N-terminal pro-brain natriuretic peptide (NT-proBNP) levels after mitral, aortic and double mitral and aortic valve replacement reflect changes in heart failure (HF) symptoms including New York Heart Association (NYHA) class and changes in left atrium (LA) size, left ventricle (LV) size and LV function. A prospective observational nonrandomized study among consecutive patients undergoing mitral and/or aortic valve replacement in our center. The study population consisted of 24 patients (mean [SD] age of 55.3 [16.2] years, 58% were males) who underwent surgical mitral valve replacement (12 patients), aortic valve replacement (8 patients) and combined mitral and aortic valve replacement (4 patients). NT-proBNP measurements, transthoracic echocardiography and NYHA class assessments were performed before and 6 months after surgery. The decrease in NT-proBNP was associated with decrease in left atrial dimension (r = 0.73, P < .002), LV end-diastolic dimension (r=0.65, P=.001), LV end-systolic dimension (r=0.53, P=.036), and increase in ejection fraction (r=-0.65, P=.001) after 6 months postoperatively. Furthermore, a decreasing NT-proBNP was associated with improvement in NYHA class. NT-proBNP levels after mitral, aortic and double valve replacement correlates with changes in HF manifestations as well as changes in LA size and LV dimension and function. Thus, we hypothesize that interval measurement of the NT-proBNP level at clinic visits can allow early detection of any clinical deterioration as well as the possibility of assessment of the long-term outcome of those patients.

Assessment of aortic stiffness in patients with ankylosing spondylitis using cardiovascular magnetic resonance.

PubMed

Biesbroek, P Stefan; Heslinga, Sjoerd C; van de Ven, Peter M; Peters, Mike J L; Amier, Raquel P; Konings, Thelma C; Maroules, Christopher D; Ayers, Colby; Joshi, Parag H; van der Horst-Bruinsma, Irene E; van Halm, Vokko P; van Rossum, Albert C; Nurmohamed, Michael T; Nijveldt, Robin

2018-05-12

To evaluate aortic stiffness in patients with ankylosing spondylitis (AS) using cardiovascular magnetic resonance (CMR) and to assess its association with AS characteristics and left ventricular (LV) remodeling. In this prospective study, 14 consecutive AS patients were each matched to two controls without cardiovascular symptoms or known cardiovascular disease who underwent CMR imaging for the assessment of aortic arch pulse wave velocity (PWV) at 1.5 Tesla. To enhance comparability of the samples, matching was done with replacement resulting in 20 unique controls. Only AS patients with abnormal findings on screening echocardiography were included in this exploratory study. Cine CMR was used to assess LV geometry and systolic function, and late gadolinium enhancement was performed to determine the presence of myocardial hyperenhancement (i.e., fibrosis). Aortic arch PWV was significantly higher in the AS group compared with the control group (median 9.7 m/s, interquartile range [IQR] 7.1 to 11.8 vs. 6.1 m/s, IQR 4.6 to 7.6 m/s; p < 0.001). PWV was positively associated with functional disability as measured by BASFI (R: 0.62; p = 0.018). Three patients (21%) with a non-ischemic pattern of hyperenhancement showed increased PWV (11.7, 12.3, and 16.5 m/s) as compared to the 11 patients without hyperenhancement (9.0 m/s, IQR 6.6 to 10.5 m/s; p = 0.022). PWV was inversely associated with LV ejection fraction (R: - 0.63; p = 0.015), but was not found to be statistically correlated to LV volumes or mass. Aortic arch PWV was increased in our cohort of patients with AS. Higher PWV in the aortic arch was associated with functional disability, the presence of non-ischemic hyperenhancement, and reduced LV systolic function.

Effect of fetal hypoxia on heart susceptibility to ischemia and reperfusion injury in the adult rat.

PubMed

Li, Guohu; Xiao, Yuhui; Estrella, Jaymie L; Ducsay, Charles A; Gilbert, Raymond D; Zhang, Lubo

2003-07-01

Epidemiologic studies showed an association between adverse intrauterine environment and ischemic heart disease in the adult. We tested the hypothesis that prenatal hypoxia increased the susceptibility of adult heart to ischemia-reperfusion (I-R) injury. Time-dated pregnant rats were divided between normoxic and hypoxic (10.5% oxygen from day 15 to 21) groups. Hearts of 6-month-old male progeny were studied using Langendorff preparation and were subjected to two protocols of I-R: 10 minutes of ischemia and 3 hours of reperfusion (I-R(10)) or 25 minutes of ischemia and 3 hours of reperfusion (I-R(25)). Prenatal hypoxia did not change basal left ventricular (LV) function. I-R(10) produced myocardial stunning and a transient decrease in LV function in control hearts but caused myocardial infarction and a persistent decrease in postischemic recovery of LV function in hypoxic hearts. I-R(25) caused myocardial infarction in both control and hypoxic hearts, which was significantly higher in hypoxic hearts. The postischemic recovery of LV function was significantly reduced in hypoxic hearts. I-R(25)-induced activation of caspase-3 and apoptosis in the left ventricle were significantly higher in hypoxic than control hearts. There was a significant decrease in LV heat shock protein 70 and endothelial nitric oxide synthase levels in hypoxic hearts. Prenatal hypoxia did not change beta(1)-adrenoreceptor levels but significantly increased beta(2)-adrenoreceptor in the left ventricle. In addition, it increased G(s)alpha but decreased G(i)alpha. Prenatal chronic hypoxia increases the susceptibility of adult heart to I-R injury. Several possible mechanisms may be involved, including an increase in beta(2)-adrenoreceptor and the G(s)alpha/G(i)alpha ratio, and a decrease in heat shock protein 70 and endothelial nitric oxide synthase in the left ventricle.

Reference ranges of left ventricular structure and function assessed by contrast-enhanced cardiac MR and changes related to ageing and hypertension in a population-based study.

PubMed

Bülow, Robin; Ittermann, Till; Dörr, Marcus; Poesch, Axel; Langner, Sönke; Völzke, Henry; Hosten, Norbert; Dewey, Marc

2018-03-14

Reference ranges of left ventricular (LV) parameters from cardiac magnetic resonance (CMR) were established to investigate the impact of ageing and hypertension as important determinants of cardiac structure and function. One thousand five hundred twenty-five contrast-enhanced CMRs were conducted in the Study of Health in Pomerania. LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), stroke volume (LVSV), ejection fraction (LVEF), and myocardial mass (LVMM) were determined using long- and short-axis steady-state free-precession sequences. The reference population was defined as participants without late enhancement, hypertension, and prior cardiovascular diseases. Reference ranges were established by quantile regression (5th and 95th percentile) and compared with an additional sample of treated and untreated hypertensives. LV volumes in the reference population (n = 634, 300 males, 334 females, 52.1 ± 13.3 years) aged between 20-69 years were lower with higher age (p = 0.001), whereas LVEFs were higher (p ≤ 0.020). LVMM was lower only in males (p = 0.002). Compared with the reference population, hypertension was associated with lower LVEDV in males (n = 258, p ≤ 0.032). Antihypertensive therapy was associated with higher LVEF in males (n = 258, +2.5%, p = 0.002) and females (n = 180, +2.1%, p = 0.001). Population-based LV reference ranges were derived from contrast-enhanced CMR. Hypertension-related changes were identified by comparing these values with those of hypertensives, and they might be used to monitor cardiac function in these patients. • Left ventricular function changed slightly but significantly between 20-69 years. • Reference values of BSA-indexed myocardial mass decreased with age in males. • Hypertension was associated with lower LV end-diastolic volume only in males. • CMR may allow assessing remodelling related to hypertension or antihypertensive treatment.

Body temperature circadian rhythm variability corresponds to left ventricular systolic dysfunction in decompensated cardiomyopathic hamsters.

PubMed

Ahmed, Amany; Gondi, Sreedevi; Cox, Casey; Zheng, Minjuan; Mohammed, Anwarullah; Stupin, Igor V; Wang, Suwei; Vela, Deborah; Brewer, Alan; Elayda, Macarthur A; Buja, L Maximilian; Ward Casscells, S; Wilson, James M

2011-11-01

A declining amplitude of body temperature circadian rhythm (BTCR) predicts decompensation or death in cardiomyopathic hamsters. We tested the hypothesis that changes in BTCR amplitude accompany significant changes in left ventricular (LV) size and function. Using intraperitoneal transmitters, we continuously monitored the temperature of 30 male BIO TO-2 Syrian dilated cardiomyopathic hamsters. Cosinor analysis was used to detect significant changes--defined as changes >1 standard deviation from the baseline amplitude for 3 consecutive days--in BTCR amplitude over each hamster's lifespan. The Student t-test was used to compare BTCR variability and LV size and function (as assessed by 2D echocardiography) between baseline and the time that BTCR amplitude declined. All hamsters received 10 mg/kg furosemide daily. At the time of BTCR amplitude decline, functional parameters had changed significantly (P < .0001) from baseline: ejection fraction (0.31 ± 0.09% vs. 0.52 ± 0.08%), LV end-systolic volume (0.11 ± 0.03 vs. 0.05 ± 0.02 cm(3)), and LV end-diastolic volume (0.16 ± 0.04 vs. 0.10 ± 0.03 cm(3)). In decompensated cardiomyopathic hamsters, a decline in BTCR amplitude was associated with progression of heart failure and cardiac decompensation. Variation in BTCR warrants further investigation because of its potential implications for the diagnosis and treatment of cardiovascular disorders. Published by Elsevier Inc.

Long-term low dose dietary resveratrol supplement reduces cardiovascular structural and functional deterioration in chronic heart failure in rats.

PubMed

Ahmet, Ismayil; Tae, Hyun-Jin; Lakatta, Edward G; Talan, Mark

2017-03-01

A short-term exposure to resveratrol at high dosages exerts a remarkable cardioprotective effect. Whether a long-term exposure to resveratrol at low dosages that can be obtained through consumption of a resveratrol-rich diet is beneficial to heart diseases is unknown. We tested the effects of a resveratrol-enriched diet on cardiovascular remodeling of chronic heart failure (CHF) in rats resulting from permanent ligation of left coronary artery. Two weeks after surgery, rats were started on either a resveratrol-enriched (R; 5 mg/kg per day; n = 23) or normal (Control; n = 23) diet for next 10 months. Serial echocardiography in Control showed a significant decline in LV ejection fraction, increases in LV end-systolic and end-diastolic volumes, and expansion in myocardial infarct from pre-treatment values. In R, compared with Control, there were substantial improvements in those parameters. End-point LV pressure-volume loop analysis showed a significantly improved LV systolic function and AV-coupling, an index of energy transfer efficacy between the heart and aortic tree, in R compared with Control (p < 0.05). Aortic pulse wave velocity, a measure of arterial stiffness, was significantly lower in R (389 ± 15 cm/s; p < 0.05) compared with Control (489 ± 38 cm/s). These results demonstrated that long-term dietary resveratrol supplement reduces cardiovascular structural and functional deterioration in CHF.

Prognostic heterogeneity of diastolic abnormalities along left ventricular remodeling continuum according to survival rates and laser polarimetry of blood

NASA Astrophysics Data System (ADS)

Boychuk, T. M.; Ivashchuk, O. I.; Kolomoiets, M. Y.; Mikhaliev, K. O.; Chursina, T. Y.

2011-09-01

The results of examination of 35 arterial hypertension and coronary heart disease patients are presented. The clinical, paraclinical and echocardiographic examinations were performed, and the parameters of prognosis (survival) according to Seattle Heart Failure Model, as well as the optical (polarimetric) properties of erythrocytic suspension were determined. The group of patients under examination was stratified by patterns of remodeling of left ventricle (LV). It was determined that increasing of anisotropy of erythrocytic suspension along LV remodeling patterns continuum correlates with aggravation of structural and functional state of LV and is associated with unfavorable prognosis.

Prognosis parameters and polarimetric properties of erythrocytes of the patients suffering from arterial hypertension and coronary heart disease at various patterns of left ventricular remodeling

NASA Astrophysics Data System (ADS)

Ivaschuk, Oleg I.; Kolomoiets, M. Y.; Mikhaliev, K. O.; Chursina, T. Ya.

2011-09-01

The results of examination of 35 arterial hypertension and coronary heart disease patients are presented. The clinical, paraclinical and echocardiographic examinations were performed, and the parameters of prognosis (survival) according to Seattle Heart Failure Model, as well as the optical (polarimetric) properties of erythrocytic suspension were determined. The group of patients under examination was stratified by patterns of remodeling of left ventricle (LV). It was determined that increasing of anisotropy of erythrocytic suspension along LV remodeling patterns continuum correlates with aggravation of structural and functional state of LV and is associated with unfavorable prognosis.

Left Ventricular Endocardium Tracking by Fusion of Biomechanical and Deformable Models

PubMed Central

Gu, Jason

2014-01-01

This paper presents a framework for tracking left ventricular (LV) endocardium through 2D echocardiography image sequence. The framework is based on fusion of biomechanical (BM) model of the heart with the parametric deformable model. The BM model constitutive equation consists of passive and active strain energy functions. The deformations of the LV are obtained by solving the constitutive equations using ABAQUS FEM in each frame in the cardiac cycle. The strain energy functions are defined in two user subroutines for active and passive phases. Average fusion technique is used to fuse the BM and deformable model contours. Experimental results are conducted to verify the detected contours and the results are evaluated by comparing themto a created gold standard. The results and the evaluation proved that the framework has the tremendous potential to track and segment the LV through the whole cardiac cycle. PMID:24587814

Static cardiomyoplasty with synthetic elastic net suppresses ventricular dilatation and dysfunction after myocardial infarction in the rat: a chronic study.

PubMed

Kato, Nobusuke; Kawaguchi, Akira T; Kishida, Akio; Yamaoka, Tetsuji

2013-07-01

Although static cardiomyoplasty prevents the left ventricle (LV) from dilatation, it may interfere with diastolic relaxation, or cause restriction. We developed a synthetic net with dual elasticity and tested its effect late after myocardial infarction in the rat. LV pressure-volume relationships (PVR) were successively analyzed before, after intravenous volume load, and 10 minutes after occlusion of the left anterior descending artery. Rats were then randomized into groups receiving synthetic net wrapping around the heart (NET+, n = 8) and only partially behind LV (NET-, n = 9), and they underwent the same PVR studies 6 weeks later. End-diastolic and end-systolic PVR were defined, and LV size and function were compared under standardized loading conditions. Although there was no difference in Day 0, increase in LV end-diastolic and end-systolic volumes were significantly attenuated in NET+ rats 6 weeks later when there was a significant correlation between LV volumes by PVR estimation and actual measurements, with significant differences in both measures between the groups: NET+ < NET-. The presence or absence of net did not show restrictive hemodynamics under acute volume load. Static cardiomyoplasty using a synthetic elastic net significantly attenuated LV dilatation and dysfunction without restriction late after myocardial infarction in the rat. © 2013, Copyright the Authors. Artificial Organs © 2013, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Characterization of alterations in diabetic myocardial tissue using high resolution MRI.

PubMed

Loganathan, Rajaprasad; Bilgen, Mehmet; Al-Hafez, Baraa; Smirnova, Irina V

2006-02-01

Cardiovascular complications, including diabetic cardiomyopathy, are the major cause of fatalities in diabetes. Diabetic cardiomyopathy is expressed in part through fibrosis and left ventricular hypertrophy, increasing myocardial stiffness leading to heart failure. In order to search for curative interventions, precise evaluation of the diabetic heart pathology is extremely important. Magnetic resonance imaging (MRI) is ideally suited for the assessment of heart disorders due to its high resolution, three-dimensional properties and dimensional accuracy. In this study streptozotocin injected Sprague-Dawley rats were used as a model of type 1 diabetes to characterize abnormalities in the diabetic left ventricle (LV). High resolution MRI using a 9.4 T horizontal bore scanner was performed on control and 7 weeks diabetic rats. In the diabetic rats as compared to controls, we found increased LV wall volume to body weight ratio, suggestive of LV hypertrophy; increased LV wall mean pixel intensity, and decreased T2 relaxation time, both suggestive of changes in the diabetic tissue properties, perhaps due to presence of fibrosis which was detected through increase in the collagen fractional area. In addition, changes in the LV cavity area were observed and quantified in post-mortem diabetic hearts indicative of stiffer and less resilient LV myocardial tissue with diabetes. Together the data suggest that LV hypertrophy and fibrosis may be a major factor underlying structural and functional abnormalities in the diabetic heart, and MRI is a valuable tool to non-invasively monitor the pathological changes in diabetic cardiomyopathy.

Clinical and ultrasound results after aortic valve replacement: intermediate-term follow-up with the St. Jude Medical prosthesis.

PubMed

Montalescot, G; Thomas, D; Drobinski, G; Evans, J I; Vicaut, E; Chatellier, G; Whyte, R I; Busquet, P; Bejean-Lebuisson, A; Grosgogeat, Y

1989-07-01

Mortality, morbidity, quality of life, and left ventricular (LV) function were evaluated in 49 patients after aortic valve replacement with the St. Jude prosthesis. Total follow-up was 2577 patient-months; survivors were followed-up for 4 to 7 years by clinical examination and echocardiography. The actuarial survival rate at 6 years was 79.6%, and there were no valve-related deaths. The linearized rates for thromboembolism and hemorrhage were 0.93% and 3.26% per patient-year, respectively. In 34% of the survivors the quality of life was poor. In the first three postoperative months, patients with aortic stenosis (n = 12) had a significant decrease in the muscle cross-sectional area (p less than 0.01) and patients with aortic regurgitation (n = 11) had decreases in both LV end-diastolic diameter (p less than 0.05) and cross-sectional area (p less than 0.001). All of these results were maintained at 5 years without modification of LV systolic function. Despite the good overall results, six patients deteriorated and had major LV dilatation. Multivariate logistic regression analysis identified two independent preoperative variables associated with a poor outcome defined as death of LV dysfunction (p less than 0.05): age and end-diastolic diameter. Thus meticulous follow-up showed a high incidence of hemorrhage and a poor quality of life in many of the survivors. It was concluded that in high-risk patients (age and end-diastolic diameter) surgery should probably be considered earlier.

Loxosceles gaucho Venom-Induced Acute Kidney Injury – In Vivo and In Vitro Studies

PubMed Central

Lucato, Rui V.; Abdulkader, Regina C. R. M.; Barbaro, Katia C.; Mendes, Glória E.; Castro, Isac; Baptista, Maria A. S. F.; Cury, Patrícia M.; Malheiros, Denise M. C.; Schor, Nestor; Yu, Luis; Burdmann, Emmanuel A.

2011-01-01

Background Accidents caused by Loxosceles spider may cause severe systemic reactions, including acute kidney injury (AKI). There are few experimental studies assessing Loxosceles venom effects on kidney function in vivo. Methodology/Principal Findings In order to test Loxosceles gaucho venom (LV) nephrotoxicity and to assess some of the possible mechanisms of renal injury, rats were studied up to 60 minutes after LV 0.24 mg/kg or saline IV injection (control). LV caused a sharp and significant drop in glomerular filtration rate, renal blood flow and urinary output and increased renal vascular resistance, without changing blood pressure. Venom infusion increased significantly serum creatine kinase and aspartate aminotransferase. In the LV group renal histology analysis found acute epithelial tubular cells degenerative changes, presence of cell debris and detached epithelial cells in tubular lumen without glomerular or vascular changes. Immunohistochemistry disclosed renal deposition of myoglobin and hemoglobin. LV did not cause injury to a suspension of fresh proximal tubules isolated from rats. Conclusions/Significance Loxosceles gaucho venom injection caused early AKI, which occurred without blood pressure variation. Changes in glomerular function occurred likely due to renal vasoconstriction and rhabdomyolysis. Direct nephrotoxicity could not be demonstrated in vitro. The development of a consistent model of Loxosceles venom-induced AKI and a better understanding of the mechanisms involved in the renal injury may allow more efficient ways to prevent or attenuate the systemic injury after Loxosceles bite. PMID:21655312

Can body surface microvolt T-wave alternans distinguish concordant and discordant intracardiac alternans?

PubMed

Floré, Vincent; Claus, Piet; Symons, Rolf; Smith, Godfrey L; Sipido, Karin R; Willems, Rik

2013-08-01

There is convincing experimental evidence that cellular action potential duration (APD) alternans is arrhythmogenic but its relationship with body surface microvolt T-wave alternans (MTWA) remains unclear. We investigated the relationship between MTWA and APD alternans induced by alternating cycle length (CL) pacing in a pig model. In 10 pigs, catheters in the right atrium (RA) and right (RV) and left ventricle (LV) allowed pacing and recording of monophasic action potentials (MAP). During RA pacing at stable 500-ms CL, LV was paced at alternating CL (505 ms and 495 ms). Changing the alternating LV (A-LV) pacing delay changes the size of the region with alternating ventricular activation. Spectral analysis of intracardiac MAP was correlated with body surface MTWA. In a similar setup (during alternating pacing in RV and LV), we investigated concordant versus discordant APD alternans. Pacing the LV with subtle alternating cycle lengths at short A-LV delay leads to broad QRS (97 ± 10 ms), body surface MTWA (mean Valt 4.2 ± 1.8 µV), and positive RR-interval alternans. At longer A-LV delay, not resulting in QRS widening (68 ± 5 ms), body surface RR alternans was absent but MTWA remained detectable and was even more pronounced (8.7 ± 5.1 µV, P < 0.01). During both concordant and discordant pacing MTWA was present. The precordial leads were better for detecting discordant APD alternans (8.0 ± 2.9 µV and 12.8 ± 4.52 µV, P = 0.02). MTWA is a potent technique to detect subtle and isolated intracardiac APD alternans that is artificially induced by alternating pacing. In the same model, discordant activation alternans can only be discriminated from concordant when using a quantifying approach of MTWA analysis. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.