Radionuclide evaluation of left ventricular function with nonimaging probes.

PubMed

Wexler, J P; Blaufox, M D

1979-10-01

Portable nonimaging probes have been developed that can evaluate left ventricular function using radionuclide techniques. Two modes of data acquisition are possible with these probe systems, first-pass and gated. Precordial radiocardiograms obtained after a bolus injection can be used to determine cardiac output, pulmonary transit time, pulmonary blood volume, left ventricle ejection fraction, and left-to-right shunts. Gated techniques can be used to determine left ventricular ejection fraction and sytolic time intervals. Probe-determined indices of left ventricular function agree excellently with comparable measurements determined by conventional camera-computer methods as well as by invasive techniques. These have begun to be used in a preliminary manner in a variety of clinical problems associated with left ventricular dysfunction. This review discusses the types of probe systems available, the methods used in positioning them, and details the specifics of their data acquisition and processing capacity. The major criticisms of probe methods are that they are nonimaging and that they measure global rather than regional left ventricular function. In spite of these criticisms, probe systems, because of their portability, high sensitivity, and relatively low cost are useful supplements to conventional camera-computer systems for the measurement of parameters of left ventricular performance using radionuclide techniques.

Is Doppler tissue velocity during early left ventricular filling preload independent?

NASA Technical Reports Server (NTRS)

Yalcin, F.; Kaftan, A.; Muderrisoglu, H.; Korkmaz, M. E.; Flachskampf, F.; Garcia, M.; Thomas, J. D.

2002-01-01

BACKGROUND: Transmitral Doppler flow indices are used to evaluate diastolic function. Recently, velocities measured by Doppler tissue imaging have been used as an index of left ventricular relaxation. OBJECTIVE: To determine whether Doppler tissue velocities are influenced by alterations in preload. METHODS: Left ventricular preload was altered in 17 patients (all men, mean (SD) age, 49 (8) years) during echocardiographic measurements of left ventricular end diastolic volume, maximum left atrial area, peak early Doppler filling velocity, and left ventricular myocardial velocities during early filling. Preload altering manoeuvres included Trendelenberg (stage 1), reverse Trendelenberg (stage 2), and amyl nitrate (stage 3). Systolic blood pressure was measured at each stage. RESULTS: In comparison with baseline, left ventricular end diastolic volume (p = 0.001), left atrial area (p = 0.003), peak early mitral Doppler filling velocity (p = 0.01), and systolic blood pressures (p = 0.001) were all changed by preload altering manoeuvres. Only left ventricular myocardial velocity during early filling remained unchanged by these manoeuvres. CONCLUSIONS: In contrast to standard transmitral Doppler filling indices, Doppler tissue early diastolic velocities are not significantly affected by physiological manoeuvres that alter preload. Thus Doppler tissue velocities during early left ventricular diastole may provide a better index of diastolic function in cardiac patients by providing a preload independent assessment of left ventricular filling.

Cardiovascular magnetic resonance of cardiac function and myocardial mass in preterm infants: a preliminary study of the impact of patent ductus arteriosus

PubMed Central

2014-01-01

Background Many pathologies seen in the preterm population are associated with abnormal blood supply, yet robust evaluation of preterm cardiac function is scarce and consequently normative ranges in this population are limited. The aim of this study was to quantify and validate left ventricular dimension and function in preterm infants using cardiovascular magnetic resonance (CMR). An initial investigation of the impact of the common congenital defect patent ductus arteriosus (PDA) was then carried out. Methods Steady State Free Procession short axis stacks were acquired. Normative ranges of left ventricular end diastolic volume (EDV), stroke volume (SV), left ventricular output (LVO), ejection fraction (EF), left ventricular (LV) mass, wall thickness and fractional thickening were determined in “healthy” (control) neonates. Left ventricular parameters were then investigated in PDA infants. Unpaired student t-tests compared the 2 groups. Multiple linear regression analysis assessed impact of shunt volume in PDA infants, p-value ≤ 0.05 being significant. Results 29 control infants median (range) corrected gestational age at scan 34+6(31+1-39+3) weeks were scanned. EDV, SV, LVO, LV mass normalized by weight and EF were shown to decrease with increasing corrected gestational age (cGA) in controls. In 16 PDA infants (cGA 30+3(27+3-36+1) weeks) left ventricular dimension and output were significantly increased, yet there was no significant difference in ejection fraction and fractional thickening between the two groups. A significant association between shunt volume and increased left ventricular mass correcting for postnatal age and corrected gestational age existed. Conclusion CMR assessment of left ventricular function has been validated in neonates, providing more robust normative ranges of left ventricular dimension and function in this population. Initial investigation of PDA infants would suggest that function is relatively maintained. PMID:25160730

The overloaded right heart and ventricular interdependence.

PubMed

Naeije, Robert; Badagliacca, Roberto

2017-10-01

The right and the left ventricle are interdependent as both structures are nested within the pericardium, have the septum in common and are encircled with common myocardial fibres. Therefore, right ventricular volume or pressure overloading affects left ventricular function, and this in turn may affect the right ventricle. In normal subjects at rest, right ventricular function has negligible interaction with left ventricular function. However, the right ventricle contributes significantly to the normal cardiac output response to exercise. In patients with right ventricular volume overload without pulmonary hypertension, left ventricular diastolic compliance is decreased and ejection fraction depressed but without intrinsic alteration in contractility. In patients with right ventricular pressure overload, left ventricular compliance is decreased with initial preservation of left ventricular ejection fraction, but with eventual left ventricular atrophic remodelling and altered systolic function. Breathing affects ventricular interdependence, in healthy subjects during exercise and in patients with lung diseases and altered respiratory system mechanics. Inspiration increases right ventricular volumes and decreases left ventricular volumes. Expiration decreases both right and left ventricular volumes. The presence of an intact pericardium enhances ventricular diastolic interdependence but has negligible effect on ventricular systolic interdependence. On the other hand, systolic interdependence is enhanced by a stiff right ventricular free wall, and decreased by a stiff septum. Recent imaging studies have shown that both diastolic and systolic ventricular interactions are negatively affected by right ventricular regional inhomogeneity and prolongation of contraction, which occur along with an increase in pulmonary artery pressure. The clinical relevance of these observations is being explored. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Three-dimensional Echocardiography of Right Ventricular Function Correlates with Severity of Pediatric Pulmonary Hypertension.

PubMed

Jone, Pei-Ni; Patel, Sonali S; Cassidy, Courtney; Ivy, David Dunbar

2016-12-01

Right ventricular function and biomarkers of B-type natriuretic peptide (BNP) and N-Terminal pro-BNP (NT pro-BNP) are used to determine the severity of right ventricular failure and outcomes from pulmonary hypertension. Real-time three-dimensional echocardiography (3DE) is a novel quantitative measure of the right ventricle and decreases the geometric assumptions from conventional two-dimensional echocardiography (2DE). We correlated right ventricular functional measures using 2DE and single-beat 3DE with biomarkers and hemodynamics to determine the severity of pediatric pulmonary hypertension. We retrospectively evaluated 35 patients (mean age 12.67 ± 5.78 years) with established pulmonary hypertension who had echocardiograms and biomarkers on the same day. Ten out of 35 patients had hemodynamic evaluation within 3 days. 2DE evaluation included tricuspid annular plane systolic excursion (TAPSE), right ventricular myocardial performance index from tissue Doppler imaging (RV TDI MPI), and right ventricular fractional area change (FAC). Three-dimensional echocardiography evaluation included right ventricular ejection fraction (EF), end-systolic volume, and end-diastolic volume. The quality of the 3DE was graded as good, fair, or poor. Pearson correlation coefficients were utilized to evaluate between biomarkers and echocardiographic parameters and between hemodynamics and echocardiography. Three-dimensional echocardiography and FAC correlated significantly with BNP and NT pro-BNP. TAPSE and RV TDI MPI did not correlate significantly with biomarkers. 3D right ventricular EF correlated significantly with hemodynamics. Two-dimensional echocardiography did not correlate with hemodynamics. Single-beat 3DE is a noninvasive, feasible tool in the quantification of right ventricular function and maybe more accurate than conventional 2DE in evaluating severity of pulmonary hypertension. © 2016 Wiley Periodicals, Inc.

Ventricular efficiency in pregnant women with congenital heart disease.

PubMed

Muneuchi, Jun; Yamasaki, Keiko; Watanabe, Mamie; Fukumitsu, Azusa; Kawakami, Takeshi; Nakahara, Hiromasa; Joo, Kunitaka

2018-06-15

Pregnant women with congenital heart disease (CHD) are at risk of cardiovascular events during pregnancy as well as postpartum. The aim of our study is to address the feasibility of echocardiography-derived ventricular-arterial coupling during pregnancy and postpartum among women with CHD. In 31 pregnant women with CHD, we performed serial echocardiography at the first and third trimesters, early and late postpartum. The indices of contractility (single-beat determined end-systolic elastance, Ees ab ) and afterload (effective arterial elastance, Ea) were approximated on the basis of the systemic blood pressure and systemic ventricular volume. The ratio of stroke work and pressure-volume area (SW/PVA) representing ventricular efficiency was also calculated. Age at the delivery was 28 (24-31) years. ZAHARA score was 0.75 (0.75-1.50). Gestational age and birth weight of newborns were 38 (37-39) weeks and 2.73 (2.42-2.92) kg, respectively. Heart rate, systemic ventricular end-diastolic volume and stroke volume significantly increased from the first trimester to the third trimester and reversed postpartum to the values of the first trimester. Ees ab and Ea significantly decreased from the first trimester to the third trimester (Ees ab ; 4.90 [2.86-7.14] vs 3.41 [2.53-4.61] mm Hg/ml, p = 0.0001, Ea; 2.83 [1.74-3.30] vs 2.18 [1.67-2.68] mm Hg/ml, p = 0.0012), and reversed early postpartum parallelly. Ejection fraction and SW/PVA remained unchanged throughout pregnancy and postpartum. Echocardiography-derived ventricular-arterial coupling is feasible to understand ventricular function in pregnant women with CHD. Copyright © 2018 Elsevier B.V. All rights reserved.

Left ventricular pressure and volume data acquisition and analysis using LabVIEW.

PubMed

Cassidy, S C; Teitel, D F

1997-03-01

To automate analysis of left ventricular pressure-volume data, we used LabVIEW to create applications that digitize and display data recorded from conductance and manometric catheters. Applications separate data into cardiac cycles, calculate parallel conductance, and calculate indices of left ventricular function, including end-systolic elastance, preload-recruitable stroke work, stroke volume, ejection fraction, stroke work, maximum and minimum derivative of ventricular pressure, heart rate, indices of relaxation, peak filling rate, and ventricular chamber stiffness. Pressure-volume loops can be graphically displayed. These analyses are exported to a text-file. These applications have simplified and automated the process of evaluating ventricular function.

Diastolic viscous properties of the intact canine left ventricle.

PubMed

Nikolic, S D; Tamura, K; Tamura, T; Dahm, M; Frater, R W; Yellin, E L

1990-08-01

The viscoelastic model of the ventricle predicts that the rate of change of volume (strain rate) is a determinant of the instantaneous pressure in the ventricle during diastole. Because relaxation is not complete before the onset of filling, one cannot distinguish the individual effects of relaxation and viscosity unless the passive and active components that determine the ventricular pressure are separated. To overcome this problem, we used the method of ventricular volume clamping to compare the pressures in the fully relaxed ventricle at a given volume at zero strain rate (static pressure) and high strain rate (dynamic pressure). Six open-chest, fentanyl-anesthetized dogs were instrumented with micromanometers and an electronically controlled mitral valve occluder in series with the electromagnetic flow probe. We reasoned as follows: If there were significant viscosity, then the dynamic pressure would be higher than the static pressure. The static pressure was measured when the ventricle was completely relaxed following a mitral valve occlusion after an arbitrary filling volume had been achieved. The dynamic pressure was determined by delaying the onset of filling until relaxation was complete and then measuring the pressure at the same volume that was achieved when the static pressure was measured. In 19 different hemodynamic situations, the dynamic and static pressures were identical (mean difference, 0.1 +/- 0.8 mm Hg), indicating that in the passive ventricle viscoelastic effects are insignificant and do not contribute to the left ventricular diastolic pressure under normal filling rates.

Importance of Non-invasive Right and Left Ventricular Variables on Exercise Capacity in Patients with Tetralogy of Fallot Hemodynamics.

PubMed

Meierhofer, Christian; Tavakkoli, Timon; Kühn, Andreas; Ulm, Kurt; Hager, Alfred; Müller, Jan; Martinoff, Stefan; Ewert, Peter; Stern, Heiko

2017-12-01

Good quality of life correlates with a good exercise capacity in daily life in patients with tetralogy of Fallot (ToF). Patients after correction of ToF usually develop residual defects such as pulmonary regurgitation or stenosis of variable severity. However, the importance of different hemodynamic parameters and their impact on exercise capacity is unclear. We investigated several hemodynamic parameters measured by cardiovascular magnetic resonance (CMR) and echocardiography and evaluated which parameter has the most pronounced effect on maximal exercise capacity determined by cardiopulmonary exercise testing (CPET). 132 patients with ToF-like hemodynamics were tested during routine follow-up with CMR, echocardiography and CPET. Right and left ventricular volume data, ventricular ejection fraction and pulmonary regurgitation were evaluated by CMR. Echocardiographic pressure gradients in the right ventricular outflow tract and through the tricuspid valve were measured. All data were classified and correlated with the results of CPET evaluations of these patients. The analysis was performed using the Random Forest model. In this way, we calculated the importance of the different hemodynamic variables related to the maximal oxygen uptake in CPET (VO 2 %predicted). Right ventricular pressure showed the most important influence on maximal oxygen uptake, whereas pulmonary regurgitation and right ventricular enddiastolic volume were not important hemodynamic variables to predict maximal oxygen uptake in CPET. Maximal exercise capacity was only very weakly influenced by right ventricular enddiastolic volume and not at all by pulmonary regurgitation in patients with ToF. The variable with the most pronounced influence was the right ventricular pressure.

Dependence of Intramyocardial Pressure and Coronary Flow on Ventricular Loading and Contractility: A Model Study

PubMed Central

Borsje, Petra; Arts, Theo; van De Vosse, Frans N.

2006-01-01

The phasic coronary arterial inflow during the normal cardiac cycle has been explained with simple (waterfall, intramyocardial pump) models, emphasizing the role of ventricular pressure. To explain changes in isovolumic and low afterload beats, these models were extended with the effect of three-dimensional wall stress, nonlinear characteristics of the coronary bed, and extravascular fluid exchange. With the associated increase in the number of model parameters, a detailed parameter sensitivity analysis has become difficult. Therefore we investigated the primary relations between ventricular pressure and volume, wall stress, intramyocardial pressure and coronary blood flow, with a mathematical model with a limited number of parameters. The model replicates several experimental observations: the phasic character of coronary inflow is virtually independent of maximum ventricular pressure, the amplitude of the coronary flow signal varies about proportionally with cardiac contractility, and intramyocardial pressure in the ventricular wall may exceed ventricular pressure. A parameter sensitivity analysis shows that the normalized amplitude of coronary inflow is mainly determined by contractility, reflected in ventricular pressure and, at low ventricular volumes, radial wall stress. Normalized flow amplitude is less sensitive to myocardial coronary compliance and resistance, and to the relation between active fiber stress, time, and sarcomere shortening velocity. PMID:17048105

Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure.

PubMed

Maier, Joscha; Sawall, Stefan; Kachelrieß, Marc

2014-05-01

Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levels from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.

Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure

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

Maier, Joscha, E-mail: joscha.maier@dkfz.de; Sawall, Stefan; Kachelrieß, Marc

2014-05-15

Purpose: Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levelsmore » from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. Methods: Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. Results: Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. Conclusions: LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.« less

Continuous Positive Airway Pressure Therapy Reduces Right Ventricular Volume in Patients with Obstructive Sleep Apnea: A Cardiovascular Magnetic Resonance Study

PubMed Central

Magalang, Ulysses J.; Richards, Kathryn; McCarthy, Beth; Fathala, Ahmed; Khan, Meena; Parinandi, Narasimham; Raman, Subha V.

2009-01-01

Study Objectives. There are few data on the effects of continuous positive airway pressure (CPAP) therapy on the structural and functional characteristics of the right heart in patients with obstructive sleep apnea (OSA). We sought to leverage the advantages of cardiac magnetic resonance imaging (CMR) and hypothesized that CPAP treatment would improve right ventricular (RV) function in a group of patients with OSA who were free of other comorbid conditions. Methods. Patients with severe (apnea-hypopnea index ≥ 30/h) untreated OSA were prospectively enrolled. CMR included 3-dimensional measurement of biventricular size and function, and rest/stress myocardial perfusion and was performed at baseline and after 3 months of CPAP therapy. Results. Fifteen patients with mild to moderate desaturation were enrolled; 2 could not undergo CMR due to claustrophobia and obesity. There were significant decreases in the Epworth Sleepiness Scale score (p < 0.0001) and RV end-systolic and RV end-diastolic volumes (p < 0.05) with CPAP. There was a trend toward improvement in RV ejection fraction, but the improvement did not reach statistical significance. Other measures such as left ventricular volumes, left ventricular ejection fraction, myocardial perfusion reserve index, and thickness of the interventricular septum and ventricular free wall did not change significantly. Conclusions: This preliminary study found that CPAP treatment decreases RV volumes in patients with severe OSA who are otherwise healthy. CMR offers a novel technique to determine the effects of CPAP on ventricular structure and function in patients with OSA. A randomized controlled study is needed to confirm the results of our study. Citation: Magalang UJ; Richards K; McCarthy B; Fathala A; Khan M; Parinandi N; Raman SV. Continuous positive airway pressure therapy reduces right ventricular volume in patients with obstructive sleep apnea: a cardiovascular magnetic resonance study. J Clin Sleep Med 2009;5(2):110-114. PMID:19968042

Investigation of membranous ventricular septal defect complicated with tricuspid regurgitation in ventricular septal defect occlusion

PubMed Central

LIU, SHU-PING; LI, LI; YAO, KE-CHUN; WANG, NA; WANG, JIAN-CHANG

2013-01-01

This study aimed to explore the mechanism of membranous ventricular septal defect complicated with tricuspid regurgitation and the significance of ventricular septal defect occlusion by echocardiography. A total of 43 patients with membranous ventricular septal defect complicated with tricuspid regurgitation were observed by echocardiography and the changes in length, area and volume of tricuspid regurgitation prior to and following ventricular septal defect occlusion were measured. There were four different mechanisms of membranous ventricular septal defect complicated with tricuspid regurgitation. The various indices of tricuspid regurgitation volume were significantly reduced following occlusion. Ventricular septal defect occlusion significantly reduces tricuspid regurgitation volume complicated with membranous ventricular septal defect and echocardiography is an ideal method to detect these changes. PMID:23404058

Acute decrease of left ventricular mechanical dyssynchrony and improvement of contractile state and energy efficiency after left ventricular restoration.

PubMed

Schreuder, Jan J; Castiglioni, Alessandro; Maisano, Francesco; Steendijk, Paul; Donelli, Andrea; Baan, Jan; Alfieri, Ottavio

2005-01-01

Surgical left ventricular restoration by means of endoventricular patch aneurysmectomy in patients with postinfarction aneurysm should result in acute improved left ventricular performance by decreasing mechanical dyssynchrony and increasing energy efficiency. Nine patients with left ventricular postinfarction aneurysm were studied intraoperatively before and after ventricular restoration with a conductance volume catheter to analyze pressure-volume relationships, energy efficiency, and mechanical dyssynchrony. The end-systolic elastance was used as a load-independent index of contractile state. Left ventricular energy efficiency was calculated from stroke work and total pressure-volume area. Segmental volume changes perpendicular to the long axis were used to calculate mechanical dyssynchrony. Statistical analysis was performed with the paired t test and least-squares linear regression. Endoventricular patch aneurysmectomy reduced end-diastolic volume by 37% (P < .001), with unchanged stroke volume. Systolic function improved, as derived from increased +dP/dt(max), by 42% (P < .03), peak ejection rate by 28% (P < .02), and ejection fraction by 16% (P < .0002). Early diastolic function improved, as shown by reduction of -dP/dt(max) by 34% (P < .006) and shortened tau by 30% (P < .001). Left ventricular end-systolic elastance increased from 1.2 +/- 0.6 to 2.2 +/- 1 mm Hg/mL (P < .001). Left ventricular energy efficiency increased by 36% (P < .002). Left ventricular mechanical dyssynchrony decreased during systole by 33% (P < .001) and during diastole by 20% (P < .005). Left ventricular restoration induced acute improvements in contractile state, energy efficiency, and relaxation, together with a decrease in left ventricular mechanical dyssynchrony.

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.

Troponin elevation in severe sepsis and septic shock: the role of left ventricular diastolic dysfunction and right ventricular dilatation*.

PubMed

Landesberg, Giora; Jaffe, Allan S; Gilon, Dan; Levin, Phillip D; Goodman, Sergey; Abu-Baih, Abed; Beeri, Ronen; Weissman, Charles; Sprung, Charles L; Landesberg, Amir

2014-04-01

Serum troponin concentrations predict mortality in almost every clinical setting they have been examined, including sepsis. However, the causes for troponin elevations in sepsis are poorly understood. We hypothesized that detailed investigation of myocardial dysfunction by echocardiography can provide insight into the possible causes of troponin elevation and its association with mortality in sepsis. Prospective, analytic cohort study. Tertiary academic institute. A cohort of ICU patients with severe sepsis or septic shock. Advanced echocardiography using global strain, strain-rate imaging and 3D left and right ventricular volume analyses in addition to the standard echocardiography, and concomitant high-sensitivity troponin-T measurement in patients with severe sepsis or septic shock. Two hundred twenty-five echocardiograms and concomitant high-sensitivity troponin-T measurements were performed in a cohort of 106 patients within the first days of severe sepsis or septic shock (2.1 ± 1.4 measurements/patient). Combining echocardiographic and clinical variables, left ventricular diastolic dysfunction defined as increased mitral E-to-strain-rate e'-wave ratio, right ventricular dilatation (increased right ventricular end-systolic volume index), high Acute Physiology and Chronic Health Evaluation-II score, and low glomerular filtration rate best correlated with elevated log-transformed concomitant high-sensitivity troponin-T concentrations (mixed linear model: t = 3.8, 3.3, 2.8, and -2.1 and p = 0.001, 0.0002, 0.006, and 0.007, respectively). Left ventricular systolic dysfunction determined by reduced strain-rate s'-wave or low ejection fraction did not significantly correlate with log(concomitant high-sensitivity troponin-T). Forty-one patients (39%) died in-hospital. Right ventricular end-systolic volume index and left ventricular strain-rate e'-wave predicted in-hospital mortality, independent of Acute Physiology and Chronic Health Evaluation-II score (logistic regression: Wald = 8.4, 6.6, and 9.8 and p = 0.004, 0.010, and 0.001, respectively). Concomitant high-sensitivity troponin-T predicted mortality in univariate analysis (Wald = 8.4; p = 0.004), but not when combined with right ventricular end-systolic volume index and strain-rate e'-wave in the multivariate analysis (Wald = 2.3, 4.6, and 6.2 and p = 0.13, 0.032, and 0.012, respectively). Left ventricular diastolic dysfunction and right ventricular dilatation are the echocardiographic variables correlating best with concomitant high-sensitivity troponin-T concentrations. Left ventricular diastolic and right ventricular systolic dysfunction seem to explain the association of troponin with mortality in severe sepsis and septic shock.

Validation of real-time three-dimensional echocardiography for quantifying left ventricular volumes in the presence of a left ventricular aneurysm: in vitro and in vivo studies

NASA Technical Reports Server (NTRS)

Qin, J. X.; Jones, M.; Shiota, T.; Greenberg, N. L.; Tsujino, H.; Firstenberg, M. S.; Gupta, P. C.; Zetts, A. D.; Xu, Y.; Ping Sun, J.;

Right and Left Ventricular Function and Mass in Male Elite Master Athletes: A Controlled Contrast-Enhanced Cardiovascular Magnetic Resonance Study.

PubMed

Bohm, Philipp; Schneider, Günther; Linneweber, Lutz; Rentzsch, Axel; Krämer, Nadine; Abdul-Khaliq, Hashim; Kindermann, Wilfried; Meyer, Tim; Scharhag, Jürgen

2016-05-17

It is under debate whether the cumulative effects of intensive endurance exercise induce chronic cardiac damage, mainly involving the right heart. The aim of this study was to examine the cardiac structure and function in long-term elite master endurance athletes with special focus on the right ventricle by contrast-enhanced cardiovascular magnetic resonance. Thirty-three healthy white competitive elite male master endurance athletes (age range, 30-60 years) with a training history of 29±8 years, and 33 white control subjects pair-matched for age, height, and weight underwent cardiopulmonary exercise testing, echocardiography including tissue-Doppler imaging and speckle tracking, and cardiovascular magnetic resonance. Indexed left ventricular mass and right ventricular mass (left ventricular mass/body surface area, 96±13 and 62±10 g/m(2); P<0.001; right ventricular mass/body surface area, 36±7 and 24±5 g/m(2); P<0.001) and indexed left ventricular end-diastolic volume and right ventricular end-diastolic volume (left ventricular end-diastolic volume/body surface area, 104±13 and 69±18 mL/m(2); P<0.001; right ventricular end-diastolic volume/body surface area, 110±22 and 66±16 mL/m(2); P<0.001) were significantly increased in athletes in comparison with control subjects. Right ventricular ejection fraction did not differ between athletes and control subjects (52±8 and 54±6%; P=0.26). Pathological late enhancement was detected in 1 athlete. No correlations were found for left ventricular and right ventricular volumes and ejection fraction with N-terminal pro-brain natriuretic peptide, and high-sensitive troponin was negative in all subjects. Based on our results, chronic right ventricular damage in elite endurance master athletes with lifelong high training volumes seems to be unlikely. Thus, the hypothesis of an exercise-induced arrhythmogenic right ventricular cardiomyopathy has to be questioned. © 2016 American Heart Association, Inc.

Experimental study of quantitative assessment of left ventricular mass with contrast enhanced real-time three-dimensional echocardiography.

PubMed

Zhuang, Lei; Wang, Xin-Fang; Xie, Ming-Xing; Chen, Li-Xin; Fei, Hong-Wen; Yang, Ying; Wang, Jing; Huang, Run-Qing; Chen, Ou-Di; Wang, Liang-Yu

2004-01-01

To evaluate the feasibility and accuracy of measurement of left ventricular mass with intravenous contrast enhanced real-time three-dimensional (RT3D) echocardiography in the experimental setting. RT3D echocardiography was performed in 13 open-chest mongrel dogs before and after intravenous infusion of a perfluorocarbon contrast agent. Left ventricular myocardium volume was measured according to the apical four-plane method provided by TomTec 4D cardio-View RT1.0 software, then the left ventricular mass was calculated as the myocardial volume multiplied by the relative density of myocardium. Correlative analysis and paired t-test were performed between left ventricular mass obtained from RT3D echocardiography and the anatomic measurements. Anatomic measurement of total left ventricular mass was 55.6 +/- 9.3 g, whereas RT3D echocardiographic calculation of left ventricular mass before and after intravenous perfluorocarbon contrast agent was 57.5 +/- 11.4 and 55.5 +/- 9.3 g, respectively. A significant correlation was observed between the RT3D echocardiographic estimates of total left ventricular mass and the corresponding anatomic measurements (r = 0.95). A strong correlation was found between RT3D echocardiographic estimates of left ventricular mass with perfluorocarbon contrast and the anatomic results (r = 0.99). Analysis of intraobserver and interobserver variability showed strong indexes of agreement in the measurement of left ventricular mass with pre and post-contrast RT3D echocardiography. Measurements of left ventricular mass derived from RT3D echocardiography with and without intravenous contrast showed a significant correlation with the anatomic results. Contrast enhanced RT3D echocardiography permitted better visualization of the endocardial border, which would provide a more accurate and reliable means of determining left ventricular myocardial mass in the experimental setting.

Correlations between ventricular enlargement and gray and white matter volumes of cortex, thalamus, striatum, and internal capsule in schizophrenia.

PubMed

Horga, Guillermo; Bernacer, Javier; Dusi, Nicola; Entis, Jonathan; Chu, Kingwai; Hazlett, Erin A; Haznedar, M Mehmet; Kemether, Eileen; Byne, William; Buchsbaum, Monte S

2011-10-01

Ventricular enlargement is one of the most consistent abnormal structural brain findings in schizophrenia and has been used to infer brain shrinkage. However, whether ventricular enlargement is related to local overlying cortex and/or adjacent subcortical structures or whether it is related to brain volume change globally has not been assessed. We systematically assessed interrelations of ventricular volumes with gray and white matter volumes of 40 Brodmann areas (BAs), the thalamus and its medial dorsal nucleus and pulvinar, the internal capsule, caudate and putamen. We acquired structural MRI ( patients with schizophrenia (n = 64) and healthy controls (n = 56)) and diffusion tensor fractional anisotropy (FA) (untreated schizophrenia n = 19, controls n = 32). Volumes were assessed by manual tracing of central structures and a semi-automated parcellation of BAs. Patients with schizophrenia had increased ventricular size associated with decreased cortical gray matter volumes widely across the brain; a similar but less pronounced pattern was seen in normal controls; local correlations (e.g. temporal horn with temporal lobe volume) were not appreciably higher than non-local correlations (e.g. temporal horn with prefrontal volume). White matter regions adjacent to the ventricles similarly did not reveal strong regional relationships. FA and center of mass of the anterior limb of the internal capsule also appeared differentially influenced by ventricular volume but findings were similarly not regional. Taken together, these findings indicate that ventricular enlargement is globally interrelated with gray matter volume diminution but not directly correlated with volume loss in the immediately adjacent caudate, putamen, or internal capsule.

Non invasive evaluation of cardiomechanics in patients undergoing MitrClip procedure

PubMed Central

2013-01-01

Background In the last recent years a new percutaneous procedure, the MitraClip, has been validated for the treatment of mitral regurgitation. MitraClip procedure is a promising alternative for patients unsuitable for surgery as it reduces the risk of death related to surgery ensuring a similar result. Few data are present in literature about the variation of hemodynamic parameters and ventricular coupling after Mitraclip implantation. Methods Hemodynamic data of 18 patients enrolled for MitraClip procedure were retrospectively reviewed and analyzed. Echocardiographic measurements were obtained the day before the procedure (T0) and 21 ± 3 days after the procedure (T1), including evaluation of Ejection Fraction, mitral valve regurgitation severity and mechanism, forward Stroke Volume, left atrial volume, estimated systolic pulmonary pressure, non invasive echocardiographic estimation of single beat ventricular elastance (Es(sb)), arterial elastance (Ea) measured as systolic pressure • 0.9/ Stroke Volume, ventricular arterial coupling (Ea/Es(sb) ratio). Data were expressed as median and interquartile range. Measures obtained before and after the procedure were compared using Wilcoxon non parametric test for paired samples. Results Mitraclip procedure was effective in reducing regurgitation. We observed an amelioration of echocardiographic parameters with a reduction of estimated systolic pulmonary pressure (45 to 37,5 p = 0,0002) and left atrial volume (110 to 93 p = 0,0001). Despite a few cases decreasing in ejection fraction (37 to 35 p = 0,035), the maintained ventricular arterial coupling after the procedure (P = 0,67) was associated with an increasing in forward stroke volume (60,3 to 78 p = 0,05). Conclusion MitraClip is effective in reducing mitral valve regurgitation and determines an amelioration of hemodynamic parameters with preservation of ventricular arterial coupling. PMID:23642140

Studies on deflection area vectors of QRS and T and ventricular gradient in right ventricular hypertrophy.

PubMed

Kawaguchi, Y

1985-04-01

QRS deflection area vector (Aqrs), T deflection area vector (At) and ventricular gradient (G) in right ventricular hypertrophy were studied in 53 subjects divided on the basis of cardiac catheterization data into four subgroups; normal controls, mild MS group, right ventricular pressure overload group and right ventricular volume overload group. Aqrs, At and G of the four subgroups were calculated using a microcomputer and compared. Aqrs in right ventricular pressure overload group and volume overload group was shifted to the right and slightly anteriorly from that in normal control group. At in right ventricular pressure overload group and volume overload group was shifted slightly upwards and significantly posteriorly from that in the normal control and mild MS groups. G in right ventricular pressure overload group and volume overload group was shifted to the right and significantly posteriorly from that in normal control and mild MS groups. Using multivariative analysis, we developed criteria for diagnosing right ventricular hypertrophy with At: 0.059At(Z) - 0.0145 [At] - 0.2608 less than or equal to 0. Application of this criteria achieved 82.4% (28 of 34) sensitivity in the patients with right ventricular hypertrophy and 90.9% (10 of 11) specificity in the normal control subjects.

Dissociation of end systole from end ejection in patients with long-term mitral regurgitation.

PubMed

Brickner, M E; Starling, M R

1990-04-01

To determine whether left ventricular (LV) end systole and end ejection uncouple in patients with long-term mitral regurgitation, 59 patients (22 control patients with atypical chest pain, 21 patients with aortic regurgitation, and 16 patients with mitral regurgitation) were studied with micromanometer LV catheters and radionuclide angiograms. End systole was defined as the time of occurrence (Tmax) of the maximum time-varying elastance (Emax), and end ejection was defined as the time of occurrence of minimum ventricular volume (minV) and zero systolic flow as approximated by the aortic dicrotic notch (Aodi). The temporal relation between end systole and end ejection in the control patients was Tmax (331 +/- 42 [SD] msec), minV (336 +/- 36 msec), and then, zero systolic flow (355 +/- 23 msec). This temporal relation was maintained in the patients with aortic regurgitation. In contrast, in the patients with mitral regurgitation, the temporal relation was Tmax (266 +/- 49 msec), zero systolic flow (310 +/- 37 msec, p less than 0.01 vs. Tmax), and then, minV (355 +/- 37 msec, p less than 0.001 vs. Tmax and p less than 0.01 vs. Aodi). Additionally, the average Tmax occurred earlier in the patients with mitral regurgitation than in the control patients and patients with aortic regurgitation (p less than 0.01, for both), whereas the average time to minimum ventricular volume was similar in all three patient groups. Moreover, the average time to zero systolic flow also occurred earlier in the patients with mitral regurgitation than in the control patients (p less than 0.01) and patients with aortic regurgitation (p less than 0.05). Because of the dissociation of end systole from minimum ventricular volume in the patients with mitral regurgitation, the end-ejection pressure-volume relations calculated at minimum ventricular volume did not correlate (r = -0.09), whereas those calculated at zero systolic flow did correlate (r = 0.88) with the Emax slope values. We conclude that end ejection, defined as minimum ventricular volume, dissociates from end systole in patients with mitral regurgitation because of the shortened time to LV end systole in association with preservation of the time to LV end ejection due to the low impedance to ejection presented by the left atrium. Therefore, pressure-volume relations calculated at minimum ventricular volume might not be useful for assessing LV chamber performance in some patients with mitral regurgitation.

Effect of valsartan on systemic right ventricular function: a double-blind, randomized, placebo-controlled pilot trial.

PubMed

van der Bom, Teun; Winter, Michiel M; Bouma, Berto J; Groenink, Maarten; Vliegen, Hubert W; Pieper, Petronella G; van Dijk, Arie P J; Sieswerda, Gertjan T; Roos-Hesselink, Jolien W; Zwinderman, Aeilko H; Mulder, Barbara J M

2013-01-22

The role of angiotensin II receptor blockers in patients with a systemic right ventricle has not been elucidated. We conducted a multicenter, double-blind, parallel, randomized controlled trial of angiotensin II receptor blocker valsartan 160 mg twice daily compared with placebo in patients with a systemic right ventricle caused by congenitally or surgically corrected transposition of the great arteries. The primary end point was change in right ventricular ejection fraction during 3-year follow-up, determined by cardiovascular magnetic resonance imaging or, in patients with contraindication for magnetic resonance imaging, multirow detector computed tomography. Secondary end points were change in right ventricular volumes and mass, Vo(2)peak, and quality of life. Primary analyses were performed on an intention-to-treat basis. A total of 88 patients (valsartan, n=44; placebo, n=44) were enrolled in the trial. No serious adverse effects occurred in either group. There was no significant effect of 3-year valsartan therapy on systemic right ventricular ejection fraction (treatment effect, 1.3%; 95% confidence interval, -1.3% to 3.9%; P=0.34), maximum exercise capacity, or quality of life. There was a larger increase in right ventricular end-diastolic volume (15 mL; 95% confidence interval, 3-28 mL; P<0.01) and mass (8 g; 95% confidence interval, 2-14 g; P=0.01) in the placebo group than in the valsartan group. There was no significant treatment effect of valsartan on right ventricular ejection fraction, exercise capacity, or quality of life. Valsartan was associated with a similar frequency of significant clinical events as placebo. Small but significant differences between valsartan and placebo were present for change in right ventricular volumes and mass. URL: http://www.controlled-trials.com. Unique identifier: ISRCTN52352170.

The correlation between pulsatile intracranial pressure and indices of intracranial pressure-volume reserve capacity: results from ventricular infusion testing.

PubMed

Eide, Per Kristian

2016-12-01

OBJECTIVE The objective of this study was to examine how pulsatile and static intracranial pressure (ICP) scores correlate with indices of intracranial pressure-volume reserve capacity, i.e., intracranial elastance (ICE) and intracranial compliance (ICC), as determined during ventricular infusion testing. METHODS All patients undergoing ventricular infusion testing and overnight ICP monitoring during the 6-year period from 2007 to 2012 were included in the study. Clinical data were retrieved from a quality registry, and the ventricular infusion pressure data and ICP scores were retrieved from a pressure database. The ICE and ICC (= 1/ICE) were computed during the infusion phase of the infusion test. RESULTS During the period from 2007 to 2012, 82 patients with possible treatment-dependent hydrocephalus underwent ventricular infusion testing within the department of neurosurgery. The infusion tests revealed a highly significant positive correlation between ICE and the pulsatile ICP scores mean wave amplitude (MWA) and rise-time coefficient (RTC), and the static ICP score mean ICP. The ICE was negatively associated with linear measures of ventricular size. The overnight ICP recordings revealed significantly increased MWA (> 4 mm Hg) and RTC (> 20 mm Hg/sec) values in patients with impaired ICC (< 0.5 ml/mm Hg). CONCLUSIONS In this study cohort, there was a significant positive correlation between pulsatile ICP and ICE measured during ventricular infusion testing. In patients with impaired ICC during infusion testing (ICC < 0.5 ml/mm Hg), overnight ICP recordings showed increased pulsatile ICP (MWA > 4 mm Hg, RTC > 20 mm Hg/sec), but not increased mean ICP (< 10-15 mm Hg). The present data support the assumption that pulsatile ICP (MWA and RTC) may serve as substitute markers of pressure-volume reserve capacity, i.e., ICE and ICC.

A new electric method for non-invasive continuous monitoring of stroke volume and ventricular volume-time curves

PubMed Central

2012-01-01

Background In this paper a new non-invasive, operator-free, continuous ventricular stroke volume monitoring device (Hemodynamic Cardiac Profiler, HCP) is presented, that measures the average stroke volume (SV) for each period of 20 seconds, as well as ventricular volume-time curves for each cardiac cycle, using a new electric method (Ventricular Field Recognition) with six independent electrode pairs distributed over the frontal thoracic skin. In contrast to existing non-invasive electric methods, our method does not use the algorithms of impedance or bioreactance cardiography. Instead, our method is based on specific 2D spatial patterns on the thoracic skin, representing the distribution, over the thorax, of changes in the applied current field caused by cardiac volume changes during the cardiac cycle. Since total heart volume variation during the cardiac cycle is a poor indicator for ventricular stroke volume, our HCP separates atrial filling effects from ventricular filling effects, and retrieves the volume changes of only the ventricles. Methods ex-vivo experiments on a post-mortem human heart have been performed to measure the effects of increasing the blood volume inside the ventricles in isolation, leaving the atrial volume invariant (which can not be done in-vivo). These effects have been measured as a specific 2D pattern of voltage changes on the thoracic skin. Furthermore, a working prototype of the HCP has been developed that uses these ex-vivo results in an algorithm to decompose voltage changes, that were measured in-vivo by the HCP on the thoracic skin of a human volunteer, into an atrial component and a ventricular component, in almost real-time (with a delay of maximally 39 seconds). The HCP prototype has been tested in-vivo on 7 human volunteers, using G-suit inflation and deflation to provoke stroke volume changes, and LVot Doppler as a reference technique. Results The ex-vivo measurements showed that ventricular filling caused a pattern over the thorax quite distinct from that of atrial filling. The in-vivo tests of the HCP with LVot Doppler resulted in a Pearson’s correlation of R = 0.892, and Bland-Altman plotting of SV yielded a mean bias of -1.6 ml and 2SD =14.8 ml. Conclusions The results indicate that the HCP was able to track the changes in ventricular stroke volume reliably. Furthermore, the HCP produced ventricular volume-time curves that were consistent with the literature, and may be a diagnostic tool as well. PMID:22900831

[Measurement of left atrial and ventricular volumes in real-time 3D echocardiography. Validation by nuclear magnetic resonance

NASA Technical Reports Server (NTRS)

Bauer, F.; Shiota, T.; Qin, J. X.; White, R. D.; Thomas, J. D.

2001-01-01

The measurement of the left ventricular ejection fraction is important for the evaluation of cardiomyopathy and depends on the measurement of left ventricular volumes. There are no existing conventional echocardiographic means of measuring the true left atrial and ventricular volumes without mathematical approximations. The aim of this study was to test anew real time 3-dimensional echocardiographic system of calculating left atrial and ventricular volumes in 40 patients after in vitro validation. The volumes of the left atrium and ventricle acquired from real time 3-D echocardiography in the apical view, were calculated in 7 sections parallel to the surface of the probe and compared with atrial (10 patients) and ventricular (30 patients) volumes calculated by nuclear magnetic resonance with the simpson method and with volumes of water in balloons placed in a cistern. Linear regression analysis showed an excellent correlation between the real volume of water in the balloons and volumes given in real time 3-dimensional echocardiography (y = 0.94x + 5.5, r = 0.99, p < 0.001, D = -10 +/- 4.5 ml). A good correlation was observed between real time 3-dimensional echocardiography and nuclear magnetic resonance for the measurement of left atrial and ventricular volumes (y = 0.95x - 10, r = 0.91, p < 0.001, D = -14.8 +/- 19.5 ml and y = 0.87x + 10, r = 0.98, P < 0.001, D = -8.3 +/- 18.7 ml, respectively. The authors conclude that real time three-dimensional echocardiography allows accurate measurement of left heart volumes underlying the clinical potential of this new 3-D method.

Effects of verapamil on left ventricular systolic and diastolic function in patients with hypertrophic cardiomyopathy: pressure-volume analysis with a nonimaging scintillation probe.

PubMed

Bonow, R O; Ostrow, H G; Rosing, D R; Cannon, R O; Lipson, L C; Maron, B J; Kent, K M; Bacharach, S L; Green, M V

1983-11-01

To investigate the effects of verapamil on left ventricular systolic and diastolic function in patients with hypertrophic cardiomyopathy, we studied 14 patients at catheterization with a nonimaging scintillation probe before and after serial intravenous infusions of low-, medium-, and high-dose verapamil (total dose 0.17 to 0.72 mg/kg). Percent change in radionuclide stroke counts after verapamil correlated well with percent change in thermodilution stroke volume (r = .87), and changes in diastolic and systolic counts were used to assess relative changes in left ventricular volumes after verapamil. Verapamil produced dose-related increases in end-diastolic counts (19 +/- 9% increase; p less than .001), end-systolic counts (91 +/- 54% increase; p less than .001), and stroke counts (7 +/- 10% increase; p less than .02). This was associated with a decrease in ejection fraction (83 +/- 8% control, 73 +/- 10% verapamil; p less than .001) and, in the 10 patients with left ventricular outflow tract gradients, a reduction in gradient (62 +/- 27 mm Hg control, 32 +/- 35 mm Hg verapamil; p less than .01). The end-systolic pressure-volume relation was shifted downward and rightward in all patients, suggesting a negative inotropic effect. In 10 patients, left ventricular pressure-volume loops were constructed with simultaneous micromanometer pressure recordings and the radionuclide time-activity curve. In five patients, verapamil shifted the diastolic pressure-volume curve downward and rightward, demonstrating improved pressure-volume relations despite the negative inotropic effect, and also increased the peak rate of rapid diastolic filling. In the other five patients, the diastolic pressure-volume relation was unaltered by verapamil, and increased end-diastolic volumes occurred at higher end-diastolic pressures; in these patients, the peak rate of left ventricular diastolic filling was not changed by verapamil. The negative inotropic effects of intravenous verapamil are potentially beneficial in patients with hypertrophic cardiomyopathy by decreasing left ventricular contractile function and increasing left ventricular volume. Verapamil also enhances left ventricular diastolic filling and improves diastolic pressure-volume relations in some patients despite its negative inotropic effect.

Reduction of ventricular size after shunting for normal pressure hydrocephalus related to CSF dynamics before shunting.

PubMed Central

Tans, J T; Poortvliet, D C

1988-01-01

Reduction of ventricular size was determined by repeated computed tomography in 30 adult patients shunted for normal pressure hydrocephalus (NPH) and related to the pressure-volume index (PVI) and resistance to outflow of cerebrospinal fluid (Rcsf) measured before shunting. Rapid and marked reduction of ventricular size (n = 10) was associated with a significantly lower PVI than slow and moderate to marked (n = 13) or minimal to mild reduction (n = 7). Otherwise no relationship could be found between the reduction of ventricular size and PVI or Rcsf. It is concluded that both rate and magnitude of reduction of ventricular size after shunting for NPH are extremely variable. High brain elasticity seems to be the best predictor of rapid and marked reduction. PMID:3379425

Diastolic function of the nonfilling human left ventricle.

PubMed

Paulus, W J; Vantrimpont, P J; Rousseau, M F

1992-12-01

To investigate an early-diastolic left ventricular suction effect in humans, tip-micromanometer left ventricular pressure recordings were obtained in patients with mitral stenosis at the time of balloon inflations during percutaneous mitral valvuloplasty performed with a self-positioning Inoue balloon, which fits tightly in the mitral orifice. When mitral inflow was impeded in anesthetized dogs, left ventricular pressure decayed to a negative asymptote value. This negative asymptote value was consistent with an early diastolic suction effect. Tip-micromanometer left ventricular pressure recordings were obtained in 23 patients with symptomatic mitral stenosis at the time of balloon inflations during percutaneous mitral valvuloplasty performed with a self-positioning Inoue balloon. The left ventricular diastolic asymptote pressure (P(asy)) was determined in 47 nonfilling beats with a sufficiently long (greater than 200 ms) diastolic time interval (that is, the interval from minimal first derivative of left ventricular pressure to left ventricular end-diastolic pressure) and equaled 2 +/- 3 mm Hg for beats with normal intraventricular conduction and 3 +/- 2 mm Hg for beats with aberrant intraventricular conduction. Left ventricular angiography was performed in five patients during the first inflation of the Inoue balloon at the time of complete balloon expansion. Left ventricular end-diastolic volume of the nonfilling beats averaged 38 +/- 14 ml and was comparable to the left ventricular end-systolic volume (39 +/- 19 ml) measured during baseline angiography before mitral valvuloplasty. Time constants of left ventricular pressure decay were calculated on 21 nonfilling beats with a diastolic time interval greater than 200 ms, normal intraventricular conduction and peak left ventricular pressure greater than 50 mm Hg. Time constants (T0 and TBF) derived from an exponential curve fit with zero asymptote pressure and with a best-fit asymptote pressure were compared with a time constant (T(asy)) derived from an exponential curve fit with the measured diastolic left ventricular asymptote pressure. The value for T(asy) (37 +/- 9 ms) was significantly smaller than that for TBF (68 +/- 28 ms, p less than 0.001) and the value for the measured diastolic left ventricular asymptote pressure (2 +/- 4 mm Hg) was significantly larger than that for the best-fit asymptote pressure (-9 +/- 11 mm Hg, p less than 0.001). T0 (44 +/- 20 ms) was significantly (p less than 0.01) different from TBF but not from T(asy). During balloon inflation of a self-positioning Inoue balloon, left ventricular pressure decayed continuously toward a positive asymptote value and left ventricular cavity volume was comparable to the left ventricular end-systolic volume of filling beats. In these nonfilling beats, the best-fit asymptote pressure was unrelated to the measured asymptote pressure and T0 was a better measure of T(asy) than was TBF. Reduced internal myocardial restoring forces, caused by different extracellular matrix of the human heart, reduced external myocardial restoring forces caused by low coronary perfusion pressure during the balloon inflation and inward motion of the balloon-occluded mitral valve into the left ventricular cavity could explain the failure to observe significant diastolic left ventricular suction in the human heart.

Race differences in ventricular remodeling and function among college football players.

PubMed

Haddad, Francois; Peter, Shanon; Hulme, Olivia; Liang, David; Schnittger, Ingela; Puryear, Josephine; Gomari, Fatemeh A; Finocchiaro, Gherardo; Myers, Jonathan; Froelicher, Victor; Garza, Daniel; Ashley, Euan A

2013-07-01

Athletic training is associated with increases in ventricular mass and volume. Recent studies have shown that left ventricular mass increases proportionally in white athletes with a mass/volume ratio approaching unity. The objective of this study was to compare the proportionality in ventricular remodeling and ventricular function in black versus white National Collegiate Athletic Association Division I football players. From 2008 to 2011, football players at Stanford University underwent cardiovascular screening with a 12-point history and physical examination, electrocardiography, and focused echocardiography. Compared with white players, black players had on average higher left ventricular mass indexes (77 ± 11 vs 71 ± 11 g/m(2), p = 0.009), higher mass/volume ratios (1.18 ± 0.16 vs 1.06 ± 0.09 g/ml, p <0.001), and higher QRS vector magnitudes (3.2 ± 0.7 vs 2.7 ± 0.8, p = 0.002). Black race had an odds ratio of 14 (95% confidence interval 5 to 42, p <0.001) for a mass/volume ratio >1.2. Mass/volume ratio was inversely related to early diastolic tissue Doppler velocity e' (r = -0.50, p <0.001) but not to QRS vector magnitude (r = 0.065, p = 0.034). With regard to systolic indexes, there was no significant difference in the left ventricular ejection fraction, velocity of circumferential shortening, and isovolumic acceleration. In conclusion, black college football players exhibit more concentric ventricular remodeling, lower early diastolic annular velocities, and increased ventricular voltage compared with white players. Ventricular mass increases proportionally to volume in white players but not in black players. Copyright © 2013 Elsevier Inc. All rights reserved.

Validation of gated blood-pool SPECT cardiac measurements tested using a biventricular dynamic physical phantom.

PubMed

De Bondt, Pieter; Nichols, Kenneth; Vandenberghe, Stijn; Segers, Patrick; De Winter, Olivier; Van de Wiele, Christophe; Verdonck, Pascal; Shazad, Arsalan; Shoyeb, Abu H; De Sutter, Johan

2003-06-01

We have developed a biventricular dynamic physical cardiac phantom to test gated blood-pool (GBP) SPECT image-processing algorithms. Such phantoms provide absolute values against which to assess accuracy of both right and left computed ventricular volume and ejection fraction (EF) measurements. Two silicon-rubber chambers driven by 2 piston pumps simulated crescent-shaped right ventricles wrapped partway around ellopsoid left ventricles. Twenty experiments were performed at Ghent University, for which right and left ventricular true volume and EF ranges were 65-275 mL and 55-165 mL and 7%-49% and 12%-69%, respectively. Resulting 64 x 64 simulated GBP SPECT images acquired at 16 frames per R-R interval were sent to Columbia University, where 2 observers analyzed images independently of each other, without knowledge of true values. Algorithms automatically segmented right ventricular activity volumetrically from left ventricular activity. Automated valve planes, midventricular planes, and segmentation regions were presented to observers, who accepted these choices or modified them as necessary. One observer repeated measurements >1 mo later without reference to previous determinations. Linear correlation coefficients (r) of the mean of the 3 GBP SPECT observations versus true values for right and left ventricles were 0.80 and 0.94 for EF and 0.94 and 0.95 for volumes, respectively. Correlations for right and left ventricles were 0.97 and 0.97 for EF and 0.96 and 0.89 for volumes, respectively, for interobserver agreement and 0.97 and 0.98 for EF and 0.96 and 0.90 for volumes, respectively, for intraobserver agreement. No trends were detected, though volumes and right ventricular EFs were significantly higher than true values. Overall, GBP SPECT measurements correlated strongly with true values. The phantom evaluated shows considerable promise for helping to guide algorithm developments for improved GBP SPECT accuracy.

Ventricular distension and diastolic coronary blood flow in the anaesthetized dog.

PubMed

Gattullo, D; Linden, R J; Losano, G; Pagliaro, P; Westerhof, N

1993-01-01

There appears to be no agreement as to whether or not an increase in diastolic left ventricular pressure and/or volume can cause a decrease in diastolic coronary blood flow. We investigated the problem in the anaesthetized dog using a flaccid freely distensible latex balloon inserted into the left ventricle with the animal on extracorporeal circulation and the coronary perfusion pressure constant at about 45 mm Hg. Maximal vasodilatation and suppression of autoregulation in coronary vasculature was obtained by the intracoronary infusion of dipyridamole (10-40 mg/h). Ventricular volume was changed in steps of 10 ml from 10 to 70 ml and back to 10 ml, whilst recording coronary blood flow and left ventricular pressure in the left circumflex coronary artery. Over a range of ventricular volumes from 20 to 50 ml and a concomitant rise in diastolic ventricular pressure to about 20 mm Hg there was no change in the diastolic coronary flow. Only when the ventricular volume was more than two times the control value (i.e. exceeded 50 ml) and left ventricular pressure was more than 20 mm Hg, was there a decrease in coronary flow. During the return of the volume to the control level there was a fall in diastolic flow and ventricular contractility with respect to the values obtained when the volume was increased; these two effects were transient lasting less than 10 min. It was not considered that any of the three models of the coronary circulation, waterfall, intramyocardial pump or varying elastance model could explain our results.(ABSTRACT TRUNCATED AT 250 WORDS)

Myocardial perfusion and left ventricular function indices assessed by gated myocardial perfusion SPECT in methamphetamine abusers.

PubMed

Dadpour, Bita; Dabbagh Kakhki, Vahid R; Afshari, Reza; Dorri-Giv, Masoumeh; Mohajeri, Seyed A R; Ghahremani, Somayeh

2016-12-01

Methamphetamine (MA) is associated with alterations of cardiac structure and function, although it is less known. In this study, we assessed possible abnormality in myocardial perfusion and left ventricular function using gated myocardial perfusion SPECT. Fifteen patients with MA abuse, on the basis of Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) MA dependency determined by Structured Clinical Interview for DSM-IV, underwent 2-day dipyridamole stress/rest Tc-sestamibi gated myocardial perfusion SPECT. An average daily dose of MA use was 0.91±1.1 (0.2-4) g. The duration of MA use was 3.4±2.1 (1-7) years. In visual and semiquantitative analyses, all patients had normal gated myocardial perfusion SPECT, with no perfusion defects. In all gated SPECT images, there was no abnormality in left ventricular wall motion and thickening. All summed stress scores and summed rest scores were below 3. Calculated left ventricular functional indices including the end-diastolic volume, end-systolic volume, and left ventricular ejection fraction were normal. Many cardiac findings because of MA mentioned in previous reports are less likely because of significant epicardial coronary artery stenosis.

Left ventricular function during lower body negative pressure

NASA Technical Reports Server (NTRS)

Ahmad, M.; Blomqvist, C. G.; Mullins, C. B.; Willerson, J. T.

1977-01-01

The response of the human left ventricle to lower body negative pressure (LBNP) and the relation between left ventricular function and hemodynamic response were investigated. Ventricular function curves relating stroke volume to end-diastolic volume were obtained in 12 normal men. Volume data were derived from echocardiographic measurements of left ventricular end-systolic and end-diastolic diameters at rest and during lower body negative pressure (LBNP) at minus 40 mm Hg. End-diastolic volume decreased by 19% and stroke volume by 22%. There were no significant changes in heart rate, arterial blood pressure, or end-systolic volume. Thus, moderate levels of LBNP significantly reduce preload and stroke volume without affecting contractile state. The absence of significant changes in heart rate and arterial blood pressure in the presence of a significant reduction in stroke volume is consistent with an increase in systemic peripheral resistance mediated by low-pressure baroreceptors.

Cardiovascular response to dobutamine stress predicts outcome in severe sepsis and septic shock.

PubMed

Kumar, Anand; Schupp, Elizabeth; Bunnell, Eugene; Ali, Amjad; Milcarek, Barry; Parrillo, Joseph E

2008-01-01

During septic shock, resistance to the haemodynamic effects of catecholamine vasopressors and inotropes is a well-recognised marker of mortality risk. However, the specific cardiovascular or metabolic response elements that are most closely associated with outcome have not been well defined. The objective of this study was to assess cardiovascular and metabolic responses to dobutamine as correlates of outcome in patients with severe sepsis or septic shock. A prospective, non-randomised, non-blinded interventional study of graded dobutamine challenge (0, 5, 10, and 15 mug/kg/min) in adult patients who had undergone pulmonary artery catheterisation within 48 hours of onset of severe sepsis or septic shock (8 survivors/15 non-survivors) was performed. Radionuclide cineangiography during graded infusion was used to determine biventricular ejection fractions at each increment of dobutamine. In univariate analysis, a variety of cardiovascular or haemodynamic and oxygen transport or metabolic variables (at the point of maximum cardiac index response for a given subject) were associated with survival including: increased stroke volume index (p = 0.0003); right ventricular end-diastolic volume index (p = 0.0047); left ventricular stroke work index (p = 0.0054); oxygen delivery index (p = 0.0084); cardiac index (p = 0.0093); systolic blood pressure/left ventricular end-systolic volume index ratio (p = 0.0188); left ventricular ejection fraction (p = 0.0160); venous oxygen content (p = 0.0208); mixed venous oxygen saturation (p = 0.0234); pulse pressure (p = 0.0403); decreased pulmonary artery diastolic pressure (p = 0.0133); systemic vascular resistance index (p = 0.0154); extraction ratio (p = 0.0160); and pulmonary vascular resistance index (p = 0.0390). Increases of stroke volume index of greater than or less than 8.5 mL/m2 were concordant with survival or death in 21 of 23 cases. Multivariate profile construction showed stroke volume index as the dominant discriminating variable for survival with the systolic blood pressure/left ventricular end-systolic volume index ratio alone among all other variables significantly improving the model. Survivors maintain cardiac responsiveness to catecholamine stimulation during septic shock. Survival from severe sepsis or septic shock is associated with increased cardiac performance and contractility indices during dobutamine infusion. Further studies are required to determine whether these parameters are predictive of outcome in a larger severe sepsis/septic shock population.

Clinical determinants and consequences of left ventricular hypertrophy.

PubMed

Messerli, F H

1983-09-26

The left ventricle adapts to an increased afterload such as that produced by arterial hypertension with concentric left ventricular hypertrophy. However, this adaptive process can be modified by a variety of physiologic and pathophysiologic states. Progressive aging, black race, and perhaps disorders with an increased sympathetic outflow seem to accelerate left ventricular hypertrophy. Obesity and other high cardiac output states predominantly produce dilatation of the left ventricle, and their combination with arterial hypertension results in eccentric left ventricular hypertrophy. Similarly, endurance exercise increases left ventricular volume more than wall thickness, whereas isometric exercise produces an increase in wall thickness only. The presence or absence of some physiologic and pathogenetic factors has direct implication on the assessment of what constitutes a "normal" left ventricular structure and function. Left ventricular hypertrophy has been shown to increase ventricular ectopic impulse generation and to put patients at a high risk of sudden death. Moreover, the increase in myocardial mass lowers coronary reserve and enhances cardiac oxygen requirements. Thus, the presence of left ventricular hypertrophy has to be considered as an ominous sign rather than as a benign adaptive process.

Minimally invasive estimation of ventricular dead space volume through use of Frank-Starling curves.

PubMed

Davidson, Shaun; Pretty, Chris; Pironet, Antoine; Desaive, Thomas; Janssen, Nathalie; Lambermont, Bernard; Morimont, Philippe; Chase, J Geoffrey

2017-01-01

This paper develops a means of more easily and less invasively estimating ventricular dead space volume (Vd), an important, but difficult to measure physiological parameter. Vd represents a subject and condition dependent portion of measured ventricular volume that is not actively participating in ventricular function. It is employed in models based on the time varying elastance concept, which see widespread use in haemodynamic studies, and may have direct diagnostic use. The proposed method involves linear extrapolation of a Frank-Starling curve (stroke volume vs end-diastolic volume) and its end-systolic equivalent (stroke volume vs end-systolic volume), developed across normal clinical procedures such as recruitment manoeuvres, to their point of intersection with the y-axis (where stroke volume is 0) to determine Vd. To demonstrate the broad applicability of the method, it was validated across a cohort of six sedated and anaesthetised male Pietrain pigs, encompassing a variety of cardiac states from healthy baseline behaviour to circulatory failure due to septic shock induced by endotoxin infusion. Linear extrapolation of the curves was supported by strong linear correlation coefficients of R = 0.78 and R = 0.80 average for pre- and post- endotoxin infusion respectively, as well as good agreement between the two linearly extrapolated y-intercepts (Vd) for each subject (no more than 7.8% variation). Method validity was further supported by the physiologically reasonable Vd values produced, equivalent to 44.3-53.1% and 49.3-82.6% of baseline end-systolic volume before and after endotoxin infusion respectively. This method has the potential to allow Vd to be estimated without a particularly demanding, specialised protocol in an experimental environment. Further, due to the common use of both mechanical ventilation and recruitment manoeuvres in intensive care, this method, subject to the availability of multi-beat echocardiography, has the potential to allow for estimation of Vd in a clinical environment.

Left ventricular volume analysis as a basic tool to describe cardiac function.

PubMed

Kerkhof, Peter L M; Kuznetsova, Tatiana; Ali, Rania; Handly, Neal

2018-03-01

The heart is often regarded as a compression pump. Therefore, determination of pressure and volume is essential for cardiac function analysis. Traditionally, ventricular performance was described in terms of the Starling curve, i.e., output related to input. This view is based on two variables (namely, stroke volume and end-diastolic volume), often studied in the isolated (i.e., denervated) heart, and has dominated the interpretation of cardiac mechanics over the last century. The ratio of the prevailing coordinates within that paradigm is termed ejection fraction (EF), which is the popular metric routinely used in the clinic. Here we present an insightful alternative approach while describing volume regulation by relating end-systolic volume (ESV) to end-diastolic volume. This route obviates the undesired use of metrics derived from differences or ratios, as employed in previous models. We illustrate basic principles concerning ventricular volume regulation by data obtained from intact animal experiments and collected in healthy humans. Special attention is given to sex-specific differences. The method can be applied to the dynamics of a single heart and to an ensemble of individuals. Group analysis allows for stratification regarding sex, age, medication, and additional clinically relevant covariates. A straightforward procedure derives the relationship between EF and ESV and describes myocardial oxygen consumption in terms of ESV. This representation enhances insight and reduces the impact of the metric EF, in favor of the end-systolic elastance concept advanced 4 decades ago.

Short Communication: Conformal Therapy for Peri-Ventricular Brain Tumors: Is Target Volume Deformation an Issue?

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

Bauman, Glenn; Woodford, Curtis; Yartsev, Slav

2008-04-01

Physiologic variations in ventricular volumes could have important implications for treating patients with peri-ventricular brain tumors, yet no data exist in the literature addressing this issue. Daily megavoltage computed tomography (CT) scans in a patient with neurocytoma receiving fractionated radiation revealed minimal changes, suggesting that margins accounting for ventricular deformation are not necessary.

Three-Dimensional Right Ventricular Strain Versus Volume Quantification in Heart Transplant Recipients in Relation to Pulmonary Artery Pressure.

PubMed

Sade, Leyla Elif; Kozan, Hatice; Eroglu, Serpil; Pirat, Bahar; Aydinalp, Alp; Sezgin, Atilla; Muderrisoglu, Haldun

2017-02-01

Residual pulmonary hypertension challenges the right ventricular function and worsens the prognosis in heart transplant recipients. The complex geometry of the right ventricle complicates estimation of its function with conventional transthoracic echocardiography. We evaluated right ventricular function in heart transplant recipients with the use of 3-dimensional echocardiography in relation to systolic pulmonary artery pressure. We performed 32 studies in 26 heart transplant patients, with 6 patients having 2 studies at different time points with different pressures and thus included. Right atrial volume, tricuspid annular plane systolic excursion, peak systolic annular velocity, fractional area change, and 2-dimensional speckle tracking longitudinal strain were obtained by 2-dimensional and tissue Doppler imaging. Three-dimensional right ventricular volumes, ejection fraction, and 3-dimensional right ventricular strain were obtained from the 3-dimensional data set by echocardiographers. Systolic pulmonary artery pressure was obtained during right heart catheterization. Overall mean systolic pulmonary artery pressure was 26 ± 7 mm Hg (range, 14-44 mmHg). Three-dimensional end-diastolic (r = 0.75; P < .001) and end-systolic volumes (r = 0.55; P = .001)correlated well with systolic pulmonary artery pressure. Right ventricular ejection fraction and right atrium volume also significantly correlated with systolic pulmonary artery pressure (r = 0.49 and P = .01 for both). However, right ventricular 2- and 3-dimensional strain, tricuspid annular plane systolic excursion, and tricuspid annular velocity did not. The effects of pulmonary hemodynamic burden on right ventricular function are better estimated by a 3-dimensional volume evaluation than with 3-dimensional longitudinal strain and other 2-dimensional and tissue Doppler measurements. These results suggest that the peculiar anatomy of the right ventricle necessitates 3-dimensional volume quantification in heart transplant recipients in relation to residual pulmonary hypertension.

Dynamical relations for left ventricular ejection - Flow rate, momentum, force and impulse

NASA Technical Reports Server (NTRS)

Back, L. H.; Selzer, R. H.; Gordon, D. G.; Ledbetter, D. C.; Crawford, D. W.

1984-01-01

An investigation was carried out to quantitatively evaluate left ventricular volume flow rate, momentum, force and impulse derived from application of conservation principles for mass and momentum of blood within the ventricle during the ejection phase. An automated digital image processing system was developed and applied to left ventricular angiograms which are computer processed and analyzed frame by frame to determine the dynamical relations by numerical methods. The initial experience with force and impulse has indicated that neither quantity seemed to be a sensitive indicator of coronary artery disease as evaluated by qualitative angiography for the particular patient group studied. Utilization of the dynamical relations in evaluating human left ventricular performance requires improved means of measurement and interpretation of clinical studies.

Use of a Doppler pulmonary artery catheter for continuous measurement of right ventricular pump function and contractility during single lung transplantation.

PubMed

Heerdt, P M; Pond, C G; Kussman, M K; Triantafillou, A N

1993-01-01

Despite numerous technologic advances in intraoperative monitoring, the only methods routinely available for assessment of right ventricular function in lung transplant recipients are continuous measurement of right heart pressures and intermittent thermodilution determination of cardiac output and ejection fraction. Additional data may now be obtained with transesophageal echocardiography, although this technology is expensive and not widely available and requires diverting attention from a potentially unstable patient for data acquisition and analysis. Recently, a Doppler pulmonary artery catheter was introduced that measures beat-to-beat pulmonary artery blood flow-velocity, cross sectional area, and volume flow. Because of data indicating that acceleration of blood in the pulmonary artery (measured as the first derivative of either the velocity or flow waveform) is a sensitive indicator of right ventricular contractility, we have used waveforms obtained with the catheter for assessment of right ventricular pump function (stroke volume and peak pulmonary artery flow rate) and contractility in heart surgery patients. We report here our experience with this method in two patients undergoing left single lung transplantation.

Left ventricular function assessment using a fast 3D gradient echo pulse sequence: comparison to standard multi-breath hold 2D steady state free precession imaging and accounting for papillary muscles and trabeculations.

PubMed

Sievers, Burkhard; Schrader, Sebastian; Rehwald, Wolfgang; Hunold, Peter; Barkhausen, Joerg; Erbel, Raimund

2011-06-01

Papillary muscles and trabeculae for ventricular function analysis are known to significantly contribute to accurate volume and mass measurements. Fast imaging techniques such as three-dimensional steady-state free precession (3D SSFP) are increasingly being used to speed up imaging time, but sacrifice spatial resolution. It is unknown whether 3D SSFP, despite its reduced spatial resolution, allows for exact delineation of papillary muscles and trabeculations. We therefore compared 3D SSFP ventricular function measurements to those measured from standard multi-breath hold two-dimensional steady-state free precession cine images (standard 2D SSFP). 14 healthy subjects and 14 patients with impaired left ventricularfunction underwent 1.5 Tesla cine imaging. A stack of short axis images covering the left ventricle was acquired with 2D SSFP and 3D SSFP. Left ventricular volumes, ejection fraction, and mass were determined. Analysis was performed by substracting papillary muscles and trabeculae from left ventricular volumes. In addition, reproducibility was assessed. EDV, ESV, EF, and mass were not significantly different between 2D SSFP and 3D SSFP (mean difference healthy subjects: -0.06 +/- 3.2 ml, 0.54 +/- 2.2 ml, -0.45 +/- 1.8%, and 1.13 +/- 0.8 g, respectively; patients: 1.36 +/- 2.8 ml, -0.15 3.5 ml, 0.86 +/- 2.5%, and 0.91 +/- 0.9 g, respectively; P > or = 0.095). Intra- and interobserver variability was not different for 2D SSFP (P > or = 0.64 and P > or = 0.397) and 3D SSFP (P > or = 0.53 and P > or = 0.47). Differences in volumes, EF, and mass measurements between 3D SSFP and standard 2D SSFP are very small, and not statistically significant. 3D SSFP may be used for accurate ventricular function assessment when papillary muscles and trabeculations are to be taken into account.

Clinical review: Positive end-expiratory pressure and cardiac output

PubMed Central

Luecke, Thomas; Pelosi, Paolo

2005-01-01

In patients with acute lung injury, high levels of positive end-expiratory pressure (PEEP) may be necessary to maintain or restore oxygenation, despite the fact that 'aggressive' mechanical ventilation can markedly affect cardiac function in a complex and often unpredictable fashion. As heart rate usually does not change with PEEP, the entire fall in cardiac output is a consequence of a reduction in left ventricular stroke volume (SV). PEEP-induced changes in cardiac output are analyzed, therefore, in terms of changes in SV and its determinants (preload, afterload, contractility and ventricular compliance). Mechanical ventilation with PEEP, like any other active or passive ventilatory maneuver, primarily affects cardiac function by changing lung volume and intrathoracic pressure. In order to describe the direct cardiocirculatory consequences of respiratory failure necessitating mechanical ventilation and PEEP, this review will focus on the effects of changes in lung volume, factors controlling venous return, the diastolic interactions between the ventricles and the effects of intrathoracic pressure on cardiac function, specifically left ventricular function. Finally, the hemodynamic consequences of PEEP in patients with heart failure, chronic obstructive pulmonary disease and acute respiratory distress syndrome are discussed. PMID:16356246

Electrophysiological determinants of hypokalaemia-induced arrhythmogenicity in the guinea-pig heart.

PubMed

Osadchii, O E; Olesen, S P

2009-12-01

Hypokalaemia is an independent risk factor contributing to arrhythmic death in cardiac patients. In the present study, we explored the mechanisms of hypokalaemia-induced tachyarrhythmias by measuring ventricular refractoriness, spatial repolarization gradients, and ventricular conduction time in isolated, perfused guinea-pig heart preparations. Epicardial and endocardial monophasic action potentials from distinct left ventricular (LV) and right ventricular (RV) recording sites were monitored simultaneously with volume-conducted electrocardiogram (ECG) during steady-state pacing and following a premature extrastimulus application at progressively reducing coupling stimulation intervals in normokalaemic and hypokalaemic conditions. Hypokalaemic perfusion (2.5 mm K(+) for 30 min) markedly increased the inducibility of tachyarrhythmias by programmed ventricular stimulation and rapid pacing, prolonged ventricular repolarization and shortened LV epicardial and endocardial effective refractory periods, thereby increasing the critical interval for LV re-excitation. Hypokalaemia increased the RV-to-LV transepicardial repolarization gradients but had no effect on transmural dispersion of APD(90) and refractoriness across the LV wall. As determined by local activation time recordings, the LV-to-RV transepicardial conduction and the LV transmural (epicardial-to-endocardial) conduction were slowed in hypokalaemic heart preparations. This change was attributed to depressed diastolic excitability as evidenced by increased ventricular pacing thresholds. These findings suggest that hypokalaemia-induced arrhythmogenicity is attributed to shortened LV refractoriness, increased critical intervals for LV re-excitation, amplified RV-to-LV transepicardial repolarization gradients and slowed ventricular conduction in the guinea-pig heart.

Left ventricular function before and after kidney transplantation.

PubMed

Omran, Mohammad T; Khakpour, Somayeh; Oliaie, Farshid

2009-06-01

To evaluate left ventricular function by echocardiography before and after kidney transplantation (KT). This analytical study included 50 patients that had successful KT in Shahid Beheshti Hospital, Babol, Iran from October 2005 to December 2007. The echocardiography study was performed by one cardiologist before and at least 3 months after KT. Data were analyzed by SPSS, and a p<0.05 was considered statistically significant. The mean age of patients was 33.94 +/- 11.66 years, 66% were male and 56% less than 45 years old. The ejection fraction and stroke volume after KT increased, however, the left ventricular end diastolic volume, left ventricular end systolic volume, left ventricular end systolic dimension, and left ventricular end diastolic diameter decreased. In patients with end stage renal disease, successful kidney transplantation could improve the function of the left ventricle.

Characterization of fluid physics effects on cardiovascular response to microgravity (G-572)

NASA Technical Reports Server (NTRS)

Pantalos, George M.; Sharp, M. Keith; Woodruff, Stewart J.; Lorange, Richard D.; Bennett, Thomas E.; Sojka, Jan J.; Lemon, Mark W.

1993-01-01

The recognition and understanding of cardiovascular adaptation to spaceflight has experienced substantial advancement in the last several years. In-flight echocardiographic measurements of astronaut cardiac function on the Space Shuttle have documented a 15 percent reduction in both left ventricular volume index and stroke volume with a compensatory increase in heart rate to maintain cardiac output. To date, the reduced cardiac size and stroke volume have been presumed to be the consequence of the reduction in circulating fluid volume following diuresis and other physiological processes to reduce blood volume within a few days after orbital insertion. However, no specific mechanism for the reduced stroke volume has been elucidated. The following investigation proposes the use of a hydraulic model of the cardiovascular system to examine the possibility that the observed reduction in stroke volume may, in part, be related to fluid physics effects on heart function. The automated model is being prepared to fly as a GAS payload. The experimental apparatus consists of a pneumatically actuated, elliptical artificial ventricle connected to a closed-loop, hydraulic circuit with compliance and resistance elements to create physiologic pressure and flow conditions. The ventricle is instrumented with high-fidelity, acceleration-insensitive, catheter-tip pressure transducers (Millar Instruments) in the apex and base to determine the instantaneous ventricular pressures and (delta)P(sub LV) across the left ventricle (LVP(sub apex)-LVP(sub base). The ventricle is also instrumented with a flow probe and pressure transducers immediately upstream of the inflow valve and downstream of the outflow valve. The experiment will be microprocessor controlled with analog signals stored on the FM data tape recorder. By varying the circulating fluid volume, ventricular function can be determined for varying preload pressures with fixed afterload pressure. Pilot experiments on board the NASA KC-135 aircraft have demonstrated proof-of-concept and provided early support for the proposed hypothesis. A review of the pilot experiments and developmental progress on the GAS version of this experiment will be presented.

Impact of Major Pulmonary Resections on Right Ventricular Function: Early Postoperative Changes.

PubMed

Elrakhawy, Hany M; Alassal, Mohamed A; Shaalan, Ayman M; Awad, Ahmed A; Sayed, Sameh; Saffan, Mohammad M

2018-01-15

Right ventricular (RV) dysfunction after pulmonary resection in the early postoperative period is documented by reduced RV ejection fraction and increased RV end-diastolic volume index. Supraventricular arrhythmia, particularly atrial fibrillation, is common after pulmonary resection. RV assessment can be done by non-invasive methods and/or invasive approaches such as right cardiac catheterization. Incorporation of a rapid response thermistor to pulmonary artery catheter permits continuous measurements of cardiac output, right ventricular ejection fraction, and right ventricular end-diastolic volume. It can also be used for right atrial and right ventricular pacing, and for measuring right-sided pressures, including pulmonary capillary wedge pressure. This study included 178 patients who underwent major pulmonary resections, 36 who underwent pneumonectomy assigned as group (I) and 142 who underwent lobectomy assigned as group (II). The study was conducted at the cardiothoracic surgery department of Benha University hospital in Egypt; patients enrolled were operated on from February 2012 to February 2016. A rapid response thermistor pulmonary artery catheter was inserted via the right internal jugular vein. Preoperatively the following was recorded: central venous pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac output, right ventricular ejection fraction and volumes. The same parameters were collected in fixed time intervals after 3 hours, 6 hours, 12 hours, 24 hours, and 48 hours postoperatively. For group (I): There were no statistically significant changes between the preoperative and postoperative records in the central venous pressure and mean arterial pressure; there were no statistically significant changes in the preoperative and 12, 24, and 48 hour postoperative records for cardiac index; 3 and 6 hours postoperative showed significant changes. There were statistically significant changes between the preoperative and postoperative records for heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction and right ventricular end diastolic volume index, in all postoperative records. For group (II): There were no statistically significant changes between the preoperative and all postoperative records for the central venous pressure, mean arterial pressure and cardiac index. There were statistically significant changes between the preoperative and postoperative records for heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction and right ventricular end diastolic volume index in all postoperative records. There were statistically significant changes between the two groups in all postoperative records for heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction and right ventricular end diastolic volume index. There is right ventricular dysfunction early after major pulmonary resection caused by increased right ventricular afterload. This dysfunction is more present in pneumonectomy than in lobectomy. Heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction, and right ventricular end diastolic volume index are significantly affected by pulmonary resection.

Right ventricular involvement in cardiac sarcoidosis demonstrated with cardiac magnetic resonance

PubMed Central

van Geuns, Robert‐Jan; Ainslie, Gillian; Ector, Joris; Heidbuchel, Hein; Crijns, Harry J.G.M.

2017-01-01

Abstract Aims Cardiac involvement in sarcoidosis is reported in up to 30% of patients. Left ventricular involvement demonstrated by contrast‐enhanced cardiac magnetic resonance has been well validated. We sought to determine the prevalence and distribution of right ventricular late gadolinium enhancement in patients diagnosed with pulmonary sarcoidosis. Methods and results We prospectively evaluated 87 patients diagnosed with pulmonary sarcoidosis with contrast‐enhanced cardiac magnetic resonance for right ventricular involvement. Pulmonary artery pressures were non‐invasively evaluated with Doppler echocardiography. Patient characteristics were compared between the groups with and without right ventricular involvement, and right ventricular enhancement was correlated with pulmonary hypertension, ventricular mass, volume, and systolic function. Left ventricular late gadolinium enhancement was demonstrated in 30 patients (34%). Fourteen patients (16%) had right ventricular late gadolinium enhancement, with sole right ventricular enhancement in only two patients. The pattern of right ventricular enhancement consisted of right ventricular outflow tract enhancement in 1 patient, free wall enhancement in 8 patients, ventricular insertion point enhancement in 10 patients, and enhancement of the right side of the interventricular septum in 11 patients. Pulmonary arterial hypertension correlated with the presence of right ventricular enhancement (P < 0.001). Right ventricular enhancement correlated with systolic ventricular dysfunction (P < 0.001), hypertrophy (P = 0.001), and dilation (P < 0.001). Conclusions Right ventricular enhancement was present in 16% of patients diagnosed with pulmonary sarcoidosis and in 48% of patients with left ventricular enhancement. The presence of right ventricular enhancement correlated with pulmonary arterial hypertension, right ventricular systolic dysfunction, hypertrophy, and dilation. PMID:29154434

Embryonic cardiac morphometry in Carnegie stages 15-23, from the Complutense University of Madrid Institute of Embryology Human Embryo Collection.

PubMed

Arráez-Aybar, L A; Turrero-Nogués, A; Marantos-Gamarra, D G

2008-01-01

We performed a morphometric study of cardiac development on human embryos to complement the scarce data on human embryonic cardiac morphometry and to attempt to establish, from these, algorithms describing cardiac growth during the second month of gestation. Thirty human embryos from Carnegie stages 15-23 were included in the study. Shrinkage and compression effects from fixation and inclusion in paraffin were considered in our calculations. Growth of the cardiac (whole heart) volume and volume of ventricular myocardium through the Carnegie stages were analysed by ANOVA. Linear correlation was used to describe the relationship between the ventricular myocardium and cardiac volumes. Comparisons of models were carried out through the R2 statistic. The relationship volume of ventricular myocardium versus cardiac volume is expressed by the equation: cardiac volume = 0.6266 + 2.4778 volume of ventricular myocardium. The relationship cardiac volume versus crown-rump length is expressed by the equation: cardiac volume = 1.3 e(0.126 CR length), where e is the base of natural logarithms. At a clinical level, these results can contribute towards the establishment of a normogram for cardiac development, useful for the design of strategies for early diagnosis of congenital heart disease. They can also help in the study of embryogenesis, for example in the discussion of ventricular trabeculation. Copyright 2007 S. Karger AG, Basel.

The Cardiovascular Effects of Obesity on Ventricular Function and Mass in Patients after Tetralogy of Fallot Repair.

PubMed

Fogel, Mark A; Pawlowski, Thomas; Keller, Marc S; Cohen, Meryl S; Goldmuntz, Elizabeth; Diaz, Laura; Li, Christine; Whitehead, Kevin K; Harris, Matthew A

2015-08-01

To determine the cardiovascular effects of obesity on patients with tetralogy of Fallot (TOF) repair. Ventricular performance measures were compared between obese (body mass index [BMI] ≥95%), overweight (85% ≤BMI <95%), and normal weight subjects (BMI <85%) in a retrospective review of patients with TOF who underwent cardiac magnetic resonance from 2005-2010. Significance was P < .05. Of 260 consecutive patients with TOF, 32 were obese (12.3%), 48 were overweight (18.5%), and 180 were normal weight (69.2%). Biventricular mass was increased in obese compared with normal weight patients with right ventricular mass more affected than left ventricular mass. Obese patients demonstrated decreased biventricular end-diastolic volume (EDV) and stroke volume (SV) when indexed to body surface area (BSA) with an increased heart rate when compared with normal weight patients; cardiac index, ejection fraction, and pulmonary regurgitation fraction were similar. When indexed to ideal BSA, biventricular EDV and SV were similar. EDV and SV for overweight patients were nearly identical to normal weight patients with ventricular mass in between the other 2 groups. Approximately 12% of patients after TOF repair referred for cardiac magnetic resonance in a tertiary referral center are obese with increased biventricular mass. Obese patients and normal weight patients have similar cardiac indices, however, when indexed to actual BSA, obese patients demonstrate decreased EDV and SV with increased heart rate and similar cardiac indices. When indexed to ideal BSA, no differences in biventricular volumes were noted. Copyright © 2015. Published by Elsevier Inc.

WEB downloadable software for training in cardiovascular hemodynamics in the (3-D) stress echo lab

PubMed Central

2010-01-01

When a physiological (exercise) stress echo is scheduled, interest focuses on wall motion segmental contraction abnormalities to diagnose ischemic response to stress, and on left ventricular ejection fraction to assess contractile reserve. Echocardiographic evaluation of volumes (plus standard assessment of heart rate and blood pressure) is ideally suited for the quantitative and accurate calculation of a set of parameters allowing a complete characterization of cardiovascular hemodynamics (including cardiac output and systemic vascular resistance), left ventricular elastance (mirroring left ventricular contractility, theoretically independent of preload and afterload changes heavily affecting the ejection fraction), arterial elastance, ventricular arterial coupling (a central determinant of net cardiovascular performance in normal and pathological conditions), and diastolic function (through the diastolic mean filling rate). All these parameters were previously inaccessible, inaccurate or labor-intensive and now become, at least in principle, available in the stress echocardiography laboratory since all of them need an accurate estimation of left ventricular volumes and stroke volume, easily derived from 3 D echo. Aims of this paper are: 1) to propose a simple method to assess a set of parameters allowing a complete characterization of cardiovascular hemodynamics in the stress echo lab, from basic measurements to calculations 2) to propose a simple, web-based software program, to learn and training calculations as a phantom of the everyday activity in the busy stress echo lab 3) to show examples of software testing in a way that proves its value. The informatics infrastructure is available on the web, linking to http://cctrainer.ifc.cnr.it PMID:21073738

Knowledge-based reconstruction for measurement of right ventricular volumes on cardiovascular magnetic resonance images in a mixed population.

PubMed

Pieterman, Elise D; Budde, Ricardo P J; Robbers-Visser, Daniëlle; van Domburg, Ron T; Helbing, Willem A

2017-09-01

Follow-up of right ventricular performance is important for patients with congenital heart disease. Cardiac magnetic resonance imaging is optimal for this purpose. However, observer-dependency of manual analysis of right ventricular volumes limit its use. Knowledge-based reconstruction is a new semiautomatic analysis tool that uses a database including knowledge of right ventricular shape in various congenital heart diseases. We evaluated whether knowledge-based reconstruction is a good alternative for conventional analysis. To assess the inter- and intra-observer variability and agreement of knowledge-based versus conventional analysis of magnetic resonance right ventricular volumes, analysis was done by two observers in a mixed group of 22 patients with congenital heart disease affecting right ventricular loading conditions (dextro-transposition of the great arteries and right ventricle to pulmonary artery conduit) and a group of 17 healthy children. We used Bland-Altman analysis and coefficient of variation. Comparison between the conventional method and the knowledge-based method showed a systematically higher volume for the latter group. We found an overestimation for end-diastolic volume (bias -40 ± 24 mL, r = .956), end-systolic volume (bias -34 ± 24 mL, r = .943), stroke volume (bias -6 ± 17 mL, r = .735) and an underestimation of ejection fraction (bias 7 ± 7%, r = .671) by knowledge-based reconstruction. The intra-observer variability of knowledge-based reconstruction varied with a coefficient of variation of 9% for end-diastolic volume and 22% for stroke volume. The same trend was noted for inter-observer variability. A systematic difference (overestimation) was noted for right ventricular size as assessed with knowledge-based reconstruction compared with conventional methods for analysis. Observer variability for the new method was comparable to what has been reported for the right ventricle in children and congenital heart disease with conventional analysis. © 2017 Wiley Periodicals, Inc.

Quantitative Computed Tomography Ventriculography for Assessment and Monitoring of Hydrocephalus: A Pilot Study and Description of Method in Subarachnoid Hemorrhage.

PubMed

Multani, Jasjit Singh; Oermann, Eric Karl; Titano, Joseph; Mascitelli, Justin; Nicol, Kelly; Feng, Rui; Skovrlj, Branko; Pain, Margaret; Mocco, J D; Bederson, Joshua B; Costa, Anthony; Shrivastava, Raj

2017-08-01

There is no facile quantitative method for monitoring hydrocephalus (HCP). We propose quantitative computed tomography (CT) ventriculography (qCTV) as a novel computer vision tool for empirically assessing HCP in patients with subarachnoid hemorrhage (SAH). Twenty patients with SAH who were evaluated for ventriculoperitoneal shunt (VPS) placement were selected for inclusion. Ten patients with normal head computed tomography (CTH) findings were analyzed as negative controls. CTH scans were segmented both manually and automatically (by qCTV) to generate measures of ventricular volume. The median manually calculated ventricular volume was 36.1 cm 3 (interquartile range [IQR], 30-115 cm 3 ), which was similar to the median qCTV measured volume of 37.5 cm 3 (IQR, 32-118 cm 3 ) (P = 0.796). Patients undergoing VPS placement demonstrated an increase in median ventricular volume on qCTV from 21 cm 3 to 40 cm 3 on day T-2 and to 51 cm 3 by day 0, a change of 144%. This is in contrast to patients who did not require shunting, in whom median ventricular volume decreased from 16 cm 3 to 14 cm 3 on day T-2 and to 13 cm 3 by day 0, with an average overall volume decrease 19% (P = 0.001). The average change in ventricular volume predicted which patients would require VPS placement, successfully identifying 7 of 10 patients (P = 0.004). Using an optimized cutoff of a change in ventricular volume of 2.5 cm 3 identified all patients who went on to require VPS placement (10 of 10; P = 0.011). qCTV is a reliable means of quantifying ventricular volume and hydrocephalus. This technique offers a new tool for monitoring neurosurgical patients for hydrocephalus, and may be beneficial for use in future research studies, as well as in the routine care of patients with hydrocephalus. Copyright © 2017 Elsevier Inc. All rights reserved.

Masked hypertension and cardiac remodeling in middle-aged endurance athletes.

PubMed

Trachsel, Lukas D; Carlen, Frederik; Brugger, Nicolas; Seiler, Christian; Wilhelm, Matthias

2015-06-01

Extensive endurance training and arterial hypertension are established risk factors for atrial fibrillation. We aimed to assess the proportion of masked hypertension in endurance athletes and the impact on cardiac remodeling, mechanics, and supraventricular tachycardias (SVT). Male participants of a 10-mile race were recruited and included if office blood pressure was normal (<140/90 mmHg). Athletes were stratified into a masked hypertension and normotension group by ambulatory blood pressure. Primary endpoint was diastolic function, expressed as peak early diastolic mitral annulus velocity (E'). Left ventricular global strain, left ventricular mass/volume ratio, left atrial volume index, signal-averaged P-wave duration (SAPWD), and SVT during 24-h Holter monitoring were recorded. From 108 runners recruited, 87 were included in the final analysis. Thirty-three (38%) had masked hypertension. The mean age was 42 ± 8 years. Groups did not differ with respect to age, body composition, cumulative training hours, and 10-mile race time. Athletes with masked hypertension had a lower E' and a higher left ventricular mass/volume ratio. Left ventricular global strain, left atrial volume index, SAPWD, and SVT showed no significant differences between the groups. In multiple linear regression analysis, masked hypertension was independently associated with E' (beta = -0.270, P = 0.004) and left ventricular mass/volume ratio (beta = 0.206, P = 0.049). Cumulative training hours was the only independent predictor for left atrial volume index (beta = 0.474, P < 0.001) and SAPWD (beta = 0.481, P < 0.001). In our study, a relevant proportion of middle-aged athletes had masked hypertension, associated with a lower diastolic function and a higher left ventricular mass/volume ratio, but unrelated to left ventricular systolic function, atrial remodeling, or SVT.

Brain morphology in older African Americans, Caribbean Hispanics, and whites from northern Manhattan.

PubMed

Brickman, Adam M; Schupf, Nicole; Manly, Jennifer J; Luchsinger, José A; Andrews, Howard; Tang, Ming X; Reitz, Christiane; Small, Scott A; Mayeux, Richard; DeCarli, Charles; Brown, Truman R

2008-08-01

Aging is accompanied by a decrease in brain volume and by an increase in cerebrovascular disease. To examine the effects of age, sex, race/ethnicity, and vascular disease history on measures of brain morphology, including relative brain volume, ventricular volume, hippocampus and entorhinal cortex volumes, and white matter hyperintensity (WMH) burden, in a large community-based cohort of racially/ethnically diverse older adults without dementia. The associations of age, sex, race/ethnicity, and self-reported vascular disease history with brain morphology were examined in a cross-sectional study using multiple linear regression analyses. Sex x race/ethnicity interactions were also considered. The Washington Heights-Inwood Columbia Aging Project, a community-based epidemiological study of older adults from 3 racial/ethnic groups (white, Hispanic, and African American) from northern Manhattan. Beginning in 2003, high-resolution quantitative magnetic resonance (MR) images were acquired in 769 participants without dementia. Relative brain volume (total brain volume/intracranial volume), ventricular volume, and hippocampus and entorhinal cortex volumes were derived manually on high-resolution MR images. White matter hyperintensities were quantified semiautomatically on fluid-attenuated inversion recovery-T2-weighted MR images. Older age was associated with decreased relative brain volume and with increased ventricular and WMH volumes. Hispanic and African American participants had larger relative brain volumes and more severe WMH burden than white participants, but the associations of these variables with age were similar across racial/ethnic groups. Compared with men, women had larger relative brain volumes. Vascular disease was associated with smaller relative brain volume and with higher WMH burden, particularly among African Americans. Older age and vascular disease, particularly among African Americans, are associated with increased brain atrophy and WMH burden. African American and Hispanic subjects have larger relative brain volumes and more WMH than white subjects. Racial/ethnic group differences in WMH severity seem to be partially attributable to differences in vascular disease. Future work will focus on the determinants and cognitive correlates of these differences.

Plasma bilirubin values on admission and ventricular remodeling after a first anterior ST-segment elevation acute myocardial infarction.

PubMed

Miranda, Berta; Barrabés, José A; Figueras, Jaume; Pineda, Victor; Rodríguez-Palomares, José; Lidón, Rosa-Maria; Sambola, Antonia; Bañeras, Jordi; Otaegui, Imanol; García-Dorado, David

2016-01-01

Bilirubin may elicit cardiovascular protection and heme oxygenase-1 overexpression attenuated post-infarction ventricular remodeling in experimental animals, but the association between bilirubin levels and post-infarction remodeling is unknown. In 145 patients with a first anterior ST-segment elevation acute myocardial infarction (STEMI), we assessed whether plasma bilirubin on admission predicted adverse remodeling (left ventricular end-diastolic volume [LVEDV] increase ≥20% between discharge and 6 months, estimated by magnetic resonance imaging). Patients' baseline characteristics and management were comparable among bilirubin tertiles. LVEDV increased at 6 months (P < 0.001) with respect to the initial exam, but the magnitude of this increase was similar across increasing bilirubin tertiles (10.8 [30.2], 10.1 [22.9], and 12.7 [24.3]%, P = 0.500). Median (25-75 percentile) bilirubin values in patients with and without adverse remodeling were 0.75 (0.60-0.93) and 0.73 (0.60-0.92) mg/dL (P = 0.693). Absence of final TIMI flow grade 3 (odds ratio 3.92, 95% CI 1.12-13.66) and a history of hypertension (2.04, 0.93-4.50), but not admission bilirubin, were independently associated with adverse remodeling. Bilirubin also did not predict the increase in ejection fraction at 6 months. Admission bilirubin values are not related to LVEDV or ejection fraction progression after a first anterior STEMI and do not predict adverse ventricular remodeling. Key messages Bilirubin levels are inversely related to cardiovascular disease, and overexpression of heme oxygenase-1 (the enzyme that determines bilirubin production) has prevented post-infarction ventricular remodeling in experimental animals, but the association between bilirubin levels and the progression of ventricular volumes and function in patients with acute myocardial infarction remained unexplored. In this cohort of patients with a first acute anterior ST-segment elevation myocardial infarction receiving contemporary management, bilirubin levels on admission were not predictive of the changes in left ventricular volumes or ejection fraction at 6 months measured by serial cardiac magnetic resonance imaging. The data are contrary to a significant protective effect of bilirubin against post-infarction ventricular remodeling.

Propionyl-L-carnitine limits chronic ventricular dilation after myocardial infarction in rats.

PubMed

Micheletti, R; Di Paola, E D; Schiavone, A; English, E; Benatti, P; Capasso, J M; Anversa, P; Bianchi, G

1993-04-01

To determine whether propionyl-L-carnitine (PLC) administration ameliorates ventricular remodeling after myocardial infarction, we performed coronary occlusion in rats and examined the long-term effects of the drug 19-24 wk after surgery. In view of the well-established role of angiotensin-converting enzyme (ACE) inhibitors in the reduction of ventricular dilation after infarction, the therapeutic impact of oral PLC (60 mg/kg) was compared with that of enalapril (1 mg/kg). Infarct size measured planimetrically was found to be comparable in untreated, PLC-treated, and enalapril-treated rats, averaging 40-46% of the left ventricular free wall. Heart weight was increased 14, 16, and 11% with no treatment, with PLC, and with enalapril, respectively. The relationship between left ventricular filling pressure and chamber volume demonstrated that PLC and enalapril significantly prevented the expansion in cavitary size after infarction. These protective influences were observed throughout the range of filling pressures measured, from 0 to 30 mmHg. At a uniform reference point of filling pressure of 4 mmHg, untreated infarcted hearts showed an expansion in ventricular volume of 2.17-fold (P < 0.0001). Corresponding increases in this parameter after PLC and enalapril were 36 and 43%, respectively, both not statistically significant. Moreover, PLC was capable of reducing the alterations in myocardial compliance associated with myocardial infarction. In conclusion, PLC reduces the magnitude of decompensated eccentric hypertrophy produced by myocardial infarction in a manner similar to that found with ACE inhibition.

Mitral annulus size links ventricular dilatation to functional mitral regurgitation.

PubMed

Popović, Zoran B; Martin, Maureen; Fukamachi, Kiyotaka; Inoue, Masahiro; Kwan, Jun; Doi, Kazuyoshi; Qin, Jian Xin; Shiota, Takahiro; Garcia, Mario J; McCarthy, Patrick M; Thomas, James D

2005-09-01

We compared the impact of annulus size and valve deformation (tethering) on mitral regurgitation in the animal dilated cardiomyopathy model, and assessed if acute left ventricular volume changes affect mitral annulus dimensions. We performed 3-dimensional echocardiography in 30 open-chest dogs with pacing-induced cardiomyopathy. Mitral annulus area was calculated from its two orthogonal diameters, whereas valve tethering was quantified by valve tenting area measurement. Mitral valve regurgitant volume showed the highest correlation with annulus area (r = 0.64, P < .001), left atrial volume (r = 0.40, P < .01), and left ventricular end-diastolic volume (r = 0.37, P < .01). Regurgitant volume showed poorer correlation with valve tethering in both septolateral and intercommissural planes (r = 0.35 and r = 0.31, P < .05 for both). Annulus dimensions correlated with acute changes of left ventricular end-diastolic volume (r = 0.68, P = .002). Mitral annulus dilation is the strongest predictor of functional mitral regurgitation in this animal dilated cardiomyopathy model.

Right Heart Vortex Entrainment Volume and Right Ventricular Diastolic Dysfunction

NASA Astrophysics Data System (ADS)

Browning, James; Hertzberg, Jean; Fenster, Brett; Schroeder, Joyce

2014-11-01

Recent advances in cardiac magnetic resonance imaging (CMR) have allowed for the 3-dimensional characterization of blood flow in the right ventricle (RV) and right atrium (RA). In this study, we investigate and quantify differences in the characteristics of coherent rotating flow structures (vortices) in the RA and RV between subjects with right ventricular diastolic dysfunction (RVDD) and normal controls. Fifteen RVDD subjects and 10 age-matched controls underwent same day 3D time resolved CMR and echocardiography. Echocardiography was used to determine RVDD stage as well as pulmonary artery systolic pressure (PASP). CMR data was used for RA and RV vortex quantification and visualization during early and late ventricular diastole. RA and RV vortex entrainment volume is quantified and visualized using the Lambda-2 criterion, and the results are compared between healthy subjects and those with RVDD. The resulting trends are discussed and hypotheses are presented regarding differences in vortex characteristics between healthy and RVDD subjects cohorts.

A Pilot Study of Quantitative MRI Measurements of Ventricular Volume and Cortical Atrophy for the Differential Diagnosis of Normal Pressure Hydrocephalus

PubMed Central

Moore, Dana W.; Kovanlikaya, Ilhami; Heier, Linda A.; Raj, Ashish; Huang, Chaorui; Chu, King-Wai; Relkin, Norman R.

2012-01-01

Current radiologic diagnosis of normal pressure hydrocephalus (NPH) requires a subjective judgment of whether lateral ventricular enlargement is disproportionate to cerebral atrophy based on visual inspection of brain images. We investigated whether quantitative measurements of lateral ventricular volume and total cortical thickness (a correlate of cerebral atrophy) could be used to more objectively distinguish NPH from normal controls (NC), Alzheimer's (AD), and Parkinson's disease (PD). Volumetric MRIs were obtained prospectively from patients with NPH (n = 5), PD (n = 5), and NC (5). Additional NC (n = 5) and AD patients (n = 10) from the ADNI cohort were examined. Although mean ventricular volume was significantly greater in the NPH group than all others, the range of values overlapped those of the AD group. Individuals with NPH could be better distinguished when ventricular volume and total cortical thickness were considered in combination. This pilot study suggests that volumetric MRI measurements hold promise for improving NPH differential diagnosis. PMID:21860791

Right ventricular involvement in cardiac sarcoidosis demonstrated with cardiac magnetic resonance.

PubMed

Smedema, Jan-Peter; van Geuns, Robert-Jan; Ainslie, Gillian; Ector, Joris; Heidbuchel, Hein; Crijns, Harry J G M

2017-11-01

Cardiac involvement in sarcoidosis is reported in up to 30% of patients. Left ventricular involvement demonstrated by contrast-enhanced cardiac magnetic resonance has been well validated. We sought to determine the prevalence and distribution of right ventricular late gadolinium enhancement in patients diagnosed with pulmonary sarcoidosis. We prospectively evaluated 87 patients diagnosed with pulmonary sarcoidosis with contrast-enhanced cardiac magnetic resonance for right ventricular involvement. Pulmonary artery pressures were non-invasively evaluated with Doppler echocardiography. Patient characteristics were compared between the groups with and without right ventricular involvement, and right ventricular enhancement was correlated with pulmonary hypertension, ventricular mass, volume, and systolic function. Left ventricular late gadolinium enhancement was demonstrated in 30 patients (34%). Fourteen patients (16%) had right ventricular late gadolinium enhancement, with sole right ventricular enhancement in only two patients. The pattern of right ventricular enhancement consisted of right ventricular outflow tract enhancement in 1 patient, free wall enhancement in 8 patients, ventricular insertion point enhancement in 10 patients, and enhancement of the right side of the interventricular septum in 11 patients. Pulmonary arterial hypertension correlated with the presence of right ventricular enhancement (P < 0.001). Right ventricular enhancement correlated with systolic ventricular dysfunction (P < 0.001), hypertrophy (P = 0.001), and dilation (P < 0.001). Right ventricular enhancement was present in 16% of patients diagnosed with pulmonary sarcoidosis and in 48% of patients with left ventricular enhancement. The presence of right ventricular enhancement correlated with pulmonary arterial hypertension, right ventricular systolic dysfunction, hypertrophy, and dilation. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

Importance of the mitral apparatus for left ventricular function: an experimental approach.

PubMed

Gams, E; Hagl, S; Schad, H; Heimisch, W; Mendler, N; Sebening, F

1992-01-01

In an experimental study of 31 anesthetized dogs the importance of the mitral apparatus for the left ventricular function was investigated. During extracorporeal circulation bileaflet mitral valve prostheses were implanted preserving the mitral subvalvular apparatus. Flexible wires were slung around the chordae tendineae and exteriorized through the left ventricular wall to cut the chordae by electrocautery from the outside when the heart was beating again. External and internal left ventricular dimensions were measured by sonomicrometry, left ventricular stroke volume by electromagnetic flowmeters around the ascending aorta, left ventricular end-diastolic volume by dye dilution technique, and left ventricular pressure by catheter tip manometers. Different preload levels were achieved by volume loading with blood transfusion before and after cutting the chordae tendineae. When the chordae had been divided peak systolic left ventricular pressure did not change. Heart rate only increased at the lowest left ventricular end-diastolic pressures of 3-4 mmHg, but remained unchanged at higher preload levels. Cardiac output decreased significantly up to -9% at left ventricular end-diastolic pressures of 5-10 mmHg, while left ventricular dp/dtmax showed a consistent reduction of up to -15% at any preload level. Significant reductions were also seen in systolic shortening in the left ventricular major axis (by external measurements -27%, by internal recording -43%). Left ventricular end-diastolic dimensions increased in the major axis by +2% when recorded externally, by +10% when measured internally. Systolic and diastolic changes in the minor axis were not consistent and different in the external and internal recordings.(ABSTRACT TRUNCATED AT 250 WORDS)

CMR reference values for left ventricular volumes, mass, and ejection fraction using computer-aided analysis: the Framingham Heart Study.

PubMed

Chuang, Michael L; Gona, Philimon; Hautvast, Gilion L T F; Salton, Carol J; Breeuwer, Marcel; O'Donnell, Christopher J; Manning, Warren J

2014-04-01

To determine sex-specific reference values for left ventricular (LV) volumes, mass, and ejection fraction (EF) in healthy adults using computer-aided analysis and to examine the effect of age on LV parameters. We examined data from 1494 members of the Framingham Heart Study Offspring cohort, obtained using short-axis stack cine SSFP CMR, identified a healthy reference group (without cardiovascular disease, hypertension, or LV wall motion abnormality) and determined sex-specific upper 95th percentile thresholds for LV volumes and mass, and lower 5th percentile thresholds for EF using computer-assisted border detection. In secondary analyses, we stratified participants by age-decade and tested for linear trend across age groups. The reference group comprised 685 adults (423F; 61 ± 9 years). Men had greater LV volumes and mass, before and after indexation to common measures of body size (all P = 0.001). Women had greater EF (73 ± 6 versus 71 ± 6%; P = 0.0002). LV volumes decreased with greater age in both sexes, even after indexation. Indexed LV mass did not vary with age. LV EF and concentricity increased with greater age in both sexes. We present CMR-derived LV reference values. There are significant age and sex differences in LV volumes, EF, and geometry, whereas mass differs between sexes but not age groups. Copyright © 2013 Wiley Periodicals, Inc.

CMR Reference Values for Left Ventricular Volumes, Mass and Ejection Fraction Using Computer-Aided Analysis: The Framingham Heart Study

PubMed Central

Chuang, Michael L.; Gona, Philimon; Hautvast, Gilion L.T.F.; Salton, Carol J.; Breeuwer, Marcel; O’Donnell, Christopher J.; Manning, Warren J.

2013-01-01

Purpose To determine sex-specific reference values for left ventricular (LV) volumes, mass and ejection fraction (EF) in healthy adults using computer-aided analysis and to examine the effect of age on LV parameters. Methods and Methods We examined data from 1494 members of the Framingham Heart Study Offspring cohort, obtained using short-axis stack cine SSFP CMR, identified a healthy reference group (without cardiovascular disease, hypertension, or LV wall motion abnormality) and determined sex-specific upper 95th percentile thresholds for LV volumes and mass, and lower 5th percentile thresholds for EF using computer-assisted border detection. In secondary analyses we stratified participants by age-decade and tested for linear trend across age groups. Results The reference group comprised 685 adults (423F; 61±9 years). Men had greater LV volumes and mass, before and after indexation to common measures of body size (all p<0.001). Women had greater EF (73±6 vs. 71±6%, p=0.0002). LV volumes decreased with greater age in both sexes, even after indexation. Indexed LV mass did not vary with age. LV EF and concentricity increased with greater age in both sexes. Conclusion We present CMR-derived LV reference values. There are significant age and sex differences in LV volumes, EF and geometry, while mass differs between sexes but not age groups. PMID:24123369

Power loss and right ventricular efficiency in patients after tetralogy of Fallot repair with pulmonary insufficiency: clinical implications.

PubMed

Fogel, Mark A; Sundareswaran, Kartik S; de Zelicourt, Diane; Dasi, Lakshmi P; Pawlowski, Tom; Rome, Jack; Yoganathan, Ajit P

2012-06-01

To quantify right ventricular output power and efficiency and correlate these to ventricular function in patients with repaired tetralogy of Fallot. This might aid in determining the optimal timing for pulmonary valve replacement. We reviewed the cardiac catheterization and magnetic resonance imaging data of 13 patients with tetralogy of Fallot (age, 22 ± 17 years). Using pressure and flow measurements in the main pulmonary artery, cardiac output and regurgitation fraction, right ventricular (RV) power output, loss, and efficiency were calculated. The RV function was evaluated using cardiac magnetic resonance imaging. The RV systolic power was 1.08 ± 0.62 W, with 20.3% ± 8.6% power loss owing to 41% ± 14% pulmonary regurgitation (efficiency, 79.7% ± 8.6%; 0.84 ± 0.73 W), resulting in a net cardiac output of 4.24 ± 1.82 L/min. Power loss correlated significantly with the indexed RV end-diastolic and end-systolic volume (R = 0.78, P = .002 and R = 0.69, P = .009, respectively). The normalized RV power output had a significant negative correlation with RV end-diastolic and end-systolic volumes (both R = -0.87, P = .002 and R = -0.68, P = .023, respectively). A rapid decrease occurred in the RV power capacity with an increasing RV volume, with the curve flattening out at an indexed RV end-diastolic and end-systolic volume threshold of 139 mL/m(2) and 75 mL/m(2), respectively. Significant power loss is present in patients with repaired tetralogy of Fallot and pulmonary regurgitation. A rapid decrease in efficiency occurs with increasing RV volume, suggesting that pulmonary valve replacement should be done before the critical value of 139 mL/m(2) and 75 mL/m(2) for the RV end-diastolic and end-systolic volume, respectively, to preserve RV function. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

23.4% saline decreases brain tissue volume in severe hepatic encephalopathy as assessed by a quantitative computed tomography marker

PubMed Central

Liotta, Eric M; Lizza, Bryan D; Romanova, Anna L; Guth, James C; Berman, Michael D; Carroll, Timothy J; Francis, Brandon; Ganger, Daniel; Ladner, Daniela P; Maas, Matthew B; Naidech, Andrew M

2016-01-01

Objective Cerebral edema is common in severe hepatic encephalopathy and may be life-threatening. Bolus 23.4% hypertonic saline (HTS) improves surveillance neuromonitoring scores, although its mechanism of action is not clearly established. We investigated the hypothesis that bolus HTS decreases cerebral edema in severe hepatic encephalopathy utilizing a quantitative technique to measure brain and CSF volume changes. Design Retrospective analysis of serial computed tomography (CT) scans and clinical data for a case-control series was performed. Setting Intensive care units of a tertiary care hospital. Patients Patients with severe hepatic encephalopathy treated with 23.4% HTS and control patients who did not receive 23.4% HTS. Methods We used clinically obtained CT scans to measure volumes of the ventricles, intracranial CSF, and brain using a previously validated semi-automated technique (Analyze Direct; Overland Park, KS). Volumes before and after 23.4% HTS were compared with Wilcoxon signed-rank test. Associations between total CSF volume, ventricular volume, serum sodium, and Glasgow Coma Scale Scores were assessed using Spearman correlation. Results Eleven patients with 18 administrations of 23.4% HTS met inclusion criteria. Total CSF (median 47.6 [35.1–69.4] to 61.9 [47.7–87.0] mL, p<0.001) and ventricular volumes (median 8.0 [6.9–9.5] to 9.2 [7.8–11.9] mL, p=0.002) increased and Glasgow Coma Scale Scores improved (median 4 [3–6] to 7 [6–9], p=0.008) after 23.4% HTS. In contrast, total CSF and ventricular volumes decreased in untreated control patients. Serum sodium increase was associated with increase in total CSF volume (r=0.83, p<0.001) and change in total CSF volume was associated with ventricular volume change (r=0.86, p<0.001). Conclusions Total CSF and ventricular volumes increased after 23.4% HTS, consistent with a reduction in brain tissue volume. Total CSF and ventricular volume change may be useful quantitative measures to assess cerebral edema in severe hepatic encephalopathy. PMID:26308431

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.

Sequential Right and Left Ventricular Assessment in Posttetralogy of Fallot Patients with Significant Pulmonary Regurgitation.

PubMed

Wijesekera, Vishva A; Raju, Rekha; Precious, Bruce; Berger, Adam J; Kiess, Marla C; Leipsic, Jonathon A; Grewal, Jasmine

2016-12-01

The natural history of right ventricular (RV) and left ventricular (LV) size and function among adults with tetralogy of Fallot (TOF) repair and hemodynamically significant pulmonary regurgitation (PR) is not known. The main aim of this study was to determine changes in RV and LV size and function over time in an adult population with TOF repair and hemodynamically significant pulmonary regurgitation. Forty patients with repaired TOF and hemodynamically significant PR were included. These patients were identified on the basis of having more than one CMR between January 2008 and 2015. Patients with a prosthetic pulmonary valve or any cardiac intervention between CMR studies were excluded. Rate of progression (ROP) of RV dilation was determined for both indexed right ventricular end-systolic volume (RVESVi) and indexed right ventricular end-diastolic volume (RVEDVi), and calculated as the difference between the last and first volumes divided by the number of years between CMR#1 and CMR#2. Subjects were also divided into two groups based on the distribution of the ROP of RV dilation: Group I-rapid ROP (>50th percentile) and Group II-slower ROP (≤50th percentile). The interval between CMR#1 and CMR#2 was 3.9 ± 1.7 years (range 1-8 years). We did find a significant change in RVEDVi and RVESVi over this time period, although the magnitude of change was small. Nine patients (23%) had a reduction in right ventricular ejection fraction (RVEF) by greater than 5%, 13 patients (33%) had an increase in RVEDVi by greater than 10 mL/m 2 and seven patients (18%) had an increase in RVESVi by greater than 10 mL/m 2 . Median ROP for RVEDVi was 1.8 (range -10.4 to 21.8) mL/(m 2 year); RVESVi 1.1 (range -5.8 to 24.5) mL/(m 2 year) and RVEF -0.5 (range -8 to 4)%/year. Patients with a rapid ROP had significantly larger RV volumes at the time of CMR#1 and lower RVEF as compared to the slow ROP group. There was no overall significant change in LVEDVi, LVESVi, or LVEF over this time period. We have demonstrated, in a small population of patients with hemodynamically significant PR, that there is a small increase in RV volumes and decrease in RVEF over a mean 4-year period. We believe it to be reasonable practice to perform CMR at least every 4 years in asymptomatic patients with repaired TOF and hemodynamically significant PR. We found that LV volumes and function remained stable during the study period, suggesting that significant progressive LV changes are less likely to occur over a shorter time period. Our results inform a safe standardized approach to monitoring adults with hemodynamically significant PR post TOF repair and assist in planning allocation of this expensive and limited resource. © 2016 Wiley Periodicals, Inc.

Minimal role of nitric oxide in basal coronary flow regulation and cardiac energetics of blood-perfused isolated canine heart.

PubMed Central

Saeki, A; Recchia, F A; Senzaki, H; Kass, D A

1996-01-01

1. The role of nitric oxide (NO) in the regulation of basal coronary perfusion and ventricular chamber energetics was studied in isovolumetrically contracting isolated blood-perfused canine hearts. Hearts were cross-perfused by a donor animal prior to isolation, and chamber volume controlled by a servo-pump. Coronary sinus flow and arterial-coronary sinus oxygen difference were measured to determine energetic efficiency. 2. NO synthase (NOS) was competitively inhibited by NG-monomethyl-L-arginine (L-NMMA; 0.5 mg kg-1, intracoronary), resulting in a reduction of acetylcholine (50 micrograms min-1)-induced flow augmentation from 143 to 62% (P < 0.001). 3. NOS inhibition had no significant effect on basal coronary flow. Coronary pressure-flow relationships were determined at a constant cardiac workload by varying mean perfusion pressure between 20 and 150 mmHg. Neither the shape of the relationship, nor the low-pressure value at which flow regulation was substantially diminished were altered by NOS inhibition. 4. Myocardial efficiency was assessed by the relationship between myocardial oxygen consumption and total pressure-volume area (PVA), with cavity volume altered to generate varying PVAs. This relative load-independent measure of energetic efficiency was minimally altered by NOS inhibition. 5. These results contrast with isolated crystalloid-perfused heart experiments and suggest that in hearts with highly controlled ventricular loading and whole-blood perfusion, effects of basal NO production on coronary perfusion and left ventricular energetics are minimal. PMID:8866868

Reduced left ventricular filling following blood volume extraction does not result in compensatory augmentation of cardiac mechanics.

PubMed

Lord, Rachel; MacLeod, David; George, Keith; Oxborough, David; Shave, Rob; Stembridge, Mike

2018-04-01

What is the central question of this study? A reduction in left ventricular (LV) filling, and concomitant increase in heart rate, augments LV mechanics to maintain stroke volume (SV); however, the impact of reduced LV filling in isolation on SV and LV mechanics is currently unknown. What is the main finding and its importance? An isolated decrease in LV filling did not provoke a compensatory increase in mechanics to maintain SV; in contrast, LV mechanics and SV were reduced. These data indicate that when LV filling is reduced without changes in heart rate, LV mechanics do not compensate to maintain SV. An acute non-invasive reduction in preload has been shown to augment cardiac mechanics to maintain stroke volume and cardiac output. Such interventions induce concomitant changes in heart rate, whereas blood volume extraction reduces preload without changes in heart rate. Therefore, the purpose of this study was to determine whether a preload reduction in isolation resulted in augmented stroke volume achieved via enhanced cardiac mechanics. Nine healthy volunteers (four female, age 29 ± 11 years) underwent echocardiography for the assessment of left ventricular (LV) volumes and mechanics in a supine position at baseline and end extraction after the controlled removal of 25% of total blood volume (1062 ± 342 ml). Arterial blood pressure was monitored continuously by a pressure transducer attached to an indwelling radial artery catheter. Heart rate and total peripheral resistance were unchanged from baseline to end extraction, but systolic blood pressure was reduced (from 148 to 127 mmHg). From baseline to end extraction there were significant reductions in left ventricular end-diastolic volume (from 89 to 71 ml) and stroke volume (from 56 to 37 ml); however, there was no change in LV twist, basal or apical rotation. In contrast, LV longitudinal strain (from -20 to -17%) and basal circumferential strain (from -22 to -19%) were significantly reduced from baseline to end extraction. In conclusion, a reduction in preload during blood volume extraction does not result in compensatory changes in stroke volume or cardiac mechanics. Our data suggest that LV strain is dependent on LV filling and consequent geometry, whereas LV twist could be mediated by heart rate. © 2018 The Authors. Experimental Physiology © 2018 The Physiological Society.

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

Massie, B.; Kramer, B.L.; Topic, N.

Although the resting hemodynamic effects of captopril in congestive heart failure are known, little information is available about the hemodynamic response to captopril during exercise or about changes in noninvasive measurements of the size and function of both ventricles. In this study, 14 stable New York Heart Association class III patients were given 25 mg of oral captopril. Rest and exercise hemodynamic measurements and blood pool scintigrams were performed simultaneously before and 90 minutes after captopril. The radionuclide studies were analyzed for left and right ventricular end-diastolic volumes, end-systolic volumes, ejection fractions and pulmonary blood volume. The primary beneficial responsesmore » at rest were decreases in left and right ventricular end-diastolic volumes from 388 +/- 81 to 350 +/- 77 ml and from 52 +/- 26 to 43 +/- 20 volume units, respectively, and in their corresponding filling pressures, from 24 +/- 10 to 17 +/- 9 mm Hg and 10 +/- 5 to 6 +/- 5 mm Hg. Although stroke volume did not increase significantly, both left and right ventricular ejection fractions increased slightly, from 19 +/- 6% to 22+/- 5% and from 25 +/- 9% to 29 +/- 11%, respectively. During exercise, similar changes were noted in both hemodynamic and radionuclide indexes. This, in patients with moderate symptomatic limitation from chronic heart failure, captopril predominantly reduces ventricular volume and filling pressure, with a less significant effect on cardiac output. These effects persist during exercise, when systemic vascular resistance is already very low. Radionuclide techniques are valuable in assessing the drug effect in these subjects, particularly when ventricular volumes are also measured.« less

Innervation of Ventricular and Periventricular Brain Compartments

PubMed Central

Leak, Rehana K.; Moore, Robert Y.

2012-01-01

Synaptic transmission is divided into two broad categories on the basis of the distance over which neurotransmitters travel. Wiring transmission is the release of transmitter into synaptic clefts in close apposition to receptors. Volume transmission is the release of transmitters or modulators over varying distances before interacting with receptors. One case of volume transmission over potentially long distances involves release into cerebrospinal fluid (CSF). The CSF contains neuroactive substances that affect brain function and range in size from small molecule transmitters to peptides and large proteins. CSF-contacting neurons are a well-known and universal feature of non-mammalian vertebrates, but only supra- and subependymal serotonergic plexuses are a commonly studied feature in mammals. The origin of most other neuroactive substances in CSF is unknown. In order to determine which brain regions communicate with CSF, we describe the distribution of retrograde neuronal labeling in the rat brain following ventricular injection of Cholera toxin, β subunit (CTβ), a tracer frequently used in brain circuit analysis. Within 15 to 30 minutes following intraventricular injection, there is only diffuse, non-specific staining adjacent to the ventricular surface. Within 2 to 10 days, however, there is extensive labeling of neuronal perikarya in specific nuclear groups in the telencephalon, thalamus, hypothalamus and brainstem, many at a considerable distance from the ventricles. These observations support the view that ventricular CSF is a significant channel for volume transmission and identifies those brain regions most likely to be involved in this process. PMID:22575559

The role of elastic restoring forces in right-ventricular filling

PubMed Central

Pérez Del Villar, Candelas; Bermejo, Javier; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Antoranz, J. Carlos; Desco, M. Mar; Ortuño, Juan E.; Barrio, Alicia; Mombiela, Teresa; Yotti, Raquel; Ledesma-Carbayo, Maria J.; Del Álamo, Juan C.; Fernández-Avilés, Francisco

2015-01-01

Aims The physiological determinants of RV diastolic function remain poorly understood. We aimed to quantify the contribution of elastic recoil to RV filling and determine its sensitivity to interventricular interaction. Methods and results High-fidelity pressure–volume loops and simultaneous 3-dimensional ultrasound sequences were obtained in 13 pigs undergoing inotropic modulation, volume overload, and acute pressure overload induced by endotoxin infusion. Using a validated method, we isolated elastic restoring forces from ongoing relaxation using conventional pressure–volume data. The RV contracted below the equilibrium volume in >75% of the data sets. Consequently, elastic recoil generated strong sub-atmospheric passive pressure at the onset of diastole [−3 (−4 to −2) mmHg at baseline]. Stronger restoring suction pressure was related to a shorter isovolumic relaxation period, a higher rapid filling fraction, and lower atrial pressures (all P < 0.05). Restoring forces were mostly determined by the position of operating volumes around the equilibrium volume. By this mechanism, the negative inotropic effect of beta-blockade reduced and sometimes abolished restoring forces. During acute pressure overload, restoring forces initially decreased, but recovered at advanced stages. This biphasic response was related to alterations of septal curvature induced by changes in the diastolic LV–RV pressure balance. The constant of elastic recoil was closely related to the constant of passive stiffness (R = 0.69). Conclusion The RV works as a suction pump, exploiting contraction energy to facilitate filling by means of strong elastic recoil. Restoring forces are influenced by the inotropic state and RV conformational changes mediated by direct ventricular interdependence. PMID:25691537

Effect of preload reduction by hemodialysis on left atrial volume and echocardiographic Doppler parameters in patients with end-stage renal disease.

PubMed

Barberato, Silvio H; Mantilla, Diego E V; Misocami, M Arcio; Gonçalves, Simone M; Bignelli, Alexandre T; Riella, Miguel C; Pecoits-Filho, Roberto

2004-11-01

Left atrial (LA) volume has been proposed as a less preload-dependent parameter of diastolic function than Doppler mitral inflow. We hypothesize that in the absence of mitral regurgitation and atrial fibrilation, LA enlargement could be a more practical (and relatively preload-independent) method for the evaluation of left ventricular diastolic function. The aim of the present study was to determine the effects of preload reduction by hemodialysis on LA volume.

Integration of mechanical, structural and electrical imaging to understand response to cardiac resynchronization therapy.

PubMed

Silva, Etelvino; Bijnens, Bart; Berruezo, Antonio; Mont, Lluis; Doltra, Adelina; Andreu, David; Brugada, Josep; Sitges, Marta

2014-10-01

There is extensive controversy exists on whether cardiac resynchronization therapy corrects electrical or mechanical asynchrony. The aim of this study was to determine if there is a correlation between electrical and mechanical sequences and if myocardial scar has any relevant impact. Six patients with normal left ventricular function and 12 patients with left ventricular dysfunction and left bundle branch block, treated with cardiac resynchronization therapy, were studied. Real-time three-dimensional echocardiography and electroanatomical mapping were performed in all patients and, where applicable, before and after therapy. Magnetic resonance was performed for evaluation of myocardial scar. Images were postprocessed and mechanical and electrical activation sequences were defined and time differences between the first and last ventricular segment to be activated were determined. Response to therapy was defined as a reduction in left ventricular end-systolic volume ≥ 15% after 12 months of follow-up. Good correlation between electrical and mechanical timings was found in patients with normal left ventricular function (r(2) = 0.88; P = .005) but not in those with left ventricular dysfunction (r(2) = 0.02; P = not significant). After therapy, both timings and sequences were modified and improved, except in those with myocardial scar. Despite a close electromechanical relationship in normal left ventricular function, there is no significant correlation in patients with dysfunction. Although resynchronization therapy improves this correlation, the changes in electrical activation may not yield similar changes in left ventricular mechanics particularly depending on the underlying myocardial substrate. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Effects of milrinone and epinephrine or dopamine on biventricular function and hemodynamics in an animal model with right ventricular failure after pulmonary artery banding.

PubMed

Hyldebrandt, Janus Adler; Sivén, Eleonora; Agger, Peter; Frederiksen, Christian Alcaraz; Heiberg, Johan; Wemmelund, Kristian Borup; Ravn, Hanne Berg

2015-07-01

Right ventricular (RV) failure due to chronic pressure overload is a main determinant of outcome in congenital heart disease. Medical management is challenging because not only contractility but also the interventricular relationship is important for increasing cardiac output. This study evaluated the effect of milrinone alone and in combination with epinephrine or dopamine on hemodynamics, ventricular performance, and the interventricular relationship. RV failure was induced in 21 Danish landrace pigs by pulmonary artery banding. After 10 wk, animals were reexamined using biventricular pressure-volume conductance catheters. The maximum pressure in the RV increased by 113% (P < 0.0001) and end-diastolic volume by 43% (P < 0.002), while left ventricular (LV) pressure simultaneously decreased (P = 0.006). Concomitantly, mean arterial pressure (MAP; -16%, P = 0.01), cardiac index (CI; -23%, P < 0.0001), and mixed venous oxygen saturation (SvO2 ; -40%, P < 0.0001) decreased. Milrinone increased CI (11%, P = 0.008) and heart rate (HR; 21%, P < 0.0001). Stroke volume index (SVI) decreased (7%, P = 0.03), although RV contractility was improved. The addition of either epinephrine or dopamine further increased CI and HR in a dose-dependent manner but without any significant differences between the two interventions. A more pronounced increase in biventricular contractility was observed in the dopamine-treated animals. LV volume was reduced in both the dopamine and epinephrine groups with increasing doses In the failing pressure overloaded RV, milrinone improved CI and increased contractility. Albeit additional dose-dependent effects of both epinephrine and dopamine on CI and contractility, neither of the interventions improved SVI due to reduced filling of the LV. Copyright © 2015 the American Physiological Society.

Non-invasive detection and monitoring of experimental hydrocephalus with distortion product otoacoustic emissions.

PubMed

Ezerarslan, Hande; Beriat, Güçlü Kaan; Nurhat, Raziye Handan; Kazancı, Burak; Çelikkan, Ferda Topal; Sabuncuoğlu, Bizden; Sabuncuoğlu, Hakan

2016-08-01

We aimed to find out the effects of short term and long term hydrocephalus and intracranial ventricular volume changes on cochlear functions by using distortion product otoacoustic emission (DPOAE) in experimental hydrocephalus rat models for the first time in literature. This study was performed with 48 healthy, adult (8 weeks old), Sprague-Dawley rats which weighed between 200 and 240g. Six groups were formed in this study: short term control, short term sham, short term hydrocephalus, long term control, long term sham and long term hydrocephalus groups. Each group contained eight rats. Short term period was 4 weeks and long term period was 8 weeks after the study started. At the end of these periods, DPOAE measurements were performed and then rats were sacrificed to determine ventricular volumes. DPOAE values at all frequencies were significantly decreased in the short term hydrocephalus group when compared to the short term control and short term sham groups. DPOAE values at all frequencies were significantly decreased in the long term hydrocephalus group when compared to the long term control and long term sham groups. Besides, long term sham group which had higher ventricular volumes than long term control group also had lower DPOAE measurements. Significant associations were present between DPOAE measurements and ventricular volumes in hydrocephalus models. The functional disturbances in cochlear functions due to hydrocephalus have been demonstrated with DPOAE measurements in this study. DPOAE measurements may be thought as an easily applicable non-invasive method in detection and follow-up of patients with hydrocephalus. Our findings should be supported with clinical studies in humans. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Quantification of right ventricular volume in dogs: a comparative study between three-dimensional echocardiography and computed tomography with the reference method magnetic resonance imaging.

PubMed

Sieslack, Anne K; Dziallas, Peter; Nolte, Ingo; Wefstaedt, Patrick; Hungerbühler, Stephan O

2014-10-12

Right ventricular (RV) volume and function are important diagnostic and prognostic factors in dogs with primary or secondary right-sided heart failure. The complex shape of the right ventricle and its retrosternal position make the quantification of its volume difficult. For that reason, only few studies exist, which deal with the determination of RV volume parameters. In human medicine cardiac magnetic resonance imaging (CMRI) is considered to be the reference technique for RV volumetric measurement (Nat Rev Cardiol 7(10):551-563, 2010), but cardiac computed tomography (CCT) and three-dimensional echocardiography (3DE) are other non-invasive methods feasible for RV volume quantification. The purpose of this study was the comparison of 3DE and CCT with CMRI, the gold standard for RV volumetric quantification. 3DE showed significant lower and CCT significant higher right ventricular volumes than CMRI. Both techniques showed very good correlations (R > 0.8) with CMRI for the volumetric parameters end-diastolic volume (EDV) and end-systolic volume (ESV). Ejection fraction (EF) and stroke volume (SV) were not different when considering CCT and CMRI, whereas 3DE showed a significant higher EF and lower SV than CMRI. The 3DE values showed excellent intra-observer variability (<3%) and still acceptable inter-observer variability (<13%). CCT provides an accurate image quality of the right ventricle with comparable results to the reference method CMRI. CCT overestimates the RV volumes; therefore, it is not an interchangeable method, having the disadvantage as well of needing general anaesthesia. 3DE underestimated the RV-Volumes, which could be explained by the worse image resolution. The excellent correlation between the methods indicates a close relationship between 3DE and CMRI although not directly comparable. 3DE is a promising technique for RV volumetric quantification, but further studies in awake dogs and dogs with heart disease are necessary to evaluate its usefulness in veterinary cardiology.

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.

Relationship of carotid arterial functional and structural changes to left atrial volume in untreated hypertension.

PubMed

Jaroch, Joanna; Rzyczkowska, Barbara; Bociąga, Zbigniew; Vriz, Olga; Driussi, Caterina; Loboz-Rudnicka, Maria; Dudek, Krzysztof; Łoboz-Grudzień, Krystyna

2016-04-01

The contribution of arterial functional and structural changes to left ventricular (LV) diastolic dysfunction has been the area of recent research. There are some studies on the relationship between arterial stiffness (a.s.) and left atrial (LA) remodelling as a marker of diastolic burden. Little is known about the association of arterial structural changes and LA remodelling in hypertension (H). The aim of this study was to examine the relationship between carotid a.s. and intima-media thickness (IMT) and LA volume in subjects with H. The study included 245 previously untreated hypertensives (166 women and 79 men, mean age 53.7 ± 11.8 years). Each patient was subjected to echocardiography with measurement of LA volume, evaluation of left ventricular hypertrophy (LVH) and LV systolic/diastolic function indices, integrated assessment of carotid IMT and echo-tracking of a.s. and wave reflection parameters. Univariate regression analysis revealed significant correlations between indexed LA volume and selected clinical characteristics, echocardiographic indices of LVH and LV diastolic/systolic function and a.s./wave reflection parameters. The following parameters were identified as independent determinants of indexed LA volume on multivariate regression analysis: diastolic blood pressure (beta = -0.229, P < 0.001), left ventricular mass index (LVMI; beta = 0.258, P < 0.001), E/e’ index (ratio of early mitral flow wave velocity – E to early diastolic mitral annular velocity – e’; beta = 0.266, P = 0.001), augmentation index (AI; beta = 0.143, P = 0.008) and body mass index (BMI; beta = 0.132, P = 0.017). No correlations between indexed LA volume and IMT were found. There is a significant relationship between carotid arterial stiffness but not intima-media thickness and LA volume in patients with untreated hypertension.

Spaceflight-induced changes in white matter hyperintensity burden in astronauts.

PubMed

Alperin, Noam; Bagci, Ahmet M; Lee, Sang H

2017-11-21

To assess the effect of weightlessness and the respective roles of CSF and vascular fluid on changes in white matter hyperintensity (WMH) burden in astronauts. We analyzed prespaceflight and postspaceflight brain MRI scans from 17 astronauts, 10 who flew a long-duration mission on the International Space Station (ISS) and 7 who flew a short-duration mission on the Space Shuttle. Automated analysis methods were used to determine preflight to postflight changes in periventricular and deep WMH, CSF, and brain tissue volumes in fluid-attenuated inversion recovery and high-resolution 3-dimensional T1-weighted imaging. Differences between cohorts and associations between individual measures were assessed. The short-term reversibility of the identified preflight to postflight changes was tested in a subcohort of 5 long-duration astronauts who had a second postflight MRI scan 1 month after the first postflight scan. Significant preflight to postflight changes were measured only in the long-duration cohort and included only the periventricular WMH and ventricular CSF volumes. Changes in deep WMH and brain tissue volumes were not significant in either cohort. The increase in periventricular WMH volume was significantly associated with an increase in ventricular CSF volume (ρ = 0.63, p = 0.008). A partial reversal of these increases was observed in the long-duration subcohort with a 1-month follow-up scan. Long-duration exposure to microgravity is associated with an increase in periventricular WMH in astronauts. This increase was linked to an increase in ventricular CSF volume documented in ISS astronauts. There was no associated change in or abnormal levels of WMH volumes in deep white matter as reported in U-2 high-altitude pilots. © 2017 American Academy of Neurology.

Factors confounding impedance catheter volume measurements in vitro.

PubMed

Bielefeld, M R; Cabreriza, S E; Spotnitz, H M

1993-06-01

The impedance catheter allows continuous measurement of ventricular volume. External influences have been described as causing parallel shifts in impedance-measured volumes; however, factors affecting impedance measurements in a nonparallel manner have not been fully characterized. Accordingly, an impedance catheter was placed inside a latex balloon into which known volumes of normal saline solution were injected. Conductive and nonconductive materials were individually placed within the balloon. Impedance was measured with materials touching (T) or not touching (NT) the catheter. Impedance-measured volumes were plotted versus actual volumes. Compared with the line of identity (LID), a statistical difference (p < 0.05) was found in the slopes in the presence of metallic objects only. These included a pacing lead (T, NT) (mT = 1.32m mNT = 1.29 versus mLID = 1.00), titanium (T) (mT = 1.68 versus mLID = 1.00), and aluminum (NT) (mNT = 0.72 versus mLID = 1.00). These changes in slope indicate nonparallel effects on impedance that confound the ability of the impedance catheter to determine volumes in vitro. These observations imply that serial calibration of both the slope constant (alpha) and the intercept (parallel conductance) of impedance may be necessary for in vivo measurements of ventricular volume based on impedance in the presence of metallic objects.

Percutaneous closure of atrial septal defects leads to normalisation of atrial and ventricular volumes

PubMed Central

Teo, Karen SL; Dundon, Benjamin K; Molaee, Payman; Williams, Kerry F; Carbone, Angelo; Brown, Michael A; Worthley, Matthew I; Disney, Patrick J; Sanders, Prashanthan; Worthley, Stephen G

2008-01-01

Background Percutaneous closure of atrial septal defects (ASDs) should potentially reduce right heart volumes by removing left-to-right shunting. Due to ventricular interdependence, this may be associated with impaired left ventricular filling and potentially function. Furthermore, atrial changes post-ASD closure have been poorly understood and may be important for understanding risk of atrial arrhythmia post-ASD closure. Cardiovascular magnetic resonance (CMR) is an accurate and reproducible imaging modality for the assessment of cardiac function and volumes. We assessed cardiac volumes pre- and post-percutaneous ASD closure using CMR. Methods Consecutive patients (n = 23) underwent CMR pre- and 6 months post-ASD closure. Steady state free precession cine CMR was performed using contiguous slices in both short and long axis views through the ASD. Data was collected for assessment of left and right atrial, ventricular end diastolic volumes (EDV) and end systolic volumes (ESV). Data is presented as mean ± SD, volumes as mL, and paired t-testing performed between groups. Statistical significance was taken as p < 0.05. Results There was a significant reduction in right ventricular volumes at 6 months post-ASD closure (RVEDV: 208.7 ± 76.7 vs. 140.6 ± 60.4 mL, p < 0.0001) and RVEF was significantly increased (RVEF 35.5 ± 15.5 vs. 42.0 ± 15.2%, p = 0.025). There was a significant increase in the left ventricular volumes (LVEDV 84.8 ± 32.3 vs. 106.3 ± 38.1 mL, p = 0.003 and LVESV 37.4 ± 20.9 vs. 46.8 ± 18.5 mL, p = 0.016). However, there was no significant difference in LVEF and LV mass post-ASD closure. There was a significant reduction in right atrial volumes at 6 months post-ASD closure (pre-closure 110.5 ± 55.7 vs. post-closure 90.7 ± 69.3 mL, p = 0.019). Although there was a trend to a decrease in left atrial volumes post-ASD closure, this was not statistically significant (84.5 ± 34.8 mL to 81.8 ± 44.2 mL, p = NS). Conclusion ASD closure leads to normalisation of ventricular volumes and also a reduction in right atrial volume. Further follow-up is required to assess how this predicts outcomes such as risk of atrial arrhythmias after such procedures. PMID:19040763

Mitral regurgitation: anatomy is destiny.

PubMed

Athanasuleas, Constantine L; Stanley, Alfred W H; Buckberg, Gerald D

2018-04-26

Mitral regurgitation (MR) occurs when any of the valve and ventricular mitral apparatus components are disturbed. As MR progresses, left ventricular remodelling occurs, ultimately causing heart failure when the enlarging left ventricle (LV) loses its conical shape and becomes globular. Heart failure and lethal ventricular arrhythmias may develop if the left ventricular end-systolic volume index exceeds 55 ml/m2. These adverse changes persist despite satisfactory correction of the annular component of MR. Our goal was to describe this process and summarize evolving interventions that reduce the volume of the left ventricle and rebuild its elliptical shape. This 'valve/ventricle' approach addresses the spherical ventricular culprit and offsets the limits of treating MR by correcting only its annular component.

Refractory Hypertension Is not Attributable to Intravascular Fluid Retention as Determined by Intracardiac Volumes.

PubMed

Velasco, Alejandro; Siddiqui, Mohammed; Kreps, Eric; Kolakalapudi, Pavani; Dudenbostel, Tanja; Arora, Garima; Judd, Eric K; Prabhu, Sumanth D; Lloyd, Steven G; Oparil, Suzanne; Calhoun, David A

2018-06-04

Refractory hypertension (RfHTN) is an extreme phenotype of antihypertensive treatment failure defined as lack of blood pressure control with ≥5 medications, including a long-acting thiazide and a mineralocorticoid receptor antagonist. RfHTN is a subgroup of resistant hypertension (RHTN), which is defined as blood pressure >135/85 mm Hg with ≥3 antihypertensive medications, including a diuretic. RHTN is generally attributed to persistent intravascular fluid retention. It is unknown whether alternative mechanisms are operative in RfHTN. Our objective was to determine whether RfHTN is characterized by persistent fluid retention, indexed by greater intracardiac volumes determined by cardiac magnetic resonance when compared with controlled RHTN patients. Consecutive patients evaluated in our institution with RfHTN and controlled RHTN were prospectively enrolled. Exclusion criteria included advanced chronic kidney disease and masked or white coat hypertension. All enrolled patients underwent biochemical testing and cardiac magnetic resonance. The RfHTN group (n=24) was younger (mean age, 51.7±8.9 versus 60.6±11.5 years; P =0.003) and had a greater proportion of women (75.0% versus 43%; P =0.02) compared with the controlled RHTN group (n=30). RfHTN patients had a greater left ventricular mass index (88.3±35.0 versus 54.6±12.5 g/m 2 ; P <0.001), posterior wall thickness (10.1±3.1 versus 7.7±1.5 mm; P =0.001), and septal wall thickness (14.5±3.8 versus 10.0±2.2 mm; P <0.001). There was no difference in B-type natriuretic peptide levels and left atrial or ventricular volumes. Diastolic dysfunction was noted in RfHTN. Our findings demonstrate greater left ventricular hypertrophy without chamber enlargement in RfHTN, suggesting that antihypertensive treatment failure is not attributable to intravascular volume retention. © 2018 American Heart Association, Inc.

Three-dimensional echocardiographic measurements using automated quantification software for big data processing.

PubMed

Feng, Cheng; Chen, Lixin; Li, Jian; Wang, Jiangtao; Dong, Fajin; Xu, Jinfeng

2017-01-01

To compare a full-automated software to quantify 3D transthoracic echocardiography namely, 3DE-HM (three-dimensional echocardiography HeartModel, Philips Healthcare) with the traditional manual quantitative method (3DE-manual) for assessing volumes of left atrial and ventricular volumes, and left ventricular ejection fraction (LVEF). 3D full volume images acquired from 156 subjects were collected and divided into 3 groups, which include 70 normal control cases (Group A), 17 patients with left ventricular remodeling after acute myocardial infarction (AMI) (Group B), and 69 patients with left atrial remodeling secondary to hypertension (Group C). The 3DE-HM method was used to quantify left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left atrial end-systolic volume (LAESV), and left ventricular ejection fraction (LVEF), respectively. The results were compared with those obtained with the 3DE-manual method for correlation and consistency analyses. The reproducibility of the 3DE-HM method was also evaluated. There was a high correlation between LVEDV, LVESV, LAESV and LVEF values obtained with the 3DE-HM method and those obtained using the 3DE-manual method (r = 0.72 to 0.97). The correlation was strongest for Group B, patients with left ventricular remodeling post-AMI also demonstrated the greatest degree of morphologic changes. There was a significant difference in all parameters measured with the 3DE-HM method in different groups (P < 0.05). The difference in the measurements of LVEDV and LVESV between the two methods was greatest in patients in Group B compared with patients with hypertension-induced left ventricular remodeling (Group C) and in normal controls (Group A) (P < 0.05). Lastly, the difference in the measurement of LAESV between the two methods was greater in patients with hypertension-induced left ventricular remodeling (Group C) than that in the control group (Group A) (P < 0.05). The post-processing time of the 3DE-HM data was significantly shorter than that using the 3DE-manual method (P < 0.05). There was no significant variability in repeated measurements at different time points using the 3DE-HM method either between subjects in different groups or within the same subject. 3DE-HM is a quick and feasible method for left ventricular quantification and is clinically applicable for evaluating patients with left atrial and left ventricular remodeling.

Right heart overload contributes to cardiac natriuretic hormone elevation in patients with heart failure.

PubMed

Passino, Claudio; Maria Sironi, Anna; Favilli, Brunella; Poletti, Roberta; Prontera, Concetta; Ripoli, Andrea; Lombardi, Massimo; Emdin, Michele

2005-09-15

Atrial and brain natriuretic peptides (ANP and BNP) plasma concentration increases and holds a prognostic significance in patients with left ventricular dysfunction. We assessed the hypothesis that right ventricular (RV) overload might significantly contribute to plasma elevation of cardiac natriuretic hormones in patients with heart failure. Forty-one patients with cardiomyopathy and depressed left ventricular (LV) function (ejection fraction, EF, <40%), underwent cardiac magnetic resonance imaging (MRI) and resting plasma determination of ANP and BNP. Nineteen healthy subjects were also studied as control group. Ventricular volumes and function were assessed by MRI. In the group of patients, LVEF was 22.6+/-1.2% (controls: 61.2+/-1.3%, P<0.001, mean+/-S.E.M.), while RVEF was 48.2+/-2.5% (controls: 66.7+/-1.6%, P<0.001); LV and RV end diastolic/systolic volumes, corrected by body surface area, were 143+/-7/114+/-7 ml/m2 (controls 70+/-3/27+/-2 ml/m2, both P<0.001) and 66+/-3/37+/-4 ml/m2 (controls: 63+/-4/21+/-2 ml/m2, P<0.01 only for end-systolic volume). BNP plasma value was on average 324+/-39 pg/ml (range: 23-1280, controls 10+/-2 pg/ml), ANP value was 144+/-17 pg/ml (range: 26-534, controls 15+/-1 pg/ml). BNP positively correlated with either end-diastolic or end-systolic RV volume in patients, less with LV systolic, and not with LV diastolic volume. Moreover, a significant negative correlation was observed between BNP and either LVEF or RVEF. Conversely, ANP showed a significant correlation only with end-systolic RV volume and with both RVEF and LVEF. When multivariate stepwise linear regression analysis was applied LVEF resulted the only independent predictor for ANP plasma values (R=0.591, P<0.001), while LVEF and RV end-diastolic volume for BNP (R=0.881, P<0.001, and R=0.881, P=0.035, respectively). Right heart overload contributes independently to plasma elevation of natriuretic peptides. RV involvement, which is known to independently worsen prognosis in patients with cardiomyopathy, might contribute to their established prognostic power, inducing compensatory secretion of plasma cardiac natriuretic hormones.

Effects of increasing left ventricular filling pressure in patients with acute myocardial infarction

PubMed Central

Russell, Richard O.; Rackley, Charles E.; Pombo, Jaoquin; Hunt, David; Potanin, Constantine; Dodge, Harold T.

1970-01-01

Left ventricular performance in 19 patients with acute myocardial infarction has been evaluated by measuring left ventricular response in terms of cardiac output, stroke volume, work, and power to progressive elevation of filling pressure accomplished by progressive expansion of blood volume with rapid infusion of low molecular weight dextran. Such infusion can elevate the cardiac output, stroke volume, work, and power and thus delineate the function of the left ventricle by Frank-Starling function curves. Left ventricular filling pressure in the range of 20-24 mm Hg was associated with the peak of the curves and when the filling pressure exceeded this range, the curves became flattened or decreased. An increase in cardiac output could be maintained for 4 or more hr. Patients with a flattened function curve had a high mortality in the ensuing 8 wk. The function curve showed improvement in myocardial function during the early convalescence. When left ventricular filling pressure is monitored directly or as pulmonary artery end-diastolic pressure, low molecular weight dextran provides a method for assessment of left ventricular function. Images PMID:5431663

Epinephrine and left atrial and left ventricular diastolic function decrease in normal subjects.

PubMed

Fuenmayor, Abdel J; Solórzano, Moisés I; Gómez, Luisangelly

2016-10-01

We assessed the effect of epinephrine over left atrial and left ventricular diastolic function in subjects without structural heart disease. Twenty-seven, 34.6±17.2year-old patients without structural heart disease were included. Intravenous epinephrine (50 to 100ng/kg/min) was infused. Left atrial and ventricular functions were evaluated by means of echocardiography before and during the epinephrine infusion. No complications were observed. Significant increases in heart rate and systolic blood pressure were recorded. Both left atrial (minimal and maximal) volumes increased but increase in the minimal volume was more pronounced, and the ejection fraction diminished. Left atrial expansion index decreased and the fraction of left ventricular inflow volume resulting from atrial contraction increased. Two patients displayed abnormal left ventricular diastolic function. During epinephrine infusion, E/A and e' decreased, and isovolumetric relaxation time increased. In this group of young adults without structural heart disease, epinephrine infusion was safe, did not produce any complications, and induced a small but significant decrease in left atrial function and left ventricular diastolic function. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Direct volume estimation without segmentation

NASA Astrophysics Data System (ADS)

Zhen, X.; Wang, Z.; Islam, A.; Bhaduri, M.; Chan, I.; Li, S.

2015-03-01

Volume estimation plays an important role in clinical diagnosis. For example, cardiac ventricular volumes including left ventricle (LV) and right ventricle (RV) are important clinical indicators of cardiac functions. Accurate and automatic estimation of the ventricular volumes is essential to the assessment of cardiac functions and diagnosis of heart diseases. Conventional methods are dependent on an intermediate segmentation step which is obtained either manually or automatically. However, manual segmentation is extremely time-consuming, subjective and highly non-reproducible; automatic segmentation is still challenging, computationally expensive, and completely unsolved for the RV. Towards accurate and efficient direct volume estimation, our group has been researching on learning based methods without segmentation by leveraging state-of-the-art machine learning techniques. Our direct estimation methods remove the accessional step of segmentation and can naturally deal with various volume estimation tasks. Moreover, they are extremely flexible to be used for volume estimation of either joint bi-ventricles (LV and RV) or individual LV/RV. We comparatively study the performance of direct methods on cardiac ventricular volume estimation by comparing with segmentation based methods. Experimental results show that direct estimation methods provide more accurate estimation of cardiac ventricular volumes than segmentation based methods. This indicates that direct estimation methods not only provide a convenient and mature clinical tool for cardiac volume estimation but also enables diagnosis of cardiac diseases to be conducted in a more efficient and reliable way.

Electrocardiograph-gated single photon emission computed tomography radionuclide angiography presents good interstudy reproducibility for the quantification of global systolic right ventricular function.

PubMed

Daou, Doumit; Coaguila, Carlos; Vilain, Didier

2007-05-01

Electrocardiograph-gated single photon emission computed tomography (SPECT) radionuclide angiography provides accurate measurement of right ventricular ejection fraction and end-diastolic and end-systolic volumes. In this study, we report the interstudy precision and reliability of SPECT radionuclide angiography for the measurement of global systolic right ventricular function using two, three-dimensional volume processing methods (SPECT-QBS, SPECT-35%). These were compared with equilibrium planar radionuclide angiography. Ten patients with chronic coronary artery disease having two SPECT and planar radionuclide angiography acquisitions were included. For the right ventricular ejection fraction, end-diastolic volume and end-systolic volume, the interstudy precision and reliability were better with SPECT-35% than with SPECT-QBS. The sample sizes needed to objectify a change in right ventricular volumes or ejection fraction were lower with SPECT-35% than with SPECT-QBS. The interstudy precision and reliability of SPECT-35% and SPECT-QBS for the right ventricle were better than those of equilibrium planar radionuclide angiography, but poorer than those previously reported for the left ventricle with SPECT radionuclide angiography on the same population. SPECT-35% and SPECT-QBS present good interstudy precision and reliability for right ventricular function, with the results favouring the use of SPECT-35%. The results are better than those of equilibrium planar radionuclide angiography, but poorer than those previously reported for the left ventricle with SPECT radionuclide angiography. They need to be confirmed in a larger population.

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

Massie, B.; Kramer, B.L.; Topic, N.

Although the resting hemodynamic effects of captopril in congestive heart failure are known, little information is available about the hemodynamic response to captopril during exercise or about changes in noninvasive measurements of the size and function of both ventricles. In this study, 14 stable New York Heart Association class III patients were given 25 mg of oral captopril. Rest and exercise hemodynamic measurements and blood pool scintigrams were performed simultaneously before and 90 minutes after captopril. The radionuclide studies were analyzed for left and right ventricular end-diastolic volumes, end-systolic volumes, ejection fractions and pulmonary blood volume. The primary beneficial responsesmore » at rest were decreases in left and right ventricular end-diastolic volumes from 388 + 81 to 350 + 77 ml (p < 0.01) and from 52 + 26 to 43 + 20 volume units (p < 0.01), respectively, and in their corresponding filling pressures, from 24 + 10 to 17 + 9 mm Hg and 10 + 5 to and + 5 mm Hg (both p < 0.01). Altough stroke volume did not increase significantly, both left and right ventricular ejection fractions increased slightly, from 19 + 6% to 22 + 5% and from 25 + 9% to 29 + 11%, respectively (both p < 0.01). During exercise, similar changes were noted in both hemodynamic and radionuclide indexes. Thus, in patients with moderate symptomatic limitation from chronic heart failure, captopril predominantly reduces ventricular volume and filling pressure, with a less significant effect on cardiac output. These effects persist during exercise, when systemic vascular resistance is already very low. Radionuclide techniques are valuable in assessing the drug effect in these subjects, particularly when ventricular volumes are also measured.« less

Heart rate-left ventricular ejection time relations - Variations during postural change and cardiovascular challenges

NASA Technical Reports Server (NTRS)

Lance, V. Q.; Spodick, D. H.

1976-01-01

Experiments were conducted on healthy human subjects to determine HR-LVET (Heart Rate-Left Ventricular Ejection Time) regression relations in different postures, including tilt, and during isometric exercise. The subjects were tested in the resting state in supine and sitting positions, during isometric handgrip in supine and sitting positions and during 70 deg headup tilt. The recordings included a bipolar electrocardiogram and a right external carotid pulse curve. Comparison of the HR-LVET relation for the conditions under analysis revealed differences among the respective regression equations, which can be explained by the well-established differences in stroke volume and ejection rate among these states. These differences appear to account for the fact that under conditions in which stroke volume variations should be the major determinant, slopes will be similar but intercepts will vary. Since substantial differences among intercepts are observed, caution should be exercised whenever the intercept factor is used to predict LVET for HR.

Cardiac structure and function in the obese: a cardiovascular magnetic resonance imaging study.

PubMed

Danias, Peter G; Tritos, Nicholas A; Stuber, Matthias; Kissinger, Kraig V; Salton, Carol J; Manning, Warren J

2003-07-01

Obesity is a major health problem in the Western world. Among obese subjects cardiac pathology is common, but conventional noninvasive imaging modalities are often suboptimal for detailed evaluation of cardiac structure and function. We investigated whether cardiovascular magnetic resonance imaging (CMR) can better characterize possible cardiac abnormalities associated with obesity, in the absence of other confounding comorbidities. In this prospective cross-sectional study, CMR was used to quantify left and right ventricular volumes, ejection fraction, mass, cardiac output, and apical left ventricular rotation in 25 clinically healthy obese men and 25 age-matched lean controls. Obese subjects had higher left ventricular mass (203 +/- 38 g vs. 163 +/- 22 g, p < 0.001), end-diastolic volume (176 +/- 29 mL vs. 156 +/- 25 mL, p < 0.05), and cardiac output (8.2 +/- 1.2 L/min vs. 6.4 +/- 1.3 L/min, p < 0.001). The obese also had increased right ventricular mass (105 +/- 25 g vs. 87 +/- 18 g, p < 0.005) and end-diastolic volume (179 +/- 36 mL vs. 155 +/- 28 mL, p < 0.05). When indexed for height, differences in left and right ventricular mass, and left ventricular end-diastolic volume remained significant. Apical left ventricular rotation and rotational velocity patterns were also different between obese and lean subjects. Obesity is independently associated with remodeling of the heart. Cardiovascular magnetic resonance imaging identifies subtle cardiac abnormalities and may be the preferred imaging technique to evaluate cardiac structure and function in the obese.

Use of Cardiac Computed Tomography for Ventricular Volumetry in Late Postoperative Patients with Tetralogy of Fallot.

PubMed

Kim, Ho Jin; Mun, Da Na; Goo, Hyun Woo; Yun, Tae-Jin

2017-04-01

Cardiac computed tomography (CT) has emerged as an alternative to magnetic resonance imaging (MRI) for ventricular volumetry. However, the clinical use of cardiac CT requires external validation. Both cardiac CT and MRI were performed prior to pulmonary valve implantation (PVI) in 11 patients (median age, 19 years) who had undergone total correction of tetralogy of Fallot during infancy. The simplified contouring method (MRI) and semiautomatic 3-dimensional region-growing method (CT) were used to measure ventricular volumes. All volumetric indices measured by CT and MRI generally correlated well with each other, except for the left ventricular end-systolic volume index (LV-ESVI), which showed the following correlations with the other indices: the right ventricular end-diastolic volume index (RV-EDVI) (r=0.88, p<0.001), the right ventricular end-systolic volume index (RV-ESVI) (r=0.84, p=0.001), the left ventricular end-diastolic volume index (LV-EDVI) (r=0.90, p=0.001), and the LV-ESVI (r=0.55, p=0.079). While the EDVIs measured by CT were significantly larger than those measured by MRI (median RV-EDVI: 197 mL/m 2 vs. 175 mL/m 2 , p=0.008; median LV-EDVI: 94 mL/m 2 vs. 92 mL/m 2 , p=0.026), no significant differences were found for the RV-ESVI or LV-ESVI. The EDVIs measured by cardiac CT were greater than those measured by MRI, whereas the ESVIs measured by CT and MRI were comparable. The volumetric characteristics of these 2 diagnostic modalities should be taken into account when indications for late PVI after tetralogy of Fallot repair are assessed.

Allometric scaling of echocardiographic measurements in healthy Spanish foals with different body weight.

PubMed

Rovira, S; Muñoz, A; Rodilla, V

2009-04-01

Scaling in biology is usually allometric, and therefore, the size of the heart may be expressed as a power function of body weight (BW). The present research analyses the echocardiographic measurements in 68 healthy Spanish foals weighed between 70 and 347kg in order to determine the correct scaling exponent for the allometric equation. The echocardiographic parameters measured were: left ventricular internal dimensions (LVID), free wall thickness (LVFWT), interventricular septum thickness (IVST) at systole (s) and diastole (d), EPSS (distance between the point E of the mitral valve and the interventricular septum), and aorta diameters at the level of the aortic valve (AOD), base of valve leaflets (ABS), sinus of Valsalva (ASV) and sino-tubular junction (AJT). Indices of left ventricular performance were calculated. It was found that LVIDd, IVSTs, AOD, and ASV have a relationship to BW raised to 0.300-0.368 power, whereas left ventricular end-diastolic volume and stroke volume scaled to BW raised to 0.731-0.712 power. With these data, appropriate values can be calculated for normal Spanish foals.

Investigating the Role of Interventricular Interdependence in Development of Right Heart Dysfunction During LVAD Support: A Patient-Specific Methods-Based Approach.

PubMed

Sack, Kevin L; Dabiri, Yaghoub; Franz, Thomas; Solomon, Scott D; Burkhoff, Daniel; Guccione, Julius M

2018-01-01

Predictive computation models offer the potential to uncover the mechanisms of treatments whose actions cannot be easily determined by experimental or imaging techniques. This is particularly relevant for investigating left ventricular mechanical assistance, a therapy for end-stage heart failure, which is increasingly used as more than just a bridge-to-transplant therapy. The high incidence of right ventricular failure following left ventricular assistance reflects an undesired consequence of treatment, which has been hypothesized to be related to the mechanical interdependence between the two ventricles. To investigate the implication of this interdependence specifically in the setting of left ventricular assistance device (LVAD) support, we introduce a patient-specific finite-element model of dilated chronic heart failure. The model geometry and material parameters were calibrated using patient-specific clinical data, producing a mechanical surrogate of the failing in vivo heart that models its dynamic strain and stress throughout the cardiac cycle. The model of the heart was coupled to lumped-parameter circulatory systems to simulate realistic ventricular loading conditions. Finally, the impact of ventricular assistance was investigated by incorporating a pump with pressure-flow characteristics of an LVAD (HeartMate II™ operating between 8 and 12 k RPM) in parallel to the left ventricle. This allowed us to investigate the mechanical impact of acute left ventricular assistance at multiple operating-speeds on right ventricular mechanics and septal wall motion. Our findings show that left ventricular assistance reduces myofiber stress in the left ventricle and, to a lesser extent, right ventricle free wall, while increasing leftward septal-shift with increased operating-speeds. These effects were achieved with secondary, potentially negative effects on the interventricular septum which showed that support from LVADs, introduces unnatural bending of the septum and with it, increased localized stress regions. Left ventricular assistance unloads the left ventricle significantly and shifts the right ventricular pressure-volume-loop toward larger volumes and higher pressures; a consequence of left-to-right ventricular interactions and a leftward septal shift. The methods and results described in the present study are a meaningful advancement of computational efforts to investigate heart-failure therapies in silico and illustrate the potential of computational models to aid understanding of complex mechanical and hemodynamic effects of new therapies.

Right ventricle functional parameters estimation in arrhythmogenic right ventricular dysplasia using a robust shape based deformable model.

PubMed

Oghli, Mostafa Ghelich; Dehlaghi, Vahab; Zadeh, Ali Mohammad; Fallahi, Alireza; Pooyan, Mohammad

2014-07-01

Assessment of cardiac right-ventricle functions plays an essential role in diagnosis of arrhythmogenic right ventricular dysplasia (ARVD). Among clinical tests, cardiac magnetic resonance imaging (MRI) is now becoming the most valid imaging technique to diagnose ARVD. Fatty infiltration of the right ventricular free wall can be visible on cardiac MRI. Finding right-ventricle functional parameters from cardiac MRI images contains segmentation of right-ventricle in each slice of end diastole and end systole phases of cardiac cycle and calculation of end diastolic and end systolic volume and furthermore other functional parameters. The main problem of this task is the segmentation part. We used a robust method based on deformable model that uses shape information for segmentation of right-ventricle in short axis MRI images. After segmentation of right-ventricle from base to apex in end diastole and end systole phases of cardiac cycle, volume of right-ventricle in these phases calculated and then, ejection fraction calculated. We performed a quantitative evaluation of clinical cardiac parameters derived from the automatic segmentation by comparison against a manual delineation of the ventricles. The manually and automatically determined quantitative clinical parameters were statistically compared by means of linear regression. This fits a line to the data such that the root-mean-square error (RMSE) of the residuals is minimized. The results show low RMSE for Right Ventricle Ejection Fraction and Volume (≤ 0.06 for RV EF, and ≤ 10 mL for RV volume). Evaluation of segmentation results is also done by means of four statistical measures including sensitivity, specificity, similarity index and Jaccard index. The average value of similarity index is 86.87%. The Jaccard index mean value is 83.85% which shows a good accuracy of segmentation. The average of sensitivity is 93.9% and mean value of the specificity is 89.45%. These results show the reliability of proposed method in these cases that manual segmentation is inapplicable. Huge shape variety of right-ventricle led us to use a shape prior based method and this work can develop by four-dimensional processing for determining the first ventricular slices.

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.

The usefulness of left atrial volume index and left ventricular mass index in determining subclinical cardiac involvement in patients with early-stage sarcoidosis.

PubMed

Kasapkara, H A; Şentürk, A; Bilen, E; Duran Karaduman, B; Ayhan, H; Özen, M B; Durmaz, T; Keleş, T; Bozkurt, E

2016-08-01

Sarcoidosis is a multi-systemic granulomatous disease of unknown etiology. The present study has been designed to evaluate the importance of diastolic dysfunction with left atrial volume index (LAVi) and left ventricular mass index (LVMi) in determining subclinical cardiac involvement in subjects with stage I-II pulmonary sarcoidosis. A total of 54 patients under follow-up for sarcoidosis without cardiac involvement and 56 healthy subjects were included in the study. The echocardiographic assessment of the patients revealed no significant difference between the two groups regarding left ventricular end-systolic and end-diastolic diameters, ejection fraction (LVEF) and annular velocity determined by tissue Doppler evaluation. The LVEF calculated was 61.8 ± 7.8 % in the sarcoidosis group versus 64.1 ± 2.7 % in the control group (p = 0.04). Left ventricular interventricular septum thickness, posterior wall thickness, and relative wall thickness were significantly higher in the sarcoidosis group compared to the control group (p < 0.001). The sarcoidosis group had higher LVM and LVMi values compared to the control group (145 ± 18.1 and 79 ± 14 g/m(2), 135 ± 27.7 and 74 ± 14.2 g/m(2); p = 0.020 and p = 0.021, respectively). Left atrial end-systolic volume and LAVi were higher in the sarcoidosis group (28.7 ± 18.5; 15.6 ± 10.2) compared to the control group (16.6 ± 10.9; 8.9 ± 5.5) with a statistically significant difference (p < 0.001). The present study indicates diastolic dysfunction and increased LVMi despite normal systolic function in patients with early-stage sarcoidosis without cardiac involvement. Also, the diastolic parameters were normal without showing any significant difference compared to the control group while there was a statistically significant increase in LAVi. This finding suggests that LAVi may be the earliest marker of diastolic dysfunction in patients with early-stage sarcoidosis without cardiac involvement.

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.

Effects of upright and supine position on cardiac rest and exercise response in aortic regurgitation.

PubMed

Shen, W F; Roubin, G S; Fletcher, P J; Choong, C Y; Hutton, B F; Harris, P J; Kelly, D T

1985-02-01

The effects of upright and supine position on cardiac response to exercise were assessed by radionuclide ventriculography in 15 patients with moderate to severe aortic regurgitation (AR) and in 10 control subjects. In patients with AR, heart rate was higher during upright exercise, but systolic and diastolic blood pressure and left ventricular (LV) output were similar during both forms of exercise. LV stroke volume and end-diastolic volume were not altered during supine exercise. LV end-systolic volume increased and ejection fraction decreased during supine exercise, but both were unchanged during upright exercise. Of 15 patients, 5 in the upright and 12 in the supine position had an abnormal LV ejection fraction response to exercise (p less than 0.01). Right ventricular ejection fraction increased and regurgitant index decreased with both forms of exercise and was not significantly different between the 2 positions. Thus, posture is important in determining LV response to exercise in patients with moderate to severe AR.

A modified Glenn shunt reduces venous congestion during acute right ventricular failure due to pulmonary banding: a randomized experimental study

PubMed Central

Vikholm, Per; Schiller, Petter; Hellgren, Laila

2014-01-01

OBJECTIVES Right ventricular failure after left ventricular assist device implantation is a serious complication with high rates of mortality and morbidity. It has been demonstrated in experimental settings that volume exclusion of the right ventricle with a modified Glenn shunt can improve haemodynamics during ischaemic right ventricular failure. However, the concept of a modified Glenn shunt is dependent on a normal pulmonary vascular resistance, which can limit its use in some patients. The aim of this study was to explore the effects of volume exclusion with a modified Glenn shunt during right ventricular failure due to pulmonary banding, and to study the alterations in genetic expression in the right ventricle due to pressure and volume overload. METHODS Experimental right ventricular failure was induced in pigs (n = 11) through 2 h of pulmonary banding. The pigs were randomized to either treatment with a modified Glenn shunt and pulmonary banding (n = 6) or solely pulmonary banding (n = 5) as a control group. Haemodynamic measurements, blood samples and right ventricular biopsies for genetic analysis were sampled at baseline, at right ventricular failure (i.e. 2 h of pulmonary banding) and 1 h post-right ventricular failure in both groups. RESULTS Right atrial pressure increased from 10 mmHg (9.0–12) to 18 mmHg (16–22) (P < 0.01) and the right ventricular pressure from 31 mmHg (26–35) to 57 mmHg (49–61) (P < 0.01) after pulmonary banding. Subsequent treatment with the modified Glenn shunt resulted in a decrease in right atrial pressure to 13 mmHg (11–14) (P = 0.03). In the control group, right atrial pressure was unchanged at 19 mmHg (16–20) (P = 0.18). At right heart failure, there was an up-regulation of genes associated with heart failure, inflammation, angiogenesis, negative regulation of cell death and proliferation. CONCLUSIONS Volume exclusion with a modified Glenn shunt during right ventricular failure reduced venous congestion compared with the control group. The state of right heart failure was verified through genetic expressional changes. PMID:24396048

Early results of MitraClip system implantation by real-time three-dimensional speckle-tracking left ventricle analysis.

PubMed

Scandura, Salvatore; Dipasqua, Fabio; Gargiulo, Giuseppe; Capodanno, Davide; Caggegi, Anna; Grasso, Carmelo; Mangiafico, Sarah; Pistritto, Anna Maria; Immè, Sebastiano; Chiarandà, Marta; Ministeri, Margherita; Ronsivalle, Giuseppe; Cannata, Stefano; Arcidiacono, Antonio Andrea; Capranzano, Piera; Tamburino, Corrado

2016-11-01

To appraise the early effect of percutaneous mitral valve repair with the MitraClip system on myocardial function using real-time three-dimensional speckle-tracking echocardiography (3D-STE). Consecutive patients with moderate-to-severe or severe mitral regurgitation, undergoing mitral valve repair with the MitraClip system, were prospectively evaluated during the peri-procedural workout and follow-up. Left ventricular deformation was evaluated by a two-dimensional and 3D speckle-tracking analysis. 3D-STE acquisitions were elaborated obtaining real-time 3D global longitudinal strain evaluation, and by appraising both volumetric and hemodynamic parameters (i.e. left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction, cardiac output, and stroke volume). In all, 30 patients were included. At 1-month follow-up, 3D-STE analysis revealed no changes in left ventricular end-diastolic volume (162.6 ± 73.7 ml at baseline vs. 159.8 ± 64.5 ml at 1-month follow-up; P = 0.63) and a downward trend in left ventricular end-systolic volume (104.7 ± 52.0 vs. 100.1 ± 50.4 ml, respectively; P = 0.06). Left ventricular ejection fraction did not significantly increase (38.1 ± 11.3% at baseline vs. 39.4 ± 11.0% at 1-month follow-up; P = 0.20). No significant changes were reported in cardiac output (4.3 ± 2.0 l/min at baseline vs. 4.0 ± 1.5 l/min at follow-up; P = 0.377) and in stroke volume (59.5 ± 25.5 ml at baseline vs. 59.9 ± 20.7 ml at follow-up; P = 0.867). On the contrary, left ventricular deformation capability significantly improved, with the real-time 3D global longitudinal strain value changing from -9.8 ± 4.1% at baseline to -11.0 ± 4.4% at follow-up (P = 0.018). Accurately assessing myocardial function by the use of 3D-STE, this study reported irrelevant early changes in left ventricular size, but a positive effect on left ventricular deformation capability following mitral valve repair with the MitraClip system. These preliminary results need to be confirmed in larger series and extended to long-term follow-up.

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.

Effect of Sleep Apnea and Continuous Positive Airway Pressure on Cardiac Structure and Recurrence of Atrial Fibrillation

PubMed Central

Neilan, Tomas G.; Farhad, Hoshang; Dodson, John A.; Shah, Ravi V.; Abbasi, Siddique A.; Bakker, Jessie P.; Michaud, Gregory F.; van der Geest, Rob; Blankstein, Ron; Steigner, Michael; John, Roy M.; Jerosch‐Herold, Michael; Malhotra, Atul; Kwong, Raymond Y.

2013-01-01

Background Sleep apnea (SA) is associated with an increased risk of atrial fibrillation (AF). We sought to determine the effect of SA on cardiac structure in patients with AF, whether therapy for SA was associated with beneficial cardiac structural remodelling, and whether beneficial cardiac structural remodelling translated into a reduced risk of recurrence of AF after pulmonary venous isolation (PVI). Methods and Results A consecutive group of 720 patients underwent a cardiac magnetic resonance study before PVI. Patients with SA (n=142, 20%) were more likely to be male, diabetic, and hypertensive and have an increased pulmonary artery pressure, right ventricular volume, atrial dimensions, and left ventricular mass. Treated SA was defined as duration of continuous positive airway pressure therapy of >4 hours per night. Treated SA patients (n=71, 50%) were more likely to have paroxysmal AF, a lower blood pressure, lower ventricular mass, and smaller left atrium. During a follow‐up of 42 months, AF recurred in 245 patients. The cumulative incidence of AF recurrence was 51% in patients with SA, 30% in patients without SA, 68% in patients with untreated SA, and 35% in patients with treated SA. In a multivariable model, the presence of SA (hazard ratio 2.79, CI 1.97 to 3.94, P<0.0001) and untreated SA (hazard ratio 1.61, CI 1.35 to 1.92, P<0.0001) were highly associated with AF recurrence. Conclusions Patients with SA have an increased blood pressure, pulmonary artery pressure, right ventricular volume, left atrial size, and left ventricular mass. Therapy with continuous positive airway pressure is associated with lower blood pressure, atrial size, and ventricular mass, and a lower risk of AF recurrence after PVI. PMID:24275628

Atorvastatin Improves Ventricular Remodeling after Myocardial Infarction by Interfering with Collagen Metabolism

PubMed Central

Reichert, Karla; Pereira do Carmo, Helison Rafael; Galluce Torina, Anali; Diógenes de Carvalho, Daniela; Carvalho Sposito, Andrei; de Souza Vilarinho, Karlos Alexandre; da Mota Silveira-Filho, Lindemberg; Martins de Oliveira, Pedro Paulo

2016-01-01

Purpose Therapeutic strategies that modulate ventricular remodeling can be useful after acute myocardial infarction (MI). In particular, statins may exert effects on molecular pathways involved in collagen metabolism. The aim of this study was to determine whether treatment with atorvastatin for 4 weeks would lead to changes in collagen metabolism and ventricular remodeling in a rat model of MI. Methods Male Wistar rats were used in this study. MI was induced in rats by ligation of the left anterior descending coronary artery (LAD). Animals were randomized into three groups, according to treatment: sham surgery without LAD ligation (sham group, n = 14), LAD ligation followed by 10mg atorvastatin/kg/day for 4 weeks (atorvastatin group, n = 24), or LAD ligation followed by saline solution for 4 weeks (control group, n = 27). After 4 weeks, hemodynamic characteristics were obtained by a pressure-volume catheter. Hearts were removed, and the left ventricles were subjected to histologic analysis of the extents of fibrosis and collagen deposition, as well as the myocyte cross-sectional area. Expression levels of mediators involved in collagen metabolism and inflammation were also assessed. Results End-diastolic volume, fibrotic content, and myocyte cross-sectional area were significantly reduced in the atorvastatin compared to the control group. Atorvastatin modulated expression levels of proteins related to collagen metabolism, including MMP1, TIMP1, COL I, PCPE, and SPARC, in remote infarct regions. Atorvastatin had anti-inflammatory effects, as indicated by lower expression levels of TLR4, IL-1, and NF-kB p50. Conclusion Treatment with atorvastatin for 4 weeks was able to attenuate ventricular dysfunction, fibrosis, and left ventricular hypertrophy after MI in rats, perhaps in part through effects on collagen metabolism and inflammation. Atorvastatin may be useful for limiting ventricular remodeling after myocardial ischemic events. PMID:27880844

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.

Flecainide-induced proarrhythmia is attributed to abnormal changes in repolarization and refractoriness in perfused guinea-pig heart.

PubMed

Osadchii, Oleg E

2012-11-01

Flecainide is nonselective Na(+) channel blocker which may also inhibit I(Kr), the rapid component of the delayed rectifier. This study was designed to explore if proarrhythmic responses to flecainide noted in cardiac patients may be partly attributed to abnormal changes in repolarization and refractoriness. Monophasic action potential duration (APD) and effective refractory periods (ERP) were assessed at distinct epicardial and endocardial sites along with volume-conducted ECG recordings in isolated perfused guinea-pig heart preparations. Flecainide was found to prolong ventricular repolarization, with effect being greater at the left ventricular compared with the right ventricular epicardium. This change translated to reversal of the normal right ventricular-to-left ventricular transepicardial APD difference determined before drug infusion. An inverse correlation between local epicardial APD and corresponding activation time values seen at baseline was eliminated in flecainide-treated hearts, indicating the activation-to-repolarization uncoupling. Over transmural plane, flecainide produced a greater ERP lengthening at endocardium than epicardium, thus markedly increasing ERP dispersion across ventricular wall. Spontaneous short-lasting episodes of monomorphic ventricular tachycardia were observed in 45% of heart preparations upon flecainide infusion. In conclusion, in nonischemic guinea-pig heart, flecainide-induced proarrhythmia may be partly attributed to abnormal spatial gradients in repolarization and refractoriness and impaired transepicardial activation-to-repolarization coupling.

Myocardial scar location as detected by cardiac magnetic resonance is associated with the outcome in heart failure patients undergoing surgical ventricular reconstruction.

PubMed

Castelvecchio, Serenella; Careri, Giulia; Ambrogi, Federico; Camporeale, Antonia; Menicanti, Lorenzo; Secchi, Francesco; Lombardi, Massimo

2018-01-01

Post-infarction myocardial scar causes adverse left ventricular remodelling and negatively affects the prognosis. We sought to investigate whether scar extent and location obtained by cardiac magnetic resonance may affect the reverse remodelling and survival of heart failure patients undergoing surgical ventricular reconstruction. From January 2011 to December 2015, 151 consecutive patients with previous myocardial infarction and left ventricular remodelling underwent surgical ventricular reconstruction at our Institution, of which 88 (58%) patients had a preoperative protocol-standardized late gadolinium enhancement (LGE)-cardiac magnetic resonance examination during the week before surgery. We excluded 40 patients with devices (26%), 15 patients with irregular heart rhythm (permanent atrial fibrillation, 10% not included in the device group) or mixed contraindications (severe claustrophobia or presence of material magnetic resonance not compatible). Among the 145 survivors, 11 patients received an implantable cardioverter defibrillator after surgery (mostly for persistent low ejection fraction) and were excluded as well, yielding a total of 59 patients (48 men, aged 65 ± 9 years) who repeated a protocol-standardized LGE-cardiac magnetic resonance examination even 6 months postoperatively and therefore represent the study population. Patients were grouped according to the presence of LGE in the antero-basal left ventricular segments (Group A) or the absence of LGE in the same segments (Group B). The postoperative left ventricular end-systolic volume index was considered the primary end-point. After surgery, left ventricular end-systolic volume index and end-diastolic volume index significantly decreased (P < 0.001, for both), while diastolic sphericity index and ejection fraction significantly increased (P = 0.015 and P < 0.001, respectively). The presence of LGE in the antero-basal left ventricular segments (10 patients, Group A) was the only independent predictor of outcome (P = 0.02) at multivariate analysis, being the postoperative left ventricular end-systolic volume index significantly higher compared to that of patients of Group B (49 patients) (78 ± 26 ml/m2 vs 55 ± 20 ml/m2, P = 0.003). Furthermore, patients with a postoperative left ventricular end-systolic volume index >60 ml/m2 showed a higher risk of cardiac events (hazard ratio = 3.67, P = 0.02). In patients undergoing surgical ventricular reconstruction, LGE scar location affects the left ventricular reverse remodelling, which in turn might limit the survival benefit. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Cardiac Remodeling in Response to 1 Year of Intensive Endurance Training

PubMed Central

Arbab-Zadeh, Armin; Perhonen, Merja; Howden, Erin; Peshock, Ronald M.; Zhang, Rong; Adams-Huet, Beverly; Haykowsky, Mark J.; Levine, Benjamin D.

2017-01-01

Background It is unclear whether, and to what extent, the striking cardiac morphological manifestations of endurance athletes are a result of exercise training or a genetically determined characteristic of talented athletes. We hypothesized that prolonged and intensive endurance training in previously sedentary healthy young individuals could induce cardiac remodeling similar to that observed cross-sectionally in elite endurance athletes. Methods and Results Twelve previously sedentary subjects (aged 29±6 years; 7 men and 5 women) trained progressively and intensively for 12 months such that they could compete in a marathon. Magnetic resonance images for assessment of right and left ventricular mass and volumes were obtained at baseline and after 3, 6, 9, and 12 months of training. Maximum oxygen uptake (V̇o2 max) and cardiac output at rest and during exercise (C2H2 rebreathing) were measured at the same time periods. Pulmonary artery catheterization was performed before and after 1 year of training, and pressure-volume and Starling curves were constructed during decreases (lower body negative pressure) and increases (saline infusion) in cardiac volume. Mean V̇o2 max rose from 40.3±1.6 to 48.7±2.5 mL/kg per minute after 1 year (P<0.00001), associated with an increase in both maximal cardiac output and stroke volume. Left and right ventricular mass increased progressively with training duration and intensity and reached levels similar to those observed in elite endurance athletes. In contrast, left ventricular volume did not change significantly until 6 months of training, although right ventricular volume increased progressively from the outset; Starling and pressure-volume curves approached but did not match those of elite athletes. Conclusions One year of prolonged and intensive endurance training leads to cardiac morphological adaptations in previously sedentary young subjects similar to those observed in elite endurance athletes; however, it is not sufficient to achieve similar levels of cardiac compliance and performance. Contrary to conventional thinking, the left ventricle responds to exercise with initial concentric but not eccentric remodeling during the first 6 to 9 months after commencement of endurance training depending on the duration and intensity of exercise. Thereafter, the left ventricle dilates and restores the baseline mass-to-volume ratio. In contrast, the right ventricle responds to endurance training with eccentric remodeling at all levels of training. PMID:25281664

Relationship between right and left ventricular function in candidates for implantable cardioverter defibrillator with low left ventricular ejection fraction.

PubMed

Jimenez-Juan, Laura; Karur, Gauri R; Connelly, Kim A; Deva, Djeven; Yan, Raymond T; Wald, Rachel M; Singh, Sheldon; Leung, General; Oikonomou, Anastasia; Dorian, Paul; Angaran, Paul; Yan, Andrew T

2017-04-01

Indications for the primary prevention of sudden death using an implantable cardioverter defibrillator (ICD) are based predominantly on left ventricular ejection fraction (LVEF). However, right ventricular ejection fraction (RVEF) is also a known prognostic factor in a variety of structural heart diseases that predispose to sudden cardiac death. We sought to investigate the relationship between right and left ventricular parameters (function and volume) measured by cardiovascular magnetic resonance (CMR) among a broad spectrum of patients considered for an ICD. In this retrospective, single tertiary-care center study, consecutive patients considered for ICD implantation who were referred for LVEF assessment by CMR were included. Right and left ventricular function and volumes were measured. In total, 102 patients (age 62±14 years; 23% women) had a mean LVEF of 28±11% and RVEF of 44±12%. The left ventricular and right ventricular end diastolic volume index was 140±42 mL/m 2 and 81±27 mL/m 2 , respectively. Eighty-six (84%) patients had a LVEF <35%, and 63 (62%) patients had right ventricular systolic dysfunction. Although there was a significant and moderate correlation between LVEF and RVEF ( r =0.40, p <0.001), 32 of 86 patients (37%) with LVEF <35% had preserved RVEF, while 9 of 16 patients (56%) with LVEF ≥35% had right ventricular systolic dysfunction (Kappa=0.041). Among patients being considered for an ICD, there is a positive but moderate correlation between LVEF and RVEF. A considerable proportion of patients who qualify for an ICD based on low LVEF have preserved RVEF, and vice versa.

Ductal stenting retrains the left ventricle in transposition of great arteries with intact ventricular septum.

PubMed

Sivakumar, Kothandam; Francis, Edwin; Krishnan, Prasad; Shahani, Jagdish

2006-11-01

In late presenters with transposition of the great arteries, intact ventricular septum, and regressing left ventricle, left ventricular retraining by pulmonary artery banding and aortopulmonary shunt is characterized by a stormy postoperative course and high costs. Ductal stenting in the cardiac catheterization laboratory is conceptualized to retrain the left ventricle with less morbidity. Recanalization and transcatheter stenting of patent ductus arteriosus was performed in patients with transposition to induce pressure and volume overload to the regressing left ventricle. Serial echocardiographic monitoring of left ventricular shape, mass, free wall thickness, and volumes was done, and once the left ventricle was adequately prepared, an arterial switch was performed. The ductal stent was removed and the remaining surgical steps were similar to a 1-stage arterial switch operation. Postoperative course, need for inotropic agents, and left ventricular function were monitored. Ductal stenting in 2 patients aged 3 months resulted in improvement of indexed left ventricular mass from 18.9 to 108.5 g/m2, left ventricular free wall thickness from 2.5 to 4.8 mm, and indexed left ventricular volumes from 7.6 to 29.5 mL/m2 within 3 weeks. Both patients underwent arterial switch (bypass times 125 and 158 minutes) uneventfully, needed inotropic agents and ventilatory support for 3 days, and were discharged in 8 and 10 days. Ductal stenting is a less morbid method of left ventricular retraining in transposition of the great arteries with regressed left ventricle. Its major advantages lie in avoiding pulmonary artery distortion and neoaortic valve regurgitation resulting from banding and also in avoiding thoracotomy.

Change of heart dimensions and function during pregnancy in goats.

PubMed

Szaluś-Jordanow, Olga; Czopowicz, Michał; Witkowski, Lucjan; Moroz, Agata; Mickiewicz, Marcin; Frymus, Tadeusz; Markowska-Daniel, Iwona; Bagnicka, Emilia; Kaba, Jarosław

2018-03-08

The study aimed to evaluate the effect of pregnancy on heart diameters and function in goats. Transthoracic echocardiography of 12 female dairy goats of two Polish regional breeds was performed. A Mindray M7 diagnostic ultrasound system with Phased Array transducer was used. Simultaneously, electrocardiography was recorded. All animals were examined four times - at mating season, at the end of the first trimester, at the end of the second trimester and just before kidding. Eleven measurements were taken each time: aortic and left atrial diameter (AoD and LAD), right and left ventricular internal diameter in diastole (RVIDd and LVIDd), left ventricular internal diameter in systole (LVIDs), inter-ventricular septum thickness in diastole and systole (IVSd and IVSd) and left ventricular posterior wall in diastole and systole (LVPWd and LVPWs), maximum left and right ventricular outflow tract velocity (RVOT Vmax and LVOT Vmax). Nine consecutive measurements were derived: the ratio of the left atrial diameter to the aortic diameter (AoD/LAD), left ventricular fractional shortening (FS%), left ventricular ejection fraction (EF%), maximum outflow tract pressure gradients (RVOT PGmax and LVOT PGmax), left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV), stroke volume (SV) and cardiac output (CO). HR, LAD, LVPWs, IVSs increased significantly in the first trimester. AoD and RVIDd were significantly higher around parturition. LVIDd, FS%, EF%, SV and CO rose both in the first and third trimester. No measurement decreased during pregnancy. The study confirms that pregnancy causes changes in the heart size and functioning. Copyright © 2018. Published by Elsevier Ltd.

Volumetric measurements in patients with corrected tetralogy of Fallot: comparison of short-axis versus axial cardiac MRI and echocardiography.

PubMed

Schelhorn, Juliane; Neudorf, Ulrich; Schemuth, Haemi; Nensa, Felix; Nassenstein, Kai; Schlosser, Thomas W

2015-11-01

Patients with corrected tetralogy of Fallot (cToF) are prone to develop pulmonary regurgitation and right ventricular enlargement resulting in long-term complications, thus correct right ventricular volumetric monitoring is crucial. However, it remains controversial which cardiovascular magnetic resonance imaging (CMRI) slice orientation is most appropriate in cToF for the analysis of the right ventricular volume. To investigate which slice orientation is most suited for right ventricular volumetry in cToF we compared short-axis and axial slices, and furthermore we compared right ventricular data between CMRI and echocardiography. Thirty CMRI examinations of 27 patients with cToF were included retrospectively. Right ventricular end-diastolic (EDV) and end-systolic volume (ESV) were derived from short-axis and axial cine CMRI planes. Furthermore, pulmonary trunk forward flow in phase-contrast CMRI and right ventricular inner diastolic diameter in echocardiography (R VIDdiast) were measured. By Bland-Altman and variance analysis intra- and inter-observer agreement were assessed for cine CMRI data. By Pearson correlation CMRI cine and phase-contrast data and CMRI cine and echocardiographic data were compared. Intra- and inter-observer variability for right ventricular EDV were significantly lower in axial slices (P = 0.016, P = 0.010). For right ventricular ESV a trend towards a lower intra- and inter-observer variability in axial slices was found (P = 0.063, P = 0.138). Right ventricular stroke volume in short-axis (r = 0.872, P < 0.001) and in axial (r = 0.914, P < 0.001) planes correlated highly, respectively very highly with pulmonary trunk forward flow in phase-contrast CMRI. R VIDdiast correlated highly with right ventricular EDV assessed by short-axis and axial CMRI (P < 0.001, P < 0.001). Due to lower intra- and inter-observer variability, axial slices are recommended for right ventricular volumetry in cToF. © The Foundation Acta Radiologica 2014.

Alterations in left ventricular volumes induced by Valsalva manoeuvre

NASA Technical Reports Server (NTRS)

Brooker, J. Z.; Alderman, E. L.; Harrison, D. C.

1974-01-01

Five patients were studied with left ventriculography during different phases of the Valsalva manoeuvre. Small doses of contrast medium allowed adequate repetitive visualization of the left ventricle for volume calculation. During strain phase, the volume of the left ventricle decreased by nearly 50 per cent in each case, and stroke volume and cardiac output also dropped strikingly. Release of straining was attended by a sharp rebound of left ventricular volume to control levels, with a transient surge of increased cardiac output 42 per cent above that of the resting state.

Left ventricular geometric patterns in end-stage kidney disease: Determinants and course over time.

PubMed

Nubé, Menso J; Hoekstra, Tiny; Doganer, Volkan; Bots, Michiel L; Blankestijn, Peter J; van den Dorpel, Marinus; Kamp, Otto; Ter Wee, Piet M; de Roij van Zuijdewijn, Camiel L M; Grooteman, Muriel P C

2018-02-20

While concentric left ventricular hypertrophy (cLVH) predominates in non-dialysis-dependent chronic kidney disease (CKD), eccentric left ventricular hypertrophy (eLVH) is most prevalent in dialysis-dependent CKD stage 5 (CKD5D). In these patients, the risk of sudden death is 5× higher than in individuals with cLVH. Currently, it is unknown which factors determine left ventricular (LV) geometry and how it changes over time in CKD5D. Data from participants of the CONvective TRAnsport Study who underwent serial transthoracic echocardiography were used. Based on left ventricular mass (LVM) and relative wall thickness (RWT), 4 types of left ventricular geometry were distinguished: normal, concentric remodeling, eLVH, and cLVH. Determinants of eLVH were assessed with logistic regression. Left ventricular geometry of patients who died and survived were compared. Long-term changes in RWT and LVM were evaluated with a linear mixed model. Three hundred twenty-two patients (63.1 ± 13.3 years) were included. At baseline, LVH was present in 71% (cLVH: 27%; eLVH: 44%). Prior cardiovascular disease (CVD) was positively associated with eLVH and ß-blocker use inversely. None of the putative volume parameters showed any relationship with eLVH. Although eLVH was most prevalent in non-survivors, the distribution of left ventricular geometry did not vary over time. The finding that previous CVD was positively associated with eLVH may result from the permanent high cardiac output and the strong tendency for aortic valve calcification in this group of long-term hemodialysis patients, who suffer generally also from chronic anemia and various other metabolic derangements. No association was found between eLVH and parameters of fluid balance. The distribution of left ventricular geometry did not alter over time. The assumption that LV geometry worsens over time in susceptible individuals, who then suffer from a high risk of dying, may explain these findings. © 2018 The Authors Hemodialysis International published by Wiley Periodicals, Inc. on behalf of International Society for Hemodialysis.

Evaluation of Right Ventricular Myocardial Mechanics Using Velocity Vector Imaging of Cardiac MRI Cine Images in Transposition of the Great Arteries Following Atrial and Arterial Switch Operations.

PubMed

Thattaliyath, Bijoy D; Forsha, Daniel E; Stewart, Chad; Barker, Piers C A; Campbell, Michael J

2015-01-01

The aim of the study was to determine right and left ventricle deformation parameters in patients with transposition of the great arteries who had undergone atrial or arterial switch procedures. Patients with transposition are born with a systemic right ventricle. Historically, the atrial switch operation, in which the right ventricle remains the systemic ventricle, was performed. These patients have increased rates of morbidity and mortality. We used cardiac MRI with Velocity Vector Imaging analysis to characterize and compare ventricular myocardial deformation in patients who had an atrial switch or arterial switch operation. Patients with a history of these procedures, who had a clinically ordered cardiac MRI were included in the study. Consecutive 20 patients (75% male, 28.7 ± 1.8 years) who underwent atrial switch operation and 20 patients (60% male, 17.7 ± 1.9 years) who underwent arterial switch operation were included in the study. Four chamber and short-axis cine images were used to determine longitudinal and circumferential strain and strain rate using Vector Velocity Imaging software. Compared with the arterial switch group, the atrial switch group had decreased right ventricular ejection fraction and increased end-diastolic and end-systolic volumes, and no difference in left ventricular ejection fraction and volumes. The atrial switch group had decreased longitudinal and circumferential strain and strain rate. When compared with normal controls multiple strain parameters in the atrial switch group were reduced. Myocardial deformation analysis of transposition patients reveals a reduction of right ventricular function and decreased longitudinal and circumferential strain parameters in patients with an atrial switch operation compared with those with arterial switch operation. A better understanding of the mechanisms of right ventricle failure in transposition of great arteries may lead to improved therapies and adaptation. © 2015 Wiley Periodicals, Inc.

Three-dimensional visual guidance improves the accuracy of calculating right ventricular volume with two-dimensional echocardiography

NASA Technical Reports Server (NTRS)

Dorosz, Jennifer L.; Bolson, Edward L.; Waiss, Mary S.; Sheehan, Florence H.

2003-01-01

Three-dimensional guidance programs have been shown to increase the reproducibility of 2-dimensional (2D) left ventricular volume calculations, but these systems have not been tested in 2D measurements of the right ventricle. Using magnetic fields to identify the probe location, we developed a new 3-dimensional guidance system that displays the line of intersection, the plane of intersection, and the numeric angle of intersection between the current image plane and previously saved scout views. When used by both an experienced and an inexperienced sonographer, this guidance system increases the accuracy of the 2D right ventricular volume measurements using a monoplane pyramidal model. Furthermore, a reconstruction of the right ventricle, with a computed volume similar to the calculated 2D volume, can be displayed quickly by tracing a few anatomic structures on 2D scans.

Pressure-volume Relationship in the Stress-echocardiography Laboratory: Does (Left Ventricular End-diastolic) Size Matter?

PubMed

Bombardini, Tonino; Mulieri, Louis A; Salvadori, Stefano; Costantino, Marco Fabio; Scali, Maria Chiara; Marzilli, Mario; Picano, Eugenio

2017-02-01

The variation between rest and peak stress end-systolic pressure-volume relation is an afterload-independent index of left ventricular contractility. Whether and to what extent it depends on end-diastolic volume remains unclear. The aim of this study was to assess the dependence of the delta rest-stress end-systolic pressure-volume relation on end-diastolic volume in patients with negative stress echo and all ranges of resting left ventricular function. We analyzed interpretable data obtained in 891 patients (593 men, age 63 ± 12 years) with ejection fraction 47% ± 12%: 338 were normal or near-normal or hypertensive; 229 patients had coronary artery disease; and 324 patients had ischemic or nonischemic dilated cardiomyopathy. They were studied with exercise (n = 172), dipyridamole (n = 482) or dobutamine (n = 237) stress echocardiography. The end-systolic pressure-volume relation was evaluated at rest and peak stress from raw measurement of systolic arterial pressure by cuff sphygmomanometer and end-systolic volume by biplane Simpson rule 2-dimensional echocardiography. Absolute values of delta rest-stress end-systolic pressure-volume relation were higher for exercise and dobutamine than for dipyridamole. In the overall population, an inverse relationship between end-systolic pressure-volume relation and end-diastolic volume was present at rest (r 2 = 0.69, P < .001) and peak stress (r 2 = 0.56, P < .001), but was absent if the delta rest-stress end-systolic pressure-volume relation was considered (r 2 = 0.13). Left ventricular end-diastolic volume does not affect the rest-stress changes in end-systolic pressure-volume relation in either normal or abnormal left ventricles during physical or pharmacological stress. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Intracranial cerebrospinal fluid spaces imaging using a pulse-triggered three-dimensional turbo spin echo MR sequence with variable flip-angle distribution.

PubMed

Hodel, Jérôme; Silvera, Jonathan; Bekaert, Olivier; Rahmouni, Alain; Bastuji-Garin, Sylvie; Vignaud, Alexandre; Petit, Eric; Durning, Bruno; Decq, Philippe

2011-02-01

To assess the three-dimensional turbo spin echo with variable flip-angle distribution magnetic resonance sequence (SPACE: Sampling Perfection with Application optimised Contrast using different flip-angle Evolution) for the imaging of intracranial cerebrospinal fluid (CSF) spaces. We prospectively investigated 18 healthy volunteers and 25 patients, 20 with communicating hydrocephalus (CH), five with non-communicating hydrocephalus (NCH), using the SPACE sequence at 1.5T. Volume rendering views of both intracranial and ventricular CSF were obtained for all patients and volunteers. The subarachnoid CSF distribution was qualitatively evaluated on volume rendering views using a four-point scale. The CSF volumes within total, ventricular and subarachnoid spaces were calculated as well as the ratio between ventricular and subarachnoid CSF volumes. Three different patterns of subarachnoid CSF distribution were observed. In healthy volunteers we found narrowed CSF spaces within the occipital aera. A diffuse narrowing of the subarachnoid CSF spaces was observed in patients with NCH whereas patients with CH exhibited narrowed CSF spaces within the high midline convexity. The ratios between ventricular and subarachnoid CSF volumes were significantly different among the volunteers, patients with CH and patients with NCH. The assessment of CSF spaces volume and distribution may help to characterise hydrocephalus.

Rat strain differences in brain structure and neurochemistry in response to binge alcohol.

PubMed

Zahr, Natalie M; Mayer, Dirk; Rohlfing, Torsten; Hsu, Oliver; Vinco, Shara; Orduna, Juan; Luong, Richard; Bell, Richard L; Sullivan, Edith V; Pfefferbaum, Adolf

2014-01-01

Ventricular enlargement is a robust phenotype of the chronically dependent alcoholic human brain, yet the mechanism of ventriculomegaly is unestablished. Heterogeneous stock Wistar rats administered binge EtOH (3 g/kg intragastrically every 8 h for 4 days to average blood alcohol levels (BALs) of 250 mg/dL) demonstrate profound but reversible ventricular enlargement and changes in brain metabolites (e.g., N-acetylaspartate (NAA) and choline-containing compounds (Cho)). Here, alcohol-preferring (P) and alcohol-nonpreferring (NP) rats systematically bred from heterogeneous stock Wistar rats for differential alcohol drinking behavior were compared with Wistar rats to determine whether genetic divergence and consequent morphological and neurochemical variation affect the brain's response to binge EtOH treatment. The three rat lines were dosed equivalently and approached similar BALs. Magnetic resonance imaging and spectroscopy evaluated the effects of binge EtOH on brain. As observed in Wistar rats, P and NP rats showed decreases in NAA. Neither P nor NP rats, however, responded to EtOH intoxication with ventricular expansion or increases in Cho levels as previously noted in Wistar rats. Increases in ventricular volume correlated with increases in Cho in Wistar rats. The latter finding suggests that ventricular volume expansion is related to adaptive changes in brain cell membranes in response to binge EtOH. That P and NP rats responded differently to EtOH argues for intrinsic differences in their brain cell membrane composition. Further, differential metabolite responses to EtOH administration by rat strain implicate selective genetic variation as underlying heterogeneous effects of chronic alcoholism in the human condition.

Cardiovascular studies using the chimpanzee (Pan troglodytes)

NASA Technical Reports Server (NTRS)

Hinds, J. E.; Cothran, L. N.; Hawthorne, E. W.

1977-01-01

Despite the phylogenetic similarities between chimpanzees and man, there exists a paucity of reliable data on normal cardiovascular function and the physiological responses of the system to standard interventions. Totally implanted biotelemetry systems or hardwire analog techniques were used to examine the maximum number of cardiovascular variables which could be simultaneously monitored without significantly altering the system's performance. This was performed in order to acquire base-line data not previously obtained in this species, to determine cardiovascular response to specific forcing functions such as ventricular pacing, drug infusions, and lower body negative pressure. A cardiovascular function profile protocol was developed in order to adjust independently the three major factors which modify ventricular performance, namely, left ventricular performance, left ventricular preload, afterload, and contractility. Cardiac pacing at three levels above the ambient rate was used to adjust end diastolic volume (preload). Three concentrations of angiotensin were infused continuously to evaluate afterload in a stepwide fashion. A continuous infusion of dobutamine was administered to raise the manifest contractile state of the heart.

Hemodynamic responses to external counterbalancing of auto-positive end-expiratory pressure in mechanically ventilated patients with chronic obstructive pulmonary disease.

PubMed

Baigorri, F; de Monte, A; Blanch, L; Fernández, R; Vallés, J; Mestre, J; Saura, P; Artigas, A

1994-11-01

To study the effect of positive end-expiratory pressure (PEEP) on right ventricular hemodynamics and ejection fraction in patients with chronic obstructive pulmonary disease and positive alveolar pressure throughout expiration by dynamic hyperinflation (auto-PEEP). Open, prospective, controlled trial. General intensive care unit of a community hospital. Ten patients sedated and paralyzed with an acute exacerbation of chronic obstructive pulmonary disease undergoing mechanical ventilation. Insertion of a pulmonary artery catheter modified with a rapid response thermistor and a radial arterial catheter. PEEP was then increased from 0 (PEEP 0) to auto-PEEP level (PEEP = auto-PEEP) and 5 cm H2O above that (PEEP = auto-PEEP +5). At each level of PEEP, airway pressures, flow and volume, hemodynamic variables (including right ventricular ejection fraction by thermodilution technique), and blood gas analyses were recorded. The mean auto-PEEP was 6.6 +/- 2.8 cm H2O and the total PEEP reached was 12.2 +/- 2.4 cm H2O. The degree of lung inflation induced by PEEP averaged 145 +/- 87 mL with PEEP = auto-PEEP and 495 +/- 133 mL with PEEP = auto-PEEP + 5. The PEEP = auto-PEEP caused a right ventricular end-diastolic pressure increase, but there was no other significant hemodynamic change. With PEEP = auto-PEEP + 5, there was a significant increase in intravascular pressures; this amount of PEEP reduced cardiac output (from 4.40 +/- 1.38 L/min at PEEP 0 to 4.13 +/- 1.48 L/min; p < .05). The cardiac output reduction induced by PEEP = auto-PEEP + 5 was > 10% in only five cases and this group of patients had significantly lower right ventricular volumes than the group with less cardiac output variation (right ventricular end-diastolic volume: 64 +/- 9 vs. 96 +/- 26 mL/m2; right ventricular end-systolic volume: 38 +/- 6 vs. 65 +/- 21 mL/m2; p < .05) without significant difference in the other variables that were measured. Neither right ventricular ejection fraction nor right ventricle volumes changed as PEEP increased, but there were marked interpatient differences and also pronounced changes in volume between stages in individual patients. In the study conditions, PEEP application up to values approaching auto-PEEP did not result in the impairment of right ventricular hemodynamics, while higher levels reduced cardiac output in selected patients.

"Pulmonary valve replacement diminishes the presence of restrictive physiology and reduces atrial volumes": a prospective study in Tetralogy of Fallot patients.

PubMed

Pijuan-Domenech, Antonia; Pineda, Victor; Castro, Miguel Angel; Sureda-Barbosa, Carlos; Ribera, Aida; Cruz, Luz M; Ferreira-Gonzalez, Ignacio; Dos-Subirà, Laura; Subirana-Domènech, Teresa; Garcia-Dorado, David; Casaldàliga-Ferrer, Jaume

2014-11-15

Pulmonary valve replacement (PVR) reduces right ventricular (RV) volumes in the setting of long-term pulmonary regurgitation after Tetralogy of Fallot (ToF) repair; however, little is known of its effect on RV diastolic function. Right atrial volumes may reflect the burden of RV diastolic dysfunction. The objective of this paper is to evaluate the clinical, echocardiographic, biochemical and cardiac magnetic resonance (CMR) variables, focusing particularly on right atrial response and right ventricular diastolic function prior to and after elective PVR in adult patients with ToF. This prospective study was conducted from January 2009 to April 2013 in consecutive patients > 18 years of age who had undergone ToF repair in childhood and were accepted for elective PVR. Twenty patients (mean age: 35 years; 70% men) agreed to enter the study. PVR was performed with a bioporcine prosthesis. Concomitant RV reduction was performed in all cases when technically possible. Pulmonary end-diastolic forward flow (EDFF) decreased significantly from 5.4 ml/m(2) to 0.3 ml/m(2) (p < 0.00001), and right atrial four-chamber echocardiographic measurements and volumes by 25% (p = 0.0024): mean indexed diastolic/systolic atrial volumes prior to surgery were 43 ml/m(2) (SD+/-4.6)/63 ml/m(2) (SD+/-5.5), and dropped to 33 ml/m(2) (SD+/-3)/46 ml/m(2) (SD+/-2.55) post-surgery. All patients presented right ventricular diastolic and systolic volume reductions, with a mean volume reduction of 35% (p < 0.00001). Right ventricular diastolic dysfunction was common in a population of severely dilated RV patients long term after ToF repair. Right ventricular diastolic parameters improved as did right atrial volumes in keeping with the known reduction in RV volumes, after PVR. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

3D ultrasound system to investigate intraventricular hemorrhage in preterm neonates

NASA Astrophysics Data System (ADS)

Kishimoto, J.; de Ribaupierre, S.; Lee, D. S. C.; Mehta, R.; St. Lawrence, K.; Fenster, A.

2013-11-01

Intraventricular hemorrhage (IVH) is a common disorder among preterm neonates that is routinely diagnosed and monitored by 2D cranial ultrasound (US). The cerebral ventricles of patients with IVH often have a period of ventricular dilation (ventriculomegaly). This initial increase in ventricle size can either spontaneously resolve, which often shows clinically as a period of stabilization in ventricle size and eventual decline back towards a more normal size, or progressive ventricular dilation that does not stabilize and which may require interventional therapy to reduce symptoms relating to increased intracranial pressure. To improve the characterization of ventricle dilation, we developed a 3D US imaging system that can be used with a conventional clinical US scanner to image the ventricular system of preterm neonates at risk of ventriculomegaly. A motorized transducer housing was designed specifically for hand-held use inside an incubator using a transducer commonly used for cranial 2D US scans. This system was validated using geometric phantoms, US/MRI compatible ventricle volume phantoms, and patient images to determine 3D reconstruction accuracy and inter- and intra-observer volume estimation variability. 3D US geometric reconstruction was found to be accurate with an error of <0.2%. Measured volumes of a US/MRI compatible ventricle-like phantom were within 5% of gold standard water displacement measurements. Intra-class correlation for the three observers was 0.97, showing very high agreement between observers. The coefficient of variation was between 1.8-6.3% for repeated segmentations of the same patient. The minimum detectable difference was calculated to be 0.63 cm3 for a single observer. Results from ANOVA for three observers segmenting three patients of IVH grade II did not show any significant differences (p > 0.05) for the measured ventricle volumes between observers. This 3D US system can reliably produce 3D US images of the neonatal ventricular system. There is the potential to use this system to monitor the progression of ventriculomegaly over time in patients with IVH.

A comparison of echocardiographic findings in young adults with cardiomyopathy: with and without a history of methamphetamine abuse.

PubMed

Ito, Hiroki; Yeo, Khung-Keong; Wijetunga, Mevan; Seto, Todd B; Tay, Kevin; Schatz, Irwin J

2009-06-01

Methamphetamine is currently the most widespread illegal stimulant abused in the United States. No previous reports comparing echocardiographic findings of cardiomyopathy with and without a history of methamphetamine abuse are available. We performed a single institution retrospective review of medical records and analyses of echocardiographic findings in patients < or = 45 years of age hospitalized between 2001 and 2004 who were discharged with a diagnosis of cardiomyopathy or heart failure. After exclusion of patients with coronary artery disease or severe cardiac valvular disease, the remaining patients were divided into 2 groups based on their abuse or non abuse of methamphetamine, as determined by the documented history in the medical records or urine toxicology testing. Among a total of 59 patients, 28 (47%) had a history of methamphetamine abuse or positive urine toxicology. Both methamphetamine abusers and non-abusers were predominately male (64.3% vs 64.5%, P = .99), and had a high prevalence of obesity (55.6% vs 73.3%, P = .16). Bivariate analysis revealed significant differences between the methamphetamine abusers and non-abusers in left atrium volume (119.7 +/- 55.4 ml vs 85.8 +/- 33.5 ml, P = .008), left ventricular end-diastolic volume (201.9 +/- 71.4 ml vs 156.6 +/- 63.1 ml, P = .01), left ventricular end-systolic volume (136.0 +/- 53.7 ml vs 92.3 +/- 55.8 ml, P = .004), right ventricular dimension (26.3 +/- 6.0 mm vs 21.3 +/- 6.0 mm, P = .007), and quantified left ventricular ejection fraction (32.9% +/- 11.3% vs 44.6% +/- 17.8%, P = .004). We found a high prevalence of methamphetamine abuse in our study population. Methamphetamine abusers had echocardiographic findings of more severe dilated cardiomyopathy compared with non-abusers. 2009 Wiley Periodicals, Inc.

Coupling of a 3D Finite Element Model of Cardiac Ventricular Mechanics to Lumped Systems Models of the Systemic and Pulmonic Circulation

PubMed Central

Kerckhoffs, Roy C. P.; Neal, Maxwell L.; Gu, Quan; Bassingthwaighte, James B.; Omens, Jeff H.; McCulloch, Andrew D.

2010-01-01

In this study we present a novel, robust method to couple finite element (FE) models of cardiac mechanics to systems models of the circulation (CIRC), independent of cardiac phase. For each time step through a cardiac cycle, left and right ventricular pressures were calculated using ventricular compliances from the FE and CIRC models. These pressures served as boundary conditions in the FE and CIRC models. In succeeding steps, pressures were updated to minimize cavity volume error (FE minus CIRC volume) using Newton iterations. Coupling was achieved when a predefined criterion for the volume error was satisfied. Initial conditions for the multi-scale model were obtained by replacing the FE model with a varying elastance model, which takes into account direct ventricular interactions. Applying the coupling, a novel multi-scale model of the canine cardiovascular system was developed. Global hemodynamics and regional mechanics were calculated for multiple beats in two separate simulations with a left ventricular ischemic region and pulmonary artery constriction, respectively. After the interventions, global hemodynamics changed due to direct and indirect ventricular interactions, in agreement with previously published experimental results. The coupling method allows for simulations of multiple cardiac cycles for normal and pathophysiology, encompassing levels from cell to system. PMID:17111210

Changes in mitral annular and left ventricular dimensions and left ventricular pressure-volume relations after off-pump treatment of mitral regurgitation with the Coapsys device.

PubMed

Fukamachi, Kiyotaka; Popović, Zoran B; Inoue, Masahiro; Doi, Kazuyoshi; Schenk, Soren; Ootaki, Yoshio; Kopcak, Michael W; McCarthy, Patrick M

2004-03-01

The objective of this study was to evaluate the changes in mitral annular and left ventricular dimensions and left ventricular pressure-volume relations produced by the Myocor Coapsys device that has been developed to treat functional mitral regurgitation (MR) off-pump. The Coapsys device, which consists of anterior and posterior epicardial pads connected by a sub-valvular chord, was implanted in seven dogs with functional MR resulting from pacing induced cardiomyopathy. The Coapsys device was then sized by drawing the posterior leaflet and annulus toward the anterior leaflet. During sizing, MR grade was assessed using color flow Doppler echocardiography. Final device size was selected when MR was eliminated or minimized. Following implantation, heart failure was maintained by continued pacing for a period of 8 weeks. Mitral annular and left ventricular dimensions and left ventricular pressure-volume relations were evaluated by two-dimensional echocardiography and a conductance catheter, respectively, at pre-sizing, post-sizing, and after 8 weeks. All implants were performed on beating hearts without cardiopulmonary bypass. Mean MR grade was reduced from 2.9+/-0.7 at pre-sizing to 0.7+/-0.8 at post-sizing (P<0.001), and was maintained at 0.8+/-0.8 after 8 weeks (P<0.01). The septal-lateral dimensions were significantly reduced at both mitral annular level [2.4+/-0.2 cm at pre-sizing, 1.5+/-0.3 cm at post-sizing (P<0.001) and 1.8+/-0.3 cm after 8 weeks (P<0.05)] and mid-papillary level [4.1+/-0.4 cm at pre-sizing, 2.4+/-0.2 cm at post-sizing (P<0.001) and 3.3+/-0.4 cm after 8 weeks (P<0.001)]. The end-systolic pressure-volume relation shifted leftward at post-sizing with a significantly steeper slope (P=0.03). There was a significant (P=0.03) leftward shift of the end-diastolic pressure-volume relation at post-sizing. After 8 weeks, these changes in pressure-volume relations tended to return to pre-sizing relations. The Coapsys device significantly reduced MR by treating both the mitral annular dilatation and the papillary muscle displacement. Despite these significant dimensional changes, the Coapsys device did not negatively affect the left ventricular pressure-volume relations.

Effect of prolonged space flight on cardiac function and dimensions

NASA Technical Reports Server (NTRS)

Henry, W. L.; Epstein, S. E.; Griffith, J. M.; Goldstein, R. E.; Redwood, D. R.

1974-01-01

Echocardiographic studies were performed preflight 5 days before launch and on recovery day and 1, 2, 4, 11, 31 and 68 days postflight. From these echocardiograms measurements were made. From these primary measurements, left ventricular end-diastolic volume, end-systolic volume, stroke volume, and mass were derived using the accepted assumptions. Findings in the Scientist Pilot and Pilot resemble those seen in trained distance runners. Wall thickness measurements were normal in all three crewmembers preflight. Postflight basal studies were unchanged in the Commander on recovery day through 68 days postflight in both the Scientist Pilot and Pilot, however, the left ventricular end-diastolic volume, stroke volume, and mass were decreased slightly. Left ventricular function curves were constructed for the Commander and Pilot by plotting stroke volume versus end-diastolic volume. In both astronauts, preflight and postflight data fell on the same straight line demonstrating that no deterioration in cardiac function had occurred. These data indicate that the cardiovascular system adapts well to prolonged weightlessness and suggest that alterations in cardiac dimensions and function are unlikely to limit man's future in space.

76 FR 48563 - Medicare and Medicaid Programs; Quarterly Listing of Program Issuances-January Through March 2011...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-08

...-7205 Ventricular Assist Device (Destination Therapy) Facilities. XIII Medicare-Approved Lung JoAnna...-Approved Ventricular Assist Device (Destination Therapy) Facilities, Addendum XIII: Lung Volume Reduction...-Approved Ventricular Assist Device (Destination Therapy) Facilities (January Through March 2011) Addendum...

Relationship between central and peripheral atherosclerosis and left ventricular dysfunction in a community population.

PubMed

Tsao, Connie W; Gona, Philimon; Salton, Carol; Murabito, Joanne M; Oyama, Noriko; Danias, Peter G; O'Donnell, Christopher J; Manning, Warren J; Yeon, Susan B

2011-08-01

We aimed to determine the relationships between resting left ventricular (LV) wall motion abnormalities (WMAs), aortic plaque, and peripheral artery disease (PAD) in a community cohort. A total of 1726 Framingham Heart Study Offspring Cohort participants (806 males, 65 ± 9 years) underwent cardiovascular magnetic resonance with quantification of aortic plaque volume and assessment of regional left ventricular systolic function. Claudication, lower extremity revascularization, and ankle-brachial index (ABI) were recorded at the most contemporaneous examination visit. WMAs were associated with greater aortic plaque burden, decreased ABI, and claudication in age- and sex-adjusted analyses (all p < 0.001), which were not significant after adjustment for cardiovascular risk factors. In age- and sex-adjusted analyses, both the presence (p < 0.001) and volume of aortic plaque were associated with decreased ABI (p < 0.001). After multivariable adjustment, an ABI ≤ 0.9 or prior revascularization was associated with a threefold odds of aortic plaque (p = 0.0083). Plaque volume significantly increased with decreasing ABI in multivariable-adjusted analyses (p < 0.0001). In this free-living population, associations of WMAs with aortic plaque burden and clinical measures of PAD were attenuated after adjustment for coronary heart disease risk factors. Aortic plaque volume and ABI remained strongly negatively correlated after multivariable adjustment. Our findings suggest that the association between coronary heart disease and non-coronary atherosclerosis is explained by cardiovascular risk factors. Aortic atherosclerosis and PAD remain strongly associated after multivariable adjustment, suggesting shared mechanisms beyond those captured by traditional risk factors.

Serial changes in anatomy and ventricular function on dual-source cardiac computed tomography after the Norwood procedure for hypoplastic left heart syndrome.

PubMed

Goo, Hyun Woo

2017-12-01

Accurate evaluation of anatomy and ventricular function after the Norwood procedure in hypoplastic left heart syndrome is important for treatment planning and prognostication, but echocardiography and cardiac MRI have limitations. To assess serial changes in anatomy and ventricular function on dual-source cardiac CT after the Norwood procedure for hypoplastic left heart syndrome. In 14 consecutive patients with hypoplastic left heart syndrome, end-systolic and end-diastolic phase cardiac dual-source CT was performed before and early (average: 1 month) after the Norwood procedure, and repeated late (median: 4.5 months) after the Norwood procedure in six patients. Ventricular functional parameters and indexed morphological measurements including pulmonary artery size, right ventricular free wall thickness, and ascending aorta size on cardiac CT were compared between different time points. Moreover, morphological features including ventricular septal defect, endocardial fibroelastosis and coronary ventricular communication were evaluated on cardiac CT. Right ventricular function and volumes remained unchanged (indexed end-systolic and end-diastolic volumes: 38.9±14.0 vs. 41.1±21.5 ml/m 2 , P=0.7 and 99.5±30.5 vs. 105.1±33.0 ml/m 2 , P=0.6; ejection fraction: 60.1±7.3 vs. 63.8±7.0%, P=0.1, and indexed stroke volume: 60.7±18.0 vs. 64.0±15.6 ml/m 2 , P=0.5) early after the Norwood procedure, but function was decreased (ejection fraction: 64.2±2.6 vs. 58.1±7.1%, P=0.01) and volume was increased (indexed end-systolic and end-diastolic volumes: 39.2±14.9 vs. 68.9±20.6 ml/m 2 , P<0.003 and 107.8±36.5 vs. 162.9±36.2 ml/m 2 , P<0.006, and indexed stroke volume: 68.6±21.7 vs. 94.0±21.3 ml/m 2 , P=0.02) later. Branch pulmonary artery size showed a gradual decrease without asymmetry after the Norwood procedure. Right and left pulmonary artery stenoses were identified in 21.4% (3/14) of the patients. Indexed right ventricular free wall thickness showed a significant increase early after the Norwood procedure (25.5±3.5 vs. 34.8±5.1 mm/m 2 , P=0.01) and then a significant decrease late after the Norwood procedure (34.8±5.1 vs. 27.2±4.2 mm/m 2 , P<0.0001). The hypoplastic ascending aorta smaller than 2 mm in diameter was identified in 21.4% (3/14) of the patients. Ventricular septal defect (n=3), endocardial fibroelastosis (n=2) and coronary ventricular communication (n=1) were detected on cardiac CT. Cardiac CT can be used to assess serial changes in anatomy and ventricular function after the Norwood procedure in patients with hypoplastic left heart syndrome.

Recovery from exercise at varying work loads - Time course of responses of heart rate and systolic intervals

NASA Technical Reports Server (NTRS)

Nandi, P. S.; Spodick, D. H.

1977-01-01

The time course of the recovery period was characterized by noninvasive measurements after 4 minute bicycle exercise at 3 separate work loads in volunteers with normal peak responses. Most responses started immediately to return toward resting control values. Left ventricular ejection time and stroke volume change are discussed. Changes in pre-ejection period were determined by changes in isovolume contraction time, and factors affecting the degree and rate of return are considered. The rates of change in the ejection time index and in the ratio pre-ejection period/left ventricular ejection time were virtually independent of load throughout most of recovery.

Effects of a prostagrandin EP4-receptor agonist ONO-AE1-329 on the left ventricular pressure-volume relationship in the halothane-anesthetized dogs.

PubMed

Honda, Atsushi; Nakamura, Yuji; Ohara, Hiroshi; Cao, Xin; Nomura, Hiroaki; Katagi, Jun; Wada, Takeshi; Izumi-Nakaseko, Hiroko; Ando, Kentaro; Sugiyama, Atsushi

2016-03-15

Cardiac effects of a prostagrandin EP4-receptor agonist ONO-AE1-329 were assessed in the halothane-anesthetized dogs under the monitoring of left ventricular pressure-volume relationship, which were compared with those of clinically recommended doses of dopamine, dobutamine and milrinone (n=4-5 for each treatment). ONO-AE1-329 was intravenously administered in doses of 0.3, 1 and 3 ng/kg/min for 10 min with a pause of 20 min. Dopamine in a dose of 3 µg/kg/min for 10 min, dobutamine in a dose of 1 µg/kg/min for 10 min and milrinone in a dose of 5 µg/kg/min for 10 min followed by 0.5 µg/kg/min for 10 min were intravenously administered. Low dose of ONO-AE1-329 increased the stroke volume. Middle dose of ONO-AE1-329 increased the cardiac output, left ventricular end-diastolic volume, ejection fraction, maximum upstroke/downstroke velocities of the left ventricular pressure and external work, but decreased the end-systolic pressure and internal work besides the change by the low dose. High dose of ONO-AE1-329 increased the heart rate and maximum elastance, but decreased the end-systolic volume besides the changes by the middle dose. Dopamine, dobutamine and milrinone exerted essentially similar cardiac effects to ONO-AE1-329, but they did not significantly change the end-diastolic volume, end-systolic volume, stroke volume, ejection fraction, end-systolic pressure, maximum elastance, external work or internal work. Thus, EP4-receptor stimulation by ONO-AE1-329 may have potential to better promote the passive ventricular filling than the conventional cardiotonic drugs, which could become a candidate of novel therapeutic strategy for the treatment of heart failure with preserved ejection fraction. Copyright © 2016 Elsevier B.V. All rights reserved.

New digital measurement methods for left ventricular volume using real-time three-dimensional echocardiography: comparison with electromagnetic flow method and magnetic resonance imaging

NASA Technical Reports Server (NTRS)

Qin, J. J.; Jones, M.; Shiota, T.; Greenberg, N. L.; Firstenberg, M. S.; Tsujino, H.; Zetts, A. D.; Sun, J. P.; Cardon, L. A.; Odabashian, J. A.;

Fornix Under Water? Ventricular Enlargement Biases Forniceal Diffusion Magnetic Resonance Imaging Indices in Anorexia Nervosa.

PubMed

Kaufmann, Lisa-Katrin; Baur, Volker; Hänggi, Jürgen; Jäncke, Lutz; Piccirelli, Marco; Kollias, Spyros; Schnyder, Ulrich; Pasternak, Ofer; Martin-Soelch, Chantal; Milos, Gabriella

2017-07-01

Acute anorexia nervosa (AN) is characterized by reduced brain mass and corresponding increased sulcal and ventricular cerebrospinal fluid. Recent studies of white matter using diffusion tensor imaging consistently identified alterations in the fornix, such as reduced fractional anisotropy (FA). However, because the fornix penetrates the ventricles, it is prone to cerebrospinal fluid-induced partial volume effects that interfere with a valid assessment of FA. We investigated the hypothesis that in the acute stage of AN, FA of the fornix is markedly affected by ventricular volumes. First, using diffusion tensor imaging data we established the inverse associations between forniceal FA and volumes of the third and lateral ventricles in a prestudy with 32 healthy subjects to demonstrate the strength of ventricular influence on forniceal FA independent of AN. Second, we investigated a sample of 25 acute AN patients and 25 healthy control subjects. Using ventricular volumes as covariates markedly reduced the group effect of forniceal FA, even with tract-based spatial statistics focusing only on the center of the fornix. In addition, after correcting for free water on voxel level, the group differences in forniceal FA between AN patients and controls disappeared completely. It is unlikely that microstructural changes affecting FA occurred in the fornix of AN patients. Previously identified alterations in acute AN may have been biased by partial volume effects and the proposed central role of this structure in the pathophysiology may need to be reconsidered. Future studies on white matter alterations in AN should carefully deal with partial volume effects. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Do we overestimate left ventricular ejection fraction by two-dimensional echocardiography in patients with left bundle branch block?

PubMed

Cabuk, Ali K; Cabuk, Gizem; Sayin, Ahmet; Karamanlioglu, Murat; Kilicaslan, Barış; Ekmekci, Cenk; Solmaz, Hatice; Aslanturk, Omer F; Ozdogan, Oner

2018-02-01

Left bundle branch block (LBBB) causes a dyssynchronized contraction of left ventricle. This is a kind of regional wall-motion abnormality and measuring left ventricular ejection fraction (LVEF) by two-dimensional (2D) echocardiography could be less reliable in this particular condition. Our aim was to evaluate the role of dyssynchrony index (SDI), measured by three-dimensional (3D) echocardiography, in assessment of LVEF and left ventricular volumes accurately in patients with LBBB. In this case-control study, we included 52 of 64 enrolled participants (twelve participants with poor image quality were excluded) with LBBB and normal LVEF or nonischemic cardiomyopathy. Left ventricular ejection fraction (LVEF) and left ventricular volumes were assessed by 2D (modified Simpson's rule) and 3D (four beats full volume analysis) echocardiography and the impact of SDI on results were evaluated. In patients with SDI ≥6%, LVEF measurements were significantly different (46.00% [29.50-52.50] vs 37.60% [24.70-45.15], P < .001) between 2D and 3D echocardiography, respectively. In patients with SDI < 6%, there were no significant differences between two modalities in terms of LVEF measurements (54.50% [49.00-59.00] vs 54.25% [40.00-58.25], P = .193). LV diastolic volumes were not significantly different while systolic volumes were underestimated by 2D echocardiography, and this finding was more pronounced when SDI ≥ 6%. In patients with LBBB and high SDI (≥6%), LVEF values were overestimated and systolic volumes were underestimated by 2D echocardiography compared to 3D echocardiography. © 2017 Wiley Periodicals, Inc.

Optoelectronic system for the determination of blood volume in pneumatic heart assist devices.

PubMed

Konieczny, Grzegorz; Pustelny, Tadeusz; Setkiewicz, Maciej; Gawlikowski, Maciej

2015-12-10

The following article describes the concept of optical measurement of blood volume in ventricular assist devices (VAD's) of the pulsatile type. The paper presents the current state of art in blood volume measurements of such devices and introduces a newly developed solution in the optic domain. The objective of the research is to overcome the disadvantages of the previously developed acoustic method-the requirement of additional sensor chamber. The idea of a compact measurement system has been introduced, followed by laboratory measurements. Static tests of the system have been presented, followed by dynamic measurements on a physical model of the human ventricular system. The results involving the measurements of blood chamber volume acquired by means of an optical system have been compared with the results acquired by means of the Transonic T410 ultrasound flow rate sensor (11PLX transducer, uncertainty ±5 %). Preliminary dynamic measurements conducted on the physical model of the human cardiovascular system show that the proposed optical measurement system may be used to measure the transient blood chamber volumes of pulsatile VAD's with the uncertainties (standard mean deviation) lower than 10 %. The results show that the noninvasive measurements of the temporary blood chamber volume in the POLVAD prosthesis with the use of the developed optical system allows us to carry out accurate static and dynamic measurements.

Quantitation of aortic and mitral regurgitation in the pediatric population: evaluation by radionuclide angiocardiography

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

Hurwitz, R.A.; Treves, S.; Freed, M.

The ability to quantitate aortic (AR) or mitral regurgitation (MR), or both, by radionuclide angiocardiography was evaluated in children and young adults at rest and during isometric exercise. Regurgitation was estimated by determining the ratio of left ventricular stroke volume to right ventricular stroke volume obtained during equilibrium ventriculography. The radionuclide measurement was compared with results of cineangiography, with good correlation between both studies in 47 of 48 patients. Radionuclide stroke volume ratio was used to classify severity: the group with equivocal regurgitation differed from the group with mild regurgitation (p less than 0.02); patients with mild regurgitation differed frommore » those with moderate regurgitation (p less than 0.001); and those with moderate regurgitation differed from those with severe regurgitation (p less than 0.01). The stroke volume ratio was responsive to isometric exercise, remaining constant or increasing in 16 of 18 patients. After surgery to correct regurgitation, the stroke volume ratio significantly decreased from preoperative measurements in all 7 patients evaluated. Results from the present study demonstrate that a stroke volume ratio greater than 2.0 is compatible with moderately severe regurgitation and that a ratio greater than 3.0 suggests the presence of severe regurgitation. Thus, radionuclide angiocardiography should be useful for noninvasive quantitation of AR or MR, or both, helping define the course of young patients with left-side valvular regurgitation.« less

Age-related differences in the structural complexity of subcortical and ventricular structures.

PubMed

Madan, Christopher R; Kensinger, Elizabeth A

2017-02-01

It has been well established that the volume of several subcortical structures decreases in relation to age. Different metrics of cortical structure (e.g., volume, thickness, surface area, and gyrification) have been shown to index distinct characteristics of interindividual differences; thus, it is important to consider the relation of age to multiple structural measures. Here, we compare age-related differences in subcortical and ventricular volume to those differences revealed with a measure of structural complexity, quantified as fractal dimensionality. Across 3 large data sets, totaling nearly 900 individuals across the adult lifespan (aged 18-94 years), we found greater age-related differences in complexity than volume for the subcortical structures, particularly in the caudate and thalamus. The structural complexity of ventricular structures was not more strongly related to age than volume. These results demonstrate that considering shape-related characteristics improves sensitivity to detect age-related differences in subcortical structures. Copyright © 2016 Elsevier Inc. All rights reserved.

Right ventricular longitudinal strain and right ventricular stroke work index in patients with severe heart failure: left ventricular assist device suitability for transplant candidates.

PubMed

Cameli, M; Bernazzali, S; Lisi, M; Tsioulpas, C; Croccia, M G; Lisi, G; Maccherini, M; Mondillo, S

2012-09-01

Right ventricular (RV) systolic function has a critical role in determining the clinical outcome and the success of using left ventricular assist devices in patients with refractory heart failure. RV deformation analysis by speckle tracking echocardiography (STE) has recently allowed the analysis of RV longitudinal function. Using cardiac catheterization as the reference standard, this study aimed to explore the correlation between RV longitudinal function by STE and RV stroke work index (RVSWI) among patients referred for cardiac transplantation. Right heart catheterization and transthoracic echo-Doppler were simultaneously performed in 47 patients referred for cardiac transplant assessment due to refractory heart failure (ejection fraction 25.1 ± 4.5%). Thermodilution RV stroke volume and invasive pulmonary pressures were used to obtain RVSWI. RV longitudinal strain (RVLS) by STE was assessed averaging RV free-wall segments (free-wall RVLS). We also calculated. Tricuspid S' and tricuspid annular plane systolic excursion (TAPSE). No significant correlation was observed for TAPSE on tricuspid S' with RV stroke volume (r = 0.14 and r = 0.06, respectively). A close negative correlation between free-wall RVLS and RVSWI was found (r = -0.82; P < .0001). Furthermore, free-wall RVLS showed the highest diagnostic accuracy (area under the curve of 0.90) with good sensitivity and specificity of 95% and 91%, respectively, to predict depressed RVSWI using a cutoff value less than -11.8%. Among patients referred for heart transplantation, TAPSE and tricuspid S' did not correlate with invasively obtained RVSWI. RV longitudinal deformation analysis by STE correlated with RVSWI, providing a better estimate of RV systolic performance. Copyright © 2012 Elsevier Inc. All rights reserved.

Accuracy of external ventricular drainage catheter placement.

PubMed

Abdoh, Mohammad Ghazi; Bekaert, Olivier; Hodel, Jérôme; Diarra, Salia Mamadou; Le Guerinel, Caroline; Nseir, Rémi; Bastuji-Garin, Sylvie; Decq, Philippe

2012-01-01

External ventricular drainage (EVD) is a freehand neurosurgical procedure performed routinely using the anatomical landmarks. The aim of this study was to determine the accuracy of EVD catheter freehand placement. Pre-operative and post-operative computed tomography scans for 66 consecutive EVDs performed in 56 adult patients (26 men, 30 women) in 2008 were retrospectively reviewed. Etiologies of acute hydrocephalus were subarachnoid or intraventricular haemorrhage (43 cases) or miscellaneous (13 cases). Pre-operative lateral ventricular volume, position of the burr hole, length of the catheter and its sagittal and coronal angular variations from a theoretical trajectory were measured. The EVD was placed on the right (53 cases) or left (13 cases) side. The mean pre-operative lateral ventricular volume was 51 cc (10-118 cc). The average distance from the burr hole to the midline was 28 mm (10-49 mm) and to the supra-orbital ridge was 101 mm (75-125 mm). The mean intracranial catheter length was 60 mm (from 39-102 mm). Only 50% of the EVDs in the coronal plane and 40% in the sagittal plane were placed with an angular variation of ±5° to the target. The tip was placed outside of the ventricles in three cases; 13 catheters crossed the midline, and five intracranial minor haemorrhages were detected. Freehand placement of EVDs does not have sufficient accuracy and may lead to drainage dysfunctions. This data suggests that a guidance system for EVD's would be required.

Clinical application of a light-pen computer system for quantitative angiography

NASA Technical Reports Server (NTRS)

Alderman, E. L.

1975-01-01

The paper describes an angiographic analysis system which uses a video disk for recording and playback, a light-pen for data input, minicomputer processing, and an electrostatic printer/plotter for hardcopy output. The method is applied to quantitative analysis of ventricular volumes, sequential ventriculography for assessment of physiologic and pharmacologic interventions, analysis of instantaneous time sequence of ventricular systolic and diastolic events, and quantitation of segmental abnormalities. The system is shown to provide the capability for computation of ventricular volumes and other measurements from operator-defined margins by greatly reducing the tedium and errors associated with manual planimetry.

Quantification of Left Ventricular Linear, Areal and Volumetric Dimensions: A Phantom and in Vivo Comparison of 2-D and Real-Time 3-D Echocardiography with Cardiovascular Magnetic Resonance.

PubMed

Polte, Christian L; Lagerstrand, Kerstin M; Gao, Sinsia A; Lamm, Carl R; Bech-Hanssen, Odd

2015-07-01

Two-dimensional echocardiography and real-time 3-D echocardiography have been reported to underestimate human left ventricular volumes significantly compared with cardiovascular magnetic resonance. We investigated the ability of 2-D echocardiography, real-time 3-D echocardiography and cardiovascular magnetic resonance to delineate dimensions of increasing complexity (diameter-area-volume) in a multimodality phantom model and in vivo, with the aim of elucidating the main cause of underestimation. All modalities were able to delineate phantom dimensions with high precision. In vivo, 2-D and real-time 3-D echocardiography underestimated short-axis end-diastolic linear and areal and all left ventricular volumetric dimensions significantly compared with cardiovascular magnetic resonance, but not short-axis end-systolic linear and areal dimensions. Underestimation increased successively from linear to volumetric left ventricular dimensions. When analyzed according to the same principles, 2-D and real-time 3-DE echocardiography provided similar left ventricular volumes. In conclusion, echocardiographic underestimation of left ventricular dimensions is due mainly to inherent technical differences in the ability to differentiate trabeculated from compact myocardium. Identical endocardial border definition criteria are needed to minimize differences between the modalities and to ensure better comparability in clinical practice. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Effects of passive heating on central blood volume and ventricular dimensions in humans

PubMed Central

Crandall, C G; Wilson, T E; Marving, J; Vogelsang, T W; Kjaer, A; Hesse, B; Secher, N H

2008-01-01

Mixed findings regarding the effects of whole-body heat stress on central blood volume have been reported. This study evaluated the hypothesis that heat stress reduces central blood volume and alters blood volume distribution. Ten healthy experimental and seven healthy time control (i.e. non-heat stressed) subjects participated in this protocol. Changes in regional blood volume during heat stress and time control were estimated using technetium-99m labelled autologous red blood cells and gamma camera imaging. Whole-body heating increased internal temperature (≥ 1.0°C), cutaneous vascular conductance (approximately fivefold), and heart rate (52 ± 2 to 93 ± 4 beats min−1), while reducing central venous pressure (5.5 ± 07 to 0.2 ± 0.6 mmHg) accompanied by minor decreases in mean arterial pressure (all P < 0.05). The heat stress reduced the blood volume of the heart (18 ± 2%), heart plus central vasculature (17 ± 2%), thorax (14 ± 2%), inferior vena cava (23 ± 2%) and liver (23 ± 2%) (all P≤ 0.005 relative to time control subjects). Radionuclide multiple-gated acquisition assessment revealed that heat stress did not significantly change left ventricular end-diastolic volume, while ventricular end-systolic volume was reduced by 24 ± 6% of pre-heat stress levels (P < 0.001 relative to time control subjects). Thus, heat stress increased left ventricular ejection fraction from 60 ± 1% to 68 ± 2% (P= 0.02). We conclude that heat stress shifts blood volume from thoracic and splanchnic regions presumably to aid in heat dissipation, while simultaneously increasing heart rate and ejection fraction. PMID:17962331

STAR (Simple Targeted Arterial Rendering) Technique: a Novel and Simple Method to Visualize the Fetal Cardiac Outflow Tracts

PubMed Central

Yeo, Lami; Romero, Roberto; Jodicke, Cristiano; Kim, Sun Kwon; Gonzalez, Juan M.; Oggè, Giovanna; Lee, Wesley; Kusanovic, Juan Pedro; Vaisbuch, Edi; Hassan, Sonia S.

2010-01-01

Objective To describe a novel and simple technique (STAR: Simple Targeted Arterial Rendering) to visualize the fetal cardiac outflow tracts from dataset volumes obtained with spatiotemporal image correlation (STIC) and applying a new display technology (OmniView). Methods We developed a technique to image the outflow tracts by drawing three dissecting lines through the four-chamber view of the heart contained in a STIC volume dataset. Each line generated the following plane: 1) Line 1: ventricular septum “en face” with both great vessels (pulmonary artery anterior to the aorta); 2) Line 2: pulmonary artery with continuation into the longitudinal view of the ductal arch; and 3) Line 3: long axis view of the aorta arising from the left ventricle. The pattern formed by all 3 lines intersecting approximately through the crux of the heart resembles a “star”. The technique was then tested in 50 normal hearts (15.3 – 40.4 weeks of gestation). To determine if the technique could identify planes that departed from the normal images, we tested the technique in 4 cases with proven congenital heart defects (ventricular septal defect, transposition of great vessels, tetralogy of Fallot, and pulmonary atresia with intact ventricular septum). Results The STAR technique was able to generate the intended planes in all 50 normal cases. In the abnormal cases, the STAR technique allowed identification of the ventricular septal defect, demonstrated great vessel anomalies, and displayed views that deviated from what was expected from the examination of normal hearts. Conclusions This novel and simple technique can be used to visualize the outflow tracts and ventricular septum “en face” in normal fetal hearts. The inability to obtain expected views or the appearance of abnormal views in the generated planes should raise the index of suspicion for congenital heart disease involving the great vessels and/or the ventricular septum. The STAR technique may simplify examination of the fetal heart and could reduce operator dependency. PMID:20878672

Pulmonary hypertension in dogs with mitral regurgitation attributable to myxomatous valve disease.

PubMed

Chiavegato, David; Borgarelli, Michele; D'Agnolo, Gino; Santilli, Roberto A

2009-01-01

Pulmonary hypertension has been associated with mitral insufficiency caused by chronic degenerative valve disease in dogs. Our aim was to search for associations between left atrial to aortic root ratio, end-systolic and end-diastolic volume indices, and changes in the right ventricular to right atrial pressure gradient as estimated by the peak velocity of tricuspid regurgitation in dogs with chronic degenerative valve disease and different classes of heart failure. Dogs, for which follow-up was available were evaluated for changes in the right ventricular to right atrial systolic pressure gradient over time. Three hundred and forty-four dogs were studied; 51 in the International Small Animal Cardiac Health Council class la, 75 in class 1b, 113 in class 2, 97 in class 3a, and 8 in class 3b. The mean values for right ventricular to right atrial systolic pressure gradient, end-systolic volume index, end-diastolic volume index, and left atrial to aortic ratio were 49.2 +/- 17.1 mmHg, 149.12 +/- 60.8 and 37.7 +/- 21.6 ml/m2, and 1.9 +/- 0.5, respectively. A weak positive correlation was found between the right ventricular to right atrial systolic pressure gradient and the left atrial to aorta ratio (r = 0.242, P < 0.0001), end-diastolic volume index (r = 0.242, P < 0.0001), and end-systolic volume index (r = 0.129, P < 0.001). Follow up was available for 49 dogs. Of these, 18 had an increased, 12 a decreased, and 19 a stable right ventricular to right atrial systolic pressure gradient despite therapy. The equivalence point between the sensitivity and specificity curves of about 80% in the coincident point corresponded to a right ventricular to right atrial systolic pressure gradient of 48 mmHg. Our results suggest an association between the progressive nature of chronic degenerative mitral valve disease and pulmonary hypertension. It is of clinical interest that, with a right ventricular to right atrial systolic pressure gradient pressure gradient at or above 48 mmHg, pulmonary hypertension does not appear to improve despite therapy targeted at lowering the left atrial load.

Systolic ventricular filling.

PubMed

Torrent-Guasp, Francisco; Kocica, Mladen J; Corno, Antonio; Komeda, Masashi; Cox, James; Flotats, A; Ballester-Rodes, Manel; Carreras-Costa, Francesc

2004-03-01

The evidence of the ventricular myocardial band (VMB) has revealed unavoidable coherence and mutual coupling of form and function in the ventricular myocardium, making it possible to understand the principles governing electrical, mechanical and energetical events within the human heart. From the earliest Erasistratus' observations, principal mechanisms responsible for the ventricular filling have still remained obscured. Contemporary experimental and clinical investigations unequivocally support the attitude that only powerful suction force, developed by the normal ventricles, would be able to produce an efficient filling of the ventricular cavities. The true origin and the precise time frame for generating such force are still controversial. Elastic recoil and muscular contraction were the most commonly mentioned, but yet, still not clearly explained mechanisms involved in the ventricular suction. Classical concepts about timing of successive mechanical events during the cardiac cycle, also do not offer understandable insight into the mechanism of the ventricular filling. The net result is the current state of insufficient knowledge of systolic and particularly diastolic function of normal and diseased heart. Here we summarize experimental evidence and theoretical backgrounds, which could be useful in understanding the phenomenon of the ventricular filling. Anatomy of the VMB, and recent proofs for its segmental electrical and mechanical activation, undoubtedly indicates that ventricular filling is the consequence of an active muscular contraction. Contraction of the ascendent segment of the VMB, with simultaneous shortening and rectifying of its fibers, produces the paradoxical increase of the ventricular volume and lengthening of its long axis. Specific spatial arrangement of the ascendent segment fibers, their interaction with adjacent descendent segment fibers, elastic elements and intra-cavitary blood volume (hemoskeleton), explain the physical principles involved in this action. This contraction occurs during the last part of classical systole and the first part of diastole. Therefore, the most important part of ventricular diastole (i.e. the rapid filling phase), in which it receives >70% of the stroke volume, belongs to the active muscular contraction of the ascendent segment. We hope that these facts will give rise to new understanding of the principal mechanisms involved in normal and abnormal diastolic heart function.

Association between central sleep apnea and left ventricular structure: the Multi-Ethnic Study of Atherosclerosis.

PubMed

Javaheri, Sogol; Sharma, Ravi K; Bluemke, David A; Redline, Susan

2017-08-01

We assessed whether the presence of central sleep apnea is associated with adverse left ventricular structural changes. We analysed 1412 participants from the Multi-Ethnic Study of Atherosclerosis who underwent both overnight polysomnography and cardiac magnetic resonance imaging. Subjects had been recruited 10 years earlier when free of cardiovascular disease. Our main exposure is the presence of central sleep apnea as defined by central apnea-hypopnea index = 5 or the presence of Cheyne-Stokes breathing. Outcome variables were left ventricular mass/height, left ventricular ejection fraction, and left ventricular mass/volume ratio. Multivariate linear regression models adjusted for age, gender, race, waist circumference, tobacco use, hypertension, and the obstructive apnea-hypopnea index were fit for the outcomes. Of the 1412 participants, 27 (2%) individuals had central sleep apnea. After adjusting for covariates, the presence of central sleep apnea was significantly associated with elevated left ventricular mass/volume ratio (β = 0.11 ± 0.04 g mL -1 , P = 0.0071), an adverse cardiac finding signifying concentric remodelling. © 2017 European Sleep Research Society.

[Preoperative and follow-up cardiac magnetic resonance imaging of candidates for surgical ventricular restoration].

PubMed

Rodríguez Masi, M; Martín Lores, I; Bustos García de Castro, A; Cabeza Martínez, B; Maroto Castellanos, L; Gómez de Diego, J; Ferreirós Domínguez, J

2016-01-01

To assess pre and post-operative cardiac MRI (CMR) findings in patients with left endoventriculoplasty repair for ventricular aneurysm due to ischemic heart disease. Data were retrospectively gathered on 21 patients with diagnosis of ventricular aneurysm secondary to ischemic heart disease undergoing left endoventriculoplasty repair between January 2007 and March 2013. Pre and post-operative CMR was performed in 12 patients. The following data were evaluated in pre-operative and post-operative CMR studies: quantitative analysis of left ventricular ejection fraction (LVEF), left ventricular end-diastolic (LVEDV) and end-systolic (LVESV) volume index, presence of valvular disease and intracardiac thrombi. The time between surgery and post-operative CRM studies was 3-24 months. Significant differences were found in the pre and post-operative LVEF, LVEDV and LVESV data. EF showed a median increase of 10% (IQR 2-15) (p=0.003). The LVEDV showed a median decrease of 38 ml/m(2) (IQR 18-52) (p=0.006) and the LVESV showed a median decrease of 45 ml/m(2) (IQR:12-60) (p=0.008). Post-operative ventricular volume reduction was significantly higher in those patients with preoperative LVESV >110 ml/m(2) (59 ml/m(2) and 12 ml/m(2), p=0.006). In patients with ischemic heart disease that are candidates for left endoventriculoplasty, CMR is a reliable non-invasive and reproducible technique for the evaluation of the scar before the surgery and the ventricular volumes and its evolution after endoventricular surgical repair. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Lung Deflation and Cardiovascular Structure and Function in Chronic Obstructive Pulmonary Disease. A Randomized Controlled Trial.

PubMed

Stone, Ian S; Barnes, Neil C; James, Wai-Yee; Midwinter, Dawn; Boubertakh, Redha; Follows, Richard; John, Leonette; Petersen, Steffen E

2016-04-01

Patients with chronic obstructive pulmonary disease develop increased cardiovascular morbidity with structural alterations. To investigate through a double-blind, placebo-controlled, crossover study the effect of lung deflation on cardiovascular structure and function using cardiac magnetic resonance. Forty-five hyperinflated patients with chronic obstructive pulmonary disease were randomized (1:1) to 7 (maximum 14) days inhaled corticosteroid/long-acting β2-agonist fluticasone furoate/vilanterol 100/25 μg or placebo (7-day minimum washout). Primary outcome was change from baseline in right ventricular end-diastolic volume index versus placebo. There was a 5.8 ml/m(2) (95% confidence interval, 2.74-8.91; P < 0.001) increase in change from baseline right ventricular end-diastolic volume index and a 429 ml (P < 0.001) reduction in residual volume with fluticasone furoate/vilanterol versus placebo. Left ventricular end-diastolic and left atrial end-systolic volumes increased by 3.63 ml/m(2) (P = 0.002) and 2.33 ml/m(2) (P = 0.002). In post hoc analysis, right ventricular stroke volume increased by 4.87 ml/m(2) (P = 0.003); right ventricular ejection fraction was unchanged. Left ventricular adaptation was similar; left atrial ejection fraction improved by +3.17% (P < 0.001). Intrinsic myocardial function was unchanged. Pulmonary artery pulsatility increased in two of three locations (main +2.9%, P = 0.001; left +2.67%, P = 0.030). Fluticasone furoate/vilanterol safety profile was similar to placebo. Pharmacologic treatment of chronic obstructive pulmonary disease has consistent beneficial and plausible effects on cardiac function and pulmonary vasculature that may contribute to favorable effects of inhaled therapies. Future studies should investigate the effect of prolonged lung deflation on intrinsic myocardial function. Clinical trial registered with www.clinicaltrials.gov (NCT 01691885).

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.

Aerobic training in adults after atrial switch procedure for transposition of the great arteries improves exercise capacity without impairing systemic right ventricular function.

PubMed

Westhoff-Bleck, Mechthild; Schieffer, Bernhard; Tegtbur, Uwe; Meyer, Gerd Peter; Hoy, Ludwig; Schaefer, Arnd; Tallone, Ezequiel Marcello; Tutarel, Oktay; Mertins, Ramona; Wilmink, Lena Mara; Anker, Stefan D; Bauersachs, Johann; Roentgen, Philipp

2013-12-05

Exercise training safely and efficiently improves symptoms in patients with heart failure due to left ventricular dysfunction. However, studies in congenital heart disease with systemic right ventricle are scarce and results are controversial. In a randomised controlled study we investigated the effect of aerobic exercise training on exercise capacity and systemic right ventricular function in adults with d-transposition of the great arteries after atrial redirection surgery (28.2 ± 3.0 years after Mustard procedure). 48 patients (31 male, age 29.3 ± 3.4 years) were randomly allocated to 24 weeks of structured exercise training or usual care. Primary endpoint was the change in maximum oxygen uptake (peak VO2). Secondary endpoints were systemic right ventricular diameters determined by cardiac magnetic resonance imaging (CMR). Data were analysed per intention to treat analysis. At baseline peak VO2 was 25.5 ± 4.7 ml/kg/min in control and 24.0 ± 5 ml/kg/min in the training group (p=0.3). Training significantly improved exercise capacity (treatment effect for peak VO2 3.8 ml/kg/min, 95% CI: 1.8 to 5.7; p=0.001), work load (p=0.002), maximum exercise time (p=0.002), and NYHA class (p=0.046). Systemic ventricular function and volumes determined by CMR remained unchanged. None of the patients developed signs of cardiac decompensation or arrhythmias while on exercise training. Aerobic exercise training did not detrimentally affect systemic right ventricular function, but significantly improved exercise capacity and heart failure symptoms. Aerobic exercise training can be recommended for patients following atrial redirection surgery to improve exercise capacity and to lessen or prevent heart failure symptoms. ( ClinicalTrials.gov #NCT00837603). © 2013.

Ongoing right ventricular hemodynamics in heart failure: clinical value of measurements derived from an implantable monitoring system.

PubMed

Adamson, Philip B; Magalski, Anthony; Braunschweig, Frieder; Böhm, Michael; Reynolds, Dwight; Steinhaus, David; Luby, Allyson; Linde, Cecilia; Ryden, Lars; Cremers, Bodo; Takle, Teri; Bennett, Tom

2003-02-19

This study examined the characteristics of continuously measured right ventricular (RV) hemodynamic information derived from an implantable hemodynamic monitor (IHM) in heart failure patients. Hemodynamic monitoring might improve the day-to-day management of patients with chronic heart failure (CHF). Little is known about the characteristics of long-term hemodynamic information in patients with CHF or how such information relates to meaningful clinical events. Thirty-two patients with CHF received a permanent RV IHM system similar to a single-lead pacemaker. Right ventricular systolic and diastolic pressures, heart rate, and pressure derivatives were continuously measured for nine months without using the data for clinical decision-making or management of patients. Data were then made available to clinical providers, and the patients were followed up for 17 months. Pressure characteristics during optimal volume, clinically determined volume-overload exacerbations, and volume depletion events were examined. The effect of IHM on hospitalizations was examined using the patients' historical controls. Long-term RV pressure measurements had either marked variability or minimal time-related changes. During 36 volume-overload events, RV systolic pressures increased by 25 +/- 4% (p < 0.05) and heart rate increased by 11 +/- 2% (p < 0.05). Pressure increases occurred in 9 of 12 events 4 +/- 2 days before the exacerbations requiring hospitalization. Hospitalizations before using IHM data for clinical management averaged 1.08 per patient year and decreased to 0.47 per patient-year (57% reduction, p < 0.01) after hemodynamic data were used. Long-term ambulatory pressure measurements from an IHM may be helpful in guiding day-to-day clinical management, with a potentially favorable impact on CHF hospitalizations.

True Anemia-Red Blood Cell Volume Deficit-in Heart Failure: A Systematic Review.

PubMed

Montero, David; Lundby, Carsten; Ruschitzka, Frank; Flammer, Andreas J

2017-05-01

Anemia in heart failure (HF) is commonly diagnosed according to hemoglobin concentration [Hb], hence may be the result of hemodilution or true red blood cell volume (RBCV) deficit. Whether true (nonhemodilutional) anemia in HF can or cannot be generally inferred by [Hb] measurements and clinical correlates remains unclear. The purpose of this study was to systematically review the literature and investigate the status and correlates of RBCV in patients with HF. MEDLINE, Scopus, and Web of Science were searched since their inceptions until April 2016 for articles directly reporting or allowing the calculation of intravascular volumes (RBCV, plasma volume) in patients with HF according to the International Council for Standardization in Hematology. Eighteen studies were included after systematic review, comprising a total of 368 patients with HF (limits for mean age=49-80 years, sex=0%-92% females, left ventricular ejection fraction=26%-61%). Mean RBCV was reduced (limits=67%-88% of normal) in all studies including HF patients with anemia (low [Hb]) (7 studies, n=127), whereas only 2 of 10 studies in nonanemic patients with HF presented lower than normal mean RBCV (90% and 96%). In metaregression analyses, RBCV was positively associated with [Hb] ( B =6.10, SE=1.44) and negatively associated with age ( B =-1.14, SE=0.23), % females ( B =-0.38, SE=0.04), left ventricular ejection fraction ( B =-0.81, SE=0.20), and body mass index ( B =-3.55, SE=0.46; P <0.001). Presence or absence of true anemia in patients with HF as determined by RBCV status mainly concurs with diagnosis based on [Hb] and presents negative relationships with age, female sex, left ventricular ejection fraction, and body mass index. © 2017 American Heart Association, Inc.

Echocardiographic diagnosis of left ventricular-right atrial communication (Gerbode-type defect) in an adult with chronic renal failure: a case report.

PubMed

Eroglu, Serpil; Sade, Elif; Bozbas, Huseyin; Pirat, Bahar; Yildirir, Aylin; Muderrisoglu, Haldun

2008-03-01

Left ventricular-right atrial communication, known as a Gerbode-type defect, is a rare form of ventricular septal defect. It is usually congenital, but rarely acquired. Clinical presentation is associated with the volume of the shunt. Transthoracic echocardiography is the most useful diagnostic method. We present a 63-year-old man with chronic renal failure and left ventricular-right atrial shunt.

Comparison of magnetic resonance imaging with cross-sectional echocardiography in the assessment of left ventricular mass in children without heart disease and in aortic isthmic coarctation.

PubMed

Vogel, M; Stern, H; Bauer, R; Bühlmeyer, K

1992-04-01

Although left ventricular (LV) mass may be important to judge effects of left-sided cardiac obstruction or hypertension, reproducible noninvasively determined normal data in the pediatric age group are scarce. To validate cross-sectional echocardiographic LV mass determination, our data were compared with LV mass assessed by magnetic resonance imaging (MRI). MRI was considered to be a good reference method because there is usually no problem in defining endo- and epicardial borders with MRI. LV mass was assessed in 14 children aged 5.3 years (10 days to 14.7 years) with a mean body surface area of 0.78 m2 (range 0.25 to 1.61). With cross-sectional echocardiography the epicardial and endocardial volumes were calculated using a Simpsons rule algorithm in the apical 2- and 4-chamber view. The difference between epi- and endocardial volumes was multiplied by 1.05 to yield the mass. Mass was assessed with MRI using a multislice technique; the area of each myocardial slice was calculated and multiplied with the slice thickness, and the resultant slice volumes were added to obtain the myocardial volume. On cross-sectional echocardiography, the mass was 55 g (range 12 to 126) or 64 g/m2 (range 46 to 79); on MRI it was 60 g (range 33 to 87) or 69 g/m2 (range 46 to 89). Regression analysis yielded an r value of 0.98 with a standard error of the estimate of 5.7 g or a 10% difference. In older children, LV mass determined by MRI was bigger than the one derived by echocardiography. It is concluded that cross-sectional echocardiography can reliably assess LV myocardial mass in pediatric patients.

Cardiac magnetic resonance analysis of right ventricular function: comparison of quantification in the short-axis and 4-chamber planes.

PubMed

Souto Bayarri, M; Masip Capdevila, L; Remuiñan Pereira, C; Suárez-Cuenca, J J; Martínez Monzonís, A; Couto Pérez, M I; Carreira Villamor, J M

2015-01-01

To compare the methods of right ventricle segmentation in the short-axis and 4-chamber planes in cardiac magnetic resonance imaging and to correlate the findings with those of the tricuspid annular plane systolic excursion (TAPSE) method in echocardiography. We used a 1.5T MRI scanner to study 26 patients with diverse cardiovascular diseases. In all MRI studies, we obtained cine-mode images from the base to the apex in both the short-axis and 4-chamber planes using steady-state free precession sequences and 6mm thick slices. In all patients, we quantified the end-diastolic volume, end-systolic volume, and the ejection fraction of the right ventricle. On the same day as the cardiac magnetic resonance imaging study, 14 patients also underwent echocardiography with TAPSE calculation of right ventricular function. No statistically significant differences were found in the volumes and function of the right ventricle calculated using the 2 segmentation methods. The correlation between the volume estimations by the two segmentation methods was excellent (r=0,95); the correlation for the ejection fraction was slightly lower (r=0,8). The correlation between the cardiac magnetic resonance imaging estimate of right ventricular ejection fraction and TAPSE was very low (r=0,2, P<.01). Both ventricular segmentation methods quantify right ventricular function adequately. The correlation with the echocardiographic method is low. Copyright © 2012 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Accurate computer-aided quantification of left ventricular parameters: experience in 1555 cardiac magnetic resonance studies from the Framingham Heart Study.

PubMed

Hautvast, Gilion L T F; Salton, Carol J; Chuang, Michael L; Breeuwer, Marcel; O'Donnell, Christopher J; Manning, Warren J

2012-05-01

Quantitative analysis of short-axis functional cardiac magnetic resonance images can be performed using automatic contour detection methods. The resulting myocardial contours must be reviewed and possibly corrected, which can be time-consuming, particularly when performed across all cardiac phases. We quantified the impact of manual contour corrections on both analysis time and quantitative measurements obtained from left ventricular short-axis cine images acquired from 1555 participants of the Framingham Heart Study Offspring cohort using computer-aided contour detection methods. The total analysis time for a single case was 7.6 ± 1.7 min for an average of 221 ± 36 myocardial contours per participant. This included 4.8 ± 1.6 min for manual contour correction of 2% of all automatically detected endocardial contours and 8% of all automatically detected epicardial contours. However, the impact of these corrections on global left ventricular parameters was limited, introducing differences of 0.4 ± 4.1 mL for end-diastolic volume, -0.3 ± 2.9 mL for end-systolic volume, 0.7 ± 3.1 mL for stroke volume, and 0.3 ± 1.8% for ejection fraction. We conclude that left ventricular functional parameters can be obtained under 5 min from short-axis functional cardiac magnetic resonance images using automatic contour detection methods. Manual correction more than doubles analysis time, with minimal impact on left ventricular volumes and ejection fraction. Copyright © 2011 Wiley Periodicals, Inc.

The effect of enalapril and verapamil on the left ventricular hypertrophy and the left ventricular cardiomyocyte numerical density in rats submitted to nitric oxide inhibition

PubMed Central

Pereira, Leila Maria Meirelles; Mandarim-de-Lacerda, Carlos Alberto

2001-01-01

Forty male Wistar rats were separated into four groups of ten rats each (control and other three groups that have received nitric oxide (NO) synthesis inhibitor L-NAME) but the last two groups have concomitantly received antihypertensive drugs (Enalapril and Verapamil). After 40 days of experimentation, the heart and the ventricles were measured. The optical disector was used for the calculation of numerical density of the cardiomyocytes (Nv[c]). The left ventricular myocytes number (N[c]) was calculated as the product of Nv[c] and the left ventricular myocardium volume (LVMV) that was determined by using the Scherle's method. In the L-NAME group the blood pressure (BP) had a significant weekly increment. In the enalapril and the verapamil groups, BP increased in the first two weeks, but decreased in the following weeks. The LVMV increased in the L-NAME rats and decreased in the enalapril and verapamil animals. The Nv[c] and N[c] decreased in the L-NAME rats but the verapamil and enalapril treatments maintained the Nv[c] close to the control group. In conclusion, the left ventricular hypertrophy and the significant decrease of the left ventricular cardiomyocyte number caused by the NO synthesis inhibition are efficiently prevented with the use of enalapril and verapamil. PMID:11454102

Magnetic Resonance Characterization of Cardiac Adaptation and Myocardial Fibrosis in Pulmonary Hypertension Secondary to Systemic-To-Pulmonary Shunt.

PubMed

Pereda, Daniel; García-Lunar, Inés; Sierra, Federico; Sánchez-Quintana, Damián; Santiago, Evelyn; Ballesteros, Constanza; Encalada, Juan F; Sánchez-González, Javier; Fuster, Valentín; Ibáñez, Borja; García-Álvarez, Ana

2016-09-01

Pulmonary hypertension (PH) and right ventricular (RV) dysfunction are strong predictors of morbidity and mortality among patients with congenital heart disease. Early detection of RV involvement may be useful in the management of these patients. We aimed to assess progressive cardiac adaptation and quantify myocardial extracellular volume in an experimental porcine model of PH because of aorto-pulmonary shunt using cardiac magnetic resonance (CMR). To characterize serial cardiac adaptation, 12 pigs (aorto-pulmonary shunt [n=6] or sham operation [n=6]) were evaluated monthly with right heart catheterization, CMR, and computed tomography during 4 months, followed by pathology analysis. Extracellular volume by CMR in different myocardial regions was studied in 20 animals (aorto-pulmonary shunt [n=10] or sham operation [n=10]) 3 months after the intervention. All shunted animals developed PH. CMR evidenced progressive RV hypertrophy and dysfunction secondary to increased afterload and left ventricular dilatation secondary to volume overload. Shunt flow by CMR strongly correlated with PH severity, left ventricular end-diastolic pressure, and left ventricular dilatation. T1-mapping sequences demonstrated increased extracellular volume at the RV insertion points, the interventricular septum, and the left ventricular lateral wall, reproducing the pattern of fibrosis found on pathology. Extracellular volume at the RV insertion points strongly correlated with pulmonary hemodynamics and RV dysfunction. Prolonged systemic-to-pulmonary shunting in growing piglets induces PH with biventricular remodeling and myocardial fibrosis that can be detected and monitored using CMR. These results may be useful for the diagnosis and management of congenital heart disease patients with pulmonary overcirculation. © 2016 American Heart Association, Inc.

Echocardiographic chamber quantification in a healthy Dutch population.

PubMed

van Grootel, R W J; Menting, M E; McGhie, J; Roos-Hesselink, J W; van den Bosch, A E

2017-12-01

For accurate interpretation of echocardiographic measurements normative data are required, which are provided by guidelines. For this article, the hypothesis was that these cannot be extrapolated to the Dutch population, since in Dutch clinical practice often higher values are found, which may not be pathological but physiological. Therefore this study aimed to 1) obtain and propose normative values for cardiac chamber quantification in a healthy Dutch population and 2) determine influences of baseline characteristics on these measurements. Prospectively recruited healthy subjects, aged 20-72 years (at least 28 subjects per age decade, equally distributed for gender) underwent physical examination and 2D and 3D echocardiography. Both ventricles and atria were assessed and volumes were calculated. 147 subjects were included (age 44 ± 14 years, 50% female). Overall, feasibility was good for both linear and volumetric measurements. Linear and volumetric parameters were consistently higher than current guidelines recommend, while functional parameters were in line with the guidelines. This was more so in the older population. 3D volumes were higher than 2D volumes. Gender dependency was seen in all body surface area (BSA) corrected volumes and with increasing age, ejection fractions decreased. This study provides 2D and 3D echocardiographic reference ranges for both ventricles and atria derived from a healthy Dutch population. BSA indexed volumes are gender-dependent, age did not influence ventricular volumes and a rise in blood pressure was independently associated with increased right ventricular volumes. The higher volumes found may be indicative for the Dutch population being the tallest in the world.

Effect of hydration status on atrial and ventricular volumes and function in healthy adult volunteers.

PubMed

Schantz, Daryl I; Dragulescu, Andreea; Memauri, Brett; Grotenhuis, Heynric B; Seed, Mike; Grosse-Wortmann, Lars

2016-10-01

Assessment of cardiac chamber volumes is a fundamental part of cardiac magnetic resonance (CMR) imaging. While the effects of inter- and intraobserver variability have been studied and have a recognized effect on the comparability of serial cardiac MR imaging studies, the effect of differences in hydration status has not been evaluated. To evaluate the effects of volume administration on cardiac chamber volumes. Thirteen healthy adults underwent a baseline cardiac MR to evaluate cardiac chamber volumes after an overnight fast. They were then given two saline boluses of 10 ml/kg of body weight and the cardiac MR was repeated immediately after each bolus. From the baseline scan to the final scan there was a significant increase in all four cardiac chamber end-diastolic volumes. Right atrial volumes increased 8.0%, from 61.1 to 66.0 ml/m2 (P<0.001), and left atrial volumes increased 10.0%, from 50.0 to 55.0 ml/m2 (P<0.001). Right ventricular volumes increased 6.0%, from 91.1 to 96.5 ml/m2 (P<0.001), and left ventricular volumes increased 3.2%, from 87.0 to 89.8 ml/m2 (P<0.001). Hydration status has a significant effect on the end-diastolic volumes of all cardiac chambers assessed by cardiac MR. Thus, hydration represents a "variable" that should be taken into account when assessing cardiac chamber volumes, especially when performing serial imaging studies in a patient.

Impact of the right ventricular lead position on clinical outcome and on the incidence of ventricular tachyarrhythmias in patients with CRT-D.

PubMed

Kutyifa, Valentina; Bloch Thomsen, Poul Erik; Huang, David T; Rosero, Spencer; Tompkins, Christine; Jons, Christian; McNitt, Scott; Polonsky, Bronislava; Shah, Amil; Merkely, Bela; Solomon, Scott D; Moss, Arthur J; Zareba, Wojciech; Klein, Helmut U

2013-12-01

Data on the impact of right ventricular (RV) lead location on clinical outcome and ventricular tachyarrhythmias in cardiac resynchronization therapy with defibrillator (CRT-D) patients are limited. To evaluate the impact of different RV lead locations on clinical outcome in CRT-D patients enrolled in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy trial. We investigated 742 of 1089 CRT-D patients (68%) with adjudicated RV lead location enrolled in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy trial to evaluate the impact of RV lead location on cardiac events. The primary end point was heart failure or death; secondary end points included ventricular tachycardia (VT), ventricular fibrillation (VF), or death and VT or VF alone. Eighty-six patients had the RV lead positioned at the RV septal or right ventricular outflow tract region, combined as nonapical RV group, and 656 patients had apical RV lead location. There was no difference in the primary end point in patients with nonapical RV lead location versus those with apical RV lead location (hazard ratio [HR] 0.98; 95% confidence interval [CI] 0.54-1.80; P = .983). Echocardiographic response to CRT-D was comparable across RV lead location groups (P > .05 for left ventricular end-diastolic volume, left ventricular end-systolic volume, and left atrial volume percent change). However, nonapical RV lead location was associated with significantly higher risk of VT/VF/death (HR 2.45; 95% CI 1.36-4.41; P = .003) and VT/VF alone (HR 2.52; 95% CI 1.36-4.65; P = .002), predominantly in the first year after device implantation. Results were consistent in patients with left bundle branch block. In CRT-D patients, there is no benefit of nonapical RV lead location in clinical outcome or echocardiographic response. Moreover, nonapical RV lead location is associated with an increased risk of ventricular tachyarrhythmias, particularly in the first year after device implantation. Published by Elsevier Inc.

Stroke Volume During Concomitant Apnea and Exercise: Influence of Gravity and Venous Return

NASA Astrophysics Data System (ADS)

Hoffmann, Uwe; Drager, Tobias; Steegmanns, Ansgar; Koesterer, Thomas; Linnarsson, Dag

2008-06-01

The responses of the cardiovascular system to intensive exercise (hiP) and combined stimuli by hiP and breath-hold (hiP-BH) for 20 s were examined during changing gravity (parabolic flight) and constant gravity (1g). The basic response to microgravity (μg) during low-intensity exercise was an increase in cardiac output (CO) and stroke volume (SV) as a result of augmented venous return. When onset of hiP was superimposed, the initial augmentation of CO and SV were increased further. In contrast, when BH was added, the increases of CO and SV were slowed. We propose that this was due to a transient increase of the pulmonary blood volume with the combination of μg and BH at large lung volume, creating a temporary imbalance between right ventricular input and left ventricular output. In addition, the BH- induced relative bradycardia may have contributed to a prolongation of the right-to- left indirect ventricular interdependence.

Rationale and design of the Multidisciplinary Approach to Novel Therapies in Cardiology Oncology Research Trial (MANTICORE 101--Breast): a randomized, placebo-controlled trial to determine if conventional heart failure pharmacotherapy can prevent trastuzumab-mediated left ventricular remodeling among patients with HER2+ early breast cancer using cardiac MRI.

PubMed

Pituskin, Edith; Haykowsky, Mark; Mackey, John R; Thompson, Richard B; Ezekowitz, Justin; Koshman, Sheri; Oudit, Gavin; Chow, Kelvin; Pagano, Joseph J; Paterson, Ian

2011-07-27

MANTICORE 101 - Breast (Multidisciplinary Approach to Novel Therapies in Cardiology Oncology Research) is a randomized trial to determine if conventional heart failure pharmacotherapy (angiotensin converting enzyme inhibitor or beta-blocker) can prevent trastuzumab-mediated left ventricular remodeling, measured with cardiac MRI, among patients with HER2+ early breast cancer. One hundred and fifty-nine patients with histologically confirmed HER2+ breast cancer will be enrolled in a parallel 3-arm, randomized, placebo controlled, double-blind design. After baseline assessments, participants will be randomized in a 1:1:1 ratio to an angiotensin-converting enzyme inhibitor (perindopril), beta-blocker (bisoprolol), or placebo. Participants will receive drug or placebo for 1 year beginning 7 days before trastuzumab therapy. Dosages for all groups will be systematically up-titrated, as tolerated, at 1 week intervals for a total of 3 weeks. The primary objective of this randomized clinical trial is to determine if conventional heart failure pharmacotherapy can prevent trastuzumab-mediated left ventricular remodeling among patients with HER2+ early breast cancer, as measured by 12 month change in left ventricular end-diastolic volume using cardiac MRI. Secondary objectives include 1) determine the evolution of left ventricular remodeling on cardiac MRI in patients with HER2+ early breast cancer, 2) understand the mechanism of trastuzumab mediated cardiac toxicity by assessing for the presence of myocardial injury and apoptosis on serum biomarkers and cardiac MRI, and 3) correlate cardiac biomarkers of myocyte injury and extra-cellular matrix remodeling with left ventricular remodeling on cardiac MRI in patients with HER2+ early breast cancer. Cardiac toxicity as a result of cancer therapies is now recognized as a significant health problem of increasing prevalence. To our knowledge, MANTICORE will be the first randomized trial testing proven heart failure pharmacotherapy in the prevention of trastuzumab-mediated cardiotoxicity. We expect the findings of this trial to provide important evidence in the development of guidelines for preventive therapy. ClinicalTrials.gov: NCT01016886.

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.

Cardiac chamber volumes by echocardiography using a new mathematical method: A promising technique for zero-G use

NASA Technical Reports Server (NTRS)

Buckey, J. C.; Beattie, J. M.; Gaffney, F. A.; Nixon, J. V.; Blomqvist, C. G.

1984-01-01

Accurate, reproducible, and non-invasive means for ventricular volume determination are needed for evaluating cardiovascular function zero-gravity. Current echocardiographic methods, particularly for the right ventricle, suffer from a large standard error. A new mathematical approach, recently described by Watanabe et al., was tested on 1 normal formalin-fixed human hearts suspended in a mineral oil bath. Volumes are estimated from multiple two-dimensional echocardiographic views recorded from a single point at sequential angles. The product of sectional cavity area and center of mass for each view summed over the range of angles (using a trapezoidal rule) gives volume. Multiple (8-14) short axis right ventricle and left ventricle views at 5.0 deg intervals were videotaped. The images were digitized by two independent observers (leading-edge to leading-edge technique) and analyzed using a graphics tablet and microcomputer. Actual volumes were determined by filling the chambers with water. These data were compared to the mean of the two echo measurements.

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.

Effects of 12 days exposure to simulated microgravity on central circulatory hemodynamics in the rhesus monkey

NASA Astrophysics Data System (ADS)

Convertino, V. A.; Koenig, S. C.; Krotov, V. P.; Fanton, J. W.; Korolkov, V. I.; Trambovetsky, E. V.; Ewert, D. L.; Truzhennikov, A.; Latham, R. D.

Central circulatory hemodynamic responses were measured before and during the initial 9 days of a 12-day 10 ° head-down tilt (HDT) in 4 flight-sized juvenile rhesus monkeys who were surgically instrumented with a variety of intrathoracic catheters and blood flow sensors to assess the effects of simulated microgravity on central circulatory hemodynamics. Each subject underwent measurements of aortic and left ventricular pressures, and aortic flow before and during HDT as well as during a passive head-up postural test before and after HDT. Heart rate, stroke volume, cardiac output, and left ventricular end-diastolic pressure were measured, and dP/dt and left ventricular elastance was calculated from hemodynamic measurements. The postural test consisted of 5 min of supine baseline control followed by 5 minutes of 90 ° upright tilt (HUT). Heart rate, stroke volume, cardiac output, and left ventricular end-diastolic pressure showed no consistent alterations during HDT. Left ventricular elastance was reduced in all animals throughout HDT, indicating that cardiac compliance was increased. HDT did not consistently alter left ventricular +dP/dt, indicating no change in cardiac contractility. Heart rate during the post-HDT HUT postural test was elevated compared to pre-HDT while post-HDT cardiac output was decreased by 52% as a result of a 54% reduction in stroke volume throughout HUT. Results from this study using an instrumented rhesus monkey suggest that exposure to microgravity may increase ventricular compliance without alterating cardiac contractility. Our project supported the notion that an invasively-instrumented animal model should be viable for use in spaceflight cardiovascular experiments to assess potential changes in myocardial function and cardiac compliance.

Effects of 12 days exposure to simulated microgravity on central circulatory hemodynamics in the rhesus monkey

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Koenig, S. C.; Krotov, V. P.; Fanton, J. W.; Korolkov, V. I.; Trambovetsky, E. V.; Ewert, D. L.; Truzhennikov, A.; Latham, R. D.

1998-01-01

Central circulatory hemodynamic responses were measured before and during the initial 9 days of a 12-day 10 degrees head-down tilt (HDT) in 4 flight-sized juvenile rhesus monkeys who were surgically instrumented with a variety of intrathoracic catheters and blood flow sensors to assess the effects of simulated microgravity on central circulatory hemodynamics. Each subject underwent measurements of aortic and left ventricular pressures, and aortic flow before and during HDT as well as during a passive head-up postural test before and after HDT. Heart rate, stroke volume, cardiac output, and left ventricular end-diastolic pressure were measured, and dP/dt and left ventricular elastance was calculated from hemodynamic measurements. The postural test consisted of 5 min of supine baseline control followed by 5 minutes of 90 degrees upright tilt (HUT). Heart rate, stroke volume, cardiac output, and left ventricular end-diastolic pressure showed no consistent alterations during HDT. Left ventricular elastance was reduced in all animals throughout HDT, indicating that cardiac compliance was increased. HDT did not consistently alter left ventricular +dP/dt, indicating no change in cardiac contractility. Heart rate during the post-HDT HUT postural test was elevated compared to pre-HDT while post-HDT cardiac output was decreased by 52% as a result of a 54% reduction in stroke volume throughout HUT. Results from this study using an instrumented rhesus monkey suggest that exposure to microgravity may increase ventricular compliance without alternating cardiac contractility. Our project supported the notion that an invasively-instrumented animal model should be viable for use in spaceflight cardiovascular experiments to assess potential changes in myocardial function and cardiac compliance.

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

Kropp, J.; Reske, S.N.; Biersack, H.J.

Stimulated Renin-Angiotensin System (RAS) in aortic insufficiency (AI) leads to increased afterload and consequently to augmented aortic regurgitation (R). Therefore Captopril (C) mediated RAS-inhibition should diminish systemic vascular resistance and thus reduce R. In 9 patients (pts) with pure severe AI regurgitation fraction (RF) and left ventricular ejection fraction (LVEF) were determined before and 1 hr after i.v. injection of 25 mg C by gated radionuclide ventriculographie (RNV), using red blood cells labeled in vivo with 15 mCi Tc-99m. Enddiastolic and endsystolid frames were derived from the left ventricular volume curve. ROI's were selected over both ventricles. Ventricular boundaries weremore » defined by a fourier phase image overlay. RF was calculated by the background corrected count rate ratio of left and right ventricular ROI. Arterial blood pressure (BP), heart rate (HR), plasma levels of angiotensin I, II (A1,A2), and the activity of angiotensin converting enzyme (ACE) were determined before and 1 hr after C-injection. Before C-medication mean RF was 54% (range 34% - 67%), after C mean RF decreased to 37% (17% - 59% range, rho<.05). Mean LVEF increased not significantly from 60% (range 51%-70%) to 66% (range 56% - 77%, rho>0.55). C did not significantly change HR or BP (HR: rho>0.9, BP: rho>0.6). A2 and ACE activity decreased to 40% and 50% of control values (rho<.01), respectively. A1 increased excessively. The authors conclude that the inhibition of ACE reduces significantly aortic regurgitation in patients with A1 and has thus a beneficial effect on left ventricular performance.« less

Left atrial volume index in patients with heart failure and severely impaired left ventricular systolic function: the role of established echocardiographic parameters, circulating cystatin C and galectin-3.

PubMed

Zivlas, Christos; Triposkiadis, Filippos; Psarras, Stelios; Giamouzis, Gregory; Skoularigis, Ioannis; Chryssanthopoulos, Stavros; Kapelouzou, Alkistis; Ramcharitar, Steve; Barnes, Edward; Papasteriadis, Evangelos; Cokkinos, Dennis

2017-11-01

Backround: Left atrial (LA) enlargement plays an important role in the development of heart failure (HF) and is a robust prognostic factor. Fibrotic processes have also been advocated to evoke HF through finite signalling proteins. We examined the association of two such proteins, cystatin C (CysC) and galectin-3 (Gal-3), and other clinical, echocardiographic and biochemical parameters with LA volume index (LAVi) in patients with HF with severely impaired left ventricular ejection fraction (LVEF). Severe renal, liver, autoimmune disease and cancer were exclusion criteria. A total of 40 patients with HF (31 men, age 66.6 ± 1.7) with LVEF = 25.4 ± 0.9% were divided into two groups according to the mean LAVi (51.03 ± 2.9 ml/m 2 ) calculated by two-dimensional transthoracic echocardiography. Greater LAVi was positively associated with LV end-diastolic volume ( p = 0.017), LV end-systolic volume ( p = 0.025), mitral regurgitant volume (MRV) ( p = 0.001), right ventricular systolic pressure (RVSP) ( p < 0.001), restrictive diastolic filling pattern ( p = 0.003) and atrial fibrillation ( p = 0.005). Plasma CysC was positively correlated with LAVi ( R 2 = 0.135, p = 0.019) and log-transformed plasma Gal-3 ( R 2 = 0.109, p = 0.042) by simple linear regression analysis. Stepwise multiple linear regression analysis showed that only MRV ( t = 2.236, p = 0.032), CysC ( t = 2.467, p = 0.019) and RVSP ( t = 2.155, p = 0.038) were significant predictors of LAVi. Apart from known determinants of LAVi, circulating CysC and Gal-3 were associated with greater LA dilatation in patients with HF with reduced LVEF. Interestingly, the correlation between these two fibrotic proteins was positive.

Comparison of stroke work between repaired tetralogy of Fallot and normal right ventricular physiologies.

PubMed

Lee, Namheon; Das, Ashish; Banerjee, Rupak K; Gottliebson, William M

2013-01-01

Adult patients who underwent tetralogy of Fallot repair surgery (rTOF) confront life-threatening ailments due to right ventricular (RV) myocardial dysfunction. Pulmonary valve replacement (PVR) needs to be performed to restore the deteriorating RV function. Determination of correct timing to perform PVR in an rTOF patient remains subjective, due to the unavailability of quantifiable clinical diagnostic parameters. The objective of this study is to evaluate the possibility of using RV body surface area (BSA)-indexed stroke work (SW(I)) to quantify RV inefficiency in TOF patients. We hypothesized that RV SW(I) required to push blood to the lungs in rTOF patients is significantly higher than that of normal subjects. Seven patients with rTOF pathophysiology and eight controls with normal RV physiology were registered for this study. Right ventricular volume and pressure were measured using cardiac magnetic resonance imaging and catheterization, respectively. Statistical analysis was performed to quantify the difference in SW(I) between the RV of the rTOF and control groups. Right ventricular SW(I) in rTOF patients (0.176 ± 0.055 J/m(2)) was significantly higher by 93.4% (P = 0.0026) than that of controls (0.091 ± 0.030 J/m(2)). Further, rTOF patients were found to have significantly higher (P < 0.05) BSA normalized RV end-systolic volume, end-systolic pressure, and regurgitation fraction than control subjects. Ejection fraction and peak ejection rate of rTOF patients were significantly lower (P < 0.05) than those of controls. Patients with rTOF pathophysiology had significantly higher RV SW(I) compared with subjects with normal RV physiology. Therefore, RV SW(I) may be useful to quantify RV inefficiency in rTOF patients along with currently used clinical end points such as RV volume, pressure, regurgitation fraction, and ejection fraction.

Three-Dimensional Echocardiography-Derived Non-Invasive Right Ventricular Pressure-Volume Analysis.

PubMed

Huang, Kuan-Chih; Lin, Lian-Yu; Hwang, Juey-Jen; Lin, Lung-Chun

2017-09-01

In patients with pulmonary hypertension, repeated evaluations of right ventricular (RV) function are still required for clinical decision making, but the invasive nature of current pressure-volume analysis makes conducting regular follow-ups in a clinical setting infeasible. We enrolled 12 patients with pulmonary arterial hypertension (PAH) and 10 with pulmonary venous hypertension (PVH) May 2016-October 2016. All patients underwent a clinically indicated right heart catheterization (RHC), from which the yielded right ventricular pressure recordings were conjugated with RV volume by 3-D echocardiography to generate a pressure-volume loop. A continuous-wave Doppler envelope of tricuspid regurgitation was transformed into a pressure gradient recording by the simplified Bernoulli equation, and then a systolic pressure gradient-volume (PG-V) diagram was generated from similar methods. The area enclosed by the pressure-volume loop was calculated to represent semi-invasive right ventricular stroke work (RVSW RHC ). The area between the PG-V diagram and x-axis was calculated to estimate non-invasive RVSW (RVSW echo ). Patients with PAH have higher RV pressure, lower pulmonary arterial wedge pressure and larger RV volume that was contributed by the dilation of RV mid-cavity minor dimension. We found no significant difference of traditional parameters between these two groups, but RVSW values were significantly higher in PAH patients. The RVSW values of these two methods were significantly correlated by the equation RVSW echo  = 0.8447 RVSW RHC  + 129.38 (R 2  = 0.9151, p < 0.001). The linearity remained satisfactory in both groups. We conclude that a PG-V diagram is a reliable method to estimate RVSW and to depict pathophysiological status. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Right Ventricular Volumes and Systolic Function by Cardiac Magnetic Resonance and the Impact of Sex, Age, and Obesity in a Longitudinally Followed Cohort Free of Pulmonary and Cardiovascular Disease: The Framingham Heart Study.

PubMed

Foppa, Murilo; Arora, Garima; Gona, Philimon; Ashrafi, Arman; Salton, Carol J; Yeon, Susan B; Blease, Susan J; Levy, Daniel; O'Donnell, Christopher J; Manning, Warren J; Chuang, Michael L

2016-03-01

Cardiac magnetic resonance is uniquely well suited for noninvasive imaging of the right ventricle. We sought to define normal cardiac magnetic resonance reference values and to identify the main determinants of right ventricular (RV) volumes and systolic function using a modern imaging sequence in a community-dwelling, longitudinally followed cohort free of clinical cardiovascular and pulmonary disease. The Framingham Heart Study Offspring cohort has been followed since 1971. We scanned 1794 Offspring cohort members using steady-state free precession cardiac magnetic resonance and identified a reference group of 1336 adults (64±9 years, 576 men) free of prevalent cardiovascular and pulmonary disease. RV trabeculations and papillary muscles were considered cavity volume. Men had greater RV volumes and cardiac output before and after indexation to body size (all P<0.001). Women had higher RV ejection fraction than men (68±6% versus 64±7%; P<0.0001). RV volumes and cardiac output decreased with advancing age. There was an increase in raw and height-indexed RV measurements with increasing body mass index, but this trend was weakly inverted after indexation of RV volumes to body surface area. Sex, age, height, body mass index, and heart rate account for most of the variability in RV volumes and function in this community-dwelling population. We report sex-specific normative values for RV measurements among principally middle-aged and older adults. RV ejection fraction is greater in women. RV volumes increase with body size, are greater in men, and are smaller in older people. Body surface area seems to be appropriate for indexation of cardiac magnetic resonance-derived RV volumes. © 2016 American Heart Association, Inc.

Biplane roentgen videometric system for dynamic, 60/sec, studies of the shape and size of circulatory structures, particularly the left ventricle.

NASA Technical Reports Server (NTRS)

Ritman, E. L.; Sturm, R. E.; Wood, E. H.

1973-01-01

An operator interactive video system for the measurement of roentgen angiographically outlined structures is described. Left ventricular volume and three-dimensional shapes are calculated from up to 200 pairs of diameters measured from ventriculograms at the rate of 60 pairs of biplane images per second. The accuracy and reproducibility of volumes calculated by the system were established by analysis of roentgenograms of inanimate objects of known volume and by comparison of left ventricular stroke volumes calculated by the system with the stroke volumes calculated by an indicator-dilution technique and an aortic root electromagnetic flowmeter. Computer-generated display of the large amounts of data obtained by the videometry system is described.

Left ventricular mass in elite olympic weight lifters.

PubMed

Lalande, Sophie; Baldi, James Christopher

2007-10-01

The existence of resistance training-induced left ventricular (LV) concentric hypertrophy is equivocal. Although some have described significant LV hypertrophy, others have suggested that training-induced LV hypertrophy is proportional to increased fat free mass (FFM) and thus a normal physiologic response to training. Method limitations, steroid use, and type of training may contribute to discrepant findings. Thus, LV structure and volumes are determined using magnetic resonance imaging. Body composition was determined using dual-energy x-ray absorptiometry in 9 elite Olympic weight lifters and 10 age- and weight-matched recreationally active controls. LV structure and volumes were determined by acquiring 6 short- and 3 long-axis magnetic resonance imaging scans of the left ventricle, whereas LV wall thickness was defined as the average of 6 midventricular segment thickness measurements. Weight lifters had the same age, weight, and FFM, but were shorter and had a greater body mass index than controls. LV mass was not different in weight lifters and controls, but was lower in weight lifters when indexed to FFM (2.56 +/- 0.07 vs 2.30 +/- 0.05, p = 0.01). LV mass correlated with FFM (r = 0.49, p = 0.04). However, LV mass was lower in weight lifters for a given FFM. LV wall thickness, as well as end-diastolic, end-systolic, and stroke volumes, were not different between groups. In conclusion, these results refute the hypothesis that resistance training induces LV concentric hypertrophy and suggest that Olympic weight lifting is associated with increases in FFM without a concomitant increase in LV mass.

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

Sleep Apnea and Left Atrial Phasic Function in Heart Failure With Reduced Ejection Fraction.

PubMed

Haruki, Nobuhiko; Tsang, Wendy; Thavendiranathan, Paaladinesh; Woo, Anna; Tomlinson, George; Logan, Alexander G; Bradley, T Douglas; Floras, John S

2016-12-01

The study aim was to determine whether phasic left atrial (LA) function of patients with heart failure with reduced ejection fraction differs between those with obstructive sleep apnea (OSA) and central sleep apnea (CSA). Participation in the Adaptive Servo Ventilation for Therapy of Sleep Apnea in Heart Failure (ADVENT-HF) trial requires 2-dimensional echocardiographic documentation of left ventricular ejection fraction ≤ 45% and a polysomnographic apnea hypopnea index (AHI) ≥ 15 events per hour. Of initial enrollees, we identified 132 patients in sinus rhythm (82 with predominantly OSA and 50 with CSA). To determine LA reservoir (expansion index; EI), conduit (passive emptying index; PEI), and booster function (active emptying index), we blindly quantified maximum and minimum LA volume and LA volume before atrial contraction. Each of EI (P = 0.004), PEI (P < 0.001), and active emptying index (P = 0.045) was less in participants with CSA compared with those with OSA, whereas average left ventricular ejection fraction and LA and left ventricular volumes were similar. Multivariable analysis identified an independent relationship between central AHI and LA EI (P = 0.040) and PEI (P = 0.005). In contrast, the obstructive AHI was unrelated to any LA phasic index, and slopes relating central AHI to EI and PEI differed significantly from corresponding relationships with obstructive AHI (P = 0.018; P = 0.006). In these ADVENT-HF patients with heart failure with reduced ejection fraction, all 3 components of LA phasic function (reservoir, conduit, and contractile) were significantly reduced in those with CSA compared with participants with OSA. The severity of CSA, but not OSA associated inversely and independently with LA reservoir and conduit function. Impaired LA phasic function might be consequent to or could exacerbate CSA. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Dynamic characteristic mechanism of atrial septal defect using real-time three-dimensional echocardiography and evaluation of right ventricular functions.

PubMed

Sharen, Gao-Wa; Zhang, Jun; Qin, Chuan; Lv, Qing

2017-02-01

The dynamic characteristics of the area of the atrial septal defect (ASD) were evaluated using the technique of real-time three-dimensional echocardiography (RT 3DE), the potential factors responsible for the dynamic characteristics of the area of ASD were observed, and the overall and local volume and functions of the patients with ASD were measured. RT 3DE was performed on the 27 normal controls and 28 patients with ASD. Based on the three-dimensional data workstations, the area of ASD was measured at P wave vertex, R wave vertex, T wave starting point, and T wave terminal point and in the T-P section. The right atrial volume in the same time phase of the cardiac cycle and the motion displacement distance of the tricuspid annulus in the corresponding period were measured. The measured value of the area of ASD was analyzed. The changes in the right atrial volume and the motion displacement distance of the tricuspid annulus in the normal control group and the ASD group were compared. The right ventricular ejection fractions in the normal control group and the ASD group were compared using the RT 3DE long-axis eight-plane (LA 8-plane) method. Real-time three-dimensional volume imaging was performed in the normal control group and ASD group (n=30). The right ventricular inflow tract, outflow tract, cardiac apex muscular trabecula dilatation, end-systolic volume, overall dilatation, end-systolic volume, and appropriate local and overall ejection fractions in both two groups were measured with the four-dimensional right ventricular quantitative analysis method (4D RVQ) and compared. The overall right ventricular volume and the ejection fraction measured by the LA 8-plane method and 4D RVQ were subjected to a related analysis. Dynamic changes occurred to the area of ASD in the cardiac cycle. The rules for dynamic changes in the area of ASD and the rules for changes in the right atrial volume in the cardiac cycle were consistent. The maximum value of the changes in the right atrial volume occurred in the end-systolic period when the peak of the curve appeared. The minimum value of the changes occurred in the end-systolic period and was located at the lowest point of the volume variation curve. The area variation curve for ASD and the motion variation curve for the tricuspid annulus in the cardiac cycle were the same. The displacement of the tricuspid annulus exhibited directionality. The measured values of the area of ASD at P wave vertex, R wave vertex, T wave starting point, T wave terminal point and in the T-P section were properly correlated with the right atrial volume (P<0.001). The area of ASD and the motion displacement distance of the tricuspid annulus were negatively correlated (P<0.05). The right atrial volumes in the ASD group in the cardiac cycle in various time phases increased significantly as compared with those in the normal control group (P=0.0001). The motion displacement distance of the tricuspid annulus decreased significantly in the ASD group as compared with that in the normal control group (P=0.043). The right ventricular ejection fraction in the ASD group was lower than that in the normal control group (P=0.032). The ejection fraction of the cardiac apex trabecula of the ASD patients was significantly lower than the ejection fractions of the right ventricular outflow tract and inflow tract and overall ejection fraction. The difference was statistically significant (P=0.005). The right ventricular local and overall dilatation and end-systolic volumes in the ASD group increased significantly as compared with those in the normal control group (P=0.031). The aRVEF and the overall ejection fraction decreased in the ASD group as compared with those in the normal control group (P=0.0005). The dynamic changes in the area of ASD and the motion curves for the right atrial volume and tricuspid annulus have the same dynamic characteristics. RT 3DE can be used to accurately evaluate the local and overall volume and functions of the right ventricle. The local and overall volume loads of the right ventricle in the ASD patients increase significantly as compared with those of the normal people. The right ventricular cardiac apex and the overall systolic function decrease.

Sustained Improvement in Right Ventricular Chamber Dimensions 10 Years Following Xenograft Pulmonary Valve Replacement.

PubMed

Schubmehl, Heidi B; Swartz, Michael F; Atallah-Yunes, Nader; Wittlieb-Weber, Carol; Pratt, Rebecca E; Alfieris, George M

2017-01-01

The goals following pulmonary valve replacement (PVR) are to optimize right ventricular hemodynamics and minimize the need for subsequent reoperations on the right ventricular outflow tract. We hypothesized PVR using a xenograft valved conduit would result in superior freedom from reoperation with sustained improvement in right ventricular chamber dimensions. Xenograft valved conduits placed in patients aged >16 years were reviewed from 2000 to 2010 to allow for a 5-year minimum follow-up. Preoperative, one-year, and the most recent echocardiograms quantified right ventricular chamber dimensions, corresponding Z scores, and prosthetic valve function. Magnetic resonance imaging (MRI) studies compared preoperative and follow-up right ventricular volumes. A total of 100 patients underwent PVR at 24 (19-34) years. Freedom from reintervention was 100% at 10 years. At most recent follow-up, only one patient had greater than mild pulmonary insufficiency. The one-year (17.3 ± 7.2 mm Hg; P < .01) and most recent follow-up (18.6 ± 9.8 mm Hg; P < .01) Doppler-derived right ventricular outflow tract gradients remained significantly lower than preoperative measurements (36.7 ± 27.0 mm Hg). Similarly, right ventricular basal diameter, basal longitudinal diameter, and the corresponding Z scores remained lower at one year and follow-up from preoperative measurements. From 34 MRI studies, the right ventricular end-diastolic indexed volume (161.7 ± 58.5 vs 102.9 ± 38.3; P < .01) and pulmonary regurgitant fraction (38.0% ± 15.9% vs 0.8% ± 3.3%; P < .01) were significantly lower at 7.1 ± 3.4 years compared to the preoperative levels. Use of a xenograft valved conduit for PVR results in excellent freedom from reoperation with sustained improvement in right ventricular dimensions at an intermediate-term follow-up.

QRS Width as a Predictor of Right Ventricular Remodeling After Percutaneous Pulmonary Valve Implantation.

PubMed

Paech, C; Dähnert, I; Riede, F T; Wagner, R; Kister, T; Nieschke, K; Wagner, F; Gebauer, R A

2017-08-01

Recent data showed a right ventricular dyssynchrony in patients with tetralogy of Fallot (TOF). Percutaneous pulmonary valve implantation (PPVI) has become an important procedure to treat a pulmonary stenosis and/or regurgitation of the right ventricular outflow tract in these patients. Despite providing good results, there is still a considerable number of nonresponders to PPVI. The authors speculated that electrical dysfunction of the right ventricle plays an underestimated role in the outcome of patients after PPVI. This study aimed to investigate the influence of right ventricular electrical dysfunction, i.e., right bundle branch block (RBBB) on the RV remodeling after PPVI. The study included consecutive patients after correction of TOF with or without RBBB, who had received a PPVI previously at the Heart Center of the University of Leipzig, Germany during the period from 2012 to 2015. 24 patients were included. Patients without RBBB, i.e., with narrow QRS complexes pre-intervention, had significantly better RV function and had smaller right ventricular volumes. Patients with pre-interventionally QRS width below 150 ms showed a post-interventional remodeling of the right ventricle with the decreasing RV volumes (p = 0.001). The parameters of LV function and volume as well as RV ejection fraction remained unaffected by RBBB. The presented data indicate that the QRS width seems to be a valuable parameter in the prediction of right ventricular remodeling after PPVI, as it represents both electrical and mechanical functions of the right ventricle and may serve as an additional parameter for optimal timing of a PPVI.

EVALUATION OF RIGHT AND LEFT VENTRICULAR DIASTOLIC FILLING

PubMed Central

Pasipoularides, Ares

2013-01-01

A conceptual fluid-dynamics framework for diastolic filling is developed. The convective deceleration load (CDL) is identified as an important determinant of ventricular inflow during the E-wave (A-wave) upstroke. Convective deceleration occurs as blood moves from the inflow anulus through larger-area cross-sections toward the expanding walls. Chamber dilatation underlies previously unrecognized alterations in intraventricular flow dynamics. The larger the chamber, the larger become the endocardial surface and the CDL. CDL magnitude affects strongly the attainable E-wave (A-wave) peak. This underlies the concept of diastolic ventriculoannular disproportion. Large vortices, whose strength decreases with chamber dilatation, ensue after the E-wave peak and impound inflow kinetic energy, averting an inflow-impeding, convective Bernoulli pressure-rise. This reduces the CDL by a variable extent depending on vortical intensity. Accordingly, the filling vortex facilitates filling to varying degrees, depending on chamber volume. The new framework provides stimulus for functional genomics research, aimed at new insights into ventricular remodeling. PMID:23585308

Left Ventricular Diastolic and Systolic Material Property Estimation from Image Data

PubMed Central

Krishnamurthy, Adarsh; Villongco, Christopher; Beck, Amanda; Omens, Jeffrey; McCulloch, Andrew

2015-01-01

Cardiovascular simulations using patient-specific geometries can help researchers understand the mechanical behavior of the heart under different loading or disease conditions. However, to replicate the regional mechanics of the heart accurately, both the nonlinear passive and active material properties must be estimated reliably. In this paper, automated methods were used to determine passive material properties while simultaneously computing the unloaded reference geometry of the ventricles for stress analysis. Two different approaches were used to model systole. In the first, a physiologically-based active contraction model [1] coupled to a hemodynamic three-element Windkessel model of the circulation was used to simulate ventricular ejection. In the second, developed active tension was directly adjusted to match ventricular volumes at end-systole while prescribing the known end-systolic pressure. These methods were tested in four normal dogs using the data provided for the LV mechanics challenge [2]. The resulting end-diastolic and end-systolic geometry from the simulation were compared with measured image data. PMID:25729778

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.

Ventricular Diastolic Function in Normal Fetuses and Fetuses with Hb Bart's Disease Assessed by Color M-Mode Propagation Velocity using Cardio-STIC-M (Spatio-Temporal Image Correlation M-Mode).

PubMed

Tongsong, T; Tongprasert, F; Srisupundit, K; Luewan, S; Traisrisilp, K

2016-10-01

Purpose: To determine whether ventricular diastolic dysfunction contributes to the pathogenesis of fetal cardiac failure due to fetal anemia using fetal Hb Bart's disease as a live model and cardio-STIC-M as a diagnostic tool. Materials and Methods: Color cardio-STIC volume datasets were acquired from fetuses at risk for Hb Bart's disease during 18 - 22 weeks of gestation and normal pregnancies and pregnancies with hydrops fetalis caused by Hb Bart's disease at 28 - 32 weeks. The volumes were analyzed off-line for velocity propagation (Vp) of the right and left ventricles to assess ventricular diastolic function using color cardio-STIC-M. Results: The Vp for the right and left ventricles was studied in fetuses at 18 - 22 weeks, including 64 normal fetuses (group 1) and 22 fetuses with Hb Bart's disease (group 2), and in fetuses at 28 - 32 weeks, including 22 normal fetuses (group 3) and 16 fetuses with Hb Bart's hydrops fetalis (group 4). The Vp of the fetuses in group 1 and group 2 was not significantly different. However, the Vp for the right and left ventricles in group 4 was significantly lower than in group 3 (19.02 vs. 9.78, p < 0.001; and 20.24 vs. 13.40, p < 0.001, respectively). The inter-observer variability had fair agreement with the intra-class correlation coefficient of 0.531 (95 % CI 0.393 - 0.646, p < 0.001). Conclusion: Hydrops fetalis secondary to fetal anemia is initially caused by hypervolemia rather than ventricular diastolic dysfunction while ventricular diastolic compromise is a late occurring consequence of persistent hypervolemia, different from the mechanism of hydropic changes caused by cardiac causes. © Georg Thieme Verlag KG Stuttgart · New York.

Comparison of cardiovascular function during the early hours of bed rest and space flight

NASA Technical Reports Server (NTRS)

Lathers, C. M.; Charles, J. B.

1994-01-01

This paper reviews the cardiovascular responses of six healthy male subjects to 6 hours in a 5 degrees head-down bed rest model of weightlessness, and compares these responses to those obtained when subjects were positioned in head-up tilts of 10 degrees, 20 degrees, and 42 degrees, simulating 1/6, 1/3, and 2/3 G, respectively. Thoracic fluid index, cardiac output, stroke volume, and peak flow were measured using impedance cardiography. Cardiac dimensions and volumes were determined from two-dimensional guided M-mode echocardiograms in the left lateral decubitus position at 0, 2, 4, and 6 hours. Cardiovascular response to a stand test were compared before and after bed rest. The impedance values were related to tilt angle for the first 2 hours of tilt; however, after 3 hours, at all four angles, values began to converge, indicating that cardiovascular homeostatic mechanisms seek a common adapted state, regardless of effective gravity level (tilt angle) up to 2/3 G. Echocardiography revealed that left ventricular end-diastolic and end-systolic volume, stroke volume, ejection fraction, heart rate, and cardiac output had returned to control values by hour 6 for all tilt angles. The lack of a significant immediate change in left ventricular end-diastolic volume, despite decrements in stroke volume (P < .05) and heart rate (not significant), indicates that multiple factors may play a role in the adaptation to simulated hypogravity. The echocardiography data indicated that no angle of tilt, whether head-down or head-up for 4 to 6 hours, mimicked exactly the changes in cardiovascular function recorded after 4 to 6 hours of space flight. Changes in left ventricular end-diastolic volume during space flight and tilt may be similar, but follow a different time course. Nevertheless, head-down tilt at 5 degrees for 6 hours mimics some (stroke volume, systolic and diastolic blood pressure, mean arterial blood pressure, and total resistance), but not all, of the changes occurring in an equivalent time of space flight. The magnitude of the change in the mean heart rate response to standing was greater after six hours of tilt at -5 degrees or 10 degrees. Thus, results from the stand test after 6 hours of bed rest at -5 degrees and 10 degrees, but not at 20 degrees or 42 degrees, are similar to those obtained after space flight.

Quantification of right ventricular volumes and function by real time three-dimensional echocardiographic longitudinal axial plane method: validation in the clinical setting.

PubMed

Endo, Yuka; Maddukuri, Prasad V; Vieira, Marcelo L C; Pandian, Natesa G; Patel, Ayan R

2006-11-01

Measurement of right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) by three-dimensional echocardiographic (3DE) short-axis disc summation method has been validated in multiple studies. However, in some patients, short-axis images are of insufficient quality for accurate tracing of the RV endocardial border. This study examined the accuracy of long-axis analysis in multiple planes (longitudinal axial plane method) for assessment of RV volumes and RVEF. 3DE images were analyzed in 40 subjects with a broad range of RV function. RV end-diastolic (RVEDV) and end-systolic volumes (RVESV) and RVEF were calculated by both short-axis disc summation method and longitudinal axial plane method. Excellent correlation was obtained between the two methods for RVEDV, RVESV, and RVEF (r = 0.99, 0.99, 0.94, respectively; P < 0.0001 for all comparisons). 3DE longitudinal-axis analysis is a promising technique for the evaluation of RV function, and may provide an alternative method of assessment in patients with suboptimal short-axis images.

Effect of fluid loading on left ventricular volume and stroke volume variability in patients with end-stage renal disease: a pilot study

PubMed Central

Kanda, Hirotsugu; Hirasaki, Yuji; Iida, Takafumi; Kanao-Kanda, Megumi; Toyama, Yuki; Kunisawa, Takayuki; Iwasaki, Hiroshi

2015-01-01

Purpose The aim of this study was to investigate fluid loading-induced changes in left ventricular end-diastolic volume (LVEDV) and stroke volume variability (SVV) in patients with end-stage renal disease (ESRD) using real-time three-dimensional transesophageal echocardiography and the Vigileo-FloTrac system. Patients and methods After obtaining ethics committee approval and informed consent, 28 patients undergoing peripheral vascular procedures were studied. Fourteen patients with ESRD on hemodialysis (HD) were assigned to the HD group and 14 patients without ESRD were assigned to the control group. Institutional standardized general anesthesia was provided in both groups. SVV was measured using the Vigileo-FloTrac system. Simultaneously, a full-volume three-dimensional transesophageal echocardiography dataset was acquired to measure LVEDV, left ventricular end-systolic volume, and left ventricular ejection fraction. Measurements were obtained before and after loading 500 mL hydroxyethyl starch over 30 minutes in both groups. Results In the control group, intravenous colloid infusion was associated with a significant decrease in SVV (13.8%±2.6% to 6.5%±2.6%, P<0.001) and a significant increase in LVEDV (83.6±23.4 mL to 96.1±28.8 mL, P<0.001). While SVV significantly decreased after infusion in the HD group (16.2%±6.0% to 6.2%±2.8%, P<0.001), there was no significant change in LVEDV. Conclusion Our preliminary data suggest that fluid responsiveness can be assessed not by LVEDV but also by SVV due to underlying cardiovascular pathophysiology in patients with ESRD. PMID:26527879

Renin-Angiotensin-Aldosterone Genotype Influences Ventricular Remodeling in Infants with Single Ventricle

PubMed Central

Mital, Seema; Chung, Wendy K.; Colan, Steven D.; Sleeper, Lynn A.; Manlhiot, Cedric; Arrington, Cammon B.; Cnota, James F.; Graham, Eric M.; Mitchell, Michael E.; Goldmuntz, Elizabeth; Li, Jennifer S.; Levine, Jami C.; Lee, Teresa M.; Margossian, Renee; Hsu, Daphne T.

2011-01-01

Background We investigated the effect of polymorphisms in the renin-angiotensin-aldosterone system (RAAS) genes on ventricular remodeling, growth, renal function and response to enalapril in infants with single ventricle. Methods and Results Single ventricle infants enrolled in a randomized trial of enalapril were genotyped for polymorphisms in 5 genes: angiotensinogen, angiotensin-converting enzyme, angiotensin II type 1 receptor, aldosterone synthase, and chymase. Alleles associated with RAAS upregulation were classified as risk alleles. Ventricular mass, volume, somatic growth, renal function using estimated glomerular filtration rate (eGFR), and response to enalapril were compared between patients with ≥2 homozygous risk genotypes (high-risk), and those with <2 homozygous risk genotypes (low-risk) at two time points - before the superior-cavopulmonary-connection (pre-SCPC) and at age 14 months. Of 230 trial subjects, 154 were genotyped: 38 were high-risk, 116 were low-risk. Ventricular mass and volume were elevated in both groups pre-SCPC. Ventricular mass and volume decreased and eGFR increased after SCPC in the low-risk (p<0.05) but not the high-risk group. These responses were independent of enalapril treatment. Weight and height z-scores were lower at baseline and height remained lower in the high-risk group at 14 months especially in those receiving enalapril (p<0.05). Conclusions RAAS-upregulation genotypes were associated with failure of reverse remodeling after SCPC surgery, less improvement in renal function, and impaired somatic growth, the latter especially in patients receiving enalapril. RAAS genotype may identify a high-risk subgroup of single ventricle patients who fail to fully benefit from volume unloading surgery. Follow-up is warranted to assess longterm impact. Clinical Trial Registration Clinical Trials.gov Identifier NCT00113087 PMID:21576655

Cardiac changes induced by immersion and breath-hold diving in humans.

PubMed

Marabotti, Claudio; Scalzini, Alessandro; Cialoni, Danilo; Passera, Mirko; L'Abbate, Antonio; Bedini, Remo

2009-01-01

To evaluate the separate cardiovascular response to body immersion and increased environmental pressure during diving, 12 healthy male subjects (mean age 35.2 +/- 6.5 yr) underwent two-dimensional Doppler echocardiography in five different conditions: out of water (basal); head-out immersion while breathing (condition A); fully immersed at the surface while breathing (condition B) and breath holding (condition C); and breath-hold diving at 5-m depth (condition D). Heart rate, left ventricular volumes, stroke volume, and cardiac output were obtained by underwater echocardiography. Early (E) and late (A) transmitral flow velocities, their ratio (E/A), and deceleration time of E (DTE) were also obtained from pulsed-wave Doppler, as left ventricular diastolic function indexes. The experimental protocol induced significant reductions in left ventricular volumes, left ventricular stroke volume (P < 0.05), cardiac output (P < 0.001), and heart rate (P < 0.05). A significant increase in E peak (P < 0.01) and E/A (P < 0.01) and a significant reduction of DTE (P < 0.01) were also observed. Changes occurring during diving (condition D) accounted for most of the changes observed in the experimental series. In particular, cardiac output at condition D was significantly lower compared with each of the other experimental conditions, E/A was significantly higher during condition D than in conditions A and C. Finally, DTE was significantly shorter at condition D than in basal and condition C. This study confirms a reduction of cardiac output in diving humans. Since most of the changes were observed during diving, the increased environmental pressure seems responsible for this hemodynamic rearrangement. Left ventricular diastolic function changes suggest a constrictive effect on the heart, possibly accounting for cardiac output reduction.

Impact of Age, Sex and Indexation Method on MR Left Ventricular Reference Values in the Framingham Heart Study Offspring Cohort

PubMed Central

Yeon, Susan B.; Salton, Carol J.; Gona, Philimon; Chuang, Michael L.; Blease, Susan J.; Han, Yuchi; Tsao, Connie W.; Danias, Peter G.; Levy, Daniel; O’Donnell, Christopher J.; Manning, Warren J.

2014-01-01

Purpose To determine normative values for left ventricular (LV) volumes, mass, concentricity and ejection fraction (EF) and investigate associations between sex, age and body size with LV parameters in community dwelling adults. Materials and Methods 1794 Framingham Heart Study Offspring cohort members underwent LV short-axis oriented, contiguous multislice ciné SSFP MR of the left ventricle; from these a healthy referent group (N=852, 61±9 years, 40% men) free of clinical cardiac disease and hypertension (SBP<140, DBP<90 mmHg, never used antihypertensive medication ≥ 30 years prior to scanning) was identified. Referent participants were stratified by sex and age group (≤55, 56-65, >65 years); LV parameters were indexed to measures of body size. Results Men have greater LV volumes and mass than women both before and after indexation to height, powers of height, and body surface area (p<0.01 all), but indexation to fat-free mass yielded greater LV volume and mass in women. In both sexes, LV volumes and mass decrease with advancing age, though indexation attenuates this association. LVEF is greater in women than men (68±5% vs. 66±5%, p<0.01) and increases with age in both sexes (p<0.05). Conclusion Among non-hypertensive adults free of cardiac disease, men have greater LV volumes and mass with sex differences generally persisting after indexation to body size. LV volumes and mass tend to decrease with greater age in both sexes. Female sex and advanced age were both associated with greater LVEF. PMID:24817313

[Left ventricular volume determination by first-pass radionuclide angiocardiography using a semi-geometric count-based method].

PubMed

Kinoshita, S; Suzuki, T; Yamashita, S; Muramatsu, T; Ide, M; Dohi, Y; Nishimura, K; Miyamae, T; Yamamoto, I

1992-01-01

A new radionuclide technique for the calculation of left ventricular (LV) volume by the first-pass (FP) method was developed and examined. Using a semi-geometric count-based method, the LV volume can be measured by the following equation: CV = CM/(L/d). V = (CT/CV) x d3 = (CT/CM) x L x d2. (V = LV volume, CV = voxel count, CM = the maximum LV count, CT = the total LV count, L = LV depth where the maximum count was obtained, and d = pixel size.) This theorem was applied to FP LV images obtained in the 30-degree right anterior oblique position. Frame-mode acquisition was performed and the LV end-diastolic maximum count and total count were obtained. The maximum LV depth was obtained as the maximum width of the LV on the FP end-diastolic image, using the assumption that the LV cross-section is circular. These values were substituted in the above equation and the LV end-diastolic volume (FP-EDV) was calculated. A routine equilibrium (EQ) study was done, and the end-diastolic maximum count and total count were obtained. The LV maximum depth was measured on the FP end-diastolic frame, as the maximum length of the LV image. Using these values, the EQ-EDV was calculated and the FP-EDV was compared to the EQ-EDV. The correlation coefficient for these two values was r = 0.96 (n = 23, p less than 0.001), and the standard error of the estimated volume was 10 ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Independent effects of both right and left ventricular function on plasma brain natriuretic peptide.

PubMed

Vogelsang, Thomas Wiis; Jensen, Ruben J; Monrad, Astrid L; Russ, Kaspar; Olesen, Uffe H; Hesse, Birger; Kjaer, Andreas

2007-09-01

Brain natriuretic peptide (BNP) is increased in heart failure; however, the relative contribution of the right and left ventricles is largely unknown. To investigate if right ventricular function has an independent influence on plasma BNP concentration. Right (RVEF), left ventricular ejection fraction (LVEF), and left ventricular end-diastolic volume index (LVEDVI) were determined in 105 consecutive patients by first-pass radionuclide ventriculography (FP-RNV) and multiple ECG-gated equilibrium radionuclide ventriculography (ERNV), respectively. BNP was analyzed by immunoassay. Mean LVEF was 0.51 (range 0.10-0.83) with 36% having a reduced LVEF (<0.50). Mean RVEF was 0.50 (range 0.26-0.78) with 43% having a reduced RVEF (<0.50). The mean LVEDVI was 92 ml/m2 with 22% above the upper normal limit (117 ml/m2). Mean BNP was 239 pg/ml range (0.63-2523). In univariate linear regression analysis LVEF, LVEDVI and RVEF all correlated significantly with log BNP (p<0.0001). In a multivariate analysis only RVEF and LVEF remained significant. The parameter estimates of the final adjusted model indicated that RVEF and LVEF influence on log BNP were of the same magnitude. BNP, which is a strong prognostic marker in heart failure, independently depends on both left and right ventricular systolic function. This might, at least in part, explain why BNP holds stronger prognostic value than LVEF alone.

Ventricular enlargement in schizophrenia related to volume reduction of the thalamus, striatum, and superior temporal cortex.

PubMed

Gaser, Christian; Nenadic, Igor; Buchsbaum, Bradley R; Hazlett, Erin A; Buchsbaum, Monte S

2004-01-01

Enlargement of the lateral ventricles is among the most frequently reported macroscopic brain structural changes in schizophrenia, although variable in extent and localization. The authors investigated whether ventricular enlargement is related to regionally specific volume loss. High-resolution magnetic resonance imaging scans from 39 patients with schizophrenia were analyzed with deformation-based morphometry, a voxel-wise whole brain morphometric technique. Significant negative correlations with the ventricle-brain ratio were found for voxels in the left and right thalamus and posterior putamen and in the left superior temporal gyrus and insula. Thalamic shrinkage, especially of medial nuclei and the adjacent striatum and insular cortex, appear to be important contributors to ventricular enlargement in schizophrenia.

Effects of hormone therapy on brain structure

PubMed Central

Tosakulwong, Nirubol; Lesnick, Timothy G.; Zuk, Samantha M.; Gunter, Jeffrey L.; Gleason, Carey E.; Wharton, Whitney; Dowling, N. Maritza; Vemuri, Prashanthi; Senjem, Matthew L.; Shuster, Lynne T.; Bailey, Kent R.; Rocca, Walter A.; Jack, Clifford R.; Asthana, Sanjay; Miller, Virginia M.

2016-01-01

Objective: To investigate the effects of hormone therapy on brain structure in a randomized, double-blinded, placebo-controlled trial in recently postmenopausal women. Methods: Participants (aged 42–56 years, within 5–36 months past menopause) in the Kronos Early Estrogen Prevention Study were randomized to (1) 0.45 mg/d oral conjugated equine estrogens (CEE), (2) 50 μg/d transdermal 17β-estradiol, or (3) placebo pills and patch for 48 months. Oral progesterone (200 mg/d) was given to active treatment groups for 12 days each month. MRI and cognitive testing were performed in a subset of participants at baseline, and at 18, 36, and 48 months of randomization (n = 95). Changes in whole brain, ventricular, and white matter hyperintensity volumes, and in global cognitive function, were measured. Results: Higher rates of ventricular expansion were observed in both the CEE and the 17β-estradiol groups compared to placebo; however, the difference was significant only in the CEE group (p = 0.01). Rates of ventricular expansion correlated with rates of decrease in brain volume (r = −0.58; p ≤ 0.001) and with rates of increase in white matter hyperintensity volume (r = 0.27; p = 0.01) after adjusting for age. The changes were not different between the CEE and 17β-estradiol groups for any of the MRI measures. The change in global cognitive function was not different across the groups. Conclusions: Ventricular volumes increased to a greater extent in recently menopausal women who received CEE compared to placebo but without changes in cognitive performance. Because the sample size was small and the follow-up limited to 4 years, the findings should be interpreted with caution and need confirmation. Classification of evidence: This study provides Class I evidence that brain ventricular volume increased to a greater extent in recently menopausal women who received oral CEE compared to placebo. PMID:27473135

Effects of hormone therapy on brain structure: A randomized controlled trial.

PubMed

Kantarci, Kejal; Tosakulwong, Nirubol; Lesnick, Timothy G; Zuk, Samantha M; Gunter, Jeffrey L; Gleason, Carey E; Wharton, Whitney; Dowling, N Maritza; Vemuri, Prashanthi; Senjem, Matthew L; Shuster, Lynne T; Bailey, Kent R; Rocca, Walter A; Jack, Clifford R; Asthana, Sanjay; Miller, Virginia M

2016-08-30

To investigate the effects of hormone therapy on brain structure in a randomized, double-blinded, placebo-controlled trial in recently postmenopausal women. Participants (aged 42-56 years, within 5-36 months past menopause) in the Kronos Early Estrogen Prevention Study were randomized to (1) 0.45 mg/d oral conjugated equine estrogens (CEE), (2) 50 μg/d transdermal 17β-estradiol, or (3) placebo pills and patch for 48 months. Oral progesterone (200 mg/d) was given to active treatment groups for 12 days each month. MRI and cognitive testing were performed in a subset of participants at baseline, and at 18, 36, and 48 months of randomization (n = 95). Changes in whole brain, ventricular, and white matter hyperintensity volumes, and in global cognitive function, were measured. Higher rates of ventricular expansion were observed in both the CEE and the 17β-estradiol groups compared to placebo; however, the difference was significant only in the CEE group (p = 0.01). Rates of ventricular expansion correlated with rates of decrease in brain volume (r = -0.58; p ≤ 0.001) and with rates of increase in white matter hyperintensity volume (r = 0.27; p = 0.01) after adjusting for age. The changes were not different between the CEE and 17β-estradiol groups for any of the MRI measures. The change in global cognitive function was not different across the groups. Ventricular volumes increased to a greater extent in recently menopausal women who received CEE compared to placebo but without changes in cognitive performance. Because the sample size was small and the follow-up limited to 4 years, the findings should be interpreted with caution and need confirmation. This study provides Class I evidence that brain ventricular volume increased to a greater extent in recently menopausal women who received oral CEE compared to placebo. © 2016 American Academy of Neurology.

Emerging hemodynamic signatures of the right heart (Third International Right Heart Failure Summit, part 2).

PubMed

Maron, Bradley A

2014-12-01

Despite the importance of preserved right ventricular structure and function with respect to outcome across the spectrum of lung, cardiac, and pulmonary vascular diseases, only recently have organized efforts developed to consider the pulmonary vascular-right ventricular apparatus as a specific unit within the larger context of cardiopulmonary pathophysiology. The Third International Right Heart Failure Summit (Boston, MA) was a multidisciplinary event dedicated to promoting a dialogue about the scientific and clinical basis of right heart disease. The current review provides a synopsis of key discussions presented during the section of the summit titled "Emerging Hemodynamic Signatures of the Right Heart." Specifically, topics emphasized in this element of the symposium included (1) the effects of pulmonary vascular dysfunction at rest or provoked by exercise on the right ventricular pressure-volume relationship, (2) the role of pressure-volume loop analysis as a method to characterize right ventricular inefficiency and predict right heart failure, and (3) the importance of a systems biology approach to identifying novel factors that contribute to pathophenotypes associated with pulmonary arterial hypertension and/or right ventricular dysfunction. Collectively, these concepts frame a forward-thinking paradigm shift in the approach to right heart disease by emphasizing factors that regulate the transition from adaptive to maladaptive right ventricular-pulmonary vascular (patho)physiology.

Independent Prognostic Value of Stroke Volume Index in Patients With Immunoglobulin Light Chain Amyloidosis.

PubMed

2018-05-01

Heart involvement is the most important prognostic determinant in AL amyloidosis patients. Echocardiography is a cornerstone for the diagnosis and provides important prognostic information. We studied 754 patients with AL amyloidosis who underwent echocardiographic assessment at the Mayo Clinic, including a Doppler-derived measurement of stroke volume (SV) within 30 days of their diagnosis to explore the prognostic role of echocardiographic variables in the context of a well-established soluble cardiac biomarker staging system. Reproducibility of SV, myocardial contraction fraction, and left ventricular strain was assessed in a separate, yet comparable, study cohort of 150 patients from the Pavia Amyloidosis Center. The echocardiographic measures most predictive for overall survival were SV index <33 mL/min, myocardial contraction fraction <34%, and cardiac index <2.4 L/min/m 2 with respective hazard ratios (95% confidence intervals) of 2.95 (2.37-3.66), 2.36 (1.96-2.85), and 2.32 (1.91-2.80). For the subset that had left ventricular strain performed, the prognostic cut point was -14% (hazard ratios, 2.70; 95% confidence intervals, 1.84-3.96). Each parameter was independent of systolic blood pressure, Mayo staging system (NT-proBNP [N-terminal pro-B-type natriuretic peptide] and troponin), and ejection fraction on multivariable analysis. Simple predictive models for survival, including biomarker staging along with SV index or left ventricular strain, were generated. SV index prognostic performance was similar to left ventricular strain in predicting survival in AL amyloidosis, independently of biomarker staging. Because SV index is routinely calculated and widely available, it could serve as the preferred echocardiographic measure to predict outcomes in AL amyloidosis patients. © 2018 American Heart Association, Inc.

Value of the Electrocardiogram as a Predictor of Right Ventricular Dysfunction in Patients With Chronic Right Ventricular Volume Overload.

PubMed

Alonso, Pau; Andrés, Ana; Rueda, Joaquín; Buendía, Francisco; Igual, Begoña; Rodríguez, María; Osa, Ana; Arnau, Miguel A; Salvador, Antonio

2015-05-01

Pulmonary regurgitation is a common complication in patients with repaired tetralogy of Fallot or congenital pulmonary stenosis. Electrocardiographic variables have been correlated with parameters used to evaluate right ventricular function. We aimed to analyze the diagnostic value of the width and fragmentation of the electrocardiogram in the identification of patients with right ventricular dysfunction and/or dilation. We selected 107 consecutive patients diagnosed with severe pulmonary insufficiency after repair of pulmonary stenosis or tetralogy of Fallot. The tests included electrocardiography, echocardiography, and magnetic resonance. Each electrocardiogram was analyzed manually to measure QRS duration. We defined QRS fragmentation as the presence of low-voltage waves in the terminal portion of the QRS complex in at least 2 contiguous leads. We found a significant negative correlation between QRS width and right ventricular function, as well as a positive correlation with right ventricular volume. The receiver operating characteristic curve indicated a cut-off point for QRS width of 140ms, which showed good sensitivity for a diagnosis of right ventricular dilation (> 80%) and dysfunction (> 95%). In logistic regression models, a QRS duration > 140ms was found to be the only independent predictor of right ventricular dilation and dysfunction. Electrocardiography is a rapid, widely available, and reproducible tool. QRS width constitutes an independent predictor of the presence of right ventricular dilation and dysfunction. This study is the first to provide a cutoff value for QRS width to screen for right ventricle involvement. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Orthostatic effects on echocardiographic measures of ventricular function.

PubMed

Rowland, Thomas; Unnithan, Viswanath; Barker, Piers; Guerra, Miriam; Roche, Denise; Lindley, Martin

2012-05-01

Orthostatic-induced alterations in Doppler echocardiographic measures of ventricular function have not been well-defined. Identifying such changes may provide useful insights regarding the responses of these measures to variations in ventricular loading conditions. Standard assessment of mitral inflow velocity and tissue Doppler imaging (TDI) of left ventricular longitudinal myocardial velocities was performed on 14 young males (mean age 17.9 ± 0.7 years) in the supine position and then 5 minutes after assuming a sitting position with legs dependent. Upon sitting, average values of stroke volume and cardiac output fell by 28% and 18%, respectively, while heart rate increased from 64 ± 10 to 73 ± 12 beats/min (+14%) and calculated systemic vascular resistance rose from 12.9 ± 2.2 to 16.4 ± 3.1 units (+27%). Mitral E peak velocity declined from 87 ± 16 to 64 ± 16 cm/sec, and average TDI-E' and TDI-S both decreased (by -44% and -20%, respectively). When adjusted for orthostatic decreases in left ventricular end-diastolic volume, the mean decrease in TDI-E' was reduced to -29 (P < 0.01), but no significant decline was observed in adjusted TDI-S. Average E/E' rose with sitting by 40% (P = 0.02). These findings suggest that (a) decreases in TDI measures when assuming the upright position reflect the reduction of left ventricular size; (b) orthostatic fall in TDI-E' is also related to smaller ventricular size but, in addition, to a nonspecified reduction in ventricular relaxation; and (c) values of E/E' do not reflect alterations in ventricular preload, which occur during an orthostatic challenge. © 2012, Wiley Periodicals, Inc.

Left ventricular morphology and diastolic function in uraemia: echocardiographic evidence of a specific cardiomyopathy.

PubMed Central

Facchin, L.; Vescovo, G.; Levedianos, G.; Zannini, L.; Nordio, M.; Lorenzi, S.; Caturelli, G.; Ambrosio, G. B.

1995-01-01

OBJECTIVE--To see whether cardiac morphological and functional abnormalities in uraemic patients are determined by high blood pressure or if they are an expression of a specific cardiomyopathy. DESIGN--Cross sectional study. SETTING--City general hospital in Italy. SUBJECTS--35 uraemic patients receiving haemodialysis (17 men, 18 women; mean age 60.3 (11.2); mean duration of dialysis 52 months) were selected from the 64 patients in Venice who were receiving dialysis; subjects with diabetes, haemochromatosis, valvar dysfunction, regional dyskinesias, and pericarditis were excluded. 19 control normotensive subjects (6 men and 13 women), matched for age. MAIN OUTCOME MEASURES--Echocardiographic measurements of left atrium, left ventricular end diastolic and end systolic volume, aortic root diameter, posterior wall and interventricular septum thickness, left ventricle mass index, and ejection fraction in controls and in patients according to whether they were normotensive (five men, eight women) or hypertensive (12 men, 10 women) on 48 hour ambulatory monitoring; left ventricular diastolic function by Doppler ultrasonography. RESULTS--Mean systolic and diastolic pressures, daytime systolic and diastolic pressures, and night time systolic and diastolic pressures were significantly higher in the hypertensive patients than in the normotensive patients. The normotensive patients had similar blood pressures to the controls. Left ventricular mass correlated significantly with the mean diastolic pressure and mean night time systolic and diastolic pressures. Parathyroid hormone concentrations were similar in the two groups of patients. Diastolic relaxation was impaired to the same degree in the two groups of patients. Parameters of diastolic function showed no relation to left ventricular mass, which was significantly higher in the hypertensive than in the normotensive patients. CONCLUSIONS--Uraemia is likely to induce specific changes in the relaxation properties of the myocardium. These changes are responsible for the impaired diastolic function independently of blood pressure, degree of hypertrophy, and metabolic changes, which suggests the existence of a specific cardiomyopathy. Hypertension remains a determinant of left ventricular mass. PMID:7546998

Cerebrospinal fluid levels of amyloid precursor protein are associated with ventricular size in post-hemorrhagic hydrocephalus of prematurity.

PubMed

Morales, Diego M; Holubkov, Richard; Inder, Terri E; Ahn, Haejun C; Mercer, Deanna; Rao, Rakesh; McAllister, James P; Holtzman, David M; Limbrick, David D

2015-01-01

Neurological outcomes of preterm infants with post-hemorrhagic hydrocephalus (PHH) remain among the worst in infancy, yet there remain few instruments to inform the treatment of PHH. We previously observed PHH-associated elevations in cerebrospinal fluid (CSF) amyloid precursor protein (APP), neural cell adhesion molecule-L1 (L1CAM), neural cell adhesion molecule-1 (NCAM-1), and other protein mediators of neurodevelopment. The objective of this study was to examine the association of CSF APP, L1CAM, and NCAM-1 with ventricular size as an early step toward developing CSF markers of PHH. CSF levels of APP, L1CAM, NCAM-1, and total protein (TP) were measured in 12 preterm infants undergoing PHH treatment. Ventricular size was determined using cranial ultrasounds. The relationships between CSF APP, L1CAM, and NCAM-1, occipitofrontal circumference (OFC), volume of CSF removed, and ventricular size were examined using correlation and regression analyses. CSF levels of APP, L1CAM, and NCAM-1 but not TP paralleled treatment-related changes in ventricular size. CSF APP demonstrated the strongest association with ventricular size, estimated by frontal-occipital horn ratio (FOR) (Pearson R = 0.76, p = 0.004), followed by NCAM-1 (R = 0.66, p = 0.02) and L1CAM (R = 0.57,p = 0.055). TP was not correlated with FOR (R = 0.02, p = 0.95). Herein, we report the novel observation that CSF APP shows a robust association with ventricular size in preterm infants treated for PHH. The results from this study suggest that CSF APP and related proteins at once hold promise as biomarkers of PHH and provide insight into the neurological consequences of PHH in the preterm infant.

Age-related ventricular-vascular coupling during acute inflammation in humans: Effect of physical activity.

PubMed

Lane, Abbi D; Kappus, Rebecca M; Bunsawat, Kanokwan; Ranadive, Sushant M; Yan, Huimin; Phillips, Shane; Baynard, Tracy; Woods, Jeffrey A; Motl, Robert; Fernhall, Bo

2015-07-01

Aging is commonly accompanied by increased arterial and ventricular stiffness (determined by arterial elastance (Ea) and ventricular elastance (Elv)), augmented ventricular-vascular coupling ratios (Ea/Elv) and systemic inflammation. Acute inflammation may impact ventricular-vascular coupling and predispose older adults to cardiovascular events. However, physically active older adults have more compliant large arteries and left ventricles and lower inflammation than sedentary older adults. We hypothesized that acute inflammation would alter Ea, Elv, and Ea/Elv more in older versus younger adults but that higher levels of physical activity would attenuate inflammation-induced changes. End-systolic and central blood pressures were obtained using applanation tonometry before and at 24 and 48 h post-influenza vaccination in 24 older and 38 younger adults. Ultrasonography was used to measure ventricular volumes and other indices of cardiac performance. Physical activity was measured with accelerometry. Ea and Ea/Elv were maintained (p > 0.05), but Elv was reduced (p < 0.05) 24 h post-inflammation. Other indices of systolic performance were reduced in older but not younger adults; diastolic performance was attenuated in both groups 24 h post-inflammation (p < 0.05 for all). Older, but not younger, adults decreased central pressure during inflammation (p < 0.05). When controlled for age, physical activity was not related to the inflammation-induced changes in elastance (p > 0.05) except in the most active group of seniors (p < 0.05). Aging did not affect the elastance responses but did affect central blood pressure and other ventricular systolic responses to acute inflammation. Aging, not physical activity, appears to modulate cardiovascular responses to acute inflammation, except in the most active older adults. © The European Society of Cardiology 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Sedentary Screen Time and Left Ventricular Structure and Function: the CARDIA Study

PubMed Central

Gibbs, Bethany Barone; Reis, Jared P.; Schelbert, Erik B.; Craft, Lynette L.; Sidney, Steve; Lima, Joao; Lewis, Cora E.

2013-01-01

Sedentary screen time (watching TV or using a computer) predicts cardiovascular outcomes independently from moderate and vigorous physical activity and could impact left ventricular structure and function through the adverse consequences of sedentary behavior. Purpose To determine whether sedentary screen time is associated with measures of left ventricular structure and function. Methods The Coronary Artery Risk Development in Young Adults (CARDIA) Study measured screen time by questionnaire and left ventricular structure and function by echocardiography in 2,854 black and white participants, aged 43–55 years, in 2010–2011. Generalized linear models evaluated cross-sectional trends for echocardiography measures across higher categories of screen time and adjusting for demographics, smoking, alcohol, and physical activity. Further models adjusted for potential intermediate factors (blood pressure, antihypertensive medication use, diabetes, and body mass index (BMI). Results The relationship between screen time and left ventricular mass(LVM) differed in blacks vs. whites. Among whites, higher screen time was associated with larger LVM (P<0.001), after adjustment for height, demographics, and lifestyle variables. Associations between screen time and LVM persisted when adjusting for blood pressure, antihypertensive medication use, and diabetes (P=0.008) but not with additional adjustment for BMI (P=0.503). Similar relationships were observed for screen time with LVM indexed to height2.7, relative wall thickness, and mass-to-volume ratio. Screen time was not associated with left ventricular structure among blacks or left ventricular function in either race group. Conclusions Sedentary screen time is associated with greater LVM in white adults and this relationship was largely explained by higher overall adiposity. The lack of association in blacks supports a potential qualitative difference in the cardiovascular consequences of sedentary screen-based behavior. PMID:23863618

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.

Beta-erythropoietin effects on ventricular remodeling, left and right systolic function, pulmonary pressure, and hospitalizations in patients affected with heart failure and anemia.

PubMed

Palazzuoli, Alberto; Silverberg, Donald S; Calabrò, Anna; Spinelli, Tommaso; Quatrini, Ilaria; Campagna, Maria S; Franci, Beatrice; Nuti, Ranuccio

2009-06-01

Anemia in heart failure is related to advanced New York Heart Association classes, severe systolic dysfunction, and reduced exercise tolerance. Although anemia is frequently found in congestive heart failure (CHF), little is known about the effect of its' correction with erythropoietin (EPO) on cardiac structure and function. The present study examines, in patients with advanced CHF and anemia, the effects of beta-EPO on left ventricular volumes, left ventricular ejection fraction (LVEF), left and right longitudinal function mitral anular plane systolic excursion (MAPSE), tricuspid anular plane excursion (TAPSE), and pulmonary artery pressures in 58 patients during 1-year follow-up in a double-blind controlled study of correction of anemia with subcutaneous beta-EPO. Echocardiographic evaluation, B-Type natriuretic peptide (BNP) levels, and hematological parameters are reported at 4 and 12 months. The patients in group A after 4 months of follow-up period demonstrated an increase in LVEF and MAPSE (P < 0.05 and P < 0.01, respectively) with left ventricular systolic volume reduction (P < 0.02) with respect to baseline and controls. After 12 months, results regarding left ventricular systolic volume LVEF and MAPSE persisted (P < 0.001). In addition, TAPSE increased and pulmonary artery pressures fell significantly in group A (P < 0.01). All these changes occurred together with a significant BNP reduction and significant hemoglobin increase in the treated group. Therefore, we revealed a reduced hospitalization rate in treated patients with respect to the controls (25% in treated vs. 54% in controls). In patients with anemia and CHF, correction of anemia with beta-EPO and oral iron over 1 year leads to an improvement in left and right ventricular systolic function by reducing cardiac remodeling, BNP levels, and hospitalization rate.

Outflow monitoring of a pneumatic ventricular assist device using external pressure sensors.

PubMed

Kang, Seong Min; Her, Keun; Choi, Seong Wook

2016-08-25

In this study, a new algorithm was developed for estimating the pump outflow of a pneumatic ventricular assist device (p-VAD). The pump outflow estimation algorithm was derived from the ideal gas equation and determined the change in blood-sac volume of a p-VAD using two external pressure sensors. Based on in vitro experiments, the algorithm was revised to consider the effects of structural compliance caused by volume changes in an implanted unit, an air driveline, and the pressure difference between the sensors and the implanted unit. In animal experiments, p-VADs were connected to the left ventricles and the descending aorta of three calves (70-100 kg). Their outflows were estimated using the new algorithm and compared to the results obtained using an ultrasonic blood flow meter (UBF) (TS-410, Transonic Systems Inc., Ithaca, NY, USA). The estimated and measured values had a Pearson's correlation coefficient of 0.864. The pressure sensors were installed at the external controller and connected to the air driveline on the same side as the external actuator, which made the sensors easy to manage.

Prevalence and Prognostic Significance of Right Ventricular Systolic Dysfunction in Patients Undergoing Transcatheter Aortic Valve Implantation.

PubMed

Lindsay, Alistair C; Harron, Katie; Jabbour, Richard J; Kanyal, Ritesh; Snow, Thomas M; Sawhney, Paramvir; Alpendurada, Francisco; Roughton, Michael; Pennell, Dudley J; Duncan, Alison; Di Mario, Carlo; Davies, Simon W; Mohiaddin, Raad H; Moat, Neil E

2016-07-01

Cardiovascular magnetic resonance (CMR) can provide important structural information in patients undergoing transcatheter aortic valve implantation. Although CMR is considered the standard of reference for measuring ventricular volumes and mass, the relationship between CMR findings of right ventricular (RV) function and outcomes after transcatheter aortic valve implantation has not previously been reported. A total of 190 patients underwent 1.5 Tesla CMR before transcatheter aortic valve implantation. Steady-state free precession sequences were used for aortic valve planimetry and to assess ventricular volumes and mass. Semiautomated image analysis was performed by 2 specialist reviewers blinded to patient treatment. Patient follow-up was obtained from the Office of National Statistics mortality database. The median age was 81.0 (interquartile range, 74.9-85.5) years; 50.0% were women. Impaired RV function (RV ejection fraction ≤50%) was present in 45 (23.7%) patients. Patients with RV dysfunction had poorer left ventricular ejection fractions (42% versus 69%), higher indexed left ventricular end-systolic volumes (96 versus 40 mL), and greater indexed left ventricular mass (101 versus 85 g/m(2); P<0.01 for all) than those with normal RV function. Median follow-up was 850 days; 21 of 45 (46.7%) patients with RV dysfunction died, compared with 43 of 145 (29.7%) patients with normal RV function (P=0.035). After adjustment for significant baseline variables, both RV ejection fraction ≤50% (hazard ratio, 2.12; P=0.017) and indexed aortic valve area (hazard ratio, 4.16; P=0.025) were independently associated with survival. RV function, measured on preprocedural CMR, is an independent predictor of mortality after transcatheter aortic valve implantation. CMR assessment of RV function may be important in the risk stratification of patients undergoing transcatheter aortic valve implantation. © 2016 American Heart Association, Inc.

Left atrial volume is not an index of left ventricular diastolic dysfunction in patients with sickle cell anaemia.

PubMed

Hammoudi, Nadjib; Charbonnier, Magali; Levy, Pierre; Djebbar, Morad; Stankovic Stojanovic, Katia; Ederhy, Stéphane; Girot, Robert; Cohen, Ariel; Isnard, Richard; Lionnet, François

2015-03-01

Left ventricular diastolic dysfunction (LVDD) is common in sickle cell anaemia (SCA). Left atrial (LA) size is widely used as an index of LVDD; however, LA enlargement in SCA might also be due to chronic volume overload. To investigate whether LA size can be used to diagnose LVDD in SCA. One hundred and twenty-seven adults with stable SCA underwent echocardiographic assessment. LA volume was measured by the area-length method and indexed to body surface area (LAVi). Left ventricular (LV) filling pressures were assessed using the ratio of early peak diastolic velocities of mitral inflow and septal annular mitral plane (E/e'). Using mitral inflow profile and E/e', LV diastolic function was classified as normal or abnormal. LAVi>28mL/m(2) was used as the threshold to define LA enlargement. The mean age was 28.6±8.5years; there were 83 women. Mean LAVi was 48.3±11.1mL/m(2) and 124 (98%) patients had LA dilatation. In multivariable analysis, age, haemoglobin concentration and LV end-diastolic volume index were independent determinants of LAVi (R(2)=0.51; P<0.0001). E/e' was not linked to LAVi (P=0.43). Twenty patients had LVDD; when compared with patients without LVDD, they had a similar LAVi (52.2±14.7 and 47.5±10.2mL/m(2), respectively; P=0.29). Receiver operating characteristics curve analysis showed that LAVi could not be used to diagnose LVDD (area under curve=0.58; P=0.36). LA enlargement is common in SCA but appears not to be linked to LVDD. LAVi in this population is related to age, haemoglobin concentration and LV morphology. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Three-dimensional mapping of the lateral ventricles in autism

PubMed Central

Vidal, Christine N.; Nicolsonln, Rob; Boire, Jean-Yves; Barra, Vincent; DeVito, Timothy J.; Hayashi, Kiralee M.; Geaga, Jennifer A.; Drost, Dick J.; Williamson, Peter C.; Rajakumar, Nagalingam; Toga, Arthur W.; Thompson, Paul M.

2009-01-01

In this study, a computational mapping technique was used to examine the three-dimensional profile of the lateral ventricles in autism. T1-weighted three-dimensional magnetic resonance images of the brain were acquired from 20 males with autism (age: 10.1 ± 3.5 years) and 22 male control subjects (age: 10.7 ± 2.5 years). The lateral ventricles were delineated manually and ventricular volumes were compared between the two groups. Ventricular traces were also converted into statistical three-dimensional maps, based on anatomical surface meshes. These maps were used to visualize regional morphological differences in the thickness of the lateral ventricles between patients and controls. Although ventricular volumes measured using traditional methods did not differ significantly between groups, statistical surface maps revealed subtle, highly localized reductions in ventricular size in patients with autism in the left frontal and occipital horns. These localized reductions in the lateral ventricles may result from exaggerated brain growth early in life. PMID:18502618

Cannabinoid receptor 2 activation restricts fibrosis and alleviates hydrocephalus after intraventricular hemorrhage.

PubMed

Tan, Qiang; Chen, Qianwei; Feng, Zhou; Shi, Xia; Tang, Jun; Tao, Yihao; Jiang, Bing; Tan, Liang; Feng, Hua; Zhu, Gang; Yang, Yunfeng; Chen, Zhi

2017-01-01

Fibrosis in ventricular system has a role in hydrocephalus following intraventricular hemorrhage (IVH). The cannabinoid receptor 2 (CB2) has been reported to participate in alleviating the fibrosis process of many diseases. However, its role in fibrosis after IVH was unclear so far, and we hypothesized that CB2 activation has potential to attenuate hydrocephalus after IVH via restricting fibrosis. So the present study was designed to investigate this hypothesis in a modified rat IVH model. Autologous non-anticoagulative blood injection model was induced to mimic ventricular extension of hemorrhage in adult Sprague-Dawley rats. Rats were randomized to receive JWH-133(CB2 agonist), SR144528 (CB2 antagonist) or saline. The lateral ventricular volumes, fibrosis in the subarachnoid space and ventricular wall, transforming growth factor-β 1(TGF-β1) in cerebrospinal fluid and brain tissue, and animal neurological scores were measured to evaluate the effects of CB2 in hydrocephalus following IVH. CB2 agonist JWH-133 significantly decreased the lateral ventricular volumes, improved the associated neurological deficits, down-regulated TGF-β1 expression, and alleviated fibrosis in the subarachnoid space and ventricular wall after IVH. All of these effects were reversed by SR144528. In conclusion, CB2 may have anti-fibrogenic effects after IVH. CB2 agonist suppressed fibrosis of ventricular system and alleviated hydrocephalus following IVH, which is partly mediated by inhibiting TGF-β1. Copyright © 2016 Elsevier B.V. All rights reserved.

Relationship between cardiac diffusion tensor imaging parameters and anthropometrics in healthy volunteers.

PubMed

McGill, L A; Ferreira, P F; Scott, A D; Nielles-Vallespin, S; Giannakidis, A; Kilner, P J; Gatehouse, P D; de Silva, R; Firmin, D N; Pennell, D J

2016-01-06

In vivo cardiac diffusion tensor imaging (cDTI) is uniquely capable of interrogating laminar myocardial dynamics non-invasively. A comprehensive dataset of quantative parameters and comparison with subject anthropometrics is required. cDTI was performed at 3T with a diffusion weighted STEAM sequence. Data was acquired from the mid left ventricle in 43 subjects during the systolic and diastolic pauses. Global and regional values were determined for fractional anisotropy (FA), mean diffusivity (MD), helix angle gradient (HAg, degrees/%depth) and the secondary eigenvector angulation (E2A). Regression analysis was performed between global values and subject anthropometrics. All cDTI parameters displayed regional heterogeneity. The RR interval had a significant, but clinically small effect on systolic values for FA, HAg and E2A. Male sex and increasing left ventricular end diastolic volume were associated with increased systolic HAg. Diastolic HAg and systolic E2A were both directly related to left ventricular mass and body surface area. There was an inverse relationship between E2A mobility and both age and ejection fraction. Future interpretations of quantitative cDTI data should take into account anthropometric variations observed with patient age, body surface area and left ventricular measurements. Further work determining the impact of technical factors such as strain and SNR is required.

Simulation of 'pathologic' changes in ICG waveforms resulting from superposition of the 'preejection' and ejection waves induced by left ventricular contraction

NASA Astrophysics Data System (ADS)

Ermishkin, V. V.; Kolesnikov, V. A.; Lukoshkova, E. V.; Sonina, R. S.

2013-04-01

The impedance cardiography (ICG) is widely used for beat-to-beat noninvasive evaluation of the left ventricular stroke volume and contractility. It implies the correct determination of the ejection start and end points and the amplitudes of certain peaks in the differentiated impedance cardiogram. An accurate identification of ejection onset by ICG is often problematic, especially in the cardiologic patients, due to peculiar waveforms. Using a simple theoretical model, we tested the hypothesis that two major processes are responsible for the formation of impedance systolic wave: (1) the changes in the heart geometry and surrounding vessels produced by ventricular contraction, which occur during the isovolumic phase and precede ejection, and (2) expansion of aorta and adjacent arteries during the ejection phase. The former process initiates the preejection wave WpE and the latter triggers the ejection wave WEj. The model predicts a potential mechanism of generating the abnormal shapes of dZ/dt due to the presence of preejection waves and explains the related errors in ICG time and amplitude parameters. An appropriate decomposition method is a promising way to avoid the masking effects of these waves and a further step to correct determination of the onset of ejection and the corresponding peak amplitudes from 'pathologically shaped' ICG signals.

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.

Long-term Results After Open Mitral Commissurotomy for a One-Month-Old Infant With Mitral Stenosis.

PubMed

Kitaichi, Takashi; Sugano, Mikio; Arase, Hiroki; Kawatani, Yohei; Kameta, Kanako; Kurobe, Hirotsugu; Fujimoto, Eiki; Ono, Akemi; Hayabuchi, Yasunobu; Fujita, Hiroshi; Sogabe, Hitoshi; Kitagawa, Tetsuya

2017-01-01

The strategy for an infant with congenital mitral stenosis should be determined by three important factors: left ventricular volume, the degree of the systemic outflow tract obstruction, and the type of mitral valve dysfunction. A successful staged biventricular repair in early infancy for a patient who had congenital mitral stenosis with short chordae, hypoplastic left ventricle and coarctation of the aorta, and the long-term results are described. There were the following important hemodynamic factors that led to the successful biventricular repair in the patient. Total systemic output was barely supplied through the hypoplastic left ventricle after closure of the ductus arteriosus on admission. The neonate underwent repair of coarctation of the aorta alone as the initial stage at 9 days after birth. Also, spontaneous closure of the foramen ovale following repair of coarctation of the aorta accelerated the progressive left ventricular growth. Open mitral commissurotomy with an interatrial fenestration using the modified Brawley's approach was performed for a 40-day-old infant. Good left ventricular growth and good mitral valve function have been observed for 18 years after open mitral commissurotomy. Appropriate early augmentation of left ventricular inflow through the mitral valve might be effective for growth of a hypoplastic left ventricle. J. Med. Invest. 64: 187-191, February, 2017.

The angulation of the septal structures impacts ventricular imbalance in atrioventricular septal defects with a common atrioventricular junction.

PubMed

Ahmad, Zaheer; Lim, Zek; Roman, Kevin; Haw, Marcus; Anderson, Robert H; Vettukattil, Joseph

2016-02-01

Multiplanar re-formatting of full-volume three-dimensional echocardiography data sets offers new insights into the morphology of atrioventricular septal defects. We hypothesised that distortion of the alignment between the atrial and ventricular septums results in imbalanced venous return to the ventricles, with consequent proportional ventricular hypoplasia. A single observer evaluated 31 patients, with a mean age of 52.09 months, standard deviation of 55, and with a range from 2 to 264 months, with atrioventricular septal defects, of whom 17 were boys. Ventricular imbalance, observed in nine patients, was determined by two-dimensional assessment, and confirmed at surgical inspection in selected cases when a univentricular strategy was undertaken. Offline analysis using multiplanar re-formatting was performed. A line was drawn though the length of the ventricular septum and a second line along the plane of the atrial septum, taking the angle between these two lines as the atrioventricular septal angle. We compared the angle between 22 patients with adequately sized ventricles, and those with ventricular imbalance undergoing univentricular repair. In the 22 patients undergoing biventricular repair, the septal angle was 0 in 14 patients; the other eight patients having angles ranging from 1 to 36, with a mean angle of 7.4°, and standard deviation of 11.1°.The mean angle in the nine patients with ventricle imbalance was 28.6°, with a standard deviation of 3.04°, and with a range from 26 to 35°. Of those undergoing univentricular repair, two patients died, with angles of 26 and 30°, respectively. The atrioventricular septal angle derived via multiplanar formatting gives important information regarding the degree of ventricular hypoplasia and imbalance. When this angle is above 25°, patients are likely to have ventricular imbalance requiring univentricular repair.

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

Guiding automated left ventricular chamber segmentation in cardiac imaging using the concept of conserved myocardial volume.

PubMed

Garson, Christopher D; Li, Bing; Acton, Scott T; Hossack, John A

2008-06-01

The active surface technique using gradient vector flow allows semi-automated segmentation of ventricular borders. The accuracy of the algorithm depends on the optimal selection of several key parameters. We investigated the use of conservation of myocardial volume for quantitative assessment of each of these parameters using synthetic and in vivo data. We predicted that for a given set of model parameters, strong conservation of volume would correlate with accurate segmentation. The metric was most useful when applied to the gradient vector field weighting and temporal step-size parameters, but less effective in guiding an optimal choice of the active surface tension and rigidity parameters.

Non-invasive estimation of pulmonary artery pressures in patients with sickle cell anaemia in Ibadan, Nigeria: an echocardiographic study.

PubMed

Enakpene, Evbu O; Adebiyi, Adewole A; Ogah, Okechukwu S; Olaniyi, John A; Aje, Akinyemi; Adeoye, Moshood A; Falase, Ayodele O

2014-10-01

Pulmonary hypertension is emerging as one of the causes of morbidity and mortality in adults with sickle cell disease. The prevalence of pulmonary hypertension in Nigerian adults with sickle cell anaemia is unknown. We decided to estimate the pulmonary artery systolic and diastolic pressures in subjects with sickle cell anaemia seen at the University College Hospital, Ibadan, Nigeria, and to determine the frequency of pulmonary hypertension among them. Ninety patients (38 males and 52 females) with sickle cell anaemia in steady state and comparable age- and sex-matched normal controls had a clinical evaluation and echocardiographic examination. The mean age of the subjects with sickle cell anaemia was 24.0 (9.00) years while the mean age for the control group was 24.0 (7.00) years. The frequency of pulmonary hypertension as assessed by a tricuspid regurgitant jet velocity of > 2.5 m/s in this study was 12.2%. Larger left ventricular dimensions and volumes, higher stroke volume and increased left ventricular mass indexed by body surface area were found to be associated with pulmonary hypertension. A multivariate analysis of the potential predictors of pulmonary hypertension in this study showed that male sex and lower packed cell volume (PCV) were independent predictors of pulmonary hypertension in patients with sickle cell anaemia. We conclude that pulmonary artery systolic and diastolic pressures are higher in subjects with sickle cell disease than normal controls. Male sex and low PCV are independent determinants of pulmonary arterial pressure in subjects with sickle cell anaemia in Nigeria.

Evaluation of global and regional right ventricular systolic function in patients with pulmonary hypertension using a novel speckle tracking method.

PubMed

Pirat, Bahar; McCulloch, Marti L; Zoghbi, William A

2006-09-01

This study sought to demonstrate that a novel speckle-tracking method can be used to assess right ventricular (RV) global and regional systolic function. Fifty-eight patients with pulmonary arterial hypertension (11 men; mean age 53 +/- 14 years) and 19 age-matched controls were studied. Echocardiographic images in apical planes were analyzed by conventional manual tracing for volumes and ejection fractions and by novel software (Axius Velocity Vector Imaging). Myocardial velocity, strain rate, and strain were determined at the basal, mid, and apical segments of the RV free wall and ventricular septum by Velocity Vector Imaging. RV volumes and ejection fractions obtained with manual tracing correlated strongly with the same indexes obtained by the Velocity Vector Imaging method in all subjects (r = 0.95 to 0.98, p < 0.001 for all). Peak systolic myocardial velocities, strain rate, and strain were significantly impaired in patients with pulmonary arterial hypertension compared with controls and were most altered in patients with the most severe pulmonary arterial hypertension (p < 0.05 for all). Pulmonary artery systolic pressure and a Doppler index of pulmonary vascular resistance were independent predictors of RV strain (r = -0.61 and r = -0.65, respectively, p < 0.05 for both). In conclusion, the new automated Velocity Vector Imaging method provides simultaneous quantitation of global and regional RV function that is angle independent and can be applied retrospectively to already stored digital images.

[Experts consensus on the management of the right heart function in critically ill patients].

PubMed

Wang, X T; Liu, D W; Zhang, H M; Long, Y; Guan, X D; Qiu, H B; Yu, K J; Yan, J; Zhao, H; Tang, Y Q; Ding, X; Ma, X C; Du, W; Kang, Y; Tang, B; Ai, Y H; He, H W; Chen, D C; Chen, H; Chai, W Z; Zhou, X; Cui, N; Wang, H; Rui, X; Hu, Z J; Li, J G; Xu, Y; Yang, Y; Ouyan, B; Lin, H Y; Li, Y M; Wan, X Y; Yang, R L; Qin, Y Z; Chao, Y G; Xie, Z Y; Sun, R H; He, Z Y; Wang, D F; Huang, Q Q; Jiang, D P; Cao, X Y; Yu, R G; Wang, X; Chen, X K; Wu, J F; Zhang, L N; Yin, M G; Liu, L X; Li, S W; Chen, Z J; Luo, Z

2017-12-01

To establish the experts consensus on the right heart function management in critically ill patients. The panel of consensus was composed of 30 experts in critical care medicine who are all members of Critical Hemodynamic Therapy Collaboration Group (CHTC Group). Each statement was assessed based on the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) principle. Then the Delphi method was adopted by 52 experts to reassess all the statements. (1) Right heart function is prone to be affected in critically illness, which will result in a auto-exaggerated vicious cycle. (2) Right heart function management is a key step of the hemodynamic therapy in critically ill patients. (3) Fluid resuscitation means the process of fluid therapy through rapid adjustment of intravascular volume aiming to improve tissue perfusion. Reversed fluid resuscitation means reducing volume. (4) The right ventricle afterload should be taken into consideration when using stroke volume variation (SVV) or pulse pressure variation (PPV) to assess fluid responsiveness.(5)Volume overload alone could lead to septal displacement and damage the diastolic function of the left ventricle. (6) The Starling curve of the right ventricle is not the same as the one applied to the left ventricle,the judgement of the different states for the right ventricle is the key of volume management. (7) The alteration of right heart function has its own characteristics, volume assessment and adjustment is an important part of the treatment of right ventricular dysfunction (8) Right ventricular enlargement is the prerequisite for increased cardiac output during reversed fluid resuscitation; Nonetheless, right heart enlargement does not mandate reversed fluid resuscitation.(9)Increased pulmonary vascular resistance induced by a variety of factors could affect right heart function by obstructing the blood flow. (10) When pulmonary hypertension was detected in clinical scenario, the differentiation of critical care-related pulmonary hypertension should be a priority. (11) Attention should be paid to the change of right heart function before and after implementation of mechanical ventilation and adjustment of ventilator parameter. (12) The pulmonary arterial pressure should be monitored timingly when dealing with critical care-related pulmonary hypertension accompanied with circulatory failure.(13) The elevation of pulmonary aterial pressure should be taken into account in critical patients with acute right heart dysfunction. (14) Prone position ventilation is an important measure to reduce pulmonary vascular resistance when treating acute respiratory distress syndrome patients accompanied with acute cor pulmonale. (15) Attention should be paid to right ventricle-pulmonary artery coupling during the management of right heart function. (16) Right ventricular diastolic function is more prone to be affected in critically ill patients, the application of critical ultrasound is more conducive to quantitative assessment of right ventricular diastolic function. (17) As one of the parameters to assess the filling pressure of right heart, central venous pressure can be used to assess right heart diastolic function. (18). The early and prominent manifestation of non-focal cardiac tamponade is right ventricular diastolic involvement, the elevated right atrial pressure should be noticed. (19) The effect of increased intrathoracic pressure on right heart diastolic function should be valued. (20) Ttricuspid annular plane systolic excursion (TAPSE) is an important parameter that reflects right ventricular systolic function, and it is recommended as a general indicator of critically ill patient. (21) Circulation management with right heart protection as the core strategy is the key point of the treatment of acute respiratory distress syndrome. (22) Right heart function involvement after cardiac surgery is very common and should be highly valued. (23) Right ventricular dysfunction should not be considered as a routine excuse for maintaining higher central venous pressure. (24) When left ventricular dilation, attention should be paid to the effect of left ventricle on right ventricular diastolic function. (25) The impact of left ventricular function should be excluded when the contractility of the right ventricle is decreased. (26) When the right heart load increases acutely, the shunt between the left and right heart should be monitored. (27) Attention should be paid to the increase of central venous pressure caused by right ventricular dysfunction and its influence on microcirculation blood flow. (28) When the vasoactive drugs was used to reduce the pressure of pulmonary circulation, different effects on pulmonary and systemic circulation should be evaluated. (29) Right atrial pressure is an important factor affecting venous return. Attention should be paid to the influence of the pressure composition of the right atrium on the venous return. (30) Attention should be paid to the role of the right ventricle in the acute pulmonary edema. (31) Monitoring the difference between the mean systemic filling pressure and the right atrial pressure is helpful to determine whether the infusion increases the venous return. (32) Venous return resistance is often considered to be a insignificant factor that affects venous return, but attention should be paid to the effect of the specific pathophysiological status, such as intrathoracic hypertension, intra-abdominal hypertension and so on. Consensus can promote right heart function management in critically ill patients, optimize hemodynamic therapy, and even affect prognosis.

Impact of age, sex, and indexation method on MR left ventricular reference values in the Framingham Heart Study offspring cohort.

PubMed

Yeon, Susan B; Salton, Carol J; Gona, Philimon; Chuang, Michael L; Blease, Susan J; Han, Yuchi; Tsao, Connie W; Danias, Peter G; Levy, Daniel; O'Donnell, Christopher J; Manning, Warren J

2015-04-01

To determine normative values for left ventricular (LV) volumes, mass, concentricity, and ejection fraction (EF) and investigate associations between sex, age, and body size with LV parameters in community-dwelling adults. In all, 1794 Framingham Heart Study Offspring cohort members underwent LV short-axis oriented, contiguous multislice cine steady-state free precession MR of the left ventricle; from these a healthy referent group (n = 852, 61 ± 9 years, 40% men) free of clinical cardiac disease and hypertension (SBP < 140, DBP < 90 mmHg, never used antihypertensive medication ≥30 years prior to scanning) was identified. Referent participants were stratified by sex and age group (≤55, 56-65, >65 years); LV parameters were indexed to measures of body size. Men have greater LV volumes and mass than women both before and after indexation to height, powers of height, and body surface area (P < 0.01 all), but indexation to fat-free mass yielded greater LV volume and mass in women. In both sexes, LV volumes and mass decrease with advancing age, although indexation attenuates this association. LVEF is greater in women than men (68 ± 5% vs. 66 ± 5%, P < 0.01) and increases with age in both sexes (P < 0.05). Among nonhypertensive adults free of cardiac disease, men have greater LV volumes and mass with sex differences generally persisting after indexation to body size. LV volumes and mass tend to decrease with greater age in both sexes. Female sex and advanced age were both associated with greater LVEF. J. Magn. Reson. Imaging 2015;41:1038-1045. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

Evaluation of a new 3-dimensional color Doppler flow method to quantify flow across the mitral valve and in the left ventricular outflow tract: an in vitro study.

PubMed

Kimura, Sumito; Streiff, Cole; Zhu, Meihua; Shimada, Eriko; Datta, Saurabh; Ashraf, Muhammad; Sahn, David J

2014-02-01

The aim of this study was to assess the accuracy, feasibility, and reproducibility of determining stroke volume from a novel 3-dimensional (3D) color Doppler flow quantification method for mitral valve (MV) inflow and left ventricular outflow tract (LVOT) outflow at different stroke volumes when compared with the actual flow rate in a pumped porcine cardiac model. Thirteen freshly harvested pig hearts were studied in a water tank. We inserted a latex balloon into each left ventricle from the MV annulus to the LVOT, which were passively pumped at different stroke volumes (30-80 mL) using a calibrated piston pump at increments of 10 mL. Four-dimensional flow volumes were obtained without electrocardiographic gating. The digital imaging data were analyzed offline using prototype software. Two hemispheric flow-sampling planes for color Doppler velocity measurements were placed at the MV annulus and LVOT. The software computed the flow volumes at the MV annulus and LVOT within the user-defined volume and cardiac cycle. This novel 3D Doppler flow quantification method detected incremental increases in MV inflow and LVOT outflow in close agreement with pumped stroke volumes (MV inflow, r = 0.96; LVOT outflow, r = 0.96; P < .01). Bland-Altman analysis demonstrated overestimation of both (MV inflow, 5.42 mL; LVOT outflow, 4.46 mL) with 95% of points within 95% limits of agreement. Interobserver variability values showed good agreement for all stroke volumes at both the MV annulus and LVOT. This study has shown that the 3D color Doppler flow quantification method we used is able to compute stroke volumes accurately at the MV annulus and LVOT in the same cardiac cycle without electrocardiographic gating. This method may be valuable for assessment of cardiac output in clinical studies.

[Assessment of the right ventricular function in healthy volunteers with one beat full-volume real-time three-dimensional echocardiography].

PubMed

Zhu, Wei-hong; Zhang, Jin; Tong, Kai; Zhi, Guang; He, Kun-lun

2012-08-01

To determine the normal value of right ventricle using one beat full-volume real-time three-dimensional echocardiography (RT-3DE) and assess the feasibility of this technique. One beat full volume images were acquired at the apical 4 chamber view in 129 healthy volunteers. The right and left ventricular volumes were examined with the eSie LVA and RVA. The subjects were divided into 2 gender groups (male and female) and 3 age groups (20 - 39 years old, 40 - 59 years old, 60 years old and above). Adequate data were obtained in 129 subjects. The RV-EDV was (92.4 ± 21.3) ml, RV-ESV (34.6 ± 9.2) ml, RV-SV (57.8 ± 13.9) ml, RV-EF (62.5 ± 5.0) ml. EDV, ESV, and EF were significant different while SV was similar between RV and LV (all P < 0.05). RV-EDV (r = 0.517, P = 0.001), RV-ESV (r = 0.588, P = 0.001) and RV-SV(r = 0.409, P = 0.001) were correlated well with BSA. RV-EDV, RV-ESV and RV-SV were significantly higher in males than in females (all P < 0.001). RV-EDV, RV-SV and RV-EF decreased with aging (P < 0.05). Right ventricle function can be measured noninvasively by RT-3DE with high feasibility. This novel method contributes to the detailed study of right heart function in various cardiovascular diseases.

Cortical magnetic resonance imaging findings in familial pediatric bipolar disorder.

PubMed

Chang, Kiki; Barnea-Goraly, Naama; Karchemskiy, Asya; Simeonova, Diana Iorgova; Barnes, Patrick; Ketter, Terence; Reiss, Allan L

2005-08-01

Morphometric magnetic resonance imaging (MRI) studies of pediatric bipolar disorder (BD) have not reported on gray matter volumes but have reported increased lateral ventricular size and presence of white matter hyperintensities (WMH). We studied gray matter volume, ventricular-to-brain ratios (VBR), and number of WMH in patients with familial, pediatric BD compared with control subjects. Twenty subjects with BD (aged 14.6 +/- 2.8 years; 4 female) according to the Washington University in St. Louis Kiddie Schedule for Affective Disorders and Schizophrenia, each with a parent with BD, and 20 age-, gender-, and intelligence quotient-matched healthy control subjects (aged 14.1 +/- 2.8 years; 4 female) were scanned at 3 T. Most subjects were taking psychotropic medications. A high-resolution T1-weighted spoiled gradient echo three-dimensional MRI sequence was analyzed by BrainImage for volumetric measurements, and T2-weighted images were read by a neuroradiologist to determine presence of WMH. After covarying for age and total brain volume, there were no significant differences between subjects with BD and control subjects in volume of cerebral (p = .09) or prefrontal gray matter (p = .34). Subjects with BD did not have elevated numbers of WMH or greater VBR when compared with control subjects. Children and adolescents with familial BD do not seem to have decreased cerebral grey matter or increased numbers of WMH, dissimilar to findings in adults with BD. Gray matter decreases and development of WMH might be later sequelae of BD or unique to adult-onset BD.

Relationship Between Central and Peripheral Atherosclerosis and Left Ventricular Dysfunction in a Community Population

PubMed Central

Tsao, Connie W.; Gona, Philimon; Salton, Carol; Murabito, Joanne M.; Oyama, Noriko; Danias, Peter G.; O’Donnell, Christopher J.; Manning, Warren J.; Yeon, Susan B.

2011-01-01

We aimed to determine the relationships between resting left ventricular (LV) wall motion abnormalities (WMAs), aortic plaque, and PAD in a community cohort. 1726 Framingham Heart Study Offspring Cohort participants (806 males, 65±9 years) underwent cardiovascular magnetic resonance with quantification of aortic plaque volume and assessment of regional LV systolic function. Claudication, lower extremity revascularization, and ankle-brachial index (ABI) were recorded at Examination 7. WMAs were associated with greater aortic plaque burden, decreased ABI, and claudication in age- and sex-adjusted analyses (all p<0.001), which were not significant after adjustment for cardiovascular risk factors. In age- and sex-adjusted analyses, both the presence (p<0.001) and volume of aortic plaque were associated with decreased ABI (p<0.001). After multivariable adjustment, ABI≤0.9 or prior revascularization was associated with a three-fold odds of aortic plaque (p=0.0083). Plaque volume significantly increased with decreasing ABI in multivariable-adjusted analyses (p<0.0001). In this free-living population, associations of WMAs with aortic plaque burden and clinical measures of PAD were attenuated after adjustment for coronary heart disease risk factors. Aortic plaque volume and ABI remained strongly negatively correlated after multivariable adjustment. Our findings suggest that the association between coronary heart disease and non-coronary atherosclerosis is explained by cardiovascular risk factors. Aortic atherosclerosis and PAD remain strongly associated after multivariable adjustment suggesting shared mechanisms beyond those captured by traditional risk factors. PMID:21708875

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.

The relationship between single and two-dimensional indices of left ventricular size using hemodynamic transesophageal echocardiography in trauma and burn patients.

PubMed

Younan, Duraid; Beasley, T Mark; Pigott, David C; Gibson, C Blayke; Gullett, John P; Richey, Jeffrey; Pittet, Jean-Francois; Zaky, Ahmed

2017-10-11

Conventional echocardiographic technique for assessment of volume status and cardiac contractility utilizes left ventricular end-diastolic area (LVEDA) and fractional area of change (FAC), respectively. Our goal was to find a technically reliable yet faster technique to evaluate volume status and contractility by measuring left ventricular end-diastolic diameter (LVEDD) and fractional shortening (FS) in a cohort of mechanically ventilated trauma and burn patients using hemodynamic transesophageal echocardiographic (hTEE) monitoring. Retrospective chart review performed at trauma/burn intensive care unit (TBICU). Data on 88 mechanically ventilated surgical intensive care patients cared for between July 2013 and July 2015 were reviewed. Initial measurements of LVEDA, left ventricular end-systolic area (LVESA) and FAC were collected. Post-processing left ventricular end-systolic (LVESD) and end-diastolic diameters (LVEDD) were measured and fractional shortening (FS) was calculated. Two orthogonal measurements of LV diameter were obtained in transverse (Tr) and posteroanterior (PA) orientation. There was a significant correlation between transverse and posteroanterior left ventricular diameter measurements in both systole and diastole. In systole, r = 0.92, p < 0.01 for LVESD-Tr (mean 23.47 mm, SD ± 6.77) and LVESD-PA (mean 24.84 mm, SD = 8.23). In diastole, r = 0.80, p < 0.01 for LVEDD-Tr (mean 37.60 mm, SD ± 6.45), and LVEDD-PA diameters (mean 42.24 mm, SD ± 7.97). Left ventricular area (LVEDA) also significantly correlated with left ventricular diameter LVEDD-Tr (r = 0.84, p < 0.01) and LVEDD-PA (r = 0.90, p < 0.01). Both transverse and PA measurements of fractional shortening were significantly (p < 0.0001) and similarly correlated with systolic function as measured by FAC. Bland-Altman analyses also indicated that the assessment of fractional shortening using left ventricular posteroanterior diameter measurement shows agreement with FAC. Left ventricular diameter measurements are a reliable and technically feasible alternative to left ventricular area measurements in the assessment of cardiac filling and systolic function.

Left ventricular remodelling in chronic primary mitral regurgitation: implications for medical therapy.

PubMed

McCutcheon, Keir; Manga, Pravin

Surgical repair or replacement of the mitral valve is currently the only recommended therapy for severe primary mitral regurgitation. The chronic elevation of wall stress caused by the resulting volume overload leads to structural remodelling of the muscular, vascular and extracellular matrix components of the myocardium. These changes are initially compensatory but in the long term have detrimental effects, which ultimately result in heart failure. Understanding the changes that occur in the myocardium due to volume overload at the molecular and cellular level may lead to medical interventions, which potentially could delay or prevent the adverse left ventricular remodelling associated with primary mitral regurgitation. The pathophysiological changes involved in left ventricular remodelling in response to chronic primary mitral regurgitation and the evidence for potential medical therapy, in particular beta-adrenergic blockers, are the focus of this review.

Evaluation of changes in left ventricular structure and function in hypertensive patients with coronary artery disease after PCI using real-time three-dimensional echocardiography.

PubMed

Meng, Yanhong; Zong, Ling; Zhang, Ziteng; Han, Youdong; Wang, Yanhui

2018-02-01

We aimed to evaluate the changes in left ventricular structure and function in hypertensive patients with coronary artery disease before and after percutaneous coronary intervention (PCI) using real-time three-dimensional echocardiography. Two hundred and eighty hypertensive patients with coronary artery disease undergoing PCI and 120 cases who did not receive PCI in our hospital were selected as the subjects of our study. All patients were administered with routine antiplatelet, anticoagulant, lipid-lowering, antihypertensive, dilating coronary artery and other medications. The left ventricular systolic function and systolic synchrony index changes before and after subjects were treated by PCI were analyzed using three-dimensional echocardiography. At 2 days before surgery, there were no significant differences in the left ventricular end-diastolic volume, left ventricular end-systolic volume (LVESV) and ejection fraction (EF) between the two patient groups (P>0.05). At 3 months and 9 months, the two key time points after PCI, the LVESV level in the PCI group was distinctly decreased, while EF was significantly increased (P<0.05). In addition, before treatment, there were no significant differences in the parameters of time from the corresponding segment of the myocardium to the minimal systolic volume in two patient groups, such as Tmsv-16SD, Tmsv-16Dif, Tmsv-12SD, Tmsv-12Dif, Tmsv-6SD and Tmsv-6Dif (P>0.05); however, the parameters of time from the corresponding segment of the myocardium to the minimal systolic volume in patients in the PCI group were significantly reduced at 3 and 9 months after surgery (P<0.05). Three-dimensional echocardiography can evaluate the critical parameters in the prognosis of hypertensive patients with coronary artery disease after PCI accurately and in real-time, which may play a significant role.

Evidence for increased cardiac compliance during exposure to simulated microgravity

NASA Technical Reports Server (NTRS)

Koenig, S. C.; Convertino, V. A.; Fanton, J. W.; Reister, C. A.; Gaffney, F. A.; Ludwig, D. A.; Krotov, V. P.; Trambovetsky, E. V.; Latham, R. D.

1998-01-01

We measured hemodynamic responses during 4 days of head-down tilt (HDT) and during graded lower body negative pressure (LBNP) in invasively instrumented rhesus monkeys to test the hypotheses that exposure to simulated microgravity increases cardiac compliance and that decreased stroke volume, cardiac output, and orthostatic tolerance are associated with reduced left ventricular peak dP/dt. Six monkeys underwent two 4-day (96 h) experimental conditions separated by 9 days of ambulatory activities in a crossover counterbalance design: 1) continuous exposure to 10 degrees HDT and 2) approximately 12-14 h per day of 80 degrees head-up tilt and 10-12 h supine (control condition). Each animal underwent measurements of central venous pressure (CVP), left ventricular and aortic pressures, stroke volume, esophageal pressure (EsP), plasma volume, alpha1- and beta1-adrenergic responsiveness, and tolerance to LBNP. HDT induced a hypovolemic and hypoadrenergic state with reduced LBNP tolerance compared with the control condition. Decreased LBNP tolerance with HDT was associated with reduced stroke volume, cardiac output, and peak dP/dt. Compared with the control condition, a 34% reduction in CVP (P = 0.010) and no change in left ventricular end-diastolic area during HDT was associated with increased ventricular compliance (P = 0.0053). Increased cardiac compliance could not be explained by reduced intrathoracic pressure since EsP was unaltered by HDT. Our data provide the first direct evidence that increased cardiac compliance was associated with headward fluid shifts similar to those induced by exposure to spaceflight and that reduced orthostatic tolerance was associated with lower cardiac contractility.

Cardiac dimensions and function in female handball players.

PubMed

Malmgren, A; Dencker, M; Stagmo, M; Gudmundsson, P

2015-04-01

Long-term intensive endurance training leads to increased left ventricular mass and increased left ventricular end-diastolic and left atrial end-systolic diameters. Different types of sports tend to give rise to distinct morphological forms of the athlete's heart. However, the sport-specific aspects have not been fully investigated in female athletes. The purpose of the present study was to investigate differences in left and right cardiac dimensions, cardiac volumes, and systolic and diastolic function in elite female handball players compared to sedentary controls. A cross-sectional study of 33 elite female handball players was compared to 33 matched sedentary controls. Mean age was 21.5±2 years. The subjects underwent echocardiography examinations, both 2-dimensional (2DE) and 3-dimensional (3DE). Cardiac dimensions and volumes were quantified using M-mode, 2DE and 3DE. Systolic and diastolic left ventricular functions were also evaluated. All cardiac dimensions and volumes were adjusted for body surface area (BSA). Left atrium and left ventricle volumes were significantly (P<0.001) larger in elite female handball players compared with sedentary controls. Even right atrium area as well as right ventricular end-diastolic and end-systolic area were significantly (P<0.001) larger in elite female handball players. Significant differences were observed in three out of five systolic parameters. Most diastolic function parameters did not differ between the two groups. The findings from the present study suggest that similar cardiac remodeling takes place in elite female handball players as it does in athletes pursuing endurance or team game sports.

Intraspecific individual variation of temperature tolerance associated with oxygen demand in the European sea bass (Dicentrarchus labrax)

PubMed Central

Ozolina, Karlina; Shiels, Holly A; Ollivier, Hélène; Claireaux, Guy

2016-01-01

Abstract The European sea bass (Dicentrarchus labrax) is an economically important fish native to the Mediterranean and Northern Atlantic. Its complex life cycle involves many migrations through temperature gradients that affect the energetic demands of swimming. Previous studies have shown large intraspecific variation in swimming performance and temperature tolerance, which could include deleterious and advantageous traits under the evolutionary pressure of climate change. However, little is known of the underlying determinants of this individual variation. We investigated individual variation in temperature tolerance in 30 sea bass by exposing them to a warm temperature challenge test. The eight most temperature-tolerant and eight most temperature-sensitive fish were then studied further to determine maximal swimming speed (UCAT), aerobic scope and post-exercise oxygen consumption. Finally, ventricular contractility in each group was determined using isometric muscle preparations. The temperature-tolerant fish showed lower resting oxygen consumption rates, possessed larger hearts and initially recovered from exhaustive exercise faster than the temperature-sensitive fish. Thus, whole-animal temperature tolerance was associated with important performance traits. However, the temperature-tolerant fish also demonstrated poorer maximal swimming capacity (i.e. lower UCAT) than their temperature-sensitive counterparts, which may indicate a trade-off between temperature tolerance and swimming performance. Interestingly, the larger relative ventricular mass of the temperature-tolerant fish did not equate to greater ventricular contractility, suggesting that larger stroke volumes, rather than greater contractile strength, may be associated with thermal tolerance in this species. PMID:27382468

Intraspecific individual variation of temperature tolerance associated with oxygen demand in the European sea bass (Dicentrarchus labrax).

PubMed

Ozolina, Karlina; Shiels, Holly A; Ollivier, Hélène; Claireaux, Guy

2016-01-01

The European sea bass (Dicentrarchus labrax) is an economically important fish native to the Mediterranean and Northern Atlantic. Its complex life cycle involves many migrations through temperature gradients that affect the energetic demands of swimming. Previous studies have shown large intraspecific variation in swimming performance and temperature tolerance, which could include deleterious and advantageous traits under the evolutionary pressure of climate change. However, little is known of the underlying determinants of this individual variation. We investigated individual variation in temperature tolerance in 30 sea bass by exposing them to a warm temperature challenge test. The eight most temperature-tolerant and eight most temperature-sensitive fish were then studied further to determine maximal swimming speed (U CAT), aerobic scope and post-exercise oxygen consumption. Finally, ventricular contractility in each group was determined using isometric muscle preparations. The temperature-tolerant fish showed lower resting oxygen consumption rates, possessed larger hearts and initially recovered from exhaustive exercise faster than the temperature-sensitive fish. Thus, whole-animal temperature tolerance was associated with important performance traits. However, the temperature-tolerant fish also demonstrated poorer maximal swimming capacity (i.e. lower U CAT) than their temperature-sensitive counterparts, which may indicate a trade-off between temperature tolerance and swimming performance. Interestingly, the larger relative ventricular mass of the temperature-tolerant fish did not equate to greater ventricular contractility, suggesting that larger stroke volumes, rather than greater contractile strength, may be associated with thermal tolerance in this species.

Determinants of the development of mitral regurgitation in pacing-induced heart failure.

PubMed

Takagaki, Masami; McCarthy, Patrick M; Goormastic, Marlene; Ochiai, Yoshie; Doi, Kazuyoshi; Kopcak, Michael W; Tabata, Tomotsugu; Cardon, Lisa A; Thomas, James D; Fukamachi, Kiyotaka

2003-01-01

The pacing-induced heart failure model provides an opportunity to assess the structural and functional determinants of mitral regurgitation (MR) in dilated cardiomyopathy. This study aimed to evaluate MR to better understand the multitude of factors contributing to its development. Heart failure was induced by rapid ventricular pacing (230 beats/min) in 40 mongrel dogs. Left ventricular (LV) size and MR were evaluated echocardiographically. LV contractility was analyzed using a conductance catheter. MR increased to mild in 12 animals (regurgitant orifice area, 0.06+/-0.05 cm(2)), moderate in 15 (0.14+/-0.07 cm(2)), and severe in 13 (0.34+/-0.16 cm(2)). The grade of MR had an inverse relationships with E(max) (the slope of the end-systolic pressure-volume relationship, p<0.01) and dE/dt (the slope of the maximum rate of change of pressure-end-diastolic volume [V(ED)] relationship, p<0.01) and positive relationships with V(ED) and end-diastolic cross-sectional areas and lengths (p<0.05) by univariate analysis. The dE/dt had an independently significant (p<0.01) relationship by multivariable logistic regression. Many factors influence the development of MR and because of its similarity to the clinical situation, this model can be used to investigate MR and heart failure, as well as new surgical therapies.

Adiponectin downregulation is associated with volume overload-induced myocyte dysfunction in rats

PubMed Central

Wang, Li-li; Miller, Dori; Wanders, Desiree; Nanayakkara, Gayani; Amin, Rajesh; Judd, Robert; Morrison, Edward E; Zhong, Ju-ming

2016-01-01

Aim: Adiponectin has been reported to exert protective effects during pathological ventricular remodeling, but the role of adiponectin in volume overload-induced heart failure remains unclear. In this study we investigated the effect of adiponectin on cardiac myocyte contractile dysfunction following volume overload in rats. Methods: Volume overload was surgically induced in rats by infrarenal aorta-vena cava fistula. The rats were intravenously administered adenoviral adiponectin at 2-, 6- and 9-weeks following fistula. The protein expression of adiponectin, adiponectin receptors (AdipoR1/R2 and T-cadherin) and AMPK activity were measured using Western blot analyses. Isolated ventricular myocytes were prepared at 12 weeks post-fistula to examine the contractile performance of myocytes and intracellular Ca2+ transient. Results: A-V fistula resulted in significant reductions in serum and myocardial adiponectin levels, myocardial adiponectin receptor (AdipoR1/R2 and T-cadherin) levels, as well as myocardial AMPK activity. Consistent with these changes, the isolated myocytes exhibited significant depression in cell shortening and intracellular Ca2+ transient. Administration of adenoviral adiponectin significantly increased serum adiponectin levels and prevented myocyte contractile dysfunction in fistula rats. Furthermore, pretreatment of isolated myocytes with recombinant adiponectin (2.5 μg/mL) significantly improved their contractile performance in fistula rats, but had no effects in control or adenoviral adiponectin-administered rats. Conclusion: These results demonstrate a positive correlation between adiponectin downregulation and volume overload-induced ventricular remodeling. Adiponectin plays a protective role in volume overload-induced heart failure. PMID:26616727

Percent Emphysema and Right Ventricular Structure and Function

PubMed Central

Grau, Maria; Lima, Joao A.; Hoffman, Eric A.; Bluemke, David A.; Carr, J. Jeffrey; Chahal, Harjit; Enright, Paul L; Jain, Aditya; Prince, Martin R.; Kawut, Steven M.

2013-01-01

Background: Severe COPD can lead to cor pulmonale and emphysema and is associated with impaired left ventricular (LV) filling. We evaluated whether emphysema and airflow obstruction would be associated with changes in right ventricular (RV) structure and function and whether these associations would differ by smoking status. Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) performed cardiac MRI on 5,098 participants without clinical cardiovascular disease aged 45 to 84 years. RV and emphysema measures were available for 4,188 participants. Percent emphysema was defined as the percentage of voxels below −910 Hounsfield units in the lung windows on cardiac CT scans. Generalized additive models were used to control for confounders and adjust for respective LV parameters. Results: Participants consisted of 13% current smokers, 36% former smokers, and 52% never smokers. Percent emphysema was inversely associated with RV end-diastolic volume, stroke volume, cardiac output, and mass prior to adjustment for LV measures. After adjustment for LV end-diastolic volume, greater percent emphysema was associated with greater RV end-diastolic volume (+1.5 mL, P = .03) among current smokers, smaller RV end-diastolic volume (−0.8 mL, P = .02) among former smokers, and similar changes among never smokers. Conclusions: Percent emphysema was associated with smaller RV volumes and lower mass. The relationship of emphysema to cardiac function is complex but likely involves increased pulmonary vascular resistance, predominantly with reduced cardiac output, pulmonary hyperinflation, and accelerated cardiopulmonary aging. PMID:23450302

Quantitative computed tomography of pulmonary emphysema and ventricular function in chronic obstructive pulmonary disease patients with pulmonary hypertension.

PubMed

Huang, Yu-Sen; Hsu, Hsao-Hsun; Chen, Jo-Yu; Tai, Mei-Hwa; Jaw, Fu-Shan; Chang, Yeun-Chung

2014-01-01

This study strived to evaluate the relationship between degree of pulmonary emphysema and cardiac ventricular function in chronic obstructive pulmonary disease (COPD) patients with pulmonary hypertension (PH) using electrocardiographic-gated multidetector computed tomography (CT). Lung transplantation candidates with the diagnosis of COPD and PH were chosen for the study population, and a total of 15 patients were included. The extent of emphysema is defined as the percentage of voxels below -910 Hounsfield units in the lung windows in whole lung CT without intravenous contrast. Heart function parameters were measured by electrocardiographic-gated CT angiography. Linear regression analysis was conducted to examine the associations between percent emphysema and heart function indicators. Significant correlations were found between percent emphysema and right ventricular (RV) measurements, including RV end-diastolic volume (R(2) = 0.340, p = 0.023), RV stroke volume (R(2) = 0.406, p = 0.011), and RV cardiac output (R(2) = 0.382, p = 0.014); the correlations between percent emphysema and left ventricular function indicators were not observed. The study revealed that percent emphysema is correlated with RV dysfunction among COPD patients with PH. Based on our findings, percent emphysema can be considered for use as an indicator to predict the severity of right ventricular dysfunction among COPD patients.

Investigating structural brain changes of dehydration using voxel-based morphometry.

PubMed

Streitbürger, Daniel-Paolo; Möller, Harald E; Tittgemeyer, Marc; Hund-Georgiadis, Margret; Schroeter, Matthias L; Mueller, Karsten

2012-01-01

Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T(1)-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The datasets were analyzed using voxel-based morphometry (VBM), a widely used voxel-wise statistical analysis tool, FreeSurfer, a fully automated volumetric segmentation measure, and SIENAr a longitudinal brain-change detection algorithm. A significant decrease of GM and WM volume associated with dehydration was found in various brain regions, most prominently, in temporal and sub-gyral parietal areas, in the left inferior orbito-frontal region, and in the extra-nuclear region. Moreover, we found consistent increases in CSF, that is, an expansion of the ventricular system affecting both lateral ventricles, the third, and the fourth ventricle. Similar degrees of shrinkage in WM volume and increase of the ventricular system have been reported in studies of mild cognitive impairment or Alzheimer's disease during disease progression. Based on these findings, a potential confound in GM and WM or ventricular volume studies due to the subjects' hydration state cannot be excluded and should be appropriately addressed in morphometric studies of the brain.

Investigating Structural Brain Changes of Dehydration Using Voxel-Based Morphometry

PubMed Central

Streitbürger, Daniel-Paolo; Möller, Harald E.; Tittgemeyer, Marc; Hund-Georgiadis, Margret; Schroeter, Matthias L.; Mueller, Karsten

2012-01-01

Dehydration can affect the volume of brain structures, which might imply a confound in volumetric and morphometric studies of normal or diseased brain. Six young, healthy volunteers were repeatedly investigated using three-dimensional T 1-weighted magnetic resonance imaging during states of normal hydration, hyperhydration, and dehydration to assess volume changes in gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF). The datasets were analyzed using voxel-based morphometry (VBM), a widely used voxel-wise statistical analysis tool, FreeSurfer, a fully automated volumetric segmentation measure, and SIENAr a longitudinal brain-change detection algorithm. A significant decrease of GM and WM volume associated with dehydration was found in various brain regions, most prominently, in temporal and sub-gyral parietal areas, in the left inferior orbito-frontal region, and in the extra-nuclear region. Moreover, we found consistent increases in CSF, that is, an expansion of the ventricular system affecting both lateral ventricles, the third, and the fourth ventricle. Similar degrees of shrinkage in WM volume and increase of the ventricular system have been reported in studies of mild cognitive impairment or Alzheime s disease during disease progression. Based on these findings, a potential confound in GM and WM or ventricular volume studies due to the subjects’ hydration state cannot be excluded and should be appropriately addressed in morphometric studies of the brain. PMID:22952926

Right ventricular volumes assessed by echocardiographic three-dimensional knowledge-based reconstruction compared with magnetic resonance imaging in a clinical setting.

PubMed

Neukamm, Christian; Try, Kirsti; Norgård, Gunnar; Brun, Henrik

2014-01-01

A technique that uses two-dimensional images to create a knowledge-based, three-dimensional model was tested and compared to magnetic resonance imaging. Measurement of right ventricular volumes and function is important in the follow-up of patients after pulmonary valve replacement. Magnetic resonance imaging is the gold standard for volumetric assessment. Echocardiographic methods have been validated and are attractive alternatives. Thirty patients with tetralogy of Fallot (25 ± 14 years) after pulmonary valve replacement were examined. Magnetic resonance imaging volumetric measurements and echocardiography-based three-dimensional reconstruction were performed. End-diastolic volume, end-systolic volume, and ejection fraction were measured, and the results were compared. Magnetic resonance imaging measurements gave coefficient of variation in the intraobserver study of 3.5, 4.6, and 5.3 and in the interobserver study of 3.6, 5.9, and 6.7 for end-diastolic volume, end-systolic volume, and ejection fraction, respectively. Echocardiographic three-dimensional reconstruction was highly feasible (97%). In the intraobserver study, the corresponding values were 6.0, 7.0, and 8.9 and in the interobserver study 7.4, 10.8, and 13.4. In comparison of the methods, correlations with magnetic resonance imaging were r = 0.91, 0.91, and 0.38, and the corresponding coefficient of variations were 9.4, 10.8, and 14.7. Echocardiography derived volumes (mL/m(2)) were significantly higher than magnetic resonance imaging volumes in end-diastolic volume 13.7 ± 25.6 and in end-systolic volume 9.1 ± 17.0 (both P < .05). The knowledge-based three-dimensional right ventricular volume method was highly feasible. Intra and interobserver variabilities were satisfactory. Agreement with magnetic resonance imaging measurements for volumes was reasonable but unsatisfactory for ejection fraction. Knowledge-based reconstruction may replace magnetic resonance imaging measurements for serial follow-up, whereas magnetic resonance imaging should be used for surgical decision making.

Two-Dimensional Echocardiography Estimates of Fetal Ventricular Mass throughout Gestation.

PubMed

Aye, Christina Y L; Lewandowski, Adam James; Ohuma, Eric O; Upton, Ross; Packham, Alice; Kenworthy, Yvonne; Roseman, Fenella; Norris, Tess; Molloholli, Malid; Wanyonyi, Sikolia; Papageorghiou, Aris T; Leeson, Paul

2017-08-12

Two-dimensional (2D) ultrasound quality has improved in recent years. Quantification of cardiac dimensions is important to screen and monitor certain fetal conditions. We assessed the feasibility and reproducibility of fetal ventricular measures using 2D echocardiography, reported normal ranges in our cohort, and compared estimates to other modalities. Mass and end-diastolic volume were estimated by manual contouring in the four-chamber view using TomTec Image Arena 4.6 in end diastole. Nomograms were created from smoothed centiles of measures, constructed using fractional polynomials after log transformation. The results were compared to those of previous studies using other modalities. A total of 294 scans from 146 fetuses from 15+0 to 41+6 weeks of gestation were included. Seven percent of scans were unanalysable and intraobserver variability was good (intraclass correlation coefficients for left and right ventricular mass 0.97 [0.87-0.99] and 0.99 [0.95-1.0], respectively). Mass and volume increased exponentially, showing good agreement with 3D mass estimates up to 28 weeks of gestation, after which our measurements were in better agreement with neonatal cardiac magnetic resonance imaging. There was good agreement with 4D volume estimates for the left ventricle. Current state-of-the-art 2D echocardiography platforms provide accurate, feasible, and reproducible fetal ventricular measures across gestation, and in certain circumstances may be the modality of choice. © 2017 S. Karger AG, Basel.

Extracellular Volume Detects Amyloidotic Cardiomyopathy and Correlates With Neurological Impairment in Transthyretin-familial Amyloidosis.

PubMed

Gallego-Delgado, María; González-López, Esther; Muñoz-Beamud, Francisco; Buades, Juan; Galán, Lucía; Muñoz-Blanco, Jose Luis; Sánchez-González, Javier; Ibáñez, Borja; Mirelis, Jesus G; García-Pavía, Pablo

2016-10-01

Cardiac involvement determines prognosis and treatment options in transthyretin-familial amyloidosis. Cardiac magnetic resonance T 1 mapping techniques are useful to assess myocardial extracellular volume. This study hypothesized that myocardial extracellular volume allows identification of amyloidotic cardiomyopathy and correlates with the degree of neurological impairment in transthyretin-familial amyloidosis. A total of 31 transthyretin-familial amyloidosis patients (19 mean age, 49 ± 12 years; 26 with the Val30Met mutation) underwent a T 1 mapping cardiac magnetic resonance study and a neurological evaluation with Neuropathy Impairment Score of the Lower Limb score, Norfolk Quality of Life questionnaire, and Karnofsky index. Five patients had cardiac amyloidosis (all confirmed by 99m Tc-DPD scintigraphy). Mean extracellular volume was increased in patients with cardiac amyloidosis (0.490 ± 0.131 vs 0.289 ± 0.035; P = .026). Extracellular volume correlated with age (R = 0.467; P = .008), N-terminal pro-B-type natriuretic peptide (R S = 0.846; P < .001), maximum wall thickness (R = 0.621; P < .001), left ventricular mass index (R = 0.685; P < .001), left ventricular ejection fraction (R = -0.378; P = .036), Neuropathy Impairment Score of the Lower Limb (R S = 0.604; P = .001), Norfolk Quality of Life questionnaire (R S = 0.529; P = .003) and Karnofsky index (R S = -0.517; P = .004). A cutoff value of extracellular volume of 0.357 was diagnostic of cardiac amyloidosis with 100% sensitivity and specificity (P < .001). Extracellular volume and N-terminal pro-B-type natriuretic peptide were the only cardiac parameters that significantly correlated with neurologic scores. Extracellular volume quantification allows identification of cardiac amyloidosis and correlates with the degree of neurological impairment in transthyretin-familial amyloidosis. This noninvasive technique could be a useful tool for early diagnosis of cardiac amyloidosis and to track cardiac and extracardiac amyloid disease. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

SU-E-QI-12: Morphometry Based Measurements of the Structural Response to Whole Brain Radiation

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

Fuentes, D; Castillo, R; Castillo, E

2014-06-15

Purpose: Although state of the art radiation therapy techniques for treating intracranial malignancies have eliminated acute brain injury, cognitive impairment occurs in 50–90% of patients who survive >6mo post irradiation. Quantitative characterization of therapy response is needed to facilitate therapeutic strategies to minimize radiation induced cognitive impairment [1]. Deformation based morphometry techniques [2, 3] are presented as a quantitative imaging biomarker of therapy response in patients receiving whole brain radiation for treating medulloblastoma. Methods: Post-irradiation magnetic resonance imaging (MRI) data sets were retrospectively analyzed in N=15 patients, >60 MR image datasets. As seen in Fig 1(a), volume changes at multiplemore » time points post-irradiation were quantitatively measured in the cerebrum and ventricles with respect to pre-irradiation MRI. A high resolution image Template, was registered to the pre-irradiation MRI of each patient to create a brain atlas for the cerebrum, cerebellum, and ventricles. Skull stripped images for each patient were registered to the initial pre-treatment scan. Average volume changes in the labeled regions were measured using the determinant of the displacement field Jacobian. Results: Longitudinal measurements, Fig 1(b-c), show a negative correlation p=.06, of the cerebral volume change with the time interval from irradiation. A corresponding positive correlation, p=.01, between ventricular volume change and time interval from irradiation is seen. One sample t-test for correlations were computed using a Spearman method. An average decrease in cerebral volume, p=.08, and increase in ventricular volume, p<.001, was observed. The radiation dose was seen directly proportional to the induced volume changes in the cerebrum, r=−.44, p<.001, Fig 1(d). Conclusion: Results indicate that morphometric monitoring of brain tissue volume changes may potentially be used to quantitatively assess toxicity and response to radiation and may provide insight in developing new therapeutic approaches and monitoring efficacy.« less

Relation of N-Terminal Pro-B-Type Natriuretic Peptide and Left Ventricular Diastolic Function to Exercise Tolerance in Patients With Significant Valvular Heart Disease and Normal Left Ventricular Systolic Function.

PubMed

Hwang, Ji-Won; Park, Sung-Ji; Cho, Eun Jeong; Kim, Eun Kyoung; Lee, Ga Yeon; Chang, Sung-A; Choi, Jin-Oh; Lee, Sang-Chol; Park, Seung Woo

2017-06-01

An association between N-terminal prohormone brain natriuretic peptide (NT-proBNP) and exercise tolerance in patients with valvular heart disease (VHD) has been suggested; however, there are few data available regarding this relation. The aim of this study is to evaluate the correlation between exercise tolerance and NT-proBNP in patients with asymptomatic or mildly symptomatic significant VHD and normal left ventricular ejection fraction (LV EF). A total of 96 patients with asymptomatic or mildly symptomatic VHD and normal LV EF (≥50%) underwent cardiopulmonary exercise echocardiography. NT-proBNP levels were determined at baseline and after exercise in 3 hours. Patients were divided in 2 groups based on lower (<26 ml/kg/min, n = 47) or higher (≥26 ml/kg/min, n = 49) peak oxygen consumption (VO 2 ) as a representation of exercise tolerance. In the 2 groups, after adjusting for age and gender, the NT-proBNP level after exercise in 3 hours, left atrial volume index before exercise, right ventricular systolic pressure before exercise, E velocity after exercise, and E/e' ratio after exercise varied significantly. In addition, peak VO 2 was inversely related to NT-proBNP before (r = -0.352, p <0.001) and after exercise (r = -0.351, p <0.001). The NT-proBNP level before exercise was directly related to the left atrial volume index, E/e' ratio, and right ventricular systolic pressure before and after exercise. NT-proBNP after exercise was also directly related to the same parameters. NT-proBNP levels both before and after exercise were higher in the group with lower exercise tolerance. In conclusion, through the correlation among exercise tolerance, NT-proBNP, and parameters of diastolic dysfunction, we demonstrated that diastolic dysfunction and NT-proBNP could predict exercise tolerance in patients with significant VHD and normal LV EF. Copyright © 2017 Elsevier Inc. All rights reserved.

Leaving Moderate Tricuspid Valve Regurgitation Alone at the Time of Pulmonary Valve Replacement: A Worthwhile Approach.

PubMed

Kogon, Brian; Mori, Makoto; Alsoufi, Bahaaldin; Kanter, Kirk; Oster, Matt

2015-06-01

Pulmonary valve disruption in patients with tetralogy of Fallot and congenital pulmonary stenosis often results in pulmonary insufficiency, right ventricular dilation, and tricuspid valve regurgitation. Management of functional tricuspid regurgitation at the time of subsequent pulmonary valve replacement remains controversial. Our aims were to (1) analyze tricuspid valve function after pulmonary valve replacement through midterm follow-up and (2) determine the benefits, if any, of concomitant tricuspid annuloplasty. Thirty-five patients with tetralogy of Fallot or congenital pulmonary stenosis were analyzed. All patients had been palliated in childhood by disrupting the pulmonary valve, and all patients had at least moderate tricuspid valve regurgitation at the time of subsequent pulmonary valve replacement. Preoperative and serial postoperative echocardiograms were analyzed. Pulmonary and tricuspid regurgitation, along with right ventricular dilation and dysfunction were scored as 0 (none), 1 (mild), 2 (moderate), and 3 (severe). Right ventricular volume and area were also calculated. Comparisons were made between patients who underwent pulmonary valve replacement alone and those who underwent concomitant tricuspid valve annuloplasty. At 1 month after pulmonary valve replacement, there were significant reductions in pulmonary valve regurgitation (mean 3 vs 0.39, p < 0.0001), tricuspid valve regurgitation (mean 2.33 vs 1.3, p < 0.0001), and in right ventricular dilation, volume, and area. There was no difference in the degree of tricuspid regurgitation 1 month postoperatively between patients who underwent concomitant tricuspid annuloplasty and those who underwent pulmonary valve replacement alone (mean 1.31 vs 1.29, p = 0.81). However, at latest follow-up (mean 7.0 ± 2.8 years), the degree of tricuspid regurgitation was significantly higher in the concomitant annuloplasty group (mean 1.87 vs 1.12, p = 0.005). In patients with at least moderate tricuspid valve regurgitation, significant improvement in tricuspid valve function and right ventricular size occurs in the first postoperative month after pulmonary valve replacement, irrespective of concomitant tricuspid valve annuloplasty. The tricuspid valve appears to function better over the midterm if annuloplasty is not performed. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Successful Feasibility Human Trial of a New Self-Expandable Percutaneous Pulmonary Valve (Pulsta Valve) Implantation Using Knitted Nitinol Wire Backbone and Trileaflet α-Gal-Free Porcine Pericardial Valve in the Native Right Ventricular Outflow Tract.

PubMed

Kim, Gi Beom; Song, Mi Kyoung; Bae, Eun Jung; Park, Eun-Ah; Lee, Whal; Lim, Hong-Gook; Kim, Yong Jin

2018-06-01

Self-expandable percutaneous pulmonary valve implantation (PPVI) for native right ventricular outflow tract lesions is still in the clinical trial phase. The aim of this study is to present the result of feasibility study of a novel self-expandable knitted nitinol wire stent mounted with a treated trileaflet α-Gal-free porcine pericardial valve for PPVI. A feasibility study using Pulsta valve (TaeWoong Medical Co, Gyeonggi-do, South Korea) was designed for patients with severe pulmonary regurgitation in the native right ventricular outflow tract, and 6-month follow-up outcomes were reviewed. Ten tetralogy of Fallot patients were enrolled. Before PPVI, severe pulmonary regurgitation (mean pulmonary regurgitation fraction, 45.5%±7.2%; range, 34.9%-56%) and enlarged right ventricular volume (mean indexed right ventricular end-diastolic volume, 176.7±14.3 mL/m 2 ; range, 158.9-205.9 mL/m 2 ) were present. The median age at PPVI was 21.7±6.5 years (range, 13-36 years). Five patients were successfully implanted with 28 mm and the other 5 with 26 mm valves loaded on the 18F delivery cable. No significant periprocedural complications were noted in any patient. At the 6-month follow-up, indexed right ventricular end-diastolic volume was dramatically decreased to 126.3±20.3 mL/m 2 (range, 99-164.2 mL/m 2 ), and the mean value of peak instantaneous pressure gradient between the right ventricle and the pulmonary artery decreased from 6.8±3.5 mm Hg (range, 2-12 mm Hg) before PPVI to 5.7±6.7 mm Hg (range, 2-12 mm Hg) without significant pulmonary regurgitation. There was no adverse event associated with the valve. A feasibility study of the Pulsta valve for native right ventricular outflow tract lesions was completed successfully with planned Pulsta valve implantation and demonstrated good short-term effectiveness without serious adverse events. URL: https://www.clinicaltrials.gov. Unique identifier: NCT02555319. © 2018 American Heart Association, Inc.

Titin isoform switching is a major cardiac adaptive response in hibernating grizzly bears.

PubMed

Nelson, O Lynne; Robbins, Charles T; Wu, Yiming; Granzier, Henk

2008-07-01

The hibernation phenomenon captures biological as well as clinical interests to understand how organs adapt. Here we studied how hibernating grizzly bears (Ursus arctos horribilis) tolerate extremely low heart rates without developing cardiac chamber dilation. We evaluated cardiac filling function in unanesthetized grizzly bears by echocardiography during the active and hibernating period. Because both collagen and titin are involved in altering diastolic function, we investigated both in the myocardium of active and hibernating grizzly bears. Heart rates were reduced from 84 beats/min in active bears to 19 beats/min in hibernating bears. Diastolic volume, stroke volume, and left ventricular ejection fraction were not different. However, left ventricular muscle mass was significantly lower (300 +/- 12 compared with 402 +/- 14 g; P = 0.003) in the hibernating bears, and as a result the diastolic volume-to-left ventricular muscle mass ratio was significantly greater. Early ventricular filling deceleration times (106.4 +/- 14 compared with 143.2 +/- 20 ms; P = 0.002) were shorter during hibernation, suggesting increased ventricular stiffness. Restrictive pulmonary venous flow patterns supported this conclusion. Collagen type I and III comparisons did not reveal differences between the two groups of bears. In contrast, the expression of titin was altered by a significant upregulation of the stiffer N2B isoform at the expense of the more compliant N2BA isoform. The mean ratio of N2BA to N2B titin was 0.73 +/- 0.07 in the active bears and decreased to 0.42 +/- 0.03 (P = 0.006) in the hibernating bears. The upregulation of stiff N2B cardiac titin is a likely explanation for the increased ventricular stiffness that was revealed by echocardiography, and we propose that it plays a role in preventing chamber dilation in hibernating grizzly bears. Thus our work identified changes in the alternative splicing of cardiac titin as a major adaptive response in hibernating grizzly bears.

Analysis of transthoracic echocardiographic data in major vascular surgery from a prospective randomised trial comparing sevoflurane and fentanyl with propofol and remifentanil anaesthesia.

PubMed

Lindholm, E E; Aune, E; Frøland, G; Kirkebøen, K A; Otterstad, J E

2014-06-01

The aim of this study was to define pre-operative echocardiographic data and explore if postoperative indices of cardiac function after open abdominal aortic surgery were affected by the anaesthetic regimen. We hypothesised that volatile anaesthesia would improve indices of cardiac function compared with total intravenous anaesthesia. Transthoracic echocardiography was performed pre-operatively in 78 patients randomly assigned to volatile anaesthesia and 76 to total intravenous anaesthesia, and compared with postoperative data. Pre-operatively, 16 patients (10%) had left ventricular ejection fraction < 46%. In 138 patients with normal left ventricular ejection fraction, 5/8 (62%) with left ventricular dilatation and 41/130 (33%) without left ventricular dilatation had evidence of left ventricular diastolic dysfunction (p < 0.001). Compared with pre-operative findings, significant increases in left ventricular end-diastolic volume, left atrial maximal volume, cardiac output, velocity of early mitral flow and early myocardial relaxation occurred postoperatively (all p < 0.001). The ratio of the velocity of early mitral flow to early myocardial relaxation remained unchanged. There were no significant differences in postoperative echocardiographic findings between patients anaesthetised with volatile anaesthesia or total intravenous anaesthesia. Patients had an iatrogenic surplus of approximately 4.1 l of fluid volume by the first postoperative day. N-terminal prohormone of brain natriuretic peptide increased on the first postoperative day (p < 0.001) and remained elevated after 30 days (p < 0.001) in both groups. Although postoperative echocardiographic alterations were most likely to be related to increased preload due to a substantial iatrogenic surplus of fluid, a component of peri-operative myocardial ischaemia cannot be excluded. Our hypothesis that volatile anaesthesia improved indices of cardiac function compared with total intravenous anaesthesia could not be verified. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

Deterioration of left ventricular chamber performance after bed rest : "cardiovascular deconditioning" or hypovolemia?

NASA Technical Reports Server (NTRS)

Perhonen, M. A.; Zuckerman, J. H.; Levine, B. D.; Blomqvist, C. G. (Principal Investigator)

2001-01-01

BACKGROUND: Orthostatic intolerance after bed rest is characterized by hypovolemia and an excessive reduction in stroke volume (SV) in the upright position. We studied whether the reduction in SV is due to a specific adaptation of the heart to head-down tilt bed rest (HDTBR) or acute hypovolemia alone. METHODS AND RESULTS: We constructed left ventricular (LV) pressure-volume curves from pulmonary capillary wedge pressure and LV end-diastolic volume and Starling curves from pulmonary capillary wedge pressure and SV during lower body negative pressure and saline loading in 7 men (25+/-2 years) before and after 2 weeks of -6 degrees HDTBR and after the acute administration of intravenous furosemide. Both HDTBR and hypovolemia led to a similar reduction in plasma volume. However, baseline LV end-diastolic volume decreased by 20+/-4% after HDTBR and by 7+/-2% after hypovolemia (interaction P<0.001). Moreover, SV was reduced more and the Starling curve was steeper during orthostatic stress after HDTBR than after hypovolemia. The pressure-volume curve showed a leftward shift and the equilibrium volume of the left ventricle was decreased after HDTBR; however, after hypovolemia alone, the curve was identical, with no change in equilibrium volume. Lower body negative pressure tolerance was reduced after both conditions; it decreased by 27+/-7% (P<0.05) after HDTBR and by 18+/-8% (P<0.05) after hypovolemia. CONCLUSIONS: Chronic HDTBR leads to ventricular remodeling, which is not seen with equivalent degrees of acute hypovolemia. This remodeling leads to a greater decrease in SV during orthostatic stress after bed rest than hypovolemia alone, potentially contributing to orthostatic intolerance.

Impairment of left ventricular function during coronary angioplastic occlusion evaluated with a nonimaging scintillation probe.

PubMed

Hartmann, A; Maul, F D; Zimny, M; Klepzig, H; Vallbracht, C; Kneissl, H G; Schräder, R; Hör, G; Kaltenbach, M

1991-09-01

Impairment of left ventricular function during controlled myocardial ischemia induced by coronary angioplasty has been reported from angiographic and echocardiographic studies. Ejection fraction, peak ejection, peak filling rates, and end-systolic and end-diastolic volumes were investigated before, during and after coronary occlusion on-line with a nonimaging scintillation probe. The study consisted of 18 patients (mean age 59 +/- 10 years) with coronary artery stenosis of greater than 70%. During balloon inflation of 60 seconds' duration, coronary occlusion pressure was 31.6 +/- 12 mm Hg. There was no significant change in heart rate. Delay between first and second dilatation was 109 +/- 63 seconds. Ejection fraction decreased from 53 +/- 16 to 40 +/- 12% (first dilatation, p less than 0.01) and to 39 +/- 14% (second dilatation, p less than 0.01) and recovered to 51 +/- 16% 5 minutes after the second dilatation. Peak ejection rate was significantly reduced during the first and second balloon inflations. Peak filling rate decreased from 2.5 +/- 0.8 to 2.0 +/- 0.7 end-diastolic volume.s-1 (first dilatation, p less than 0.01) and to 1.8 +/- 0.7 end-diastolic volume.s-1 (second dilatation, p less than 0.01) and remained reduced at 2.2 +/- 0.7 end-diastolic volume.s-1 (p = not significant) at 5 minutes after the second dilatation. End-systolic and end-diastolic volumes increased significantly during the first and second dilatations and returned to normal after dilatation. It is concluded that short, controlled myocardial ischemia during coronary angioplasty leads to a decrease in systolic and diastolic left ventricular function. Sequential dilatations do not further decrease function if a sufficient interval is kept.

Short-time-scale left ventricular systolic dynamics. Evidence for a common mechanism in both left ventricular chamber and heart muscle mechanics.

PubMed

Campbell, K B; Shroff, S G; Kirkpatrick, R D

1991-06-01

Based on the premise that short-time-scale, small-amplitude pressure/volume/outflow behavior of the left ventricular chamber was dominated by dynamic processes originating in cardiac myofilaments, a prototype model was built to predict pressure responses to volume perturbations. In the model, chamber pressure was taken to be the product of the number of generators in a pressure-bearing state and their average volumetric distortion, as in the muscle theory of A.F. Huxley, in which force was equal to the number of attached crossbridges and their average lineal distortion. Further, as in the muscle theory, pressure generators were assumed to cycle between two states, the pressure-bearing state and the non-pressure-bearing state. Experiments were performed in the isolated ferret heart, where variable volume decrements (0.01-0.12 ml) were removed at two commanded flow rates (flow clamps, -7 and -14 ml/sec). Pressure responses to volume removals were analyzed. Although the prototype model accounted for most features of the pressure responses, subtle but systematic discrepancies were observed. The presence or absence of flow and the magnitude of flow affected estimates of model parameters. However, estimates of parameters did not differ when the model was fitted to flow clamps with similar magnitudes of flows but different volume changes. Thus, prototype model inadequacies were attributed to misrepresentations of flow-related effects but not of volume-related effects. Based on these discrepancies, an improved model was built that added to the simple two-state cycling scheme, a pathway to a third state. This path was followed only in response to volume change. The improved model eliminated the deficiencies of the prototype model and was adequate in accounting for all observations. Since the template for the improved model was taken from the cycling crossbridge theory of muscle contraction, it was concluded that, in spite of the complexities of geometry, architecture, and regional heterogeneity of function and structure, crossbridge mechanisms dominated the short-time-scale dynamics of left ventricular chamber behavior.

Clinically significant change in stroke volume in pulmonary hypertension.

PubMed

van Wolferen, Serge A; van de Veerdonk, Marielle C; Mauritz, Gert-Jan; Jacobs, Wouter; Marcus, J Tim; Marques, Koen M J; Bronzwaer, Jean G F; Heymans, Martijn W; Boonstra, Anco; Postmus, Pieter E; Westerhof, Nico; Vonk Noordegraaf, Anton

2011-05-01

Stroke volume is probably the best hemodynamic parameter because it reflects therapeutic changes and contains prognostic information in pulmonary hypertension (PH). Stroke volume directly reflects right ventricular function in response to its load, without the correction of compensatory increased heart rate as is the case for cardiac output. For this reason, stroke volume, which can be measured noninvasively, is an important hemodynamic parameter to monitor during treatment. However, the extent of change in stroke volume that constitutes a clinically significant change is unknown. The aim of this study was to determine the minimal important difference (MID) in stroke volume in PH. One hundred eleven patients were evaluated at baseline and after 1 year of follow-up with a 6-min walk test (6MWT) and cardiac MRI. Using the anchor-based method with 6MWT as the anchor, and the distribution-based method, the MID of stroke volume change could be determined. After 1 year of treatment, there was, on average, a significant increase in stroke volume and 6MWT. The change in stroke volume was related to the change in 6MWT. Using the anchor-based method, an MID of 10 mL in stroke volume was calculated. The distribution-based method resulted in an MID of 8 to 12 mL. Both methods showed that a 10-mL change in stroke volume during follow-up should be considered as clinically relevant. This value can be used to interpret changes in stroke volume during clinical follow-up in PH.

Renal sympathetic denervation alleviates myocardial fibrosis following isoproterenol-induced heart failure.

PubMed

Wang, Neng; Zheng, Xiaoxin; Qian, Jin; Yao, Wei; Bai, Lu; Hou, Guo; Qiu, Xuan; Li, Xiaoyan; Jiang, Xuejun

2017-10-01

The aim of the present study was to determine if renal sympathetic denervation (RSD) may alleviate isoproterenol-induced left ventricle remodeling, and to identify the underlying mechanism. A total of 70 rats were randomly divided into control (n=15), sham operation (n=15), heart failure (HF) with sham operation (HF + sham; n=20) and HF with treatment (HF + RSD; n=20) groups. The HF model was established by subcutaneous injection of isoproterenol; six weeks later, 1eft ventricular internal diameter at end‑systole (LVIDs), left ventricular systolic posterior wall thickness (LVPWs), 1eft ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were measured. Plasma norepinephrine (NE), angiotensin II (Ang II) and aldosterone (ALD) levels were measured by ELISA. Myocardial collagen volume fraction (CVF) was determined by Masson's staining. Reverse transcription‑quantitative polymerase chain reaction was used to determine the mRNA expression levels of ventricular transforming growth factor‑β (TGF‑β), connective tissue growth factor (CTGF) and microRNAs (miRs), including miR‑29b, miR‑30c and miR‑133a. The results demonstrated that LVIDs and LVPWs in the HF + RSD group were significantly decreased compared with the HF + sham group. By contrast, LVFS and LVEF in the HF + RSD group were significantly increased compared with the HF + sham group. RSD significantly reduced the levels of plasma NE, Ang II and ALD. CVF in the HF + RSD group was reduced by 38.1% compared with the HF + sham group. Expression levels of TGF‑β and CTGF were decreased, whereas those of miR‑29b, miR‑30c and miR‑133a were increased, in the HF + RSD group compared with the HF + sham group. These results indicated that RSD alleviates isoproterenol‑induced left ventricle remodeling potentially via downregulation of TGF‑β/CTGF and upregulation of miR‑29b, miR‑30c and miR‑133a. RSD may therefore be an effective non‑drug therapy for the treatment of heart failure.

Renal sympathetic denervation alleviates myocardial fibrosis following isoproterenol-induced heart failure

PubMed Central

Wang, Neng; Zheng, Xiaoxin; Qian, Jin; Yao, Wei; Bai, Lu; Hou, Guo; Qiu, Xuan; Li, Xiaoyan; Jiang, Xuejun

2017-01-01

The aim of the present study was to determine if renal sympathetic denervation (RSD) may alleviate isoproterenol-induced left ventricle remodeling, and to identify the underlying mechanism. A total of 70 rats were randomly divided into control (n=15), sham operation (n=15), heart failure (HF) with sham operation (HF + sham; n=20) and HF with treatment (HF + RSD; n=20) groups. The HF model was established by subcutaneous injection of isoproterenol; six weeks later, 1eft ventricular internal diameter at end-systole (LVIDs), left ventricular systolic posterior wall thickness (LVPWs), 1eft ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were measured. Plasma norepinephrine (NE), angiotensin II (Ang II) and aldosterone (ALD) levels were measured by ELISA. Myocardial collagen volume fraction (CVF) was determined by Masson's staining. Reverse transcription-quantitative polymerase chain reaction was used to determine the mRNA expression levels of ventricular transforming growth factor-β (TGF-β), connective tissue growth factor (CTGF) and microRNAs (miRs), including miR-29b, miR-30c and miR-133a. The results demonstrated that LVIDs and LVPWs in the HF + RSD group were significantly decreased compared with the HF + sham group. By contrast, LVFS and LVEF in the HF + RSD group were significantly increased compared with the HF + sham group. RSD significantly reduced the levels of plasma NE, Ang II and ALD. CVF in the HF + RSD group was reduced by 38.1% compared with the HF + sham group. Expression levels of TGF-β and CTGF were decreased, whereas those of miR-29b, miR-30c and miR-133a were increased, in the HF + RSD group compared with the HF + sham group. These results indicated that RSD alleviates isoproterenol-induced left ventricle remodeling potentially via downregulation of TGF-β/CTGF and upregulation of miR-29b, miR-30c and miR-133a. RSD may therefore be an effective non-drug therapy for the treatment of heart failure. PMID:28849013

Relationship between shortening load, contractility, and myocardial energetics in intact dog.

PubMed

Dell'Italia, L J; Evanochko, W T; Blackwell, G G; Pearce, D J; Pohost, G M

1993-06-01

A canine model was developed to estimate left ventricular wall stress, volumes, contractility, and high-energy phosphate metabolites without the need for major surgery. A percutaneously inserted catheter-tip manometer was used to record high-fidelity left ventricular pressure while gradient echo cinemagnetic resonance (cine-MR) imaging alternated with in vivo 31P-nuclear magnetic resonance (NMR) spectroscopy during pharmacological maneuvers to increase cardiac work. Left ventricular circumferential wall stress, volumes, maximum rate of pressure development (dP/dtmax), and the ratio of phosphocreatine (PCr) to gamma-ATP (PCr/gamma-ATP) were recorded sequentially during control 1, dobutamine infusion, control 2, angiotensin infusion, and control 3 in five anesthetized, closed-chest dogs. PCr/gamma-ATP did not change significantly during controls 1-3, angiotensin, and dobutamine infusion. Left ventricular peak positive dP/dt (+dP/dtmax) increased significantly during dobutamine (3,338 +/- 831 mmHg/s, P < 0.001) but was unchanged during angiotensin (1,818 +/- 317 mmHg/s) and controls 1-3 (1,915 +/- 434 vs. 1,808 +/- 478 vs. 1,859 +/- 414 mmHg/s). However, dobutamine decreased the total systolic stress integral (area under the wall stress-time relationship) and end-diastolic and end-systolic volumes, whereas angiotensin increased these parameters compared with control conditions. The unchanged PCr/gamma-ATP is in accord with the results from other open-chest surface coil 31P-NMR experiments in the normal heart. Our assessment of left ventricular functional parameters provides new information that complements these more invasive studies in which heart rate-pressure product was measured during increases in cardiac work.(ABSTRACT TRUNCATED AT 250 WORDS)

Free-breathing whole-heart 3D cine magnetic resonance imaging with prospective respiratory motion compensation.

PubMed

Moghari, Mehdi H; Barthur, Ashita; Amaral, Maria E; Geva, Tal; Powell, Andrew J

2018-07-01

To develop and validate a new prospective respiratory motion compensation algorithm for free-breathing whole-heart 3D cine steady-state free precession (SSFP) imaging. In a 3D cine SSFP sequence, 4 excitations per cardiac cycle are re-purposed to prospectively track heart position. Specifically, their 1D image is reconstructed and routed into the scanner's standard diaphragmatic navigator processing system. If all 4 signals are in end-expiration, cine image data from the entire cardiac cycle is accepted for image reconstruction. Prospective validation was carried out in patients (N = 17) by comparing in each a conventional breath-hold 2D cine ventricular short-axis stack and a free-breathing whole-heart 3D cine data set. All 3D cine SSFP acquisitions were successful and the mean scan time was 5.9 ± 2.7 min. Left and right ventricular end-diastolic, end-systolic, and stroke volumes by 3D cine SSFP were all larger than those from 2D cine SSFP. This bias was < 6% except for right ventricular end-systolic volume that was 12%. The 3D cine images had a lower ventricular blood-to-myocardium contrast ratio, contrast-to-noise ratio, mass, and subjective quality score. The novel prospective respiratory motion compensation method for 3D cine SSFP imaging was robust and efficient and yielded slightly larger ventricular volumes and lower mass compared to breath-hold 2D cine imaging. Magn Reson Med 80:181-189, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Contemporary management of acute right ventricular failure: a statement from the Heart Failure Association and the Working Group on Pulmonary Circulation and Right Ventricular Function of the European Society of Cardiology.

PubMed

Harjola, Veli-Pekka; Mebazaa, Alexandre; Čelutkienė, Jelena; Bettex, Dominique; Bueno, Hector; Chioncel, Ovidiu; Crespo-Leiro, Maria G; Falk, Volkmar; Filippatos, Gerasimos; Gibbs, Simon; Leite-Moreira, Adelino; Lassus, Johan; Masip, Josep; Mueller, Christian; Mullens, Wilfried; Naeije, Robert; Nordegraaf, Anton Vonk; Parissis, John; Riley, Jillian P; Ristic, Arsen; Rosano, Giuseppe; Rudiger, Alain; Ruschitzka, Frank; Seferovic, Petar; Sztrymf, Benjamin; Vieillard-Baron, Antoine; Yilmaz, Mehmet Birhan; Konstantinides, Stavros

2016-03-01

Acute right ventricular (RV) failure is a complex clinical syndrome that results from many causes. Research efforts have disproportionately focused on the failing left ventricle, but recently the need has been recognized to achieve a more comprehensive understanding of RV anatomy, physiology, and pathophysiology, and of management approaches. Right ventricular mechanics and function are altered in the setting of either pressure overload or volume overload. Failure may also result from a primary reduction of myocardial contractility owing to ischaemia, cardiomyopathy, or arrhythmia. Dysfunction leads to impaired RV filling and increased right atrial pressures. As dysfunction progresses to overt RV failure, the RV chamber becomes more spherical and tricuspid regurgitation is aggravated, a cascade leading to increasing venous congestion. Ventricular interdependence results in impaired left ventricular filling, a decrease in left ventricular stroke volume, and ultimately low cardiac output and cardiogenic shock. Identification and treatment of the underlying cause of RV failure, such as acute pulmonary embolism, acute respiratory distress syndrome, acute decompensation of chronic pulmonary hypertension, RV infarction, or arrhythmia, is the primary management strategy. Judicious fluid management, use of inotropes and vasopressors, assist devices, and a strategy focusing on RV protection for mechanical ventilation if required all play a role in the clinical care of these patients. Future research should aim to address the remaining areas of uncertainty which result from the complexity of RV haemodynamics and lack of conclusive evidence regarding RV-specific treatment approaches. © 2016 The Authors European Journal of Heart Failure © 2016 European Society of Cardiology.

Refined 4-group classification of left ventricular hypertrophy based on ventricular concentricity and volume dilatation outlines distinct noninvasive hemodynamic profiles in a large contemporary echocardiographic population.

PubMed

Barbieri, Andrea; Rossi, Andrea; Gaibazzi, Nicola; Erlicher, Andrea; Mureddu, Gian Francesco; Frattini, Silvia; Faden, Giacomo; Manicardi, Marcella; Beraldi, Monica; Agostini, Francesco; Lazzarini, Valentina; Moreo, Antonella; Temporelli, Pier Luigi; Faggiano, Pompilio

2018-05-23

Left ventricular hypertrophy (LVH) may reflect a wide variety of physiologic and pathologic conditions. Thus, it can be misleading to consider all LVH to be homogenous or similar. Refined 4-group classification of LVH based on ventricular concentricity and dilatation may be identified. To determine whether the 4-group classification of LVH identified distinct phenotypes, we compared their association with various noninvasive markers of cardiac stress. Cohort of unselected adult outpatients referred to a seven tertiary care echocardiographic laboratory for any indication in a 2-week period. We evaluated the LV geometric patterns using validated echocardiographic indexation methods and partition values. Standard echocardiography was performed in 1137 consecutive subjects, and LVH was found in 42%. The newly proposed 4-group classification of LVH was applicable in 88% of patients. The most common pattern resulted in concentric LVH (19%). The worst functional and hemodynamic profile was associated with eccentric LVH and those with mixed LVH had a higher prevalence of reduced EF than those with concentric LVH (P < .001 for all). The new 4-group classification of LVH system showed distinct differences in cardiac function and noninvasive hemodynamics allowing clinicians to distinguish different LV hemodynamic stress adaptations in patients with LVH. © 2018 Wiley Periodicals, Inc.

Large CSF Volume Not Attributable to Ventricular Volume in Schizotypal Personality Disorder

PubMed Central

Dickey, Chandlee C.; Shenton, Martha E.; Hirayasu, Yoshio; Fischer, Iris; Voglmaier, Martina M.; Niznikiewicz, Margaret A.; Seidman, Larry J.; Fraone, Stephanie; McCarley, Robert W.

2010-01-01

Objective The purpose of this study was to determine whether schizotypal personality disorder, which has the same genetic diathesis as schizophrenia, manifests abnormalities in whole-brain and CSF volumes. Method Sixteen right-handed and neuroleptic-naive men with schizotypal personality disorder were recruited from the community and were age-matched to 14 healthy comparison subjects. Magnetic resonance images were obtained from the subjects and automatically parcellated into CSF, gray matter, and white matter. Subsequent manual editing separated cortical from noncortical gray matter. Lateral ventricles and temporal horns were also delineated. Results The men with schizotypal personality disorder had larger CSF volumes than the comparison subjects; the difference was not attributable to larger lateral ventricles. The cortical gray matter was somewhat smaller in the men with schizotypal personality disorder, but the difference was not statistically significant. Conclusions Consistent with many studies of schizophrenia, this examination of schizotypal personality disorder indicated abnormalities in brain CSF volumes. PMID:10618012

Effect of sex on wasted left ventricular effort following maximal exercise.

PubMed

Lane, A D; Ranadive, S M; Yan, H; Kappus, R M; Cook, M D; Sun, P; Woods, J A; Wilund, K; Fernhall, B

2013-09-01

Wasted left ventricular effort (∆Ew) refers to work required of the left ventricle to eject blood that does not result in increased stroke volume and is related to left ventricular hypertrophy. Literature shows that men and women have differing ventricular and vascular responses to and following exercise. Our purpose was to determine how ∆Ew changes post-exercise in men and women and examine potential mechanisms. We hypothesized a reduction in ∆Ew that would be greater in men and that central pulse wave velocity and wave intensity (WIA) would be related to ∆Ew. Blood pressures, central pulse wave velocity (cPWV), and WIA were obtained at rest, 15 and 30 min after maximal exercise. Both sexes reduced ∆Ew post-maximal exercise (p>0.05 for interaction), but women had higher ∆Ew at each time point (p<0.05). The first peak of WIA increased 15 min post-exercise only in women (p<0.05). cPWV was attenuated (p<0.05) in women at 15 min and men at 30 min (p<0.05) post-exercise with a significant time by sex interaction (p<0.05). WIA (1st peak) was correlated (p<0.05) to ∆Ew in both sexes before and 15 min post-exercise, but cPWV was only associated with ∆Ew in men at 30 min post-exercise. We conclude that both sexes decrease ∆Ew after maximal exercise, but vascular and ventricular changes associated with the attenuation of ∆Ew are not uniform between sexes. © Georg Thieme Verlag KG Stuttgart · New York.

Effect of free fatty acids on myocardial function and metabolism in the ischemic dog heart

PubMed Central

Kjekshus, John K.; Mjøs, Ole D.

1972-01-01

Since elevation of plasma concentrations of free fatty acids (FFA) increases myocardial oxygen consumption without influencing mechanical performance in normal hearts, it was the purpose of this study to determine whether FFA would modify mechanical performance at limited oxygen supply. Left coronary blood flow was reduced by gradual clamping of a shunt from the left carotid artery until moderate ventricular dilatation supervened. Left ventricular systolic pressure (LVSP), its maximal rate of rise (dP/dt) and stroke volume (SV) were unchanged or slightly reduced. The ischemia resulted in a decrease in myocardial oxygen consumption (MVO2) from 9.7±1.1 ml/min to 7.9±0.8 ml/min, and myocardial lactate uptake was reduced or reversed to excretion. Increasing the plasma concentrations of FFA from 359±47 μEq/1 to 3688±520 μEq/1 by intravenous infusion of a triglyceride emulsion and heparin resulted in further ventricular dilatation, accompanied by increased excretion of lactate. The ventricular decompensation and enhancement of anaerobic myocardial metabolism associated with increased uptake of FFA was not related to changes in coronary flow, MVO2, or LVSP. dP/dt and SV were virtually unchanged. Intravenous infusion of glucose/insulin, which lowered plasma concentrations of FFA, reversed ventricular dilatation and lactate excretion. The data support the hypothesis that high concentrations of FFA play a significant role in increasing myocardial oxygen requirement and thereby promote depression of contractility of the hypoxic heart in experimental animals. Images PMID:5032525

Dofetilide promotes repolarization abnormalities in perfused Guinea-pig heart.

PubMed

Osadchii, Oleg E

2012-12-01

Dofetilide is class III antiarrhythmic agent which prolongs cardiac action potential duration because of selective inhibition of I (Kr), the rapid component of the delayed rectifier K(+) current. Although clinical studies reported on proarrhythmic risk associated with dofetilide treatment, the contributing electrophysiological mechanisms remain poorly understood. This study was designed to determine if dofetilide-induced proarrhythmia may be attributed to abnormalities in ventricular repolarization and refractoriness. The monophasic action potential duration and effective refractory periods (ERP) were assessed at distinct epicardial and endocardial sites along with volume-conducted ECG recordings in isolated, perfused guinea-pig heart preparations. Dofetilide was found to produce the reverse rate-dependent prolongation of ventricular repolarization, increased the steepness of action potential duration rate adaptation, and amplified transepicardial variability in electrical restitution kinetics. Dofetilide also prolonged the T peak-to-end interval on ECG, and elicited a greater prolongation of endocardial than epicardial ERP, thereby increasing transmural dispersion of refractoriness. At epicardium, dofetilide prolonged action potential duration to a greater extent than ERP, thus extending the critical interval for ventricular re-excitation. This change was associated with triangulation of epicardial action potential because of greater dofetilide-induced prolonging effect at 90 % than 30 % repolarization. Premature ectopic beats and spontaneous short-lasting episodes of monomorphic ventricular tachycardia were observed in 44 % of dofetilide-treated heart preparations. Proarrhythmic potential of dofetilide in guinea-pig heart is attributed to steepened electrical restitution, increased transepicardial variability in electrical restitution kinetics, amplified transmural dispersion of refractoriness, increased critical interval for ventricular re-excitation, and triangulation of epicardial action potential.

Evaluation of right heart function in a rat model using modified echocardiographic views.

PubMed

Bernardo, Ivan; Wong, James; Wlodek, Mary E; Vlahos, Ross; Soeding, Paul

2017-01-01

Echocardiography plays a major role in assessing cardiac function in animal models. We investigated use of a modified parasternal mid right-ventricular (MRV) and right ventricle (RV) outflow (RVOT) view, in assessing RV size and function, and the suitability of advanced 2D-strain analysis. 15 WKY rats were examined using transthoracic echocardiography. The left heart was assessed using standard short and long axis views. For the right ventricle a MRV and RVOT view were used to measure RV chamber and free wall area. 2D-strain analysis was applied to both ventricles using off-line analysis. RV chamber volume was determined by injection of 2% agarose gel, and RV free wall dissected and weighed. Echocardiography measurement was correlated with necropsy findings. The RV mid-ventricular dimension (R1) was 0.42±0.07cm and the right ventricular outflow tract dimension (R2) was 0.34±0.06cm, chamber end-diastolic area measurements were 0.38±0.09cm2 and 0.29±0.08cm2 for MRV and RVOT views respectively. RVOT and MRV chamber area correlated with gel mass. Doppler RV stroke volume was 0.32±0.08ml, cardiac output (CO) 110±27 ml.min-1 and RV free wall contractility assessed using 2D-strain analysis was demonstrated. We have shown that modified MRV and RVOT views can provide detailed assessment of the RV in rodents, with 2D-strain analysis of the RV free wall potentially feasible.

Interleukin-6 Mediates Myocardial Fibrosis, Concentric Hypertrophy and Diastolic Dysfunction in Rats

PubMed Central

Meléndez, Giselle C.; McLarty, Jennifer L.; Levick, Scott P.; Du, Yan; Janicki, Joseph S.; Brower, Gregory L.

2010-01-01

While there is a correlation between hypertension and levels of IL-6, the exact role of this cytokine in myocardial remodeling is unknown. This is complicated by the variable tissue and circulating levels of IL-6 reported in numerous experimental models of hypertension. Accordingly, we explored the hypothesis that elevated levels of IL-6 mediate adverse myocardial remodeling. To this end, adult male Sprague Dawley rats were infused with IL-6 (2.5 μg·kg-1·hr-1, IP) for 7 days via osmotic minipump and compared to vehicle infused aged-matched controls. Left ventricular function was evaluated using a blood-perfused isolated heart preparation. In addition, myocardial interstitial collagen volume fraction and isolated cardiomyocyte size were also assessed. Isolated adult cardiac fibroblast experiments were performed to determine the importance of the soluble IL-6 receptor in mediating cardiac fibrosis. IL-6 infusions in vivo resulted in concentric left ventricular hypertrophy, increased ventricular stiffness, a marked increase in collagen volume fraction (6.2 vs. 1.7%; p < 0.001), and proportional increases in cardiomyocyte width and length; all independent of blood pressure. The soluble IL-6 receptor in combination with IL-6 was found to be essential in increasing collagen content regulated by isolated cardiac fibroblasts, and also played a role in mediating a phenotypic conversion to myofibroblasts. These novel observations demonstrate that IL-6 induces a myocardial phenotype almost identical to that of the hypertensive heart, identifying IL-6 as potentially important in this remodeling process. PMID:20606113

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

Transthoracic 3D echocardiographic left heart chamber quantification in patients with bicuspid aortic valve disease.

PubMed

van den Hoven, Allard T; Mc-Ghie, Jackie S; Chelu, Raluca G; Duijnhouwer, Anthonie L; Baggen, Vivan J M; Coenen, Adriaan; Vletter, Wim B; Dijkshoorn, Marcel L; van den Bosch, Annemien E; Roos-Hesselink, Jolien W

2017-12-01

Integration of volumetric heart chamber quantification by 3D echocardiography into clinical practice has been hampered by several factors which a new fully automated algorithm (Left Heart Model, (LHM)) may help overcome. This study therefore aims to evaluate the feasibility and accuracy of the LHM software in quantifying left atrial and left ventricular volumes and left ventricular ejection fraction in a cohort of patients with a bicuspid aortic valve. Patients with a bicuspid aortic valve were prospectively included. All patients underwent 2D and 3D transthoracic echocardiography and computed tomography. Left atrial and ventricular volumes were obtained using the automated program, which did not require manual contour detection. For comparison manual and semi-automated measurements were performed using conventional 2D and 3D datasets. 53 patients were included, in four of those patients no 3D dataset could be acquired. Additionally, 12 patients were excluded based on poor imaging quality. Left ventricular end-diastolic and end-systolic volumes and ejection fraction calculated by the LHM correlated well with manual 2D and 3D measurements (Pearson's r between 0.43 and 0.97, p < 0.05). Left atrial volume (LAV) also correlated significantly although LHM did estimate larger LAV compared to both 2DE and 3DE (Pearson's r between 0.61 and 0.81, p < 0.01). The fully automated software works well in a real-world setting and helps to overcome some of the major hurdles in integrating 3D analysis into daily practice, as it is user-independent and highly reproducible in a group of patients with a clearly defined and well-studied valvular abnormality.

Limited Ventricular Preload is the Main Reason for Reduced Stress Reserve After Atrial Baffle Repair.

PubMed

Eicken, Andreas; Michel, Julia; Hager, Alfred; Tanase, Daniel; Kaemmerer, Harald; Cleuziou, Julie; Hess, John; Ewert, Peter

2017-02-01

The atrial baffle repair (ABR) significantly improved the fate of patients with transposition of the great arteries (TGA). However, these patients show impaired exercise tolerance and some present severe decline of systemic ventricular function. Intrinsic myocardial weakness, low heart rate response to exercise and diastolic filling impairment are discussed to be causative. Forty-nine long-term survivors with TGA (median age 23.7 year) after ABR were catheterized with measured oxygen consumption in four conditions (baseline, volume, atrial pacing, dobutamine) and the results were compared to 10 normal controls. Median cardiac output was significantly lower in the ABR group (2.2 vs. 2.6 l/min/m 2 ; p = 0.015), and systemic resistance was significantly elevated (28.9 vs. 22.2 U m 2 ; p = 0.04) in comparison with normals. While stroke volume rose by 27% in the control group, it dropped by 7% in patients after ABR at atrial pacing (80/min). Stroke volume increase after dobutamine was significantly lower after ABR in comparison with normal controls (34 vs. 106%; p = 0.001). Higher NYHA class (p = 0.043), degree of tricuspid regurgitation (p = 0.009) and ventricular function (p = 0.028) were associated with lower stroke volume increase. Limited exercise capability of patients after ABR for TGA is primarily due to limited diastolic filling of the ventricles due to stiff non-compliant atrial pathways. Elevated systemic resistance may lead to severe myocardial hypertrophy with possible ischemia and contribute to the multifactorial decline of ventricular function in some patients.

Vasopressin V2 receptor antagonist tolvaptan is effective in heart failure patients with reduced left ventricular systolic function and low blood pressure.

PubMed

Suzuki, Satoshi; Yoshihisa, Akiomi; Yamaki, Takayoshi; Sugimoto, Koichi; Kunii, Hiroyuki; Nakazato, Kazuhiko; Abe, Yukihiko; Saito, Tomiyoshi; Ohwada, Takayuki; Suzuki, Hitoshi; Saitoh, Shu-ichi; Kubota, Isao; Takeishi, Yasuchika

2015-01-01

Diuresis is a major therapy for the reduction of congestive symptoms in acute decompensated heart failure (ADHF) patients. Carperitide has natriuretic and vasodilatory effects, and tolvaptan produces water excretion without electrolyte excretion. We previously reported the usefulness of tolvaptan compared to carperitide in ADHF patients with fluid volume retention. The purpose of this study was to examine whether the efficacy of tolvaptan was altered in ADHF patients with reduced left ventricular systolic function and in those with hypotension. A total of 109 hospitalized ADHF patients were randomly assigned to either a tolvaptan or a carperitide treatment group. Baseline clinical characteristics were not different between the two groups. We divided these patients based on the left ventricular ejection fraction (EF) by echocardiography, and blood pressure (BP) at the time of admission. Daily urine volume between the tolvaptan and carperitide groups in patients with preserved EF (≥ 50%) was not different, however, in those with reduced EF (< 50%), the urine volume was significantly higher in the tolvaptan group than in the carperitide group (day 2, 3, 4, P < 0.05 for all). Daily urine volume did not differ between these two groups in the high blood pressure group (BP ≥ 140 mmHg), but was significantly higher in the tolvaptan group than in the carperitide group (day 1, P = 0.021; day 3, P = 0.017) in the low blood pressure group (BP < 140 mmHg). The present study reveals that tolvaptan is more effective than carperitide, especially in ADHF patients with reduced left ventricular systolic function and without hypertension.

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

Mechanisms of lower body negative pressure-induced syncope

NASA Astrophysics Data System (ADS)

Davrath, Linda Ruble

Although extensively investigated, the mechanisms of post-spaceflight orthostatic intolerance have not been elucidated. The working hypothesis was that a markedly reduced left ventricular end-systolic volume (LVESV) would be achieved during progressive, presyncopal-limited LBNP and would cause bradycardia and a fall in blood pressure, thus triggering syncope. Eight healthy men, age 25.1 ± 1.3 years, volunteered for the study. Subjects were exposed to graded levels of LBNP on two separate occasions. Changes in left ventricular end-diastolic volume and LVESV were measured, using two-dimensional echocardiography, at each stage of LBNP from rest to presyncope. Plasma venous blood samples were withdrawn at the end of each stage of the LBNP protocol for the measurement of plasma venous catecholamines and plasma renin activity (PRA). Catecholamines were analyzed by HPLC with electro-chemical detection, and PRA was determined by radioimmunoassay. All subjects reached presyncope during the LBNP. LVESV decreased by 28% at presyncope with no evidence of ventricular cavity obliteration. Norepinephrine (NE) increased by 44% from rest to presyncope, but no epinephrine surge was detected (35% increase from rest to presyncope). These data indicate that it is possible to initiate syncope with only a 28% decrease in LVESV, and that sympatho-inhibition and bradycardia are not required elements for syncope to occur. To investigate the effect of moderate sodium restriction on cardiovascular hemodynamics and orthostatic tolerance, presyncopal LBNP testing was performed. Urinary sodium excretion was significantly higher on the normal-sodium diet when compared with the sodium-restricted diet, but urinary potassium was not different. Cumulative stress index (655 ± 460 on normal-sodium diet vs. 639 ± 388 on sodium-restricted diet) scores were not different. Cardiac volumes, blood pressure and total peripheral resistance were not different at any stage of the LBNP between the diets, nor were plasma catecholamine levels. Heart rate was significantly higher at presyncope on the sodium-restricted diet. Plasma renin activity was significantly higher during sodium restriction at rest, and during all stages of LBNP. Moderate dietary sodium restriction was not accompanied by apparent plasma volume reduction (hematocrit, body weight change), and did not appear to be detrimental to orthostatic function.

Satisfactory rate of postprocessing visualization of standard fetal cardiac views from 4-dimensional cardiac volumes acquired during routine ultrasound practice by experienced sonographers in peripheral centers.

PubMed

Rizzo, Giuseppe; Capponi, Alessandra; Pietrolucci, Maria Elena; Capece, Giuseppe; Cimmino, Ernesto; Colosi, Enrico; Ferrentino, Salvatore; Sica, Carmine; Di Meglio, Aniello; Arduini, Domenico

2011-01-01

The aim of this study was to evaluate the feasibility of visualizing standard cardiac views from 4-dimensional (4D) cardiac volumes obtained at ultrasound facilities with no specific experience in fetal echocardiography. Five sonographers prospectively recorded 4D cardiac volumes starting from the 4-chamber view on 500 consecutive pregnancies at 19 to 24 weeks' gestation undergoing routine ultrasound examinations (100 pregnancies for each sonographer). Volumes were sent to the referral center, and 2 independent reviewers with experience in 4D fetal echocardiography assessed their quality in the display of the abdominal view, 4-chamber view, left and right ventricular outflow tracts, and 3-vessel and trachea view. Cardiac volumes were acquired in 474 of 500 pregnancies (94.8%). The 2 reviewers respectively acknowledged the presence of satisfactory images in 92.4% and 93.6% of abdominal views, 91.5% and 93.0% of 4-chamber views, in 85.0% and 86.2% of left ventricular outflow tracts, 83.9% and 84.5% of right ventricular outflow tracts, and 85.2% and 84.5% of 3-vessel and trachea views. The presence of a maternal body mass index of greater than 30 altered the probability of achieving satisfactory cardiac views, whereas previous maternal lower abdominal surgery did not affect the quality of reconstructed cardiac views. In conclusion, cardiac volumes acquired by 4D sonography in peripheral centers showed high enough quality to allow satisfactory diagnostic cardiac views.

Nebivolol prevents remodeling in a rat myocardial infarction model: an echocardiographic study.

PubMed

Mercanoğlu, Güldem Olguner; Pamukçu, Burak; Safran, Nurhas; Mercanoğlu, Fehmi; Fici, Francesco; Güngör, Mehmet

2010-02-01

Ventricular remodeling (VR) which develops after myocardial infarction (MI) plays an important role in progressive left ventricular dysfunction. We aimed to investigate the role of nebivolol treatment on VR after a MI in a rat ischemia-reperfusion model. Rats were divided into 3 groups of 12 each: sham operated (sham-control), MI-induced (MI-control) and nebivolol treated (MI-nebivolol). Left ventricular (LV) diameters, volumes, and diastolic filling parameters were evaluated by echocardiography. On the 28th day, after recording the systemic and LV pressures and determining the plasma nitric oxide (NO) and peroxynitrite (ONOO-) levels , animals were sacrificed and heart, body and LV weights (HW, BW, LVW) were measured and infarct sizes were determined. Results were evaluated statistically by ANOVA for repeated measurements 3x3 factorial design with post-hoc Bonferroni test. After MI, while VR (an increase in LV diameters and volumes associated with a decrease in EF, FS and posterior wall thickness change (LWPc) was significant in MI-control rats (p<0.05 for; all comparisons) these changes were significantly less in MI-nebivolol group (p=0.08 and p=0.06 for EF and FS respectively). LV end diastolic pressure (LVEDP) was lower (p<0.005) and Delta+/- dp/dt's (p<0.05) were higher in MI-nebivolol group compared to MI-control animals. Although infarct sizes were similar in MI-induced groups (p=0.79); LVW/HW and HW/BW's were significantly greater in the MI-control group compared to sham-control (p<0.01 for all comparisons), these changes were not statistically significant in MI-nebivolol group. The increase in plasma NO and ONOO- levels were also prevented with nebivolol. Nebivolol therapy reduced the effects of VR in rats after MI. These beneficial effects were not related to its heart rate and blood pressure reducing effects. Nitric oxide regulatory action of this compound may contribute these beneficial effects on VR developed after MI.

Implantation of the Medtronic Harmony Transcatheter Pulmonary Valve Improves Right Ventricular Size and Function in an Ovine Model of Postoperative Chronic Pulmonary Insufficiency.

PubMed

Schoonbeek, Rosanne C; Takebayashi, Satoshi; Aoki, Chikashi; Shimaoka, Toru; Harris, Matthew A; Fu, Gregory L; Kim, Timothy S; Dori, Yoav; McGarvey, Jeremy; Litt, Harold; Bouma, Wobbe; Zsido, Gerald; Glatz, Andrew C; Rome, Jonathan J; Gorman, Robert C; Gorman, Joseph H; Gillespie, Matthew J

2016-10-01

Pulmonary insufficiency is the nexus of late morbidity and mortality after transannular patch repair of tetralogy of Fallot. This study aimed to establish the feasibility of implantation of the novel Medtronic Harmony transcatheter pulmonary valve (hTPV) and to assess its effect on pulmonary insufficiency and ventricular function in an ovine model of chronic postoperative pulmonary insufficiency. Thirteen sheep underwent baseline cardiac magnetic resonance imaging, surgical pulmonary valvectomy, and transannular patch repair. One month after transannular patch repair, the hTPV was implanted, followed by serial magnetic resonance imaging and computed tomography imaging at 1, 5, and 8 month(s). hTPV implantation was successful in 11 animals (85%). There were 2 procedural deaths related to ventricular fibrillation. Seven animals survived the entire follow-up protocol, 5 with functioning hTPV devices. Two animals had occlusion of hTPV with aneurysm of main pulmonary artery. A strong decline in pulmonary regurgitant fraction was observed after hTPV implantation (40.5% versus 8.3%; P=0.011). Right ventricular end diastolic volume increased by 49.4% after transannular patch repair (62.3-93.1 mL/m 2 ; P=0.028) but was reversed to baseline values after hTPV implantation (to 65.1 mL/m 2 at 8 months, P=0.045). Both right ventricular ejection fraction and left ventricular ejection fraction were preserved after hTPV implantation. hTPV implantation is feasible, significantly reduces pulmonary regurgitant fraction, facilitates right ventricular volume improvements, and preserves biventricular function in an ovine model of chronic pulmonary insufficiency. This percutaneous strategy could potentially offer an alternative for standard surgical pulmonary valve replacement in dilated right ventricular outflow tracts, permitting lower risk, nonsurgical pulmonary valve replacement in previously prohibitive anatomies. © 2016 American Heart Association, Inc.

Endurance sport and "cardiac injury": a prospective study of recreational ironman athletes.

PubMed

Leischik, Roman; Spelsberg, Norman

2014-09-03

Participation in triathlon competitions has increased in recent years. Many studies have described left or right ventricular injury in endurance athletes. The goal of this study was to examine the right and left ventricular cardiac structures and function and dynamic cardio-pulmonary performance in a large cohort of middle- and long-distance triathletes. 87 triathletes (54 male and 33 female) were examined using spiroergometry and echocardiography. The inclusion criterion was participation in at least one middle- or long distance triathlon. Male triathletes showed a maximum oxygen absorption of 58.1 ± 8.6 mL/min/kg (female triathletes 52.8 ± 5.7 mL/min/kg), maximum ergometer performance of 347.8 ± 49.9 W (female triathletes 264.5 ± 26.1 W). Left ventricular ejection fraction (EF) was normal (male triathletes EF: 61.9% ± 3%, female triathletes EF: 63.0% ± 2.7%) and systolic right ventricular area change fraction (RV AFC%) showed normal values (males RV AFC%: 33.5% ± 2.2%, females 32.2% ± 2.8%). Doppler indices of diastolic function were normal in both groups. With respect to the echocardiographic readings the left ventricular mass for males and females were 217.7 ± 41.6 g and 145.9 ± 31.3 g, respectively. The relative wall thickness for males was 0.50 ± 0.07, whereas it was 0.47 ± 0.09 for females. The probability of left ventricular mass >220 g increased with higher blood pressure during exercise (OR: 1.027, CI 1.002-1.052, p = 0.034) or with higher training volume (OR: 1.23, CI 1.04-1.47, p = 0.019). Right or left ventricular dysfunction could not be found, although the maximal participation in triathlon competitions was 29 years. A left ventricular mass >220 g is more likely to occur with higher arterial pressure during exercise and with a higher training volume.

Endurance Sport and “Cardiac Injury”: A Prospective Study of Recreational Ironman Athletes

PubMed Central

Leischik, Roman; Spelsberg, Norman

2014-01-01

Background: Participation in triathlon competitions has increased in recent years. Many studies have described left or right ventricular injury in endurance athletes. The goal of this study was to examine the right and left ventricular cardiac structures and function and dynamic cardio-pulmonary performance in a large cohort of middle- and long-distance triathletes. Methods: 87 triathletes (54 male and 33 female) were examined using spiroergometry and echocardiography. The inclusion criterion was participation in at least one middle- or long distance triathlon. Results: Male triathletes showed a maximum oxygen absorption of 58.1 ± 8.6 mL/min/kg (female triathletes 52.8 ± 5.7 mL/min/kg), maximum ergometer performance of 347.8 ± 49.9 W (female triathletes 264.5 ± 26.1 W). Left ventricular ejection fraction (EF) was normal (male triathletes EF: 61.9% ± 3%, female triathletes EF: 63.0% ± 2.7%) and systolic right ventricular area change fraction (RV AFC%) showed normal values (males RV AFC%: 33.5% ± 2.2%, females 32.2% ± 2.8%). Doppler indices of diastolic function were normal in both groups. With respect to the echocardiographic readings the left ventricular mass for males and females were 217.7 ± 41.6 g and 145.9 ± 31.3 g, respectively. The relative wall thickness for males was 0.50 ± 0.07, whereas it was 0.47 ± 0.09 for females. The probability of left ventricular mass >220 g increased with higher blood pressure during exercise (OR: 1.027, CI 1.002–1.052, p = 0.034) or with higher training volume (OR: 1.23, CI 1.04–1.47, p = 0.019). Conclusions: Right or left ventricular dysfunction could not be found, although the maximal participation in triathlon competitions was 29 years. A left ventricular mass >220 g is more likely to occur with higher arterial pressure during exercise and with a higher training volume. PMID:25192145

Ethical considerations of transparency, informed consent, and nudging in a patient with paediatric aortic stenosis and symptomatic left ventricular endocardial fibroelastosis.

PubMed

Mavroudis, Constantine D; Cook, Thomas; Jacobs, Jeffrey P; Mavroudis, Constantine

2016-12-01

A 9-year-old boy who was born with bicuspid aortic stenosis underwent two unsuccessful aortic valvuloplasty interventions, and by 2 years of age he developed restrictive cardiomyopathy caused by left ventricular endocardial fibroelastosis and diastolic dysfunction. The attending cardiologist referred the patient to a high-volume, high-profile congenital cardiac surgical programme 1000 miles away that has a team with considerable experience with left ventricular endocardial fibroelastosis resection and a reputation of achieving good results. Owing to problems with insurance coverage, the parents sought other options for the care of their child in their home state. Dr George Miller is a well-respected local congenital and paediatric cardiac surgeon with considerable experience with the Ross operation as well as with right ventricular endocardial fibroelastosis resection. When talking with Dr Miller, he implied that there is little difference between right ventricular endocardial fibroelastosis and left ventricular endocardial fibroelastosis resection, and stated that he would perform the operation with low mortality based on his overall experience. Dr Miller stated that the local institution could provide an equivalent surgical procedure with comparable outcomes, without the patient and family having to travel out of state. A fundamental dilemma that often arises in clinical surgical practice concerns the conduct of assessing and performing new procedures, especially in rare cases, for which the collective global experience is scant. Although Dr Miller has performed right ventricular endocardial fibroelastosis resection, this procedure differs from left ventricular endocardial fibroelastosis resection, and he cannot be sure that he will indeed be able to perform the procedure better than the high-volume surgeon. This ethical situation is best understood in terms of the principles of respect for patient autonomy, beneficence, non-maleficence, and justice. The tension between the imperatives of beneficence and the obligation to respect the autonomy of the patient by acting only with the patient's best interest in mind is discussed.

Left ventricular volume estimation in cardiac three-dimensional ultrasound: a semiautomatic border detection approach.

PubMed

van Stralen, Marijn; Bosch, Johan G; Voormolen, Marco M; van Burken, Gerard; Krenning, Boudewijn J; van Geuns, Robert-Jan M; Lancée, Charles T; de Jong, Nico; Reiber, Johan H C

2005-10-01

We propose a semiautomatic endocardial border detection method for three-dimensional (3D) time series of cardiac ultrasound (US) data based on pattern matching and dynamic programming, operating on two-dimensional (2D) slices of the 3D plus time data, for the estimation of full cycle left ventricular volume, with minimal user interaction. The presented method is generally applicable to 3D US data and evaluated on data acquired with the Fast Rotating Ultrasound (FRU-) Transducer, developed by Erasmus Medical Center (Rotterdam, the Netherlands), a conventional phased-array transducer, rotating at very high speed around its image axis. The detection is based on endocardial edge pattern matching using dynamic programming, which is constrained by a 3D plus time shape model. It is applied to an automatically selected subset of 2D images of the original data set, for typically 10 equidistant rotation angles and 16 cardiac phases (160 images). Initialization requires the drawing of four contours per patient manually. We evaluated this method on 14 patients against MRI end-diastole and end-systole volumes. Initialization requires the drawing of four contours per patient manually. We evaluated this method on 14 patients against MRI end-diastolic (ED) and end-systolic (ES) volumes. The semiautomatic border detection approach shows good correlations with MRI ED/ES volumes (r = 0.938) and low interobserver variability (y = 1.005x - 16.7, r = 0.943) over full-cycle volume estimations. It shows a high consistency in tracking the user-defined initial borders over space and time. We show that the ease of the acquisition using the FRU-transducer and the semiautomatic endocardial border detection method together can provide a way to quickly estimate the left ventricular volume over the full cardiac cycle using little user interaction.

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.

The value of right ventricular longitudinal strain in the evaluation of adult patients with repaired tetralogy of Fallot: a new tool for a contemporary challenge.

PubMed

Almeida-Morais, Luís; Pereira-da-Silva, Tiago; Branco, Luísa; Timóteo, Ana T; Agapito, Ana; de Sousa, Lídia; Oliveira, José A; Thomas, Boban; Jalles-Tavares, Nuno; Soares, Rui; Galrinho, Ana; Cruz-Ferreira, Rui

2017-04-01

The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients. Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method. In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was -16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=-0.40) and right ventricular ejection fraction (r=-0.45) (all p<0.05), which in turn showed linear correlation with right ventricular fractional area change (r=0.50), pulmonary regurgitation colour length (r=0.35), right ventricular end-systolic volume (r=-0.60), and left ventricular ejection fraction (r=0.36) (all p<0.05). Longitudinal strain (β=-0.72, 95% confidence interval -1.41, -0.15) and left ventricular ejection fraction (β=0.39, 95% confidence interval 0.11, 0.67) were independently associated with right ventricular ejection fraction. The best threshold of longitudinal strain for predicting a right ventricular ejection fraction of <40% was -17.0%. Right ventricular longitudinal strain is a powerful method for evaluating patients with tetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.

Does permanent atrial fibrillation modify response to cardiac resynchronization therapy in heart failure patients?

PubMed

Abreu, Ana; Oliveira, Mário; Silva Cunha, Pedro; Santa Clara, Helena; Portugal, Guilherme; Gonçalves Rodrigues, Inês; Santos, Vanessa; Morais, Luís; Selas, Mafalda; Soares, Rui; Branco, Luísa; Ferreira, Rui; Mota Carmo, Miguel

2017-10-01

The benefits of cardiac resynchronization therapy (CRT) documented in heart failure (HF) may be influenced by atrial fibrillation (AF). We aimed to compare CRT response in patients in AF and in sinus rhythm (SR). We prospectively studied 101 HF patients treated by CRT. Rates of clinical, echocardiographic and functional response, baseline NYHA class and variation, left ventricular ejection fraction, volumes and mass, atrial volumes, cardiopulmonary exercise test (CPET) duration (CPET dur), peak oxygen consumption (VO 2 max) and ventilatory efficiency (VE/VCO 2 slope) were compared between AF and SR patients, before and at three and six months after implantation of a CRT device. All patients achieved ≥95% biventricular pacing, and 5.7% underwent atrioventricular junction ablation. Patients were divided into AF (n=35) and SR (n=66) groups; AF patients were older, with larger atrial volumes and lower CPET dur and VO 2 max before CRT. The percentages of clinical and echocardiographic responders were similar in the two groups, but there were more functional responders in the AF group (71% vs. 39% in SR patients; p=0.012). In SR patients, left atrial volume and left ventricular mass were significantly reduced (p=0.015 and p=0.021, respectively), whereas in AF patients, CPET dur (p=0.003) and VO 2 max (p=0.001; 0.083 age-adjusted) showed larger increases. Clinical and echocardiographic response rates were similar in SR and AF patients, with a better functional response in AF. Improvement in left ventricular function and volumes occurred in both groups, but left ventricular mass reduction and left atrial reverse remodeling were seen exclusively in SR patients (ClinicalTrials.gov identifier: NCT02413151; FCT code: PTDC/DES/120249/2010). Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Pleural effusion decreases left ventricular pre-load and causes haemodynamic compromise: an experimental porcine study.

PubMed

Wemmelund, K B; Lie, R H; Juhl-Olsen, P; Frederiksen, C A; Hermansen, J F; Sloth, E

2012-08-01

Although pleural effusion is a common complication in critically ill patients, detailed knowledge is missing about the haemodynamic impact and the underlining mechanisms. The aim of this study was to evaluate the haemodynamic effect of incremental pleural effusion by means of invasive haemodynamic parameters and transthoracic echocardiography. This experimental interventional study was conducted using 22 female piglets (17.5-21.5 kg) randomized for right-side (n = 9) and left-side (n = 9) pleural effusion, or sham operation (n = 4). Pleural effusion was induced by infusing incremental volumes of saline into the pleural cavity. Invasive haemodynamic measurements and echocardiographical images were obtained at baseline, a volume of 45 ml/kg, a volume of 75 ml/kg and 45 min after drainage. No difference (all P > 0.147) was found between right- and left-side pleural effusion, and the groups were thus pooled. At 45 ml/kg cardiac output, mean arterial pressure, stroke volume and mixed venous saturation decreased (all P < 0.003); central venous pressure and pulmonary arterial pressure increased (both P > 0.003) at this point. The changes accelerated at 75 ml/kg. At 45 ml/kg left ventricular pre-load in terms of end-diastolic area decreased significantly (P < 0.001). The effect on haemodynamics and cardiac dimensions changed dramatically at 75 ml/kg. Cardiac output, mean arterial pressure, central venous pressure and left ventricular end-diastolic area returned to normal during a recovery period of 45 min (all P > 0.061). Incremental volumes of unilateral pleural effusion induced a significant haemodynamic impact fully reversible after drainage. Pleural effusion causes a significant decrease of left ventricular pre-load in a diverse picture of haemodynamic compromise. © 2012 The Authors. Acta Anaesthesiologica Scandinavica © 2012 The Acta Anaesthesiologica Scandinavica Foundation.

Left ventricular endocardial surface detection based on real-time 3D echocardiographic data

NASA Technical Reports Server (NTRS)

Corsi, C.; Borsari, M.; Consegnati, F.; Sarti, A.; Lamberti, C.; Travaglini, A.; Shiota, T.; Thomas, J. D.

2001-01-01

OBJECTIVE: A new computerized semi-automatic method for left ventricular (LV) chamber segmentation is presented. METHODS: The LV is imaged by real-time three-dimensional echocardiography (RT3DE). The surface detection model, based on level set techniques, is applied to RT3DE data for image analysis. The modified level set partial differential equation we use is solved by applying numerical methods for conservation laws. The initial conditions are manually established on some slices of the entire volume. The solution obtained for each slice is a contour line corresponding with the boundary between LV cavity and LV endocardium. RESULTS: The mathematical model has been applied to sequences of frames of human hearts (volume range: 34-109 ml) imaged by 2D and reconstructed off-line and RT3DE data. Volume estimation obtained by this new semi-automatic method shows an excellent correlation with those obtained by manual tracing (r = 0.992). Dynamic change of LV volume during the cardiac cycle is also obtained. CONCLUSION: The volume estimation method is accurate; edge based segmentation, image completion and volume reconstruction can be accomplished. The visualization technique also allows to navigate into the reconstructed volume and to display any section of the volume.

Increased gray-matter volume in medication-naive high-functioning children with autism spectrum disorder.

PubMed

Palmen, Saskia J M C; Hulshoff Pol, Hilleke E; Kemner, Chantal; Schnack, Hugo G; Durston, Sarah; Lahuis, Bertine E; Kahn, René S; Van Engeland, Herman

2005-04-01

To establish whether high-functioning children with autism spectrum disorder (ASD) have enlarged brains in later childhood, and if so, whether this enlargement is confined to the gray and/or to the white matter and whether it is global or more prominent in specific brain regions. Brain MRI scans were acquired from 21 medication-naive, high-functioning children with ASD between 7 and 15 years of age and 21 comparison subjects matched for gender, age, IQ, height, weight, handedness, and parental education, but not pubertal status. Patients showed a significant increase of 6% in intracranium, total brain, cerebral gray matter, cerebellum, and of more than 40% in lateral and third ventricles compared to controls. The cortical gray-matter volume was evenly affected in all lobes. After correction for brain volume, ventricular volumes remained significantly larger in patients. High-functioning children with ASD showed a global increase in gray-matter, but not white-matter and cerebellar volume, proportional to the increase in brain volume, and a disproportional increase in ventricular volumes, still present after correction for brain volume. Advanced pubertal development in the patients compared to the age-matched controls may have contributed to the findings reported in the present study.

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

Left atrial enlargement increases the risk of major adverse cardiac events independent of coronary vasodilator capacity.

PubMed

Koh, Angela S; Murthy, Venkatesh L; Sitek, Arkadiusz; Gayed, Peter; Bruyere, John; Wu, Justina; Di Carli, Marcelo F; Dorbala, Sharmila

2015-09-01

Longstanding uncontrolled atherogenic risk factors may contribute to left atrial (LA) hypertension, LA enlargement (LAE) and coronary vascular dysfunction. Together they may better identify risk of major adverse cardiac events (MACE). The aim of this study was to test the hypothesis that chronic LA hypertension as assessed by LAE modifies the relationship between coronary vascular function and MACE. In 508 unselected subjects with a normal clinical (82)Rb PET/CT, ejection fraction ≥40 %, no prior coronary artery disease, valve disease or atrial fibrillation, LAE was determined based on LA volumes estimated from the hybrid perfusion and CT transmission scan images and indexed to body surface area. Absolute myocardial blood flow and global coronary flow reserve (CFR) were calculated. Subjects were systematically followed-up for the primary end-point - MACE - a composite of all-cause death, myocardial infarction, hospitalization for heart failure, stroke, coronary artery disease progression or revascularization. During a median follow-up of 862 days, 65 of the subjects experienced a composite event. Compared with subjects with normal LA size, subjects with LAE showed significantly lower CFR (2.25 ± 0.83 vs. 1.95 ± 0.80, p = 0.01). LAE independently and incrementally predicted MACE even after accounting for clinical risk factors, medication use, stress left ventricular ejection fraction, stress left ventricular end-diastolic volume index and CFR (chi-squared statistic increased from 30.9 to 48.3; p = 0.001). Among subjects with normal CFR, those with LAE had significantly worse event-free survival (risk adjusted HR 5.4, 95 % CI 2.3 - 12.8, p < 0.0001). LAE and reduced CFR are related but distinct cardiovascular adaptations to atherogenic risk factors. LAE is a risk marker for MACE independent of clinical factors and left ventricular volumes; individuals with LAE may be at risk of MACE despite normal coronary vascular function.

Right ventricular function during one-lung ventilation: effects of pressure-controlled and volume-controlled ventilation.

PubMed

Al Shehri, Abdullah M; El-Tahan, Mohamed R; Al Metwally, Roshdi; Qutub, Hatem; El Ghoneimy, Yasser F; Regal, Mohamed A; Zien, Haytham

2014-08-01

To test the effects of pressure-controlled (PCV) and volume-controlled (VCV) ventilation during one-lung ventilation (OLV) for thoracic surgery on right ventricular (RV) function. A prospective, randomized, double-blind, controlled, crossover study. A single university hospital. Fourteen pairs of consecutive patients scheduled for elective thoracotomy. Patients were assigned randomly to ventilate the dependent lung with PCV or VCV mode, each in a randomized crossover order using tidal volume of 6 mL/kg, I: E ratio 1: 2.5, positive end-expiratory pressure (PEEP) of 5 cm H2O and respiratory rate adjusted to maintain normocapnia. Intraoperative changes in RV function (systolic and early diastolic tricuspid annular velocity (TAV), end-systolic volume (ESV), end-diastolic volume (EDV) and fractional area changes (FAC)), airway pressures, compliance and oxygenation index were recorded. The use of PCV during OLV resulted in faster systolic (10.1±2.39 vs. 5.8±1.67 cm/s, respectively), diastolic TAV (9.2±1.99 vs. 4.6±1.42 cm/s, respectively) (p<0.001) and compliance and lower ESV, EDV and airway pressures (p<0.05) than during the use of VCV. Oxygenation indices were similar during the use of VCV and PCV. The use of PCV offers more improved RV function than the use of VCV during OLV for open thoracotomy. These results apply specifically to younger patients with good ventricular and pulmonary functions. © 2014 Elsevier Inc. All rights reserved.

Four-dimensional ultrasonography of the fetal heart using color Doppler spatiotemporal image correlation.

PubMed

Gonçalves, Luís F; Romero, Roberto; Espinoza, Jimmy; Lee, Wesley; Treadwell, Marjorie; Chintala, Kavitha; Brandl, Helmut; Chaiworapongsa, Tinnakorn

2004-04-01

To describe clinical and research applications of 4-dimensional imaging of the fetal heart using color Doppler spatiotemporal image correlation. Forty-four volume data sets were acquired by color Doppler spatiotemporal image correlation. Seven subjects were examined: 4 fetuses without abnormalities, 1 fetus with ventriculomegaly and a hypoplastic cerebellum but normal cardiac anatomy, and 2 fetuses with cardiac anomalies detected by fetal echocardiography (1 case of a ventricular septal defect associated with trisomy 21 and 1 case of a double-inlet right ventricle with a 46,XX karyotype). The median gestational age at the time of examination was 21 3/7 weeks (range, 19 5/7-34 0/7 weeks). Volume data sets were reviewed offline by multiplanar display and volume-rendering methods. Representative images and online video clips illustrating the diagnostic potential of this technology are presented. Color Doppler spatiotemporal image correlation allowed multiplanar visualization of ventricular septal defects, multiplanar display and volume rendering of tricuspid regurgitation, volume rendering of the outflow tracts by color and power Doppler ultrasonography (both in a normal case and in a case of a double-inlet right ventricle with a double-outlet right ventricle), and visualization of venous streams at the level of the foramen ovale. Color Doppler spatiotemporal image correlation has the potential to simplify visualization of the outflow tracts and improve the evaluation of the location and extent of ventricular septal defects. Other applications include 3-dimensional evaluation of regurgitation jets and venous streams at the level of the foramen ovale.

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

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.

Changes in left ventricular ejection fraction and coronary flow reserve after coronary microembolization

PubMed Central

Ma, Jianying; Qian, Juying; Zeng, Xin; Sun, Aijun; Chang, Shufu; Chen, Zhangwei; Zou, Yunzeng

2012-01-01

Introduction Although coronary microembolization (CME) is a frequent phenomenon in patients undergoing percutaneous coronary intervention, few data are available on the changes in left ventricular ejection fraction (LVEF) and coronary flow reserve (CFR) after CME. Material and methods In this study, six miniature swine of either sex (body weight 21-25 kg) were used to prepare a CME model. After coronary angiography, 1.2 × 105 microspheres (42 µm) were selectively infused into the left anterior descending artery via an infusion catheter. Left ventricular ejection fraction was evaluated using transthoracic echocardiography; myocardial blood flow was measured using coloured microspheres; and CFR and coronary pressure were measured using Doppler and a pressure wire. Results Left ventricular ejection fraction was 0.77 ±0.08 at baseline, 0.69 ±0.08 at 2 h, 0.68 ±0.08 at 6 h, and 0.76 ±0.06 at 1 week (2 h vs. baseline p < 0.05; 6 h vs. baseline p < 0.01). After CME, left ventricular end systolic volume (LVESV) and end diastolic volume (LVEDV) were significant larger 1 week later (p < 0.01 for both), while CFR was significantly reduced at 6 h (1.24 ±0.10 at 6 h vs. 1.77 ±0.30 at baseline, p < 0.01) and myocardial blood flow remained unchanged. Serum ET-1 level was significantly higher only at 6 h after CME (6 h vs. baseline p < 0.05). Conclusions Reduction of CFR and LVEF is significant at 6 h after CME and recovers 1 week later with left ventricular dilation. PMID:22457677

MRimaging findings after ventricular puncture in patients with SAH.

PubMed

Tominaga, J; Shimoda, M; Oda, S; Kumasaka, A; Yamazaki, K; Tsugane, R

2001-11-01

Using magnetic resonance (MR) imaging, we studied brain injury from ventricular puncture performed during craniotomy in the acute stage of subarachnoid hemorrhage (SAH). 80 patients underwent craniotomy for aneurysm obliteration within 48 hr after SAH, ventricular puncture for drainage of cerebrospinal fluid (CSF) was performed to reduce intracranial pressure. MR imaging was performed within 3 days following surgery to measure the size of the lesion, and was repeated on postoperative days 14 and 30. Of the 80 patients with ventricular puncture preceding craniotomy, 65 (81%) showed MR evidence of brain injury from the puncture. Overall, 149 lesions were detected. According to coronal images, cortical injuries (54 cases), penetrating injury to tracts along the ventricular tube (55 cases), caudate injury (25 cases), and corpus callosum injury (15 cases). Brain injuries from ventricular puncture did not correlate significantly to patient outcome. While ventricular puncture and drainage of CSF can readily be performed to decrease brain volume at the time of craniotomy in acute-stage SAH, neurosurgeons should be aware of a surprisingly high incidence of brain injury complicating puncture.

Cannula Tip With Integrated Volume Sensor for Rotary Blood Pump Control: Early-Stage Development.

PubMed

Cysyk, Joshua; Newswanger, Ray; Popjes, Eric; Pae, Walter; Jhun, Choon-Sik; Izer, Jenelle; Weiss, William; Rosenberg, Gerson

2018-05-10

The lack of direct measurement of left ventricular unloading is a significant impediment to the development of an automatic speed control system for continuous-flow left ventricular assist devices (cf-LVADs). We have developed an inlet cannula tip for cf-LVADs with integrated electrodes for volume sensing based on conductance. Four platinum-iridium ring electrodes were installed into grooves on a cannula body constructed from polyetheretherketone (PEEK). A sinusoidal current excitation waveform (250 μA pk-pk, 50 kHz) was applied across one pair of electrodes, and the conductance-dependent voltage was sensed across the second pair of electrodes. The conductance catheter was tested in an acute ovine model (n = 3) in conjunction with the HeartMate II rotary blood pump to provide circulatory support and unload the ventricle. Echocardiography was used to measure ventricular size during pump support for verification for the conductance measurements. The conductance measurements correlated linearly with the echocardiography dimension measurements more than the full range of pump support from minimum support to suction. This cannula tip will enable the development of automatic control systems to optimize pump support based on a real-time measurement of ventricular size.

Electrophysiological determinants of arrhythmic susceptibility upon endocardial and epicardial pacing in guinea-pig heart.

PubMed

Osadchii, O E

2012-08-01

Endocardial pacing instituted to treat symptomatic bradycardia may nevertheless promote tachyarrhythmia in some pacemaker-implanted patients. We sought to determine the contributing electrophysiological mechanisms. Left ventricular (LV) monophasic action potential duration (APD(90)) and effective refractory periods were determined in perfused guinea-pig hearts along with volume-conducted ECG recordings during epicardial and endocardial stimulations. Consistent with electrotonic modulation of repolarization, APD(90) at a given (either epicardial or endocardial) recording site tended to be longer while pacing from the ipsilateral LV site as compared to stimulations applied at the opposite side of ventricular wall. As a result, the intrinsic transmural repolarization gradient was amplified during endocardial pacing while being significantly reduced upon epicardial stimulations. The maximum slope of APD(90) restitution was greater upon endocardial than epicardial pacing. The excitability was found to recur at earlier repolarization time point at endocardium than epicardium, thereby contributing to increased endocardial critical intervals for re-excitation. Premature extrasystolic beats could have been elicited at shorter coupling stimulation intervals and propagated with greater transmural conduction delay upon endocardial than epicardial stimulations. Endocardial site exhibited lower ventricular fibrillation thresholds and greater inducibility of tachyarrhythmia upon extrasystolic stimulations as compared to epicardium. Arrhythmic susceptibility in guinea-pig heart is greater during endocardial than epicardial pacing because of greater transmural APD(90) dispersion, steeper electrical restitution slopes, greater critical intervals for LV re-excitation and slower transmural conduction of the earliest premature ectopic beats. Further studies are warranted to determine whether these effects may contribute to proarrhythmia in paced human patients. © 2012 The Author Acta Physiologica © 2012 Scandinavian Physiological Society.

Determinants of kinetic energy of blood flow in the four-chambered heart in athletes and sedentary controls.

PubMed

Steding-Ehrenborg, K; Arvidsson, P M; Töger, J; Rydberg, M; Heiberg, E; Carlsson, M; Arheden, H

2016-01-01

The kinetic energy (KE) of intracardiac blood may play an important role in cardiac function. The aims of the present study were to 1) quantify and investigate the determinants of KE, 2) compare the KE expenditure of intracardiac blood between athletes and control subjects, and 3) quantify the amount of KE inside and outside the diastolic vortex. Fourteen athletes and fourteen volunteers underwent cardiac MRI, including four-dimensional phase-contrast sequences. KE was quantified in four chambers, and energy expenditure was calculated by determining the mean KE/cardiac index. Left ventricular (LV) mass was an independent predictor of diastolic LVKE (R(2) = 0.66, P < 0.001), whereas right ventricular (RV) end-diastolic volume was important for diastolic RVKE (R(2) = 0.76, P < 0.001). The mean KE/cardiac index did not differ between groups (control subjects: 0.53 ± 0.14 mJ·l(-1)·min·m(2) and athletes: 0.56 ± 0.21 mJ·l(-1)·min·m(2), P = 0.98). Mean LV diastolic vortex KE made up 70 ± 1% and 73 ± 2% of total LV diastolic KE in athletes and control subjects (P = 0.18). In conclusion, the characteristics of the LV as a pressure pump and the RV as a volume pump are demonstrated as an association between LVKE and LV mass and between RVKE and end-diastolic volume. This also suggests different filling mechanisms where the LV is dependent on diastolic suction, whereas the RV fills with a basal movement of the atrioventricular plane over "stationary" blood. Both groups had similar energy expenditure for intracardiac blood flow, indicating similar pumping efficiency, likely explained by the lower heart rate that cancels the higher KE per heart beat in athletes. The majority of LVKE is found within the LV diastolic vortex, in contrast to earlier findings. Copyright © 2016 the American Physiological Society.

Minoxidil accelerates heart failure development in rats with ascending aortic constriction.

PubMed

Turcani, M; Jacob, R

1998-06-01

To test the ability of the heart to express characteristic geometric features of concentric and eccentric hypertrophy concurrently, constriction of the ascending aorta was performed in 4-week-old rats. Simultaneously, these rats were treated with an arteriolar dilator minoxidil. An examination 6 weeks after induction of the hemodynamic overload revealed no signs of congestion in systemic or pulmonary circulation in rats with aortic constriction or minoxidil-treated sham-operated rats. The magnitude of hemodynamic overload caused by aortic constriction or minoxidil treatment could be considered as equivalent, because the same enlargement of left ventricular pressure-volume area was necessary to compensate for either pressure or volume overload. Myocardial contractility decreased in rats with aortic constriction, and the compensation was achieved wholly by the marked concentric hypertrophy. Volume overload in minoxidil-treated rats was compensated partially by the eccentric hypertrophy and partially by the increased myocardial contractility. In contrast, increased lung weight and pleural effusion were found in all minoxidil-treated rats with aortic constriction. Unfavorable changes in left ventricular mass and geometry, relatively high chamber stiffness, and depressed ventricular and myocardial function were responsible for the massive pulmonary congestion.

A new shape for an old function: lasting effect of a physiologic surgical restoration of the left ventricle

PubMed Central

Cirillo, Marco; Amaducci, Andrea; Villa, Emmanuel; Tomba, Margherita Dalla; Brunelli, Federico; Mhagna, Zen; Troise, Giovanni; Quaini, Eugenio

2006-01-01

Background Long-term morphofunctional outcome may vary widely in surgical anterior left ventricular wall restoration, suggesting variability in post-surgical remodeling similar to that observed following acute myocardial infarction. The aim of this pilot study was to demonstrate that surgical restoration obtained with a particular shape of endoventricular patch leads to steady morphofunctional ventricular improvement when geometry, volume and residual akinesia can be restored as normal as possible. Methods This study involved 12 consecutive patients with previous anterior myocardial infarction, dilated cardiomyopathy and no mitral procedures, who underwent left ventricular reconstruction and coronary revascularization between May 2002 and May 2003 using a small, narrow, oval patch aiming at a volume ≤ 45 mL/m2 with elliptical shape. Eleven geometric parameters were examined preoperatively and at least 3, 12 and 24 months after the operation by serial echocardiographic studies and evaluated by paired t test taking the time of surgery as a starting point for remodeling. Results All patients were in NYHA class 1 at follow-up. Patch geometry obtained a conical shape of the ventricle with new apex, physiologic rearrangement of functioning myocardial wall and small residual akinesia. Ventricular changes at the four time-points showed that all parameters improved significantly compared to preoperative values (end-diastolic volume = 184.2 ± 23.9 vs 139.9 ± 22.0, p = 0.001; vs 151.0 ± 33.8, p = 0.06; vs 144.9 ± 34.0, p = 0.38; end-systolic volume = 125.7 ± 20.6 vs 75.2 ± 14.1, p = 0.001; vs 82.1 ± 23.9, p = 0,18; vs 77.1 ± 19.4, p = 0.41) without further changes during follow-up except for wall motion score index (2.0 ± 0.2 to 1.7 ± 0.2, to 1.4 ± 0.2, to 1.3 ± 0.2) and percentage of akinesia (30.4 ± 7.5 to 29.3 ± 4.2, to 19.8 ± 11.6, to 14.5 ± 7.2) which slowly and significantly improved suggesting a positive post-surgery remodeling. Conclusion Ventricular reconstruction caring of physiological shape, volume, revascularization and residual akinesia obtained a steady geometry. Positive remodeling and equalization of geometrical outcome may persistently prevent long-term redilation. PMID:17083734

Fibrosis-Related Gene Expression in Single Ventricle Heart Disease.

PubMed

Nakano, Stephanie J; Siomos, Austine K; Garcia, Anastacia M; Nguyen, Hieu; SooHoo, Megan; Galambos, Csaba; Nunley, Karin; Stauffer, Brian L; Sucharov, Carmen C; Miyamoto, Shelley D

2017-12-01

To evaluate fibrosis and fibrosis-related gene expression in the myocardium of pediatric subjects with single ventricle with right ventricular failure. Real-time quantitative polymerase chain reaction was performed on explanted right ventricular myocardium of pediatric subjects with single ventricle disease and controls with nonfailing heart disease. Subjects were divided into 3 groups: single ventricle failing (right ventricular failure before or after stage I palliation), single ventricle nonfailing (infants listed for primary transplantation with normal right ventricular function), and stage III (Fontan or right ventricular failure after stage III). To evaluate subjects of similar age and right ventricular volume loading, single ventricle disease with failure was compared with single ventricle without failure and stage III was compared with nonfailing right ventricular disease. Histologic fibrosis was assessed in all hearts. Mann-Whitney tests were performed to identify differences in gene expression. Collagen (Col1α, Col3) expression is decreased in single ventricle congenital heart disease with failure compared with nonfailing single ventricle congenital heart disease (P = .019 and P = .035, respectively), and is equivalent in stage III compared with nonfailing right ventricular heart disease. Tissue inhibitors of metalloproteinase (TIMP-1, TIMP-3, and TIMP-4) are downregulated in stage III compared with nonfailing right ventricular heart disease (P = .0047, P = .013 and P = .013, respectively). Matrix metalloproteinases (MMP-2, MMP-9) are similar between nonfailing single ventricular heart disease and failing single ventricular heart disease, and between stage III heart disease and nonfailing right ventricular heart disease. There is no difference in the prevalence of right ventricular fibrosis by histology in subjects with single ventricular failure heart disease with right ventricular failure (18%) compared with those with normal right ventricular function (38%). Fibrosis is not a primary contributor to right ventricular failure in infants and young children with single ventricular heart disease. Additional studies are required to understand whether antifibrotic therapies are beneficial in this population. Copyright © 2017 Elsevier Inc. All rights reserved.

MRI, volumetry, 1H spectroscopy, and cerebropetal blood flowmetry in childhood idiopathic anatomic megalencephaly.

PubMed

Koudijs, Suzanne M; van der Grond, Jeroen; Hoogendoorn, Mechteld L C; Hulshoff Pol, Hilleke E; Schnack, Hugo G; Witkamp, Theo D; Gooskens, Rob H J M; van Nieuwenhuizen, Onno; Braun, Kees P J

2006-08-01

To evaluate cerebral abnormalities in childhood idiopathic anatomic megalencephaly (MC) by means of different magnetic resonance (MR) modalities. MRI, volumetry, spectroscopy, and cerebropetal blood flowmetry were performed in six children with idiopathic anatomic MC, and seven volunteers. MRI revealed an increased ventricular system in five of six patients. A thalamic hamartoma was found in one patient and a Chiari I malformation was found in two. Volumetric analysis showed a disproportional increase of ventricular volume but normal subarachnoid cerebrospinal fluid (CSF) volume. Supratentorial volume was disproportionally increased compared to cerebellar volume. Intracranial volume correlated significantly with skull circumference. MR spectroscopy (MRS) N-acetyl aspartate/choline (NAA/Cho) peak ratios in WM were significantly higher in patients than in controls. Choline/creatine (Cho/Cr) peak ratios in WM were significantly lower in patients. Cortical gray matter (GM) MRS ratios were unaltered. Cerebropetal flow was increased in MC, possibly related to increased brain volume. This study reveals associated developmental anomalies for idiopathic anatomic MC. A relative ventriculomegaly was found, which should not be misinterpreted as true hydrocephalus. In contrast to metabolic MC, MRS showed no severe disturbances. Total intracranial volume is correlated to skull circumference and cerebropetal blood flow.

Design of a miniature implantable left ventricular assist device using CAD/CAM technology.

PubMed

Okamoto, Eiji; Hashimoto, Takuya; Mitamura, Yoshinori

2003-01-01

In this study, we developed a new miniature motor-driven pulsatile left ventricular assist device (LVAD) for implantation into a Japanese patient of average build by means of computer-aided design and manufacturing (CAD/CAM) technology. A specially designed miniature ball-screw and a high-performance brushless DC motor were used in an artificial heart actuator to allow miniaturization. A blood pump chamber (stroke volume 55 ml) and an inflow and outflow port were designed by computational fluid dynamics (CFD) analysis. The geometry of the blood pump was evaluated using the value of index of pump geometry (IPG) = (Reynolds shear stress) x (occupied volume) as a quantitative index for optimization. The calculated value of IPG varied from 20.6 Nm to 49.1 Nm, depending on small variations in pump geometry. We determined the optimum pump geometry based on the results of quantitative evaluation using IPG and qualitative evaluation using the flow velocity distribution with blood flow tracking. The geometry of the blood pump that gave lower shear stress had more optimum spiral flow around the diaphragm-housing (D-H) junction. The volume and weight of the new LVAD, made of epoxy resin, is 309 ml and 378 g, but further miniaturization will be possible by improving the geometry of both the blood pump and the back casing. Our results show that our new design method for an implantable LVAD using CAD/CAM promises to improve blood compatibility with greater miniaturization.

Stroke volume obtained by electrical interrogation of the brachial artery: transbrachial electrical bioimpedance velocimetry.

PubMed

Bernstein, Donald P; Henry, Isaac C; Banet, Mathew J; Dittrich, Teri

2012-04-01

The goal of this study is to measure left ventricular stroke volume (SV) from the brachial artery (BA) using electrical bioimpedance. Doppler-derived SV was used for comparison. Twenty-nine healthy adults were recruited for study. Doppler echocardiographic-derived SV was obtained from the product of distal left ventricular outflow tract cross-sectional area and systolic velocity integral. SV from the BA was obtained by transbrachial electrical bioimpedance velocimetry (TBEV). Application of a current field across the left brachium was effected by injection of a constant magnitude, high frequency, low amperage, alternating current. Therein, a static voltage (U(0)) and pulsatile voltage change (ΔU(t)) were measured and converted to their corresponding impedances, Z(0) and ΔZ(t). TBEV-derived SV was obtained by multiplying a square root value of the normalized, acceleration-based, peak first time derivative of ΔZ(t) by a volume conductor and systolic flow time. Inter-method agreement was determined by the Bland-Altman method. To assess the contribution of blood resistivity variations to ΔZ(t), BA diameters were measured at end-diastole and peak systolic expansion. Results indicate that since the BA demonstrates parabolic, laminar flow, with minimal diameter changes, blood resistivity variations are likely responsible for the derived impedance changes. Bland-Altman analysis shows that SV is obtainable by TBEV from healthy humans at rest. © 2012 Institute of Physics and Engineering in Medicine

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.

Pulmonary arterial stiffening in COPD and its implications for right ventricular remodelling.

PubMed

Weir-McCall, Jonathan R; Liu-Shiu-Cheong, Patrick Sk; Struthers, Allan D; Lipworth, Brian J; Houston, J Graeme

2018-02-27

Pulmonary pulse wave velocity (PWV) allows the non-invasive measurement of pulmonary arterial stiffening, but has not previously been assessed in COPD. The aim of the current study was to assess PWV in COPD and its association with right ventricular (RV) remodelling. Fifty-eight participants with COPD underwent pulmonary function tests, 6-min walk test and cardiac MRI, while 21 healthy controls (HCs) underwent cardiac MRI. Thirty-two COPD patients underwent a follow-up MRI to assess for longitudinal changes in RV metrics. Cardiac MRI was used to quantify RV mass, volumes and PWV. Differences in continuous variables between the COPD and HC groups was tested using an independent t-test, and associations between PWV and right ventricular parameters was examined using Pearson's correlation coefficient. Those with COPD had reduced pulsatility (COPD (mean±SD):24.88±8.84% vs. HC:30.55±11.28%, p=0.021), pulmonary acceleration time (COPD:104.0±22.9ms vs. HC: 128.1±32.2ms, p<0.001), higher PWV (COPD:2.62±1.29ms -1 vs. HC:1.78±0.72ms -1 , p=0.001), lower RV end diastolic volume (COPD:53.6±11.1ml vs. HC:59.9±13.0ml, p=0.037) and RV stroke volume (COPD:31.9±6.9ml/m 2 vs. HC:37.1±6.2ml/m 2 , p=0.003) with no difference in mass (p=0.53). PWV was not associated with right ventricular parameters. While pulmonary vascular remodelling is present in COPD, cardiac remodelling favours reduced filling rather than increased afterload. Treatment of obstructive lung disease may have greater effect on cardiac function than treatment of pulmonary vascular disease in most COPD patients KEY POINTS: • Pulmonary pulse wave velocity (PWV) is elevated in COPD. • Pulmonary PWV is not associated with right ventricular remodelling. • Right ventricular remodelling is more in keeping with that of reduced filling.

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.;

Modification of a Volume-Overload Heart Failure Model to Track Myocardial Remodeling and Device-Related Reverse Remodeling

PubMed Central

Tuzun, Egemen; Bick, Roger; Kadipasaoglu, Cihan; Conger, Jeffrey L.; Poindexter, Brian J.; Gregoric, Igor D.; Frazier, O. H.; Towbin, Jeffrey A.; Radovancevic, Branislav

2011-01-01

Purpose. To provide an ovine model of ventricular remodeling and reverse remodeling by creating congestive heart failure (CHF) and then treating it by implanting a left ventricular assist device (LVAD). Methods. We induced volume-overload heart failure in 2 sheep; 20 weeks later, we implanted an LVAD and assessed recovery 11 weeks thereafter. We examined changes in histologic and hemodynamic data and levels of cellular markers of CHF. Results. After CHF induction, we found increases in LV end-diastolic pressure, LV systolic and diastolic dimensions, wall thickness, left atrial diameter, and atrial natriuretic protein (ANP) and endothelin-1 (ET-1) levels; β-adrenergic receptor (BAR) and dystrophin expression decreased markedly. Biopsies confirmed LV remodeling. After LVAD support, LV systolic and diastolic dimensions, wall thickness, and mass, and ANP and ET-1 levels decreased. Histopathologic and hemodynamic markers improved, and BAR and dystrophin expression normalized. Conclusions. We describe a successful sheep model for ventricular and reverse remodeling. PMID:22347659

Evaluation of the interpretative skills of participants of a limited transthoracic echocardiography training course (H.A.R.T.scan course).

PubMed

Royse, C F; Haji, D L; Faris, J G; Veltman, M G; Kumar, A; Royse, A G

2012-05-01

Limited transthoracic echocardiography performed by treating physicians may facilitate assessment of haemodynamic abnormalities in perioperative and critical care patients. The interpretative skills of one hundred participants who completed an education program in limited transthoracic echocardiography were assessed by reporting five pre-recorded case studies. A high level of agreement was observed in ventricular volume assessment (left 95%, right 96%), systolic function (left 99%, right 96%), left atrial pressure (96%) and haemodynamic state (97%). The highest failure to report answers (that is, no answer given) was for right ventricular volume and function. For moderate or severe valve lesions, agreement ranged from 90 to 98%, with failure to report <5% in all cases except for mitral stenosis (18%). For mild valve lesions, the range of agreement was lower (53 to 100%) due to overestimation of severity. Medical practitioners who completed the structured educational program showed good agreement with experts in interpretation of valve and ventricular function.

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.

Measurement of left ventricular mass in vivo using gated nuclear magnetic resonance imaging.

PubMed

Florentine, M S; Grosskreutz, C L; Chang, W; Hartnett, J A; Dunn, V D; Ehrhardt, J C; Fleagle, S R; Collins, S M; Marcus, M L; Skorton, D J

1986-07-01

Alterations of left ventricular mass occur in a variety of congenital and acquired heart diseases. In vivo determination of left ventricular mass, using several different techniques, has been previously reported. Problems inherent in some previous methods include the use of ionizing radiation, complicated geometric assumptions and invasive techniques. We tested the ability of gated nuclear magnetic resonance imaging to determine in vivo left ventricular mass in animals. By studying both dogs (n = 9) and cats (n = 2) of various sizes, a broad range of left ventricular mass (7 to 133 g) was examined. With a 0.5 tesla superconducting nuclear magnetic resonance imaging system the left ventricle was imaged in the transaxial plane and multiple adjacent 10 mm thick slices were obtained. Endocardial and epicardial edges were manually traced in each computer-displayed image. The wall area of each image was determined by computer and the areas were summed and multiplied by the slice thickness and the specific gravity of muscle, providing calculated left ventricular mass. Calculated left ventricular mass was compared with actual postmortem left ventricular mass using linear regression analysis. An excellent relation between calculated and actual mass was found (r = 0.95; SEE = 13.1 g; regression equation: magnetic resonance mass = 0.95 X actual mass + 14.8 g). Intraobserver and interobserver reproducibility were also excellent (r = 0.99). Thus, gated nuclear magnetic resonance imaging can accurately determine in vivo left ventricular mass in anesthetized animals.

M-mode and two-dimensional echocardiographic reference values for three Hungarian dog breeds: Hungarian Vizsla, Mudi and Hungarian Greyhound.

PubMed

Vörös, Károly; Hetyey, Csaba; Reiczigel, Jeno; Czirok, Gábor Nagy

2009-06-01

The aim of the study was to establish normal reference echocardiographic values for three Hungarian dog breeds, and to determine the potential dependence of intracardiac parameters on body weight, age and gender. M-mode and two-dimensional echocardiography were performed on 95 clinically healthy dogs including 45 Hungarian Vizslas, 28 Mudis and 22 Hungarian Greyhounds. Linear intracardiac measurements included interventricular septal thickness (IVS), left ventricular internal diameter (LVID), left ventricular posterior wall thickness (LVPW) both in systole and diastole, as well as left atrial internal diameter (LAD), and aortic diameter (AOD) in early diastole. Fractional shortening (FS), end-diastolic and end-systolic left ventricular volumes (EDV and ESV), as well as LAD:AOD ratio were calculated from the linear parameters. Mean, range and standard deviation of measurements were calculated for each breed. Body weight positively correlated in all three breeds with all left ventricular dimensions, such as IVS d , IVS s , LVID d , LVIDD s , LVPW d and LVPW s parameters. LA values showed positive correlations to body weight in all three breeds. AOD and LA demonstrated a positive correlation with body weight in Hungarian Vizslas and Mudis, whilst the LAD:AOD ratio was related to body weight only in Mudis. Gender did not correlate with any of the measured echocardiographic parameters in any breeds. In Mudis, a positive correlation was found between the LAD: AOD ratio and age, as well as between the LAD: AOD ratio and E point to septal separation (EPSS).

[Effects of trimetazidine on serum oxygen free radicals in congestive heart failure].

PubMed

Ma, Qi-lin; Xie, Yong; Zhang, Sai-dan

2002-12-28

To investigate the level of serum superoxide dismutase (SOD) and maiondialdehyde (MDA) and left ventricular systolic function in congestive heart failure (CHF) and to evaluate the influence of trimetazidine on them. Serum SOD and MDA were measured in 50 patients with heart function from grade two to four and 15 normal subjects. All the persons underwent echocardiography to determine the left ventricular end-systolic volume index (LVESVI) and the left ventricular ejection fraction (EF). The patients with CHF were randomly treated with trimetazidine plus routine therapy (n = 25) or routine therapy only (n = 25) for 8 weeks with evaluations made before and after the treatment. The SOD level and EF in the patients with CHF significantly decreased and the MDA level and LVESVI in those patients significantly increased compared with the normal subjects (P < 0.05); the severer the CHF, the greater the changes. After the treatment, the SOD level and EF increased significantly and MDA and LVESVI decreased significantly (P < 0.01) in both the trimetazidine and the conventional groups. And these changes were more obvious in the trimetazidine group than in the conventional group(P < 0.01). Oxygen free radicals play an important role in the pathophysiologic changes of CHF. The level of serum SOD and MDA can indicate the degree of CHF. Trimetazidine not only increases the level of SOD and decreases the level of MDA, but also improves the left ventricular systolic function.

Reply to the commentary by Hillman et al. on: "Vascular distensibilities have minor effects on intracardiac shunt patterns in reptiles" by Filogonio et al. (2017).

PubMed

Filogonio, Renato; Costa Leite, Cléo Alcantara; Wang, Tobias

2017-06-01

Our meta-analysis (Filogonio et al., 2017) on central vascular blood flows in a snake (Crotalus durissus) and a turtle (Trachemys scripta) was motivated by Hillman et al.'s (2014) analysis on amphibians to investigate whether cardiac shunt patterns depend on cardiac output and vascular distensibilities. In contrast to Hillman et al. (2014), we did not uncover a general trend that supports the notion that cardiac shunts in reptiles are dictated by vascular distensibilities. In addition to our response to the criticism raised by Hillman et al. (2017), we suggest that future experiments should consider (i) both compliance and distensibility of the major arteries; (ii) differences in volume of the systemic and pulmonary circuits to account for the accommodation of stroke volume; and (iii) an evaluation of the pulsatile pressures in both the ventricle and the major arteries to consider the timing of the ventricular ejection provided by opening of the ventricular valves. We hope these suggestions may help future clarification of the relative importance of passive arterial mechanical properties compared to autonomic regulation in determining intracardiac shunts in both amphibians and reptiles. Copyright © 2017 Elsevier GmbH. All rights reserved.

Cardiovascular response to acute normovolemic hemodilution in patients with coronary artery diseases: Assessment with transesophageal echocardiography.

PubMed

Licker, Marc; Ellenberger, Christoph; Sierra, Jorge; Christenson, Jan; Diaper, John; Morel, Denis

2005-03-01

Preoperative acute normovolemic hemodilution induces an increase in circulatory output that is thought to be limited in patients with cardiac diseases. Using multiple-plane transesophageal echocardiography, we investigated the mechanisms of cardiovascular adaptation during acute normovolemic hemodilution in patients with severe coronary artery disease. Prospective case-control study. Operating theater in a university hospital. Consecutive patients treated with beta-blockers, scheduled to undergo coronary artery bypass (n = 50). After anesthesia induction, blood withdrawal and isovolemic exchange with iso-oncotic starch (1:1.15 ratio) to achieve a hematocrit value of 28%. In addition to heart rate and intravascular pressures, echocardiographic recordings were obtained before and after acute normovolemic hemodilution to assess cardiac preload, afterload, and contractility. In a control group, not subjected to acute normovolemic hemodilution, hemodynamic variables remained stable during a 20-min anesthesia period. Following acute normovolemic hemodilution, increases in cardiac stroke volume (+28 +/- 4%; mean +/- sd) were correlated with increases in central venous pressure (+2.0 +/- 1.3 mm Hg; R = .56) and in left ventricular end-diastolic area (+18 +/- 5%, R = .39). The unchanged left ventricular end-systolic wall stress and preload-adjusted maximal power indicated that neither left ventricular afterload nor contractility was affected by acute normovolemic hemodilution. Diastolic left ventricular filling abnormalities (15 of 22 cases) improved in 11 patients and were stable in the remaining four patients. Despite reduction in systemic oxygen delivery (-20.5 +/- 7%, p < .05), there was no evidence for myocardial ischemia (electrocardiogram, left ventricular wall motion abnormalities). In anesthetized patients with coronary artery disease, moderate acute normovolemic hemodilution did not compromise left ventricular systolic and diastolic function. Lowering blood viscosity resulted in increased stroke volume that was mainly related to increased venous return and higher cardiac preload.

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 (

Cardiac structure and function predicts functional decline in the oldest old.

PubMed

Leibowitz, David; Jacobs, Jeremy M; Lande-Stessman, Irit; Gilon, Dan; Stessman, Jochanan

2018-02-01

Background This study examined the association between cardiac structure and function and the deterioration in activities of daily living (ADLs) in an age-homogenous, community-dwelling population of patients born in 1920-1921 over a five-year follow-up period. Design Longitudinal cohort study. Methods Patients were recruited from the Jerusalem Longitudinal Cohort Study, which has followed an age-homogenous cohort of Jerusalem residents born in 1920-1921. Patients underwent home echocardiography and were followed up for five years. Dependence was defined as needing assistance with one or more basic ADL. Standard echocardiographic assessment of cardiac structure and function, including systolic and diastolic function, was performed. Reassessment of ADLs was performed at the five-year follow-up. Results A total of 459 patients were included in the study. Of these, 362 (79%) showed a deterioration in at least one ADL at follow-up. Patients with functional deterioration had a significantly higher left ventricular mass index and left atrial volume with a lower ejection fraction. There was no significant difference between the diastolic parameters the groups in examined. When the data were examined categorically, a significantly larger percentage of patients with functional decline had an abnormal left ventricular ejection fraction and left ventricular hypertrophy. The association between left ventricular mass index and functional decline remained significant in all multivariate models. Conclusions In this cohort of the oldest old, an elevated left ventricular mass index, higher left atrial volumes and systolic, but not diastolic dysfunction, were predictive of functional disability.

Characteristics of Responders to Cardiac Resynchronization Therapy: The Impact of Echocardiographic Left Ventricular Volume

PubMed Central

Park, Mi Young; Altman, Robert K.; Orencole, Mary; Kumar, Prabhat; Parks, Kimberly A.; Heist, Kevin E.; Singh, Jagmeet P.; Picard, Michael H.

2012-01-01

Summary Background One third of patients who receive cardiac resynchronization therapy (CRT) are classified as nonresponders. Characteristics of responders to CRT have been studied in multiple clinical trials. Hypothesis We aimed to examine characteristics of CRT responders in a routine clinical practice. Method One hundred and twenty five patients were examined retrospectively from a multidisciplinary CRT clinic program. Echocardiographic CRT response was defined as a decrease in left ventricular (LV) end systolic volume (ESV) of ≥ 15% and/or absolute increase of 5% in LV ejection fraction (EF) at 6 month visit. Results There were 81 responders and 44 nonresponders. By univariate analyses, female gender, nonischemic cardiomyopathy etiology, baseline QRS duration, the presence of left bundle branch block (LBBB) and left ventricular end-diastolic volume (LVEDV) index predicted CRT response. However, multivariate analysis demonstrated only QRS duration, LBBB and LVEDV index were independent predictors (QRS width: Odd ratio [OR] 1.027, 95% CI 1.004 – 1.050, p = 0.023; LBBB: OR 3.568, 95% CI 1.284 – 9.910, p=0.015; LV EDV index: OR 0.970, 95% CI 0.953 – 0.987, p= 0.001). While female gender and nonischemic etiology were associated with an improved CRT response on univariate analyses, after adjusting for LV volumes, they were not independent predictors. Conclusion QRS width, LBBB and LVEDV index are independent predictors for echocardiographic CRT response. Previously reported differences in CRT response for gender and cardiomyopathy etiology are associated with differences in baseline LV volumes in our clinical practice. PMID:22886700

Effects of depth and chest volume on cardiac function during breath-hold diving.

PubMed

Marabotti, Claudio; Scalzini, Alessandro; Cialoni, Danilo; Passera, Mirko; Ripoli, Andrea; L'Abbate, Antonio; Bedini, Remo

2009-07-01

Cardiac response to breath-hold diving in human beings is primarily characterized by the reduction of both heart rate and stroke volume. By underwater Doppler-echocardiography we observed a "restrictive/constrictive" left ventricular filling pattern compatible with the idea of chest squeeze and heart compression during diving. We hypothesized that underwater re-expansion of the chest would release heart constriction and normalize cardiac function. To this aim, 10 healthy male subjects (age 34.2 +/- 10.4) were evaluated by Doppler-echocardiography during breath-hold immersion at a depth of 10 m, before and after a single maximal inspiration from a SCUBA device. During the same session, all subjects were also studied at surface (full-body immersion) and at 5-m depth in order to better characterize the relationship of echo-Doppler pattern with depth. In comparison to surface immersion, 5-m deep diving was sufficient to reduce cardiac output (P = 0.042) and increase transmitral E-peak velocity (P < 0.001). These changes remained unaltered at a 10-m depth. Chest expansion at 10 m decreased left ventricular end-systolic volume (P = 0.024) and increased left ventricular stroke volume (P = 0.024). In addition, it decreased transmitral E-peak velocity (P = 0.012) and increased deceleration time of E-peak (P = 0.021). In conclusion the diving response, already evident during shallow diving (5 m) did not progress during deeper dives (10 m). The rapid improvement in systolic and diastolic function observed after lung volume expansion is congruous with the idea of a constrictive effect on the heart exerted by chest squeeze.

Effects of heart rate on experimentally produced mitral regurgitation in dogs.

PubMed

Yoran, C; Yellin, E L; Hori, M; Tsujioka, K; Laniado, S; Sonnenblick, E H; Frater, R W

1983-12-01

The effects of increasing heart rate (HR) on the hemodynamics of acute mitral regurgitation (MR) were studied in 8 open-chest dogs. Filling volume, regurgitant volume and stroke volume were calculated from electromagnetic probe measurements of mitral and aortic flows. The left atrial-left ventricular systolic pressure gradient was measured with micromanometers. The calculated effective mitral regurgitant orifice area varied from 10 to 128 mm2, with a consequent regurgitant fraction (regurgitant volume/filling volume) of 24 to 62%. After crushing the sinus node, HR was increased stepwise from 90 to 180 beats/min by atrial pacing while maintaining aortic pressure constant. With increasing HR, filling volume, stroke volume, regurgitant volume and regurgitant time decreased; total cardiac output, forward cardiac output, regurgitant output, systolic pressure gradient, regurgitant fraction and the regurgitant orifice did not change; left ventricular end-diastolic pressure decreased; and left atrial v-wave amplitude increased. These results indicate that in acute experimental MR with a wide spectrum of incompetence, the relative distribution of forward and regurgitant flows did not change with large increases in HR. At rates greater than 150 beats/min the atrial contraction occurs early and increases the amplitude of the left atrial v wave. This may contribute to the severity of pulmonary congestion in patients with MR.

Heart monitoring using left ventricle impedance and ventricular electrocardiography in left ventricular assist device patients.

PubMed

Her, Keun; Ahn, Chi Bum; Park, Sung Min; Choi, Seong Wook

2015-03-21

Patients who develop critical arrhythmia during left ventricular assist device (LVAD) perfusion have a low survival rate. For diagnosis of unexpected heart abnormalities, new heart-monitoring methods are required for patients supported by LVAD perfusion. Ventricular electrocardiography using electrodes implanted in the ventricle to detect heart contractions is unsuitable if the heart is abnormal. Left ventricular impedance (LVI) is useful for monitoring heart movement but does not show abnormal action potential in the heart muscle. To detect detailed abnormal heart conditions, we obtained ventricular electrocardiograms (v-ECGs) and LVI simultaneously in porcine models connected to LVADs. In the porcine models, electrodes were set on the heart apex and ascending aorta for real-time measurements of v-ECGs and LVI. As the carrier current frequency of the LVI was adjusted to 30 kHz, it was easily derived from the original v-ECG signal by using a high-pass filter (cutoff: 10 kHz). In addition, v-ECGs with a frequency band of 0.1 - 120 Hz were easily derived using a low-pass filter. Simultaneous v-ECG and LVI data were compared to detect heart volume changes during the Q-T period when the heart contracted. A new real-time algorithm for comparison of v-ECGs and LVI determined whether the porcine heartbeats were normal or abnormal. Several abnormal heartbeats were detected using the LVADs operating in asynchronous mode, most of which were premature ventricle contractions (PVCs). To evaluate the accuracy of the new method, the results obtained were compared to normal ECG data and cardiac output measured simultaneously using commercial devices. The new method provided more accurate detection of abnormal heart movements. This method can be used for various heart diseases, even those in which the cardiac output is heavily affected by LVAD operation.

Optimized ventricular restraint therapy: adjustable restraint is superior to standard restraint in an ovine model of ischemic cardiomyopathy.

PubMed

Lee, Lawrence S; Ghanta, Ravi K; Mokashi, Suyog A; Coelho-Filho, Otavio; Kwong, Raymond Y; Kwon, Michael; Guan, Jian; Liao, Ronglih; Chen, Frederick Y

2013-03-01

The effects of ventricular restraint level on left ventricular reverse remodeling are not known. We hypothesized that restraint level affects the degree of reverse remodeling and that restraint applied in an adjustable manner is superior to standard, nonadjustable restraint. This study was performed in 2 parts using a model of chronic heart failure in the sheep. In part I, restraint was applied at control (0 mm Hg, n = 3), low (1.5 mm Hg, n = 3), and high (3.0 mm Hg, n = 3) levels with an adjustable and measurable ventricular restraint (AMVR) device. Restraint level was not altered throughout the 2-month treatment period. Serial restraint level measurements and transthoracic echocardiography were performed. In part II, restraint was applied with the AMVR device set at 3.0 mm Hg (n = 6) and adjusted periodically to maintain that level. This was compared with restraint applied in a standard, nonadjustable manner using a mesh wrap (n = 6). All subjects were followed up for 2 months with serial magnetic resonance imaging. In part I, there was greater and earlier reverse remodeling in the high restraint group. In both groups, the rate of reverse remodeling peaked and then declined as the measured restraint level decreased with progression of reverse remodeling. In part II, adjustable restraint resulted in greater reverse remodeling than standard restraint. Left ventricular end diastolic volume decreased by 12.7% (P = .005) with adjustable restraint and by 5.7% (P = .032) with standard restraint. Left ventricular ejection fraction increased by 18.9% (P = .014) and 14.4% (P < .001) with adjustable and standard restraint, respectively. Restraint level affects the rate and degree of reverse remodeling and is an important determinant of therapy efficacy. Adjustable restraint is more effective than nonadjustable restraint in promoting reverse remodeling. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Pulmonary venous flow determinants of left atrial pressure under different loading conditions in a chronic animal model with mitral regurgitation

NASA Technical Reports Server (NTRS)

Yang, Hua; Jones, Michael; Shiota, Takahiro; Qin, Jian Xin; Kim, Yong Jin; Popovic, Zoran B.; Pu, Min; Greenberg, Neil L.; Cardon, Lisa A.; Eto, Yoko;

Significant correlation of P-wave parameters with left atrial volume index and left ventricular diastolic function.

PubMed

Tsai, Wei-Chung; Lee, Kun-Tai; Wu, Ming-Tsang; Chu, Chih-Sheng; Lin, Tsung-Hsien; Hsu, Po-Chao; Su, Ho-Ming; Voon, Wen-Chol; Lai, Wen-Ter; Sheu, Sheng-Hsiung

2013-07-01

The 12-lead electrocardiogram (ECG) is a commonly used tool to access left atrial enlargement, which is a marker of left ventricular diastolic dysfunction (LVDD). The aim of this study was to evaluate any association of the P-wave measurements in ECG with left atrial volume (LAV) index and LVDD. This study enrolled 270 patients. In this study, 4 ECG P-wave parameters corrected by heart rate, that is, corrected P-wave maximum duration (PWdurMaxC), corrected P-wave dispersion (PWdisperC), corrected P-wave area (PWareaC) and corrected mean P-wave duration (meanPWdurC), were measured. LAV and left ventricular diastolic parameters were measured from echocardiography. LVDD was defined as a pseudonormal or restrictive mitral inflow pattern. The 4 P-wave parameters were significantly correlated with the LAV index after adjusting for age, sex, diabetes, hypertension, coronary artery disease, body mass index and diastolic blood pressure in multivariate analysis. The standardized β coefficients of PWdurMaxC, PWdisperC, meanPWdurC and PWareaC were 0.338, 0.298, 0.215 and 0.296, respectively. The 4 P-wave parameters were also significantly correlated with LVDD after multivariate logistic regression analysis. The odds ratios (95% confidence intervals) of PWdurMaxC, PWdisperC, meanPWdurC and PWareaC were 1.03 (1.01-1.04), 1.02 (1.04-1.04), 1.04 (1.02-1.07) and 1.01 (1.00-1.02), respectively. This study demonstrated that PWdurMaxC, PWdisperC, meanPWdurC and PWareaC were important determinants of the LAV index and LVDD. Therefore, screening patients by means of the 12-lead ECG may be helpful in identifying a high-risk group of increased LAV index and LVDD.

Pulmonary function tests do not predict mortality in patients undergoing continuous-flow left ventricular assist device implantation.

PubMed

Bedzra, Edo K S; Dardas, Todd F; Cheng, Richard K; Pal, Jay D; Mahr, Claudius; Smith, Jason W; Shively, Kent; Masri, S Carolina; Levy, Wayne C; Mokadam, Nahush A

2017-12-01

To investigate the effect of pulmonary function testing on outcomes after continuous flow left ventricular assist device implantation. A total of 263 and 239 patients, respectively, had tests of forced expiratory volume in 1 second and diffusing capacity of the lungs for carbon monoxide preoperatively for left ventricular assist device implantations between July 2005 and September 2015. Kaplan-Meier analysis and multivariable Cox regressions were performed to evaluate mortality. Patients were analyzed in a single cohort and across 5 groups. Postoperative intensive care unit and hospital lengths of stay were evaluated with negative binomial regressions. There is no association of forced expiratory volume in 1 second and diffusing capacity of the lungs for carbon monoxide with survival and no difference in mortality at 1 and 3 years between the groups (log rank P = .841 and .713, respectively). Greater values in either parameter were associated with decreased hospital lengths of stay. Only diffusing capacity of the lungs for carbon monoxide was associated with increased intensive care unit length of stay in the group analysis (P = .001). Ventilator times, postoperative pneumonia, reintubation, and tracheostomy rates were similar across the groups. Forced expiratory volume in 1 second and diffusing capacity of the lungs for carbon monoxide are not associated with operative or long-term mortality in patients undergoing continuous flow left ventricular assist device implantation. These findings suggest that these abnormal pulmonary function tests alone should not preclude mechanical circulatory support candidacy. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Passive and active ventricular elastances of the left ventricle

PubMed Central

Zhong, Liang; Ghista, Dhanjoo N; Ng, Eddie YK; Lim, Soo T

2005-01-01

Background Description of the heart as a pump has been dominated by models based on elastance and compliance. Here, we are presenting a somewhat new concept of time-varying passive and active elastance. The mathematical basis of time-varying elastance of the ventricle is presented. We have defined elastance in terms of the relationship between ventricular pressure and volume, as: dP = EdV + VdE, where E includes passive (Ep) and active (Ea) elastance. By incorporating this concept in left ventricular (LV) models to simulate filling and systolic phases, we have obtained the time-varying expression for Ea and the LV-volume dependent expression for Ep. Methods and Results Using the patient's catheterization-ventriculogram data, the values of passive and active elastance are computed. Ea is expressed as: ; Epis represented as: . Ea is deemed to represent a measure of LV contractility. Hence, Peak dP/dt and ejection fraction (EF) are computed from the monitored data and used as the traditional measures of LV contractility. When our computed peak active elastance (Ea,max) is compared against these traditional indices by linear regression, a high degree of correlation is obtained. As regards Ep, it constitutes a volume-dependent stiffness property of the LV, and is deemed to represent resistance-to-filling. Conclusions Passive and active ventricular elastance formulae can be evaluated from a single-beat P-V data by means of a simple-to-apply LV model. The active elastance (Ea) can be used to characterize the ventricle's contractile state, while passive elastance (Ep) can represent a measure of resistance-to-filling. PMID:15707494

[Effects of Losartan on expression of heme oxygenases in volume-overloaded rats with left-to-right shunt].

PubMed

Yuan, Li-Xing; Liu, Han-Min; Li, Mi; Gao, Ju; Zhou, Tong-Fu

2005-09-01

To study the expression of heme oxygenase-1 mRNA and pulmonary remodeling before and after surgical establishment of left-to-right shunt in volume-overloaded SD rats and rats with Losartan intervention. Left-to-right shunt volume-overloaded SD rat models were established by aortocaval shunt operation. Seven rats with shunt were placed on Losartan (Losartan group), 7 rats with but not given Losartan were included in the operation group, and 4 rats after sham operation served as controls. Pulmonary pressure and right ventricular pressure were measured during catheterization. The relative weights ventricles were determined after execution of the rats. Pulmonary vascular remodeling parameters, including percentage arterial wall thickness and percentage muscularized small arteries, were assessed by morphometry. Heme oxygenase-1 (HO-1) mRNA expression and heme oxygenase-2 (HO-2) mRNA expression were detected RT-PCR method. Pulmonary artery pressure and right ventricular relative weight decreased significantly in the rats of Losartan group; in addition, the percentage arterial wall thickness and percentage of muscularized small arteries in the Losartan group were reduced as compared with those in the operation group. The level 1 mRAN expression in rats with shunt was significantly higher than that in rats without shunt. The level mRNA expression in the Losartan group decreased remarkably as compared against that in the operation The level of HO-1 mRNA expression in lungs was significantly higher than that in ventricles. There statistically significant differences in HO-2 mRNA expression levels between the three rat groups. Losartan intervention can markedly reduce pulmonary pressure, inhibit vascular remodeling in volume-overloaded left-to-right shunt rats, and result in down-regulation of HO-1 mRNA expression.

Effects of pressure- or volume-overload hypertrophy on passive stiffness in isolated adult cardiac muscle cells

NASA Technical Reports Server (NTRS)

Kato, S.; Koide, M.; Cooper, G. 4th; Zile, M. R.

1996-01-01

It has been hypothesized that the changes in myocardial stiffness induced by chronic hemodynamic overloading are dependent on changes in the passive stiffness of the cardiac muscle cell (cardiocyte). However, no previous studies have examined the passive constitutive properties of cardiocytes isolated from animals with myocardial hypertrophy. Accordingly, changes in relative passive stiffness of cardiocytes isolated from animals with chronic pressure- or volume-overload hypertrophy were determined by examining the effects of anisosmotic stress on cardiocyte size. Anisosmotic stress was produced by altering superfusate osmolarity. Hypertrophied cardiocytes were enzymatically isolated from 16 adult cats with right ventricular (RV) pressure-overload hypertrophy induced by pulmonary artery banding (PAB) and from 6 adult cats with RV volume-overload hypertrophy induced by creating an atrial septal defect (ASD). Left ventricular (LV) cardiocytes from each cat served as nonhypertrophied, normally loaded, same-animal controls. Superfusate osmolarity was decreased from 305 +/- 3 to 135 +/- 5 mosM and increased to 645 +/- 4 mosM. During anisosmotic stress, there were no significant differences between hypertrophied RV and normal LV cardiocytes in pressure overload PAB cats with respect to percent change in cardiocyte area (47 +/- 2% in RV vs. 48 +/- 2% in LV), diameter (46 +/- 3% in RV vs. 48 +/- 2% in LV), or length (2.4 +/- 0.2% in RV vs. 2.0 +/- 0.3% in LV), or sarcomere length (1.5 +/- 0.1% in RV vs. 1.3 +/- 0.3% in LV). Likewise, there were no significant differences in cardiocyte strain between hypertrophied RV and normal LV cardiocytes from ASD cats. In conclusion, chronic pressure-overload hypertrophy and chronic volume-overload hypertrophy did not alter the cardiocyte response to anisosmotic stress. Thus chronic overload hypertrophy did not alter relative passive cardiocyte stiffness.

Non-invasive magnetic resonance imaging assessment of myocardial changes and the effects of angiotensin-converting enzyme inhibition in diabetic rats

PubMed Central

Al-Shafei, Ahmad I M; Wise, R G; Gresham, G A; Bronns, G; Carpenter, T A; Hall, L D; Huang, Christopher L-H

2002-01-01

A non-invasive cine magnetic resonance imaging (MRI) technique was developed to allow, for the first time, detection and characterization of chronic changes in myocardial tissue volume and the effects upon these of treatment by the angiotensin-converting enzyme (ACE) inhibitor captopril in streptozotocin (STZ)-diabetic male Wistar rats. Animals that had been made diabetic at the ages of 7, 10 and 13 weeks and a captopril-treated group of animals made diabetic at the age of 7 weeks were scanned. The findings were compared with the results from age-matched controls. All animal groups (n = 4 animals in each) were consistently scanned at 16 weeks. Left and right ventricular myocardial volumes were reconstructed from complete data sets of left and right ventricular transverse sections which covered systole and most of diastole using twelve equally incremented time points through the cardiac cycle. The calculated volumes remained consistent through all twelve time points of the cardiac cycle in all five experimental groups and agreed with the corresponding post-mortem determinations. These gave consistent myocardial densities whose values could additionally be corroborated by previous reports, confirming the validity of the quantitative MRI results and analysis. The myocardial volumes were conserved in animals whose diabetes was induced at 13 weeks but were significantly increased relative to body weight in animals made diabetic at 7 and 10 weeks. Captopril treatment, which was started immediately after induction of diabetes, prevented the development of this relative hypertrophy in both the left and right ventricles. We have thus introduced and validated quantitative MRI methods in a demonstration, for the first time, of chronic myocardial changes in both the right and left ventricles of STZ-diabetic rats and their prevention by the ACE inhibitor captopril. PMID:11790818

Disturbed left and right ventricular kinetic energy in patients with repaired tetralogy of Fallot: pathophysiological insights using 4D-flow MRI.

PubMed

Sjöberg, Pia; Bidhult, Sebastian; Bock, Jelena; Heiberg, Einar; Arheden, Håkan; Gustafsson, Ronny; Nozohoor, Shahab; Carlsson, Marcus

2018-04-17

Indications for pulmonary valve replacement (PVR) in patients with pulmonary regurgitation (PR) after repaired tetralogy of Fallot (rToF) are debated. We aimed to compare right (RV) and left ventricular (LV) kinetic energy (KE) measured by 4D-flow magnetic resonance imaging (MRI) in patients to controls, to further understand the pathophysiological effects of PR. Fifteen patients with rToF with PR > 20% and 14 controls underwent MRI. Ventricular volumes and KE were quantified from cine MRI and 4D-flow, respectively. Lagrangian coherent structures were used to discriminate KE in the PR. Restrictive RV physiology was defined as end-diastolic forward flow. LV systolic peak KE was lower in rToF, 2.8 ± 1.1 mJ, compared to healthy volunteers, 4.8 ± 1.1 mJ, p < 0.0001. RV diastolic peak KE was higher in rToF (7.7 ± 4.3 mJ vs 3.1 ± 1.3 mJ, p = 0.0001) and the difference most pronounced in patients with non-restrictive RV physiology. KE was primarily located in the PR volume at the time of diastolic peak KE, 64 ± 17%. This is the first study showing disturbed KE in patients with rToF and PR, in both the RV and LV. The role of KE as a potential early marker of ventricular dysfunction to guide intervention needs to be addressed in future studies. • Kinetic energy (KE) reflects ventricular performance • KE is a potential marker of ventricular dysfunction in Fallot patients • KE is disturbed in both ventricles in patients with tetralogy of Fallot • KE contributes to the understanding of the pathophysiology of pulmonary regurgitation • Lagrangian coherent structures enable differentiation of ventricular inflows.

Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy

PubMed Central

Lanjewar, Swapnil S; Chhabra, Lovely; Chaubey, Vinod K; Joshi, Saurabh; Kulkarni, Ganesh; Kothagundla, Chandrasekhar; Kaul, Sudesh; Spodick, David H

2013-01-01

Background The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration. Methods We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1) were computed and compared between the two subgroups. Results There was no statistically significant difference in qualitative lung function (FEV1) between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy. Conclusion The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration. PMID:24293995

Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy.

PubMed

Lanjewar, Swapnil S; Chhabra, Lovely; Chaubey, Vinod K; Joshi, Saurabh; Kulkarni, Ganesh; Kothagundla, Chandrasekhar; Kaul, Sudesh; Spodick, David H

2013-01-01

The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration. We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1) were computed and compared between the two subgroups. There was no statistically significant difference in qualitative lung function (FEV1) between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy. The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration.

The effect of acute mechanical left ventricular unloading on ovine tricuspid annular size and geometry.

PubMed

Malinowski, Marcin; Wilton, Penny; Khaghani, Asghar; Brown, Michael; Langholz, David; Hooker, Victoria; Eberhart, Lenora; Hooker, Robert L; Timek, Tomasz A

2016-09-01

Left ventricular assist device (LVAD) implantation may alter right ventricular shape and function and lead to tricuspid regurgitation. This in turn has been reported to be a determinant of right ventricular (RV) failure after LVAD implantation, but the effect of mechanical left ventricular (LV) unloading on the tricuspid annulus is unknown. The aim of the study was to provide insight into the effect of LVAD support on tricuspid annular geometry and dynamics that may help to optimize LV unloading with the least deleterious effect on the right-sided geometry. In seven open-chest anaesthetized sheep, nine sonomicrometry crystals were implanted on the right ventricle. Additional nine crystals were implanted around the tricuspid annulus, with one crystal at each commissure defining three separate annular regions: anterior, posterior and septal. Left ventricular unloading was achieved by connecting a cannula in the left atrium and the aorta to a continuous-flow pump. The pump was used for 15 min at a full flow of 3.8 ± 0.3 l/min. Epicardial echocardiography was used to assess the degree of tricuspid insufficiency. Haemodynamic, echocardiographic and sonomicrometry data were collected before and during full unloading. Tricuspid annular area, and the regional and total perimeter were calculated from crystal coordinates, while 3D annular geometry was expressed as the orthogonal distance of each annular crystal to the least squares plane of all annular crystals. There was no significant tricuspid regurgitation observed either before or during LV unloading. Right ventricular free wall to septum diameter increased significantly at end-diastole during unloading from 23.6 ± 5.8 to 26.3 ± 6.5 mm (P = 0.009), but the right ventricular volume, tricuspid annular area and total perimeter did not change from baseline. However, the septal part of the annulus significantly decreased its maximal length (38.6 ± 8.1 to 37.9 ± 8.2 mm, P = 0.03). Annular contraction was not altered. The tricuspid annulus had a complex 3D saddle-shaped geometry that was unaffected during experimental conditions. In healthy sheep hearts, left ventricular unloading increased septal-free wall RV diameter and reduced the length of the septal annulus, without altering the motion or geometry of the tricuspid annulus. Acute left ventricular unloading alone in healthy sheep was not sufficient to significantly perturb tricuspid annular dynamics and result in tricuspid insufficiency. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

A porcine model for acute ischaemic right ventricular dysfunction.

PubMed

Haraldsen, Pernille; Lindstedt, Sandra; Metzsch, Carsten; Algotsson, Lars; Ingemansson, Richard

2014-01-01

To establish an experimental model for acute ischaemic isolated right ventricular dysfunction and the subsequent haemodynamic changes. An open-chest porcine model with ischaemic dysfunction of the right ventricle induced by ligation of the three main branches supporting the right ventricular free wall. Invasive monitoring of mean arterial blood pressure (MAP), central venous pressure (CVP), left atrial pressure (LAP) and right ventricular pressure (RVP); ultrasonic measurement of cardiac output (CO) and calculation of haemodynamic parameters such as stroke volume (SV), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and right ventricular stroke work (RVSW) using standard formulae. The ischaemic challenge to the right ventricle resulted in a significant (≥30%) reduction in RVSW associated with an increase (6-25%) in CVP and reduction (8-18%) in pulmonary artery pressure (PAP) despite unchanged PVR, all reflecting the failing right ventricle. There was also a significant drop in CO (14-22%) despite unchanged LAP indicating lessened transpulmonary delivery of left ventricular preload due to the failing right ventricle causing the haemodynamic compromise rather than left ventricular failure. Supraventricular and ventricular arrhythmias occurred in three and two out of seven pigs, respectively-all of which except one were successfully resuscitated with cardioversion and/or defibrillation. This novel open-chest porcine model of induced ischaemia of the right ventricular free wall resulted in significant haemodynamic compromise confirmed using standard haemodynamic measurements making it useful for further research on acute, ischaemic isolated right ventricular failure.

Design of a right ventricular mock circulation loop as a test bench for right ventricular assist devices.

PubMed

Mueller, Indra; Jansen-Park, So-Hyun; Neidlin, Michael; Steinseifer, Ulrich; Abel, Dirk; Autschbach, Rüdiger; Rossaint, Rolf; Schmitz-Rode, Thomas; Sonntag, Simon Johannes

2017-04-01

Right heart failure (RHF), e.g. due to pulmonary hypertension (PH), is a serious health issue with growing occurrence and high mortality rate. Limited efficacy of medication in advanced stages of the disease constitutes the need for mechanical circulatory support of the right ventricle (RV). An essential contribution to the process of developing right ventricular assist devices (RVADs) is the in vitro test bench, which simulates the hemodynamic behavior of the native circulatory system. To model healthy and diseased arterial-pulmonary hemodynamics in adults (mild and severe PH and RHF), a right heart mock circulation loop (MCL) was developed. Incorporating an anatomically shaped silicone RV and a silicone atrium, it not only enables investigations of hemodynamic values but also suction events or the handling of minimal invasive RVADs in an anatomical test environment. Ventricular pressure-volume loops of all simulated conditions as well as pressure and volume waveforms were recorded and compared to literature data. In an exemplary test, an RVAD was connected to the apex to further test the feasibility of studying such devices with the developed MCL. In conclusion, the hemodynamic behavior of the native system was well reproduced by the developed MCL, which is a useful basis for future RVAD tests.

Tricuspid Regurgitation Does Not Impact Right Ventricular Remodeling After Percutaneous Pulmonary Valve Implantation.

PubMed

Tanase, Daniel; Ewert, Peter; Georgiev, Stanimir; Meierhofer, Christian; Pabst von Ohain, Jelena; McElhinney, Doff B; Hager, Alfred; Kühn, Andreas; Eicken, Andreas

2017-04-10

This study sought to investigate the impact of tricuspid regurgitation (TR) on right ventricular function after percutaneous pulmonary valve implantation (PPVI). PPVI provides a less invasive alternative to surgery in patients with right ventricular-to-pulmonary artery (RV-PA) conduit dysfunction. Recovery of the right ventricle has been described after PPVI for patients with pulmonary stenosis and for those with pulmonary regurgitation. Additional TR enforces RV dysfunction by supplemental volume overload. Limited data are available on the potential of the right ventricle to recover in such a specific hemodynamic situation. In a matched cohort study, we compared patients who underwent PPVI with additional TR with those without TR. The degree of TR improved in 83% of the patients. In our patients (n = 36) exercise capacity and right ventricular volume index improved similarly 6 months after PPVI in patients with and without important TR. None of them had significant TR in the long-term follow-up of median 78 months. PPVI improves not only RV-PA-conduit dysfunction, but also concomitant TR. In patients with a dysfunctional RV-PA conduit and TR, the decision whether to fix TR should be postponed after PPVI. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Enhanced cell volume regulation: a key protective mechanism of ischemic preconditioning in rabbit ventricular myocytes.

PubMed

Diaz, Roberto J; Armstrong, Stephen C; Batthish, Michelle; Backx, Peter H; Ganote, Charles E; Wilson, Gregory J

2003-01-01

Accumulation of osmotically active metabolites, which create an osmotic gradient estimated at ~60 mOsM, and cell swelling are prominent features of ischemic myocardial cell death. This study tests the hypothesis that reduction of ischemic swelling by enhanced cell volume regulation is a key mechanism in the delay of ischemic myocardial cell death by ischemic preconditioning (IPC). Experimental protocols address whether: (i) IPC triggers a cell volume regulation mechanism that reduces cardiomyocyte swelling during subsequent index ischemia; (ii) this reduction in ischemic cell swelling is sufficient in magnitude to account for the IPC protection; (iii) the molecular mechanism that mediates IPC also mediates cell volume regulation. Two experimental models with rabbit ventricular myocytes were studied: freshly isolated pelleted myocytes and 48-h cultured myocytes. Myocytes were preconditioned either by distinct short simulated ischemia (SI)/simulated reperfusion protocols (IPC), or by subjecting myocytes to a pharmacological preconditioning (PPC) protocol (1 microM calyculin A, or 1 microM N(6)-2-(4-aminophenyl)ethyladenosine (APNEA), prior to subjecting them to either different durations of long SI or 30 min hypo-osmotic stress. Cell death (percent blue square myocytes) was monitored by trypan blue staining. Cell swelling was determined by either the bromododecane cell flotation assay (qualitative) or video/confocal microscopy (quantitative). Simulated ischemia induced myocyte swelling in both the models. In pelleted myocytes, IPC or PPC with either calyculin A or APNEA produced a marked reduction of ischemic cell swelling as determined by the cell floatation assay. In cultured myocytes, IPC substantially reduced ischemic cell swelling (P < 0.001). This IPC effect on ischemic cell swelling was related to an IPC and PPC (with APNEA) mediated triggering of cell volume regulatory decrease (RVD). IPC and APNEA also significantly (P < 0.001) reduced hypo-osmotic cell swelling. This IPC and APNEA effect was blocked by either adenosine receptor, PKC or Cl(-) channel inhibition. The osmolar equivalent for IPC protection approximated 50-60 mOsM, an osmotic gradient similar to the estimated ischemic osmotic load for preconditioned and non-preconditioned myocytes. The results suggest that cell volume regulation is a key mechanism that accounts for most of the IPC protection in cardiomyocytes.

Computational analysis of the effect of valvular regurgitation on ventricular mechanics using a 3D electromechanics model.

PubMed

Lim, Ki Moo; Hong, Seung-Bae; Lee, Byong Kwon; Shim, Eun Bo; Trayanova, Natalia

2015-03-01

Using a three-dimensional electromechanical model of the canine ventricles with dyssynchronous heart failure, we investigated the relationship between severity of valve regurgitation and ventricular mechanical responses. The results demonstrated that end-systolic tension in the septum and left ventricular free wall was significantly lower under the condition of mitral regurgitation (MR) than under aortic regurgitation (AR). Stroke work in AR was higher than that in MR. On the other hand, the difference in stroke volume between the two conditions was not significant, indicating that AR may cause worse pumping efficiency than MR in terms of consumed energy and performed work.

Extent of utilization of the Frank-Starling mechanism in conscious dogs. [preload effects on myocardial regulation

NASA Technical Reports Server (NTRS)

Boettcher, D. H.; Vatner, S. F.; Heyndrickx, G. R.; Braunwald, E.

1978-01-01

The left ventricular end-diastolic pressure-dimension relationships in conscious dogs were studied; the ventricle was stressed to its limit in terms of myocardial preload in order to assess the extent of use of the Frank-Starling mechanism under these conditions. The preload was increased through volume loading with saline infusions, the provocation of global myocardial ischemia by constriction of the left main coronary artery, and infusion of methoxamine. While left ventricular end-diastolic pressure increased substantially in the reclining conscious animals, the left ventricular end-diastolic diameter did not increase, suggesting a minimum role for the Frank-Starling mechanism in this case.

Prognostic Factors in Severe Chagasic Heart Failure

PubMed Central

Costa, Sandra de Araújo; Rassi, Salvador; Freitas, Elis Marra da Madeira; Gutierrez, Natália da Silva; Boaventura, Fabiana Miranda; Sampaio, Larissa Pereira da Costa; Silva, João Bastista Masson

2017-01-01

Background Prognostic factors are extensively studied in heart failure; however, their role in severe Chagasic heart failure have not been established. Objectives To identify the association of clinical and laboratory factors with the prognosis of severe Chagasic heart failure, as well as the association of these factors with mortality and survival in a 7.5-year follow-up. Methods 60 patients with severe Chagasic heart failure were evaluated regarding the following variables: age, blood pressure, ejection fraction, serum sodium, creatinine, 6-minute walk test, non-sustained ventricular tachycardia, QRS width, indexed left atrial volume, and functional class. Results 53 (88.3%) patients died during follow-up, and 7 (11.7%) remained alive. Cumulative overall survival probability was approximately 11%. Non-sustained ventricular tachycardia (HR = 2.11; 95% CI: 1.04 - 4.31; p<0.05) and indexed left atrial volume ≥ 72 mL/m2 (HR = 3.51; 95% CI: 1.63 - 7.52; p<0.05) were the only variables that remained as independent predictors of mortality. Conclusions The presence of non-sustained ventricular tachycardia on Holter and indexed left atrial volume > 72 mL/m2 are independent predictors of mortality in severe Chagasic heart failure, with cumulative survival probability of only 11% in 7.5 years. PMID:28443956

Leaflet area as a determinant of tricuspid regurgitation severity in patients with pulmonary hypertension.

PubMed

Afilalo, Jonathan; Grapsa, Julia; Nihoyannopoulos, Petros; Beaudoin, Jonathan; Gibbs, J Simon R; Channick, Richard N; Langleben, David; Rudski, Lawrence G; Hua, Lanqi; Handschumacher, Mark D; Picard, Michael H; Levine, Robert A

2015-05-01

Tricuspid regurgitation (TR) is a risk factor for mortality in pulmonary hypertension (PH). TR severity varies among patients with comparable degrees of PH and right ventricular remodeling. The contribution of leaflet adaptation to the pathophysiology of TR has yet to be examined. We hypothesized that tricuspid leaflet area (TLA) is increased in PH, and that the adequacy of this increase relative to right ventricular remodeling determines TR severity. A prospective cohort of 255 patients with PH from pre and postcapillary pathogeneses was assembled from 2 centers. Patients underwent a 3-dimensional echocardiogram focused on the tricuspid apparatus. TLA was measured with the Omni 4D software package. Compared with normal controls, patients with PH had a 2-fold increase in right ventricular volumes, 62% increase in annular area, and 49% increase in TLA. Those with severe TR demonstrated inadequate increase in TLA relative to the closure area, such that the ratio of TLA:closure area <1.78 was highly predictive of severe TR (odds ratio, 68.7; 95% confidence interval, 16.2-292.7). The median vena contracta width was 8.5 mm in the group with small TLA and large closure area as opposed to 4.8 mm in the group with large TLA and large closure area. TLA plays a significant role in determining which patients with PH develop severe functional TR. The ratio of TLA:closure area, reflecting the balance between leaflet adaptation versus annular dilation and tethering forces, is an indicator of TR severity that may identify which patients stand to benefit from leaflet augmentation during tricuspid valve repair. © 2015 American Heart Association, Inc.

A novel method to estimate safety factor of capture by a fetal micropacemaker.

PubMed

Vest, Adriana Nicholson; Zhou, Li; Bar-Cohen, Yaniv; Eli Loeb, Gerald

2016-07-01

We have developed a rechargeable fetal micropacemaker in order to treat severe fetal bradycardia with comorbid hydrops fetalis, a life-threatening condition in pre-term non-viable fetuses for which there are no effective treatment options. The small size and minimally invasive form factor of our design limit the volume available for circuitry and a power source. The device employs a fixed-rate and fixed-amplitude relaxation oscillator and a tiny, rechargeable lithium ion power cell. For both research and clinical applications, it is valuable to monitor the electrode-myocardium interface in order to determine that adequate pacemaker output is being provided. This is typically accomplished by observing the minimal stimulus strength that achieves threshold for pacing capture. The output of our simple micropacemaker cannot be programmatically altered to determine this minimal capture threshold, but a safety factor can be inferred by determining the refractory period for ventricular capture at a given stimulus strength. This is done by measuring the minimal timing between naturally occurring QRS complexes and pacing stimuli that successfully generate a premature ventricular contraction. The method was tested in a pilot study in four fetal sheep and the data demonstrate that a relative measure of threshold is obtainable. This method provides valuable real-time information about the electrode-tissue interface.

A novel method to estimate safety factor of capture by a fetal micropacemaker

PubMed Central

Vest, Adriana Nicholson; Zhou, Li; Bar-Cohen, Yaniv; Loeb, Gerald Eli

2016-01-01

We have developed a rechargeable fetal micropacemaker in order to treat severe fetal bradycardia with comorbid hydrops fetalis, a life-threatening condition in pre-term non-viable fetuses for which there are no effective treatment options. The small size and minimally invasive form factor of our design limit the volume available for circuitry and a power source. The device employs a fixed-rate and fixed-amplitude relaxation oscillator and a tiny, rechargeable lithium ion power cell. For both research and clinical applications, it is valuable to monitor the electrode-myocardium interface in order to determine that adequate pacemaker output is being provided. This is typically accomplished by observing the minimal stimulus strength that achieves threshold for pacing capture. The output of our simple micropacemaker cannot be programmatically altered to determine this minimal capture threshold, but a safety factor can be inferred by determining the refractory period for ventricular capture at a given stimulus strength. This is done by measuring the minimal timing between naturally occurring QRS complexes and pacing stimuli that successfully generate a premature ventricular contraction. The method was tested in a pilot study in 4 fetal sheep and the data demonstrate that a relative measure of threshold is obtainable. This method provides valuable real-time information about the electrode-tissue interface. PMID:27340134

Fibroblasts and the extracellular matrix in right ventricular disease.

PubMed

Frangogiannis, Nikolaos G

2017-10-01

Right ventricular failure predicts adverse outcome in patients with pulmonary hypertension (PH), and in subjects with left ventricular heart failure and is associated with interstitial fibrosis. This review manuscript discusses the cellular effectors and molecular mechanisms implicated in right ventricular fibrosis. The right ventricular interstitium contains vascular cells, fibroblasts, and immune cells, enmeshed in a collagen-based matrix. Right ventricular pressure overload in PH is associated with the expansion of the fibroblast population, myofibroblast activation, and secretion of extracellular matrix proteins. Mechanosensitive transduction of adrenergic signalling and stimulation of the renin-angiotensin-aldosterone cascade trigger the activation of right ventricular fibroblasts. Inflammatory cytokines and chemokines may contribute to expansion and activation of macrophages that may serve as a source of fibrogenic growth factors, such as transforming growth factor (TGF)-β. Endothelin-1, TGF-βs, and matricellular proteins co-operate to activate cardiac myofibroblasts, and promote synthesis of matrix proteins. In comparison with the left ventricle, the RV tolerates well volume overload and ischemia; whether the right ventricular interstitial cells and matrix are implicated in these favourable responses remains unknown. Expansion of fibroblasts and extracellular matrix protein deposition are prominent features of arrhythmogenic right ventricular cardiomyopathies and may be implicated in the pathogenesis of arrhythmic events. Prevailing conceptual paradigms on right ventricular remodelling are based on extrapolation of findings in models of left ventricular injury. Considering the unique embryologic, morphological, and physiologic properties of the RV and the clinical significance of right ventricular failure, there is a need further to dissect RV-specific mechanisms of fibrosis and interstitial remodelling. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Bivariate Heritability of Total and Regional Brain Volumes: the Framingham Study

PubMed Central

DeStefano, Anita L.; Seshadri, Sudha; Beiser, Alexa; Atwood, Larry D.; Massaro, Joe M.; Au, Rhoda; Wolf, Philip A.; DeCarli, Charles

2009-01-01

Heritability and genetic and environmental correlations of total and regional brain volumes were estimated from a large, generally healthy, community-based sample, to determine if there are common elements to the genetic influence of brain volumes and white matter hyperintensity volume. There were 1538 Framingham Heart Study participants with brain volume measures from quantitative magnetic resonance imaging (MRI) who were free of stroke and other neurological disorders that might influence brain volumes and who were members of families with at least two Framingham Heart Study participants. Heritability was estimated using variance component methodology and adjusting for the components of the Framingham stroke risk profile. Genetic and environmental correlations between traits were obtained from bivariate analysis. Heritability estimates ranging from 0.46 to 0.60, were observed for total brain, white matter hyperintensity, hippocampal, temporal lobe, and lateral ventricular volumes. Moderate, yet significant, heritability was observed for the other measures. Bivariate analyses demonstrated that relationships between brain volume measures, except for white matter hyperintensity, reflected both moderate to strong shared genetic and shared environmental influences. This study confirms strong genetic effects on brain and white matter hyperintensity volumes. These data extend current knowledge by showing that these two different types of MRI measures do not share underlying genetic or environmental influences. PMID:19812462

Segmentation of real-time three-dimensional ultrasound for quantification of ventricular function: a clinical study on right and left ventricles.

PubMed

Angelini, Elsa D; Homma, Shunichi; Pearson, Gregory; Holmes, Jeffrey W; Laine, Andrew F

2005-09-01

Among screening modalities, echocardiography is the fastest, least expensive and least invasive method for imaging the heart. A new generation of three-dimensional (3-D) ultrasound (US) technology has been developed with real-time 3-D (RT3-D) matrix phased-array transducers. These transducers allow interactive 3-D visualization of cardiac anatomy and fast ventricular volume estimation without tomographic interpolation as required with earlier 3-D US acquisition systems. However, real-time acquisition speed is performed at the cost of decreasing spatial resolution, leading to echocardiographic data with poor definition of anatomical structures and high levels of speckle noise. The poor quality of the US signal has limited the acceptance of RT3-D US technology in clinical practice, despite the wealth of information acquired by this system, far greater than with any other existing echocardiography screening modality. We present, in this work, a clinical study for segmentation of right and left ventricular volumes using RT3-D US. A preprocessing of the volumetric data sets was performed using spatiotemporal brushlet denoising, as presented in previous articles Two deformable-model segmentation methods were implemented in 2-D using a parametric formulation and in 3-D using an implicit formulation with a level set implementation for extraction of endocardial surfaces on denoised RT3-D US data. A complete and rigorous validation of the segmentation methods was carried out for quantification of left and right ventricular volumes and ejection fraction, including comparison of measurements with cardiac magnetic resonance imaging as the reference. Results for volume and ejection fraction measurements report good performance of quantification of cardiac function on RT3-D data compared with magnetic resonance imaging with better performance of semiautomatic segmentation methods than with manual tracing on the US data.

A modified Glenn shunt reduces right ventricular stroke work during left ventricular assist device therapy.

PubMed

Schiller, Petter; Vikholm, Per; Hellgren, Laila

2016-03-01

Right ventricular (RV) failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) placement and remains hard to predict. We hypothesized that partial surgical exclusion of the RV with a modified Glenn shunt during LVAD treatment would reduce RV stroke work. An LVAD was implanted in eight pigs and a modified Glenn shunt was constructed. A conductance pressure-volume catheter was placed in the right ventricle through the apex. Haemodynamic data and pressure-volume loops were obtained at the following time periods: (i) baseline, (ii) open shunt, (iii) LVAD with closed shunt and (iii) LVAD and open shunt. During LVAD therapy, the right atrial (RA) pressure increased from 9 mmHg (9-9) to 15 mmHg (12-15), P = 0.01. RV stroke volume increased from 30 ml (29-40) to 51 ml (42-53), P < 0.01. Also, RV stroke work increased to 708 mmHg ml (654-1193) from 535 mmHg ml (424-717), P = 0.04, compared with baseline. During LVAD therapy in combination with a Glenn shunt, the RA pressure decreased from 15 mmHg (12-15) to 10 mmHg (7-11) when compared with LVAD therapy only, P = 0.01. A decrease in RV stroke work from 708 mmHg ml (654-1193) to 465 mmHg ml (366-711), P = 0.04, was seen when the LVAD was combined with a shunt, not significantly different from the baseline value (535 mmHg ml). The developed pressure in the right ventricle decreased from 29 mmHg (26-32) to 21 mmHg (20-24), P < 0.01. The pressure-volume loops of the RV show a significant reduction of RV stroke work during the use of the shunt with LVAD treatment. A modified Glenn shunt reduced RV volumes, RV stroke work and RA pressure during LVAD therapy in an experimental model of heart failure in pigs. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Multi-views Fusion CNN for Left Ventricular Volumes Estimation on Cardiac MR Images.

PubMed

Luo, Gongning; Dong, Suyu; Wang, Kuanquan; Zuo, Wangmeng; Cao, Shaodong; Zhang, Henggui

2017-10-13

Left ventricular (LV) volumes estimation is a critical procedure for cardiac disease diagnosis. The objective of this paper is to address direct LV volumes prediction task. In this paper, we propose a direct volumes prediction method based on the end-to-end deep convolutional neural networks (CNN). We study the end-to-end LV volumes prediction method in items of the data preprocessing, networks structure, and multi-views fusion strategy. The main contributions of this paper are the following aspects. First, we propose a new data preprocessing method on cardiac magnetic resonance (CMR). Second, we propose a new networks structure for end-to-end LV volumes estimation. Third, we explore the representational capacity of different slices, and propose a fusion strategy to improve the prediction accuracy. The evaluation results show that the proposed method outperforms other state-of-the-art LV volumes estimation methods on the open accessible benchmark datasets. The clinical indexes derived from the predicted volumes agree well with the ground truth (EDV: R=0.974, RMSE=9.6ml; ESV: R=0.976, RMSE=7.1ml; EF: R=0.828, RMSE =4.71%). Experimental results prove that the proposed method has high accuracy and efficiency on LV volumes prediction task. The proposed method not only has application potential for cardiac diseases screening for large-scale CMR data, but also can be extended to other medical image research fields.

Resistance Training Regulates Cardiac Function through Modulation of miRNA-214

PubMed Central

Melo, Stéphano Freitas Soares; Barauna, Valério Garrone; Júnior, Miguel Araújo Carneiro; Bozi, Luiz Henrique Marchesi; Drummond, Lucas Rios; Natali, Antônio José; de Oliveira, Edilamar Menezes

2015-01-01

Aims: To determine the effects of resistance training (RT) on the expression of microRNA (miRNA)-214 and its target in sarcoplasmic reticulum Ca2+-ATPase (SERCA2a), and on the morphological and mechanical properties of isolated left ventricular myocytes. Main methods: Male Wistar rats were divided into two groups (n = 7/group): Control (CO) or trained (TR). The exercise-training protocol consisted of: 4 × 12 bouts, 5×/week during 8 weeks, with 80% of one repetition maximum. Key findings: RT increased the left ventricular myocyte width by 15% and volume by 12%, compared with control animals (p < 0.05). The time to half relaxation and time to peak were 8.4% and 4.4% lower, respectively, in cells from TR group as compared to CO group (p < 0.05). RT decreased miRNA-214 level by 18.5% while its target SERCA2a expression were 18.5% higher (p < 0.05). Significance: Our findings showed that RT increases single left ventricular myocyte dimensions and also leads to faster cell contraction and relaxation. These mechanical adaptations may be related to the augmented expression of SERCA2a which, in turn, may be associated with the epigenetic modification of decreased miRNA-214 expression. PMID:25822872

Adolescents who were born very preterm have decreased brain volumes.

PubMed

Nosarti, Chiara; Al-Asady, Mazin H S; Frangou, Sophia; Stewart, Ann L; Rifkin, Larry; Murray, Robin M

2002-07-01

Infants born very preterm have an increased risk of brain injury. Given the great increase in the number of such infants that are surviving, it is important to establish whether any resultant brain abnormalities persist into adolescence and adult life. We therefore examined in vivo whole brain, grey matter, white matter and hippocampal volumes, ventricular size and grey/white matter ratios in a series of adolescents who had been born very preterm, and an age-matched full-term control group. Structural MRI was carried out on a cohort of 72 adolescents (mean age 15 years) who were born before 33 weeks, and 48 age-matched full-term controls. Brain measurements were made blind to group affiliation using stereological principles. After controlling for gender and height, the very preterm subjects showed a 6.0% decrease in whole brain volume, and an 11.8% decrease in cortical grey matter volume, as well as a 15.6% decrease in right and a 12.1% decrease in left hippocampal volumes; they also had a 42.0% increase in the size of the lateral ventricles. Therefore, individuals who were born very preterm continue to show noticeable decrements in brain volumes and striking increases in lateral ventricular volume into adolescence. The functional significance of these abnormalities merits further investigation.

Pressure-controlled drainage of cerebrospinal fluid: clinical experience with a new type of ventricular catheter (Ventcontrol MTC)and an integrated Piezo-resistive sensor at its tip: technical note.

PubMed

Piek, J; Raes, P

1996-01-01

We described a new ventricular catheter that is the combination of a "classic" ventricular catheter with a piezo-resistive transducer at its tip. The device allows parallel recordings of intraventricular fluid pressure via a chip and a fluid-filled external transducer, drainage of cerebrospinal fluid from the ventricle or injection of fluid into the ventricle with simultaneous monitoring of intracranial pressure, and recording of brain tissue pressure in cases of misplacement or dislocation of the ventricular catheter or in cases of progressively narrowing ventricles caused by brain edema. Clinical tests in various situations at different pressure ranges (total recording time, 1356 h in 13 patients) gave excellent correlations of both pressures. Application of the device is especially indicated in clinical situations in which pressure-controlled drainage is desirable, occlusion of ventricular bolts is likely, or pressure-volume tests are needed.

Magnetic resonance imaging analysis of cardiac cycle events in diabetic rats: the effect of angiotensin-converting enzyme inhibition

PubMed Central

Al-Shafei, Ahmad I M; Wise, R G; Gresham, G A; Carpenter, T A; Hall, L D; Huang, Christopher L-H

2002-01-01

Non-invasive magnetic resonance imaging (MRI) was used to characterize changes in left and right ventricular cardiac cycles following induction of experimental, streptozotocin (STZ)-induced, diabetes in male Wistar rats at different ages. The effects of the angiotensin-converting enzyme (ACE) inhibitor captopril upon such chronic physiological changes were then evaluated, also for the first time. Diabetes was induced at the age of 7 weeks in two experimental groups, of which one group was subsequently maintained on captopril (2 g l−1)-containing drinking water, and at 10 and 13 weeks in two further groups. The fifth group provided age-matched controls. All groups (each n = 4 animals) were scanned consistently at 16 weeks, in parallel with timings used in earlier studies that employed this experimental model. Cine magnetic resonance (MR) image acquisition provided transverse sections through both ventricles at twelve time points covering systole and most of diastole. These yielded reconstructions of cardiac anatomy used to derive critical functional indices and their dependence upon time following the triggering electrocardiographic R waves. The left and right ventricular end-diastolic (EDV), end-systolic (ESV) and stroke volumes (SV), and ejection fractions (EF) calculated from each, control and experimental, group showed matching values. This confirmed a necessary condition requiring balanced right and left ventricular outputs and further suggested that STZ-induced diabetes produced physiological changes in both ventricles. Absolute left and right ventricular SVs were significantly altered in all diabetic animals; EDVs and EFs significantly altered in animals diabetic from 7 and 10 but not 13 weeks. When normalized to body weight, left and right ventricular SVs had significantly altered in animals diabetic from 7 and 10 weeks but not 13 weeks. Normalized left ventricular EDVs were also significantly altered in animals diabetic from 7 and 10 weeks. However, normalized right ventricular EDVs were significantly altered only in animals made diabetic from 7 weeks. Diabetic hearts showed major kinetic changes in left and right ventricular contraction (ejection) and relaxation (filling). Both the initial rates of volume change (dV/dt) in both ventricles and the plots of dV/dt values through the cardiac cycle demonstrated more gradual developments of tension during systole and relaxation during diastole. Estimates of the derived left ventricular performance parameters of cardiac output, cardiac power output and stroke work in control animals were comparable with human values when normalized to both body (or cardiac) weight and heart rate. All deteriorated with diabetes. Comparisons of experimental groups diabetic from 7 weeks demonstrated that captopril treatment relieved the alterations in critical volumes, dependence of SV upon EDV, kinetics of systolic contraction and diastolic relaxation and in the derived indicators of ventricular performance. This study represents the first demonstration using non-invasive MRI of early, chronic changes in diastolic filling and systolic ejection in both the left and the right ventricles and of their amelioration by ACE inhibition following STZ-induction of diabetes in intact experimental animals. PMID:11790819

Chronic ovine evaluation of a totally implantable electrical left ventricular assist system.

PubMed

Ramasamy, N; Chen, H; Miller, P J; Jassawalla, J S; Greene, B A; Ocampo, A; Siegel, L C; Oyer, P E; Portner, P M

1989-01-01

The totally implantable Novacor left ventricular assist system (LVAS) comprises a pump/drive unit (VAD), electronic control and power subsystem (ECP), variable volume compensator (VVC), and belt skin transformer (BST). The system is now undergoing chronic in vivo evaluation. Cumulative animal testing of VAD, VVC, and BST subsystems are 12.1, 4.9, and 43 years, respectively. The longest implants were 279 days for the VAD, 767 days for the VVC, and 1,148 days for the BST. A chronic implant of the total system was electively terminated at 260 days. The LVAS was powered via the BST. Continuously monitored hemodynamic and pump parameters have demonstrated normal hemodynamics and LVAS operation. Periodic VVC determinations suggest a 0.8 ml/day diffusive gas loss. Tether-free operation has been demonstrated with an Ag-Zn battery backpack. The animal was healthy and free of infection as indicated by routine hematologic, biochemical and serum enzyme determinations. Hemolysis is minimal (plasma free hemoglobin less than 5 mg%). Pump output ranged from 7 to 8 L/min. Severe valve calcification was the reason for elective termination at 260 days. This preclinical in vivo experience, and in vitro reliability studies, demonstrate efficacy of the total system.

Doppler-derived myocardial systolic strain rate is a strong index of left ventricular contractility

NASA Technical Reports Server (NTRS)

Greenberg, Neil L.; Firstenberg, Michael S.; Castro, Peter L.; Main, Michael; Travaglini, Agnese; Odabashian, Jill A.; Drinko, Jeanne K.; Rodriguez, L. Leonardo; Thomas, James D.; Garcia, Mario J.

2002-01-01

BACKGROUND: Myocardial fiber strain is directly related to left ventricular (LV) contractility. Strain rate can be estimated as the spatial derivative of velocities (dV/ds) obtained by tissue Doppler echocardiography (TDE). The purposes of the study were (1) to determine whether TDE-derived strain rate may be used as a noninvasive, quantitative index of contractility and (2) to compare the relative accuracy of systolic strain rate against TDE velocities alone. METHODS AND RESULTS: TDE color M-mode images of the interventricular septum were recorded from the apical 4-chamber view in 7 closed-chest anesthetized mongrel dogs during 5 different inotropic stages. Simultaneous LV volume and pressure were obtained with a combined conductance-high-fidelity pressure catheter. Peak elastance (Emax) was determined as the slope of end-systolic pressure-volume relationships during caval occlusion and was used as the gold standard of LV contractility. Peak systolic TDE myocardial velocities (Sm) and peak (epsilon'(p)) and mean (epsilon'(m)) strain rates obtained at the basal septum were compared against Emax by linear regression. Emax as well as TDE systolic indices increased during inotropic stimulation with dobutamine and decreased with the infusion of esmolol. A stronger association was found between Emax and epsilon'(p) (r=0.94, P<0.01, y=0.29x+0.46) and epsilon'(m) (r=0.88, P<0.01) than for Sm (r=0.75, P<0.01). CONCLUSIONS: TDE-derived epsilon'(p) and epsilon'(m) are strong noninvasive indices of LV contractility. These indices appear to be more reliable than S(m), perhaps by eliminating translational artifact.

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.

Closing the loop: modelling of heart failure progression from health to end-stage using a meta-analysis of left ventricular pressure-volume loops.

PubMed

Warriner, David R; Brown, Alistair G; Varma, Susheel; Sheridan, Paul J; Lawford, Patricia; Hose, David R; Al-Mohammad, Abdallah; Shi, Yubing

2014-01-01

The American Heart Association (AHA)/American College of Cardiology (ACC) guidelines for the classification of heart failure (HF) are descriptive but lack precise and objective measures which would assist in categorising such patients. Our aim was two fold, firstly to demonstrate quantitatively the progression of HF through each stage using a meta-analysis of existing left ventricular (LV) pressure-volume (PV) loop data and secondly use the LV PV loop data to create stage specific HF models. A literature search yielded 31 papers with PV data, representing over 200 patients in different stages of HF. The raw pressure and volume data were extracted from the papers using a digitising software package and the means were calculated. The data demonstrated that, as HF progressed, stroke volume (SV), ejection fraction (EF%) decreased while LV volumes increased. A 2-element lumped parameter model was employed to model the mean loops and the error was calculated between the loops, demonstrating close fit between the loops. The only parameter that was consistently and statistically different across all the stages was the elastance (Emax). For the first time, the authors have created a visual and quantitative representation of the AHA/ACC stages of LVSD-HF, from normal to end-stage. The study demonstrates that robust, load-independent and reproducible parameters, such as elastance, can be used to categorise and model HF, complementing the existing classification. The modelled PV loops establish previously unknown physiological parameters for each AHA/ACC stage of LVSD-HF, such as LV elastance and highlight that it this parameter alone, in lumped parameter models, that determines the severity of HF. Such information will enable cardiovascular modellers with an interest in HF, to create more accurate models of the heart as it fails.

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.

A multi-scale cardiovascular system model can account for the load-dependence of the end-systolic pressure-volume relationship

PubMed Central

2013-01-01

Background The end-systolic pressure-volume relationship is often considered as a load-independent property of the heart and, for this reason, is widely used as an index of ventricular contractility. However, many criticisms have been expressed against this index and the underlying time-varying elastance theory: first, it does not consider the phenomena underlying contraction and second, the end-systolic pressure volume relationship has been experimentally shown to be load-dependent. Methods In place of the time-varying elastance theory, a microscopic model of sarcomere contraction is used to infer the pressure generated by the contraction of the left ventricle, considered as a spherical assembling of sarcomere units. The left ventricle model is inserted into a closed-loop model of the cardiovascular system. Finally, parameters of the modified cardiovascular system model are identified to reproduce the hemodynamics of a normal dog. Results Experiments that have proven the limitations of the time-varying elastance theory are reproduced with our model: (1) preload reductions, (2) afterload increases, (3) the same experiments with increased ventricular contractility, (4) isovolumic contractions and (5) flow-clamps. All experiments simulated with the model generate different end-systolic pressure-volume relationships, showing that this relationship is actually load-dependent. Furthermore, we show that the results of our simulations are in good agreement with experiments. Conclusions We implemented a multi-scale model of the cardiovascular system, in which ventricular contraction is described by a detailed sarcomere model. Using this model, we successfully reproduced a number of experiments that have shown the failing points of the time-varying elastance theory. In particular, the developed multi-scale model of the cardiovascular system can capture the load-dependence of the end-systolic pressure-volume relationship. PMID:23363818

Levosimendan Prevents Pressure-Overload-induced Right Ventricular Failure.

PubMed

Hillgaard, Thomas Krarup; Andersen, Asger; Andersen, Stine; Vildbrad, Mads D; Ringgaard, Steffen; Nielsen, Jan M; Nielsen-Kudsk, Jens E

2016-04-01

We investigated if chronic levosimendan treatment can prevent and revert pressure-overload-induced right ventricular hypertrophy and failure in rats. Right ventricular hypertrophy and failure was induced in Wistar rats by pulmonary trunk banding (PTB). The PTB rats were treated with levosimendan (3 mg·kg·d) 3 days before surgery [n = 10, prevention (PREV)], 3 weeks after surgery [n = 10, reversal (REV)] or vehicle (n = 10, VEH). Sham-operated rats received vehicle (n = 16, SHAM). Right ventricular function was evaluated 7 weeks after surgery by echocardiography, magnetic resonance imaging, pressure-volume relations, gross anatomy, and histology. PTB induced right ventricular hypertrophy and compensated heart failure evident by reduced cardiac index (CI) without extra cardiac signs of heart failure. Levosimendan treatment prevented deterioration of right ventricular function measured by CI and right ventricular ejection fraction (RVEF) (CI: VEH vs. PREV 281 ± 17 vs. 362 ± 34 mL·min·kg, P ≤ 0.05, RVEF: VEH vs. PREV 57 ± 2% vs. 68 ± 3%, P ≤ 0.01) to values similar to SHAM (CI: 345 ± 21 mL·min·kg, RVEF: 71 ± 2%). RV contractility was improved in the REV group measured by preload recruitable stroke work (VEH vs. REV 39 ± 3 vs. 66 ± 10 mmHg P ≤ 0.05). Chronic treatment with levosimendan prevents the development of right ventricular failure and improves contractility in established pressure-overload-induced right ventricular failure.

Comparison of Gated SPECT Myocardial Perfusion Imaging with Echocardiography for the Measurement of Left Ventricular Volumes and Ejection Fraction in Patients With Severe Heart Failure

PubMed Central

Shojaeifard, Maryam; Ghaedian, Tahereh; Yaghoobi, Nahid; Malek, Hadi; Firoozabadi, Hasan; Bitarafan-Rajabi, Ahmad; Haghjoo, Majid; Amin, Ahmad; Azizian, Nasrin; Rastgou, Feridoon

2015-01-01

Background: Gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is known as a feasible tool for the measurement of left ventricular ejection fraction (EF) and volumes, which are of great importance in the management and follow-up of patients with coronary artery diseases. However, considering the technical shortcomings of SPECT in the presence of perfusion defect, the accuracy of this method in heart failure patients is still controversial. Objectives: The aim of the present study was to compare the results from gated SPECT MPI with those from echocardiography in heart failure patients to compare echocardiographically-derived left ventricular dimension and function data to those from gated SPECT MPI in heart failure patients. Patients and Methods: Forty-one patients with severely reduced left ventricular systolic function (EF ≤ 35%) who were referred for gated SPECT MPI were prospectively enrolled. Quantification of EF, end-diastolic volume (EDV), and end-systolic volume (ESV) was performed by using quantitative gated spect (QGS) (QGS, version 0.4, May 2009) and emory cardiac toolbox (ECTb) (ECTb, revision 1.0, copyright 2007) software packages. EF, EDV, and ESV were also measured with two-dimensional echocardiography within 3 days after MPI. Results: A good correlation was found between echocardiographically-derived EF, EDV, and ESV and the values derived using QGS (r = 0.67, r = 0.78, and r = 0.80 for EF, EDV, and ESV, respectively; P < 0.001) and ECTb (r = 0.68, 0.79, and r = 0.80 for EF, EDV, and ESV, respectively; P < 0.001). However, Bland-Altman plots indicated significantly different mean values for EF, 11.4 and 20.9 using QGS and ECTb, respectively, as compared with echocardiography. ECTb-derived EDV was also significantly higher than the EDV measured with echocardiography and QGS. The highest correlation between echocardiography and gated SPECT MPI was found for mean values of ESV different. Conclusions: Gated SPECT MPI has a good correlation with echocardiography for the measurement of left ventricular EF, EDV, and ESV in patients with severe heart failure. However, the absolute values of these functional parameters from echocardiography and gated SPECT MPI measured with different software packages should not be used interchangeably. PMID:26889455

Assessment of valve haemodynamics, reverse ventricular remodelling and myocardial fibrosis following transcatheter aortic valve implantation compared to surgical aortic valve replacement: a cardiovascular magnetic resonance study

PubMed Central

Fairbairn, Timothy A; Steadman, Christopher D; Mather, Adam N; Motwani, Manish; Blackman, Daniel J; Plein, Sven; McCann, Gerry P; Greenwood, John P

2013-01-01

Objective To compare the effects of transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) on aortic valve haemodynamics, ventricular reverse remodelling and myocardial fibrosis (MF) by cardiovascular magnetic resonance (CMR) imaging. Design A 1.5 T CMR scan was performed preoperatively and 6 months postoperatively. Setting University hospitals of Leeds and Leicester, UK. Patients 50 (25 TAVI, 25 SAVR; age 77±8 years) high-risk severe symptomatic aortic stenosis (AS) patients. Main outcome measures Valve haemodynamics, ventricular volumes, ejection fraction (EF), mass and MF. Results Patients were matched for gender and AS severity but not for age (80±6 vs 73±7 years, p=0.001) or EuroSCORE (22±14 vs 7±3, p<0.001). Aortic valve mean pressure gradient decreased to a greater degree post-TAVI compared to SAVR (21±8 mm Hg vs 35±13 mm Hg, p=0.017). Aortic regurgitation reduced by 8% in both groups, only reaching statistical significance for TAVI (p=0.003). TAVI and SAVR improved (p<0.05) left ventricular (LV) end-systolic volumes (46±18 ml/m2 vs 41±17 ml/m2; 44±22 ml/m2 vs32±6 ml/m2) and mass (83±20 g/m2 vs 65±15 g/m2; 74±11 g/m2 vs 59±8 g/m2). SAVR reduced end-diastolic volumes (92±19 ml/m2 vs 74±12 ml/m2, p<0.001) and TAVI increased EF (52±12% vs 56±10%, p=0.01). MF reduced post-TAVI (10.9±6% vs 8.5±5%, p=0.03) but not post-SAVR (4.2±2% vs 4.1±2%, p=0.98). Myocardial scar (p≤0.01) and baseline ventricular volumes (p<0.001) were the major predictors of reverse remodelling. Conclusions TAVI was comparable to SAVR at LV reverse remodelling and superior at reducing the valvular pressure gradient and MF. Future work should assess the prognostic importance of reverse remodelling and fibrosis post-TAVI to aid patient selection. PMID:23749779

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.

Sex differences in ventricular-vascular coupling following endurance training.

PubMed

Lane, A D; Yan, H; Ranadive, S M; Kappus, R M; Sun, P; Cook, M D; Harvey, I; Woods, J; Wilund, K; Fernhall, B

2014-12-01

Ventricular and vascular coupling is defined as the ratio of arterial elastance (Ea) to ventricular elastance (Elv) and describes the interaction between the heart and arterial system. There are sex differences in both arterial and ventricular function in response to both acute exercise and aerobic exercise training. To examine the effects of aerobic exercise training on elastances and the coupling ratio in young adult men and women. We hypothesized a reduction in the coupling ratio in both sexes due to a decrease in Ea that would be more pronounced in men and an increase in Elv that would be larger in women. Fifty-three healthy, young adults completed the study. Central pulse wave velocity and heart volumes were measured before and after an 8-week aerobic training intervention. Elastances were calculated as Ea = end-systolic pressure/stroke volume and Elv = end-systolic pressure/end-systolic volume and indexed to body surface area. After the intervention, women augmented indexed and un-indexed Elv from 2.09 ± 0.61 to 2.52 ± 0.80 mmHg/ml, p < 0.05, and reduced the coupling ratio from 0.72 ± 18 to 0.62 ± 15, p < 0.05, while men maintained their pre-training ratio (from 0.66 ± 0.20 to 0.74 ± 0.21, p > 0.05). Women also reduced end-systolic pressure (from 91 ± 10 to 87 ± 10 mmHg), and both groups reduced central pulse wave velocity (from 6.0 ± 1.0 to 5.6 ± 0.6 m/s, p < 0.05). We conclude that after 8 weeks of aerobic training, only women reduced their coupling ratio due to an increase in Elv. This suggests that aerobic exercise training elicits sex-dependent changes in the coupling ratio in young, healthy individuals.

Hydrogen sulfide upregulates heme oxygenase-1 expression in rats with volume overload-induced heart failure

PubMed Central

ZHANG, CHAO-YING; LI, XIAO-HUI; ZHANG, TING; FU, JIN; CUI, XIAO-DAI

2013-01-01

The present study investigated the role of hydrogen sulfide (H2S), a novel gaseous transmitter, in chronic heart failure (CHF) induced by left-to-right shunt, leading to volume overload. Thirty male Sprague-Dawley rats were randomly divided into four groups: the shunt group, the sham group, the shunt + sodium hydrosulfide (NaHS) group and the sham + NaHS group. CHF was induced in the rats by abdominal aorta-inferior vena cava shunt operation. Rats in the shunt + NaHS and sham + NaHS groups were injected intraperitoneally with NaHS (H2S donor). Haemodynamic parameters were measured 8 weeks after surgery. In addition, left ventricular heme oxygenase (HO)-1 mRNA expression was measured by real-time PCR. Protein expression of HO-1 was evaluated by western blot analysis. Eight weeks after surgery, compared to the sham group, the left ventricular systolic pressure (LVSP) and left ventricular peak rate of contraction and relaxation (LV±dp/dtmax) were significantly reduced; the left ventricular end-diastolic pressure (LVEDP) was significantly increased in the shunt group (all P<0.05). However, NaHS increased LVSP and LV±dp/dtmax (all P<0.05) and decreased LVEDP (P<0.05). Protein expression of HO-1 was significantly decreased in the shunt group compared to that in the sham group (P<0.05). NaHS increased protein expression of HO-1 compared to that in the shunt group (P<0.05). HO-1 mRNA expression was significantly increased in the shunt + NaHS group compared to that in the shunt group (P<0.01). The present study demonstrated that H2S may play a protective role in volume overload-induced CHF by upregulating protein and mRNA expression of HO-1. PMID:24648967

Pulmonary annulus growth after the modified Blalock-Taussig shunt in tetralogy of Fallot.

PubMed

Nakashima, Kouki; Itatani, Keiichi; Oka, Norihiko; Kitamura, Tadashi; Horai, Tetsuya; Hari, Yosuke; Miyaji, Kagami

2014-09-01

In tetralogy of Fallot (TOF), it is well known that postoperative pulmonary regurgitation reduces right ventricular function during long-term follow-up. Complete repair without a transannular patch should help avoid pulmonary regurgitation. Recently, primary complete repair has been preferred to the staged repair with use of a Blalock-Taussig shunt (BTS) even in neonates or small infants; however, little has been reported about the influence of a BTS on pulmonary annular growth. We examined 40 patients with TOF or double-outlet right ventricle with pulmonary stenosis. Twenty-one patients received a BTS before complete repair, whereas 19 patients underwent primary complete repair. Pulmonary annular size was measured by echocardiography before BTS, complete repair, or both, and ventricular volume was measured by cardiac catheterization. There were no significant differences in complete repair age or body size between the groups. Pulmonary annulus sizes in the BTS group were smaller than those in the primary repair group (Z score, -5.1 ± 2.5 vs -3.7 ± 1.8). After the BTS, significant annular growth (Z score, -2.8 ± 2.1) was observed (p = 0.0028), with a significant increase in left ventricular end-diastolic volume (p = 0.015). When patients with severe pulmonary stenosis (Z score > -7.0) were excluded, pulmonary annular preservation at complete repair was achieved in 64.7% (11/17) of the BTS group and 36.8% (7/19) of the primary repair group (p = 0.088). The BTS increased the pulmonary annular size and the left ventricular volume during the 6 months before complete repair, resulting in preservation of the pulmonary valve function. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Remote Zone Extracellular Volume and Left Ventricular Remodeling in Survivors of ST-Elevation Myocardial Infarction.

PubMed

Carberry, Jaclyn; Carrick, David; Haig, Caroline; Rauhalammi, Samuli M; Ahmed, Nadeem; Mordi, Ify; McEntegart, Margaret; Petrie, Mark C; Eteiba, Hany; Hood, Stuart; Watkins, Stuart; Lindsay, Mitchell; Davie, Andrew; Mahrous, Ahmed; Ford, Ian; Sattar, Naveed; Welsh, Paul; Radjenovic, Aleksandra; Oldroyd, Keith G; Berry, Colin

2016-08-01

The natural history and pathophysiological significance of tissue remodeling in the myocardial remote zone after acute ST-elevation myocardial infarction (STEMI) is incompletely understood. Extracellular volume (ECV) in myocardial regions of interest can now be measured with cardiac magnetic resonance imaging. Patients who sustained an acute STEMI were enrolled in a cohort study (BHF MR-MI [British Heart Foundation Magnetic Resonance Imaging in Acute ST-Segment Elevation Myocardial Infarction study]). Cardiac magnetic resonance was performed at 1.5 Tesla at 2 days and 6 months post STEMI. T1 modified Look-Locker inversion recovery mapping was performed before and 15 minutes after contrast (0.15 mmol/kg gadoterate meglumine) in 140 patients at 2 days post STEMI (mean age: 59 years, 76% male) and in 131 patients at 6 months post STEMI. Remote zone ECV was lower than infarct zone ECV (25.6±2.8% versus 51.4±8.9%; P<0.001). In multivariable regression, left ventricular ejection fraction was inversely associated with remote zone ECV (P<0.001), and diabetes mellitus was positively associated with remote zone ECV (P=0.010). No ST-segment resolution (P=0.034) and extent of ischemic area at risk (P<0.001) were multivariable associates of the change in remote zone ECV at 6 months (ΔECV). ΔECV was a multivariable associate of the change in left ventricular end-diastolic volume at 6 months (regression coefficient [95% confidence interval]: 1.43 (0.10-2.76); P=0.036). ΔECV is implicated in the pathophysiology of left ventricular remodeling post STEMI, but because the effect size is small, ΔECV has limited use as a clinical biomarker of remodeling. URL: https://www.clinicaltrials.gov. Unique identifier: NCT02072850. © 2016 The Authors.

Remote Zone Extracellular Volume and Left Ventricular Remodeling in Survivors of ST-Elevation Myocardial Infarction

PubMed Central

Carberry, Jaclyn; Carrick, David; Haig, Caroline; Rauhalammi, Samuli M.; Ahmed, Nadeem; Mordi, Ify; McEntegart, Margaret; Petrie, Mark C.; Eteiba, Hany; Hood, Stuart; Watkins, Stuart; Lindsay, Mitchell; Davie, Andrew; Mahrous, Ahmed; Ford, Ian; Sattar, Naveed; Welsh, Paul; Radjenovic, Aleksandra; Oldroyd, Keith G.

2016-01-01

The natural history and pathophysiological significance of tissue remodeling in the myocardial remote zone after acute ST-elevation myocardial infarction (STEMI) is incompletely understood. Extracellular volume (ECV) in myocardial regions of interest can now be measured with cardiac magnetic resonance imaging. Patients who sustained an acute STEMI were enrolled in a cohort study (BHF MR-MI [British Heart Foundation Magnetic Resonance Imaging in Acute ST-Segment Elevation Myocardial Infarction study]). Cardiac magnetic resonance was performed at 1.5 Tesla at 2 days and 6 months post STEMI. T1 modified Look-Locker inversion recovery mapping was performed before and 15 minutes after contrast (0.15 mmol/kg gadoterate meglumine) in 140 patients at 2 days post STEMI (mean age: 59 years, 76% male) and in 131 patients at 6 months post STEMI. Remote zone ECV was lower than infarct zone ECV (25.6±2.8% versus 51.4±8.9%; P<0.001). In multivariable regression, left ventricular ejection fraction was inversely associated with remote zone ECV (P<0.001), and diabetes mellitus was positively associated with remote zone ECV (P=0.010). No ST-segment resolution (P=0.034) and extent of ischemic area at risk (P<0.001) were multivariable associates of the change in remote zone ECV at 6 months (ΔECV). ΔECV was a multivariable associate of the change in left ventricular end-diastolic volume at 6 months (regression coefficient [95% confidence interval]: 1.43 (0.10–2.76); P=0.036). ΔECV is implicated in the pathophysiology of left ventricular remodeling post STEMI, but because the effect size is small, ΔECV has limited use as a clinical biomarker of remodeling. Clinical Trial Registration— URL: https://www.clinicaltrials.gov. Unique identifier: NCT02072850. PMID:27354423

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.

Longitudinal relaxographic imaging of white matter hyperintensities in the elderly

PubMed Central

2014-01-01

Background Incidental white matter hyperintensities (WMHs) are common findings on T2-weighted magnetic resonance images of the aged brain and have been associated with cognitive decline. While a variety of pathogenic mechanisms have been proposed, the origin of WMHs and the extent to which lesions in the deep and periventricular white matter reflect distinct etiologies remains unclear. Our aim was to quantify the fractional blood volume (vb) of small WMHs in vivo using a novel magnetic resonance imaging (MRI) approach and examine the contribution of blood–brain barrier disturbances to WMH formation in the deep and periventricular white matter. Methods Twenty-three elderly volunteers (aged 59–82 years) underwent 7 Tesla relaxographic imaging and fluid-attenuated inversion recovery (FLAIR) MRI. Maps of longitudinal relaxation rate constant (R1) were prepared before contrast reagent (CR) injection and throughout CR washout. Voxelwise estimates of vb were determined by fitting temporal changes in R1 values to a two-site model that incorporates the effects of transendothelial water exchange. Average vb values in deep and periventricular WMHs were determined after semi-automated segmentation of FLAIR images. Ventricular permeability was estimated from the change in CSF R1 values during CR washout. Results In the absence of CR, the total water fraction in both deep and periventricular WMHs was increased compared to normal appearing white matter (NAWM). The vb of deep WMHs was 1.8 ± 0.6 mL/100 g and was significantly reduced compared to NAWM (2.4 ± 0.8 mL/100 g). In contrast, the vb of periventricular WMHs was unchanged compared to NAWM, decreased with ventricular volume and showed a positive association with ventricular permeability. Conclusions Hyperintensities in the deep WM appear to be driven by vascular compromise, while those in the periventricular WM are most likely the result of a compromised ependyma in which the small vessels remain relatively intact. These findings support varying contributions of blood–brain barrier and brain-CSF interface disturbances in the pathophysiology of deep and periventricular WMHs in the aged human brain. PMID:25379172

Evaluation of the acute and chronic safety of the biosense injection catheter system in porcine hearts.

PubMed

Kornowski, R; Fuchs, S; Tio, F O; Pierre, A; Epstein, S E; Leon, M B

1999-12-01

Direct myocardial injection of therapeutic agents has been explored as a new method for myocardial revascularization. The integration of a 3D electromechanical mapping catheter with a retractable injection needle should allow for intramyocardial injection to identified sites, obviating the need for open heart surgery. This study assessed the procedural safety and performance characteristics of a novel guided catheter-based transendocardial injection system. The electromagnetic guidance system was coupled with a retrievable 27G needle for left ventricular endocardial injection. Using this system, we injected, transendocardially, methylene-blue (MB) dye tracer at a volume of 0.1 or 0.2 ml per injection in eight normal pigs. Animals were sacrificed acutely, at 1, 3, and 7 days (two animal in each time). Three animals served as controls. The injections were followed by coronary angiography and echocardiogram to assess possible ventricular or coronary perforation and wall motion abnormalities. CK-MB levels were measured up to 24 hr following the procedure. The animals were sacrificed at the assigned time for gross and histopathology evaluation. A total of 101 injections were made in all regions of the heart except the apex and the mitral valve. No animal died as a result of the mapping or injection procedures. Vital signs did not change relative to baseline after the mapping and injection procedures. CK-MB values did not increase over time and there was no evidence of sustained arrhythmia or hemodynamic compromise. There was no evidence of left ventricular or coronary perforation, global or regional wall motion abnormalities, or hemopericardium. On histologic evaluation, the estimated volume of tissue staining was greater than the volume of the injected MB dye due to dispersion of the injectate in the interstitial and intracellular fluid compartments. It is concluded that using this magnetic guidance catheter-based navigational system, it is feasible and safe to perform the transendocardial injection procedure. Thus, if it is determined that direct intramyocardial injection of drugs is a valid therapeutic strategy, this approach offers a clear advantage over surgically based transepicardial injection procedures. Cathet. Cardiovasc. Intervent. 48:447-453, 1999. Copyright 1999 Wiley-Liss, Inc.

Effects on infarct size and left ventricular function of early intravenous injection of anistreplase in acute myocardial infarction. The APSIM Study Investigators.

PubMed

Bassand, J P; Bernard, Y; Lusson, J R; Machecourt, J; Cassagnes, J; Borel, E

1990-03-01

A total of 231 patients suffering from a first acute myocardial infarction were randomly allocated within 4 hours following the onset of symptoms either to anistreplase or anisoylated plasminogen streptokinase activator complex (APSAC), 30 U over 5 minutes, or to conventional heparin therapy, 5000 IU in bolus injection. Heparin was reintroduced in both groups 4 h after initial therapy at a dosage of 500 IU/kg per day. A total of 112 patients received anistreplase and 119 received heparin within a mean period of 188 +/- 62 min following the onset of symptoms. Infarct size was estimated from single photon emission computerized tomography and expressed in percentage of the total myocardial volume. The patency rate of the infarct-related artery was 77% in the anistreplase group and 36% in the heparin group (p less than 0.001). Left ventricular ejection fraction determined from contrast angiography was significantly higher in the anistreplase group than in the heparin group (6 absolute percentage point difference). A significant 31% reduction in infarct size was found in the anistreplase group (33% for the anterior wall infarction subgroup [p less than 0.05] and 16% for the inferior wall infarction subgroup, NS). A close inverse relation was found between the values of left ventricular ejection fraction and infarct size (r = -.73, p less than 0.01). In conclusion, early infusion of anistreplase in acute myocardial infarction produced a high early patency rate, a significant limitation of infarct size, and a significant preservation of left ventricular systolic function, mainly in the anterior wall infarctions.

Right ventricular performance and mass by use of cine MRI late after atrial repair of transposition of the great arteries.

PubMed

Lorenz, C H; Walker, E S; Graham, T P; Powers, T A

1995-11-01

The long-term adaptation of the right ventricle after atrial repair of transposition of the great arteries (TGA) remains a subject of major concern. Cine magnetic resonance imaging (MRI), with its tomographic capabilities, allows unique quantitative evaluation of both right and left ventricular function and mass. Our purpose was to use MRI and an age-matched normal population to examine the typical late adaptation of the right and left ventricles after atrial repair of TGA. Cine MRI was used to study ventricular function and mass in 22 patients after atrial repair of TGA. Images were obtained in short-axis sections from base to apex to derive normalized right and left ventricular mass (RVM and LVM, g/m2), interventricular septal mass (IVSM, g/m2), RV and LV end-diastolic volumes (EDV, mL/m2), and ejection fractions (EF). Results 8 to 23 years after repair were compared with analysis of 24 age- and sex-matched normal volunteers and revealed markedly elevated RVM, decreased LVM and IVSM, normal RV size, and only mildly depressed RVEF. Only 1 of 22 patients had clinical RV dysfunction, and this patient had increased RVM. Cine MRI allows quantitative evaluation of both RV and LV mass and function late after atrial repair of TGA. Longitudinal studies that include these measurements should prove useful in determining the mechanism of late RV failure in these patients. On the basis of these early data, inadequate hypertrophy does not appear to be the cause of late dysfunction in this patient group.

Effects of aldosterone blockade on left ventricular function and clinical status during acute myocardial infarction.

PubMed

Uzunhasan, Isil; Yildiz, Ahmet; Coskun, Ugur; Kalyoncuoglu, Muhsin; Baskurt, Murat; Cakar, Mehmet Akif; Kaya, Aysem; Pehlivanoglu, Seckin; Enar, Rasim; Okcun, Baris

2009-01-01

Heart failure is frequently a serious complication of acute myocardial infarction (AMI). ACE inhibitors, Angiotensin II receptor blockers, beta-blockers and aldosterone receptor blockers have been shown to improve outcomes in this setting. This study aimed to determine the effect of spironolactone on the frequency of clinical heart failure, mortality, rehospitalization and left ventricular functions determined by echocardiography. A total of 82 patients with STEMI hospitalized within 6-12 h of debut of symptoms were included in the study. The patients were randomly assigned into spironolactone (group A) or placebo (group B) groups after informed consent had been obtained. All patients were followed for 6 months. There were no statistically significant differences between the two groups when demographic criteria were compared. The incidence of post-MI angina pectoris, rhythm and conduction disturbance during hospitalization was significantly higher in Group B than in Group A. Although not statistically significant, the incidence of clinical heart failure was slightly lower in Group A than in Group B (5% versus 11%). Left ventricular end-diastolic volumes were slightly lower in Group A than in Group B, although statistically this was not significant. In concordance with these findings, the ejection fraction was slightly higher in Group A than in Group B, although this was not statistically significant (47% versus 44%). This trend continued during a 6-month follow-up after randomization. Our findings suggest that early administration of aldosterone blockers provides additional benefits after AMI, reducing the incidence of post-MI angina pectoris and rhythm and conduction disturbances.

Three-Dimensional Echocardiographic Assessment of Left Heart Chamber Size and Function with Fully Automated Quantification Software in Patients with Atrial Fibrillation.

PubMed

Otani, Kyoko; Nakazono, Akemi; Salgo, Ivan S; Lang, Roberto M; Takeuchi, Masaaki

2016-10-01

Echocardiographic determination of left heart chamber volumetric parameters by using manual tracings during multiple beats is tedious in atrial fibrillation (AF). The aim of this study was to determine the usefulness of fully automated left chamber quantification software with single-beat three-dimensional transthoracic echocardiographic data sets in patients with AF. Single-beat full-volume three-dimensional transthoracic echocardiographic data sets were prospectively acquired during consecutive multiple cardiac beats (≥10 beats) in 88 patients with AF. In protocol 1, left ventricular volumes, left ventricular ejection fraction, and maximal left atrial volume were validated using automated quantification against the manual tracing method in identical beats in 10 patients. In protocol 2, automated quantification-derived averaged values from multiple beats were compared with the corresponding values obtained from the indexed beat in all patients. Excellent correlations of left chamber parameters between automated quantification and the manual method were observed (r = 0.88-0.98) in protocol 1. The time required for the analysis with the automated quantification method (5 min) was significantly less compared with the manual method (27 min) (P < .0001). In protocol 2, there were excellent linear correlations between the averaged left chamber parameters and the corresponding values obtained from the indexed beat (r = 0.94-0.99), and test-retest variability of left chamber parameters was low (3.5%-4.8%). Three-dimensional transthoracic echocardiography with fully automated quantification software is a rapid and reliable way to measure averaged values of left heart chamber parameters during multiple consecutive beats. Thus, it is a potential new approach for left chamber quantification in patients with AF in daily routine practice. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Interstitial Features at Chest CT Enhance the Deleterious Effects of Emphysema in the COPDGene Cohort.

PubMed

Ash, Samuel Y; Harmouche, Rola; Ross, James C; Diaz, Alejandro A; Rahaghi, Farbod N; Sanchez-Ferrero, Gonzalo Vegas; Putman, Rachel K; Hunninghake, Gary M; Onieva, Jorge Onieva; Martinez, Fernando J; Choi, Augustine M; Bowler, Russell P; Lynch, David A; Hatabu, Hiroto; Bhatt, Surya P; Dransfield, Mark T; Wells, J Michael; Rosas, Ivan O; San Jose Estepar, Raul; Washko, George R

2018-06-05

Purpose To determine if interstitial features at chest CT enhance the effect of emphysema on clinical disease severity in smokers without clinical pulmonary fibrosis. Materials and Methods In this retrospective cohort study, an objective CT analysis tool was used to measure interstitial features (reticular changes, honeycombing, centrilobular nodules, linear scar, nodular changes, subpleural lines, and ground-glass opacities) and emphysema in 8266 participants in a study of chronic obstructive pulmonary disease (COPD) called COPDGene (recruited between October 2006 and January 2011). Additive differences in patients with emphysema with interstitial features and in those without interstitial features were analyzed by using t tests, multivariable linear regression, and Kaplan-Meier analysis. Multivariable linear and Cox regression were used to determine if interstitial features modified the effect of continuously measured emphysema on clinical measures of disease severity and mortality. Results Compared with individuals with emphysema alone, those with emphysema and interstitial features had a higher percentage predicted forced expiratory volume in 1 second (absolute difference, 6.4%; P < .001), a lower percentage predicted diffusing capacity of lung for carbon monoxide (DLCO) (absolute difference, 7.4%; P = .034), a 0.019 higher right ventricular-to-left ventricular (RVLV) volume ratio (P = .029), a 43.2-m shorter 6-minute walk distance (6MWD) (P < .001), a 5.9-point higher St George's Respiratory Questionnaire (SGRQ) score (P < .001), and 82% higher mortality (P < .001). In addition, interstitial features modified the effect of emphysema on percentage predicted DLCO, RVLV volume ratio, 6WMD, SGRQ score, and mortality (P for interaction < .05 for all). Conclusion In smokers, the combined presence of interstitial features and emphysema was associated with worse clinical disease severity and higher mortality than was emphysema alone. In addition, interstitial features enhanced the deleterious effects of emphysema on clinical disease severity and mortality. © RSNA, 2018 Online supplemental material is available for this article.

Hyperthyroidism as a reversible cause of right ventricular overload and congestive heart failure

PubMed Central

Di Giovambattista, Raniero

2008-01-01

We describe a case of severe congestive heart failure and right ventricular overload associated with overt hyperthyroidism, completely reversed with antithyroid therapy in a few week. It represents a very unusual presentation of overt hyperthyroidism because of the severity of right heart failure. The impressive right ventricular volume overload made mandatory to perform transesophageal echo and angio-TC examination to exclude the coexistence of ASD or anomalous pulmonary venous return. Only a few cases of reversible right heart failure, with or without pulmonary hypertension, have been reported worldwide. In our case the most striking feature has been the normalization of the cardiovascular findings after six weeks of tiamazole therapy. PMID:18549503

Estimation of left ventricular mass in conscious dogs

NASA Technical Reports Server (NTRS)

Coleman, Bernell; Cothran, Laval N.; Ison-Franklin, E. L.; Hawthorne, E. W.

1986-01-01

A method for the assessment of the development or the regression of left ventricular hypertrophy (LVH) in a conscious instrumented animal is described. First, the single-slice short-axis area-length method for estimating the left-ventricular mass (LVM) and volume (LVV) was validated in 24 formaldehyde-fixed canine hearts, and a regression equation was developed that could be used in the intact animal to correct the sonomicrometrically estimated LVM. The LVM-assessment method, which uses the combined techniques of echocardiography and sonomicrometry (in conjunction with the regression equation), was shown to provide reliable and reproducible day-to-day estimates of LVM and LVV, and to be sensitive enough to detect serial changes during the development of LVH.

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.

NT-pro-BNP levels in patients with acute pulmonary embolism are correlated to right but not left ventricular volume and function.

PubMed

Pasha, Sharif M; Klok, Frederikus A; van der Bijl, Noortje; de Roos, Albert; Kroft, Lucia J M; Huisman, Menno V

2012-08-01

N-terminal pro-Brain Natriuretic Peptide (NT-pro-BNP) is primarily secreted by left ventricular (LV) stretch and wall tension. Notably, NT-pro-BNP is a prognostic marker in acute pulmonary embolism (PE), which primarily stresses the right ventricle (RV). We sought to evaluate the relative contribution of the RV to NT-pro-BNP levels during PE. A post-hoc analysis of an observational prospective outcome study in 113 consecutive patients with computed tomography (CT)-proven PE and 226 patients in whom PE was clinically suspected but ruled out by CT. In all patients RV and LV function was established by assessing ECG-triggered-CT measured ventricular end-diastolic-volumes and ejection fraction (EF). NT-pro-BNP was assessed in all patients. The correlation between RV and LV end-diastolic-volumes and systolic function was evaluated by multiple linear regression corrected for known confounders. In the PE cohort increased RVEF (β-coefficient (95% confidence interval [CI]) -0.044 (± -0.011); p<0.001) and higher RV end-diastolic-volume (β-coefficient 0.005 (± 0.001); p<0.001) were significantly correlated to NT-pro-BNP, while no correlation was found with LVEF (β-coefficient 0.005 (± 0.010); p=0.587) and LV end-diastolic-volume (β-coefficient -0.003 (± 0.002); p=0.074). In control patients without PE we found a strong correlation between NT-pro-BNP levels and LVEF (β-coefficient -0.027 (± -0.006); p<0.001) although not LV end-diastolic-volume (β-coefficient 0.001 (± 0.001); p=0.418). RVEF (β-coefficient -0.002 (± -0.006); p=0.802) and RV end-diastolic-volume (β-coefficient <0.001 (± 0.001); p=0.730) were not correlated in patients without PE. In PE patients, lower RVEF and higher RV end-diastolic-volume were significantly correlated to NT-pro-BNP levels as compared to control patients without PE. These observations provide pathophysiological ground for the well-known prognostic value of NT-pro-BNP in acute PE.

Haemodynamic and energetic properties of stunned myocardium in rabbit hearts.

PubMed Central

Schipke, J. D.; Korbmacher, B.; Dorszewski, A.; Selcan, G.; Sunderdiek, U.; Arnold, G.

1996-01-01

OBJECTIVE--To amplify the description of myocardial stunning. DESIGN--Control versus 30 min after a 20 min no flow ischaemia. EXPERIMENTAL ANIMALS--15 isolated rabbit hearts perfused with erythrocyte suspension. MAIN OUTCOME MEASURES--Left ventricular systolic function in terms of aortic flow, peak systolic pressure (LVPmax), dP/dtmax, and the end systolic pressure-volume relation (ESPVR); early relaxation from dP/dtmin and rate of left ventricular pressure decay (tau). Passive properties: ventricular and myocardial stiffness. Coronary resistance from coronary blood flow and perfusion pressure. Total myocardial oxygen consumption (MVo2tot). Total mechanical energy via pressure-volume area (PVA). Contractile efficiency (Econ) and MVo2 of the unloaded contracting heart (MVo2unl). External mechanical efficiency (Eext) from stroke work and MVo2tot. RESULTS--Systolic variables in stunned myocardium were significantly decreased (mean (SD)): aortic flow: 38 (13) v 9 (11) ml/min; LVPmax: 112 (19) v 74 (18) mm Hg; dP/dtmax: 1475 (400) v 1075 (275) mm Hg/s. ESPVR was not significantly decreased, at 138 (73) v 125 (58) mm Hg/ml, but the volume axis intercept was shifted rightward: 0.30 (0.37) v 0.65 (0.25) ml. Likewise, early relaxation was impaired: dP/dtmin (-1275 (250) v -975 (250) mm Hg/s) and tau (37 (7) v 46 (10) ms). LVPed was significantly decreased at 19 (12) v 12 (7) mm Hg, and both the ventricular (end diastolic pressure-volume relation) and the myocardial stiffness (constant k) were increased by 75% and 31%, respectively. Coronary resistance increased non-significantly from 0.83 (0.31) to 1.04 (0.41) mm Hg/(ml/min/100 g). Decreases in PVA (570 (280) v 270 (200) mm Hg.ml/100 g), MVo2tot (40 (9) v 34 (8) microliters/beat/100 g), and MVo2unl (26 (9) v 22 (6) microliters/beat/100 g) did not reach significance, in contrast to significant decreases in Econ (31 (18) v 14 (7)%) and Eext (0.75 (0.29) v 0.18 (0.25) arbitrary units). CONCLUSIONS--Ventricular systolic function is decreased after brief episodes of ischaemia. The decrease in diastolic function probably amplifies the systolic deterioration during myocardial stunning. Passive diastolic properties are also changed, shown by increases in both ventricular and myocardial stiffness. The increase in coronary resistance indicates stunning at the vascular level which could limit oxygen supply. With maintained MVo2tot during stunning, external efficiency is decreased. Possible candidates for this metabolic stunning are inadequate excitation-contraction coupling and disturbed O2 utilisation by the contractile apparatus. Images PMID:8624873

A comparison of heart function and arrhythmia in clinically asymptomatic patients with beta thalassemia intermedia and beta thalassemia major.

PubMed

Amoozgar, Hamid; Zeighami, Samaneh; Haghpanah, Sezaneh; Karimi, Mehran

2017-01-01

The goal of this study was to compare heart function and arrhythmia in clinically asymptomatic patients with beta thalassemia intermedia and beta thalassemia major. In this cross-sectional study, 60 patients with beta thalassemia major and 60 patients with beta thalassemia intermedia who had clinically no symptoms of arrhythmia and clinically normal heart function were evaluated using 24-hour ambulatory electrocardiogram monitoring and echocardiography. For data analysis SPSS ver.20 software was used. A P-value of less than 0.05 was considered statistically significant. The mean age of the beta thalassemia intermedia patients was 24.18 ± 7.9 years and the mean age in beta thalassemia major was 24.38 ± 7.7 years (P>0.05). Premature atrial contractions (PACs) were observed in 14 (23.3%) patients with beta thalassemia intermedia and in 22 (36.6%) beta thalassemia major patients. Premature ventricular contractions (PVCs) were detected in 8 (13.3%) patients in the beta thalassemia intermediate group and 16 (26.6) patients in the beta thalassemia major group, respectively. The left ventricular diastolic dimension, end-diastolic volume, and stroke volume were significantly higher in beta thalassemia intermedia group (P<0.05). Pulmonary acceleration time as an indicator of pulmonary pressure was lower in beta thalassemia intermedia group. Both atrial and ventricular arrhythmias were more common in the beta thalassemia major group. Higher end-diastolic volume and stroke volume were detected in the beta thalassemia intermedia group. Pulmonary acceleration time was lower in the beta thalassemia intermedia group, which can be an indicator of higher pulmonary pressure.

Right ventricular sex differences in patients with idiopathic pulmonary arterial hypertension characterised by magnetic resonance imaging: pair-matched case controlled study.

PubMed

Swift, Andrew J; Capener, Dave; Hammerton, Charlotte; Thomas, Steven M; Elliot, Charlie; Condliffe, Robin; Wild, Jim M; Kiely, David G

2015-01-01

Sex differences exist in both the prevalence and survival of patients with idiopathic pulmonary arterial hypertension (IPAH). Men are less frequently affected by the condition but have worse outcome as compared to females. We sought to characterise the sex related differences in right ventricular remodelling in age matched male and female patients with IPAH using cardiac magnetic resonance imaging (MRI). A case controlled pair-matched study was conducted with patients matched by age and sex. Steady state free precession (SSFP) MRI of the heart was performed at 1.5T. Cardiac volume, function and mass measurements were corrected for age, sex and BSA according to reference data. 40 age and sex matched patients with IPAH were identified. The mean age was 57 (SD 17) in both male and female cohorts. Men had proportionally lower right ventricular (RV) ejection fraction, RV stroke volume and LV stroke volume than females, p=0.028, p=0.007 and p=0.013, respectively. However, there was no significant difference in RV mass or haemodynamic indices of mPAP and PVR between males and females. Male patients with IPAH have proportionally worse RV function despite similar afterload. We hypothesise that adaptive remodelling of the RV in response to increased afterload in IPAH is more effective in females.

Right Ventricular Sex Differences in Patients with Idiopathic Pulmonary Arterial Hypertension Characterised by Magnetic Resonance Imaging: Pair-Matched Case Controlled Study

PubMed Central

Swift, Andrew J.; Capener, Dave; Hammerton, Charlotte; Thomas, Steven M.; Elliot, Charlie; Condliffe, Robin; Wild, Jim M.; Kiely, David G.

2015-01-01

Purpose Sex differences exist in both the prevalence and survival of patients with idiopathic pulmonary arterial hypertension (IPAH). Men are less frequently affected by the condition but have worse outcome as compared to females. We sought to characterise the sex related differences in right ventricular remodelling in age matched male and female patients with IPAH using cardiac magnetic resonance imaging (MRI). Methods A case controlled pair-matched study was conducted with patients matched by age and sex. Steady state free precession (SSFP) MRI of the heart was performed at 1.5T. Cardiac volume, function and mass measurements were corrected for age, sex and BSA according to reference data. Results 40 age and sex matched patients with IPAH were identified. The mean age was 57 (SD 17) in both male and female cohorts. Men had proportionally lower right ventricular (RV) ejection fraction, RV stroke volume and LV stroke volume than females, p=0.028, p=0.007 and p=0.013, respectively. However, there was no significant difference in RV mass or haemodynamic indices of mPAP and PVR between males and females. Conclusion Male patients with IPAH have proportionally worse RV function despite similar afterload. We hypothesise that adaptive remodelling of the RV in response to increased afterload in IPAH is more effective in females. PMID:25996939

Cognitive correlates of white matter lesion load and brain atrophy

PubMed Central

Dong, Chuanhui; Nabizadeh, Nooshin; Caunca, Michelle; Cheung, Ying Kuen; Rundek, Tatjana; Elkind, Mitchell S.V.; DeCarli, Charles; Sacco, Ralph L.; Stern, Yaakov

2015-01-01

Objective: We investigated white matter lesion load and global and regional brain volumes in relation to domain-specific cognitive performance in the stroke-free Northern Manhattan Study (NOMAS) population. Methods: We quantified white matter hyperintensity volume (WMHV), total cerebral volume (TCV), and total lateral ventricular (TLV) volume, as well as hippocampal and cortical gray matter (GM) lobar volumes in a subgroup. We used general linear models to examine MRI markers in relation to domain-specific cognitive performance, adjusting for key covariates. Results: MRI and cognitive data were available for 1,163 participants (mean age 70 ± 9 years; 60% women; 66% Hispanic, 17% black, 15% white). Across the entire sample, those with greater WMHV had worse processing speed. Those with larger TLV volume did worse on episodic memory, processing speed, and semantic memory tasks, and TCV did not explain domain-specific variability in cognitive performance independent of other measures. Age was an effect modifier, and stratified analysis showed that TCV and WMHV explained variability in some domains above age 70. Smaller hippocampal volume was associated with worse performance across domains, even after adjusting for APOE ε4 and vascular risk factors, whereas smaller frontal lobe volumes were only associated with worse executive function. Conclusions: In this racially/ethnically diverse, community-based sample, white matter lesion load was inversely associated with cognitive performance, independent of brain atrophy. Lateral ventricular, hippocampal, and lobar GM volumes explained domain-specific variability in cognitive performance. PMID:26156514

Positive inotropic and vasodilator actions of milrinone in patients with severe congestive heart failure. Dose-response relationships and comparison to nitroprusside.

PubMed Central

Jaski, B E; Fifer, M A; Wright, R F; Braunwald, E; Colucci, W S

1985-01-01

Milrinone is a potent positive inotropic and vascular smooth muscle-relaxing agent in vitro, and therefore, it is not known to what extent each of these actions contributes to the drug's hemodynamic effects in patients with heart failure. In 11 patients with New York Heart Association class III or IV congestive heart failure, incremental intravenous doses of milrinone were administered to determine the dose-response relationships for heart rate, systemic vascular resistance, and inotropic state, the latter measured by peak positive left ventricular derivative of pressure with respect to time (dP/dt). To clarify further the role of a positive inotropic action, the relative effects of milrinone and nitroprusside on left ventricular stroke work and dP/dt were compared in each patient at doses matched to cause equivalent reductions in mean arterial pressure or systemic vascular resistance, indices of left ventricular afterload. Milrinone caused heart rate, stroke volume, and dP/dt to increase, and systemic vascular resistance to decrease in a concentration-related manner. At the two lowest milrinone doses resulting in serum concentrations of 63 +/- 4 and 156 +/- 5 ng/ml, respectively, milrinone caused significant increases in stroke volume and dP/dt, but no changes in systemic vascular resistance or heart rate. At the maximum milrinone dose administered (mean serum concentration, 427 +/- 11 ng/ml), heart rate increased from 92 +/- 4 to 99 +/- 4 bpm (P less than 0.01), mean aortic pressure fell from 82 +/- 3 to 71 +/- 3 mmHg (P less than 0.01), right atrial pressure fell from 15 +/- 2 to 7 +/- 1 mmHg (P less than 0.005), left ventricular end-diastolic pressure fell from 26 +/- 3 to 18 +/- 3 (P less than 0.005), stroke volume index increased from 20 +/- 2 to 30 +/- 2 ml/m2 (P less than 0.005), stroke work index increased from 14 +/- 2 to 21 +/- 2 g X m/m2 (P less than 0.01), and dP/dt increased from 858 +/- 54 to 1,130 +/- 108 mmHg/s (P less than 0.005). When compared with nitroprusside for a matched reduction in mean aortic pressure or systemic vascular resistance, milrinone caused a significantly greater increase in stroke work index at the same or lower left ventricular end-diastolic pressure. Milrinone caused a concentration-related increase in dP/dt (32% increase at maximum milrinone dose), whereas nitroprusside had no effect. These data in patients with severe heart failure indicate that in addition to a vasodilating effect, milrinone exerts a concentration-related positive inotropic action that contributes significantly to the drug's overall hemodynamic effects. The positive inotropic action occurs at drug levels that do not exert significant chronotropic or vasodilator effects. Images PMID:3973022

Regular endurance training in adolescents impacts atrial and ventricular size and function.

PubMed

Rundqvist, Louise; Engvall, Jan; Faresjö, Maria; Carlsson, Emma; Blomstrand, Peter

2017-06-01

The aims of the study were to explore the effects of long-term endurance exercise on atrial and ventricular size and function in adolescents and to examine whether these changes are related to maximal oxygen uptake (VO2max). Twenty-seven long-term endurance-trained adolescents aged 13-19 years were individually matched by age and gender with 27 controls. All participants, 22 girls and 32 boys, underwent an echocardiographic examination at rest, including standard and colour tissue Doppler investigation. VO2max was assessed during treadmill exercise. All heart dimensions indexed for body size were larger in the physically active group compared with controls: left ventricular end-diastolic volume 60 vs. 50 mL/m2 (P <0.001), left atrial volume 27 vs. 19 mL/m2 (P < 0.001), and right ventricular (RV) and right atrial area 15 vs. 13 and 9 vs. 7 cm2/m2, respectively (P <0.001 for both). There were strong associations between the size of the cardiac chambers and VO2max. Further, we found improved systolic function in the active group compared with controls: left ventricular ejection fraction 61 vs. 59% (P= 0.036), tricuspid annular plane systolic excursion 12 vs. 10 mm/m2 (P= 0.008), and RV early peak systolic velocity s' 11 vs. 10 cm/s (P = 0.031). Cardiac remodelling to long-term endurance exercise in adolescents is manifested by an increase in atrial as well as ventricular dimensions. The physically active group also demonstrated functional remodelling with an increase in TAPSE and systolic RV wall velocity. These findings have practical implications when assessing cardiac enlargement and function in physically active youngsters. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Bridging the gap: Hybrid cardiac echo in the critically ill.

PubMed

Glaser, Jacob J; Cardarelli, Cassandra; Galvagno, Samuel; Scalea, Thomas M; Murthi, Sarah B

2016-11-01

Point-of-care ultrasound often includes cardiac ultrasound. It is commonly used to evaluate cardiac function in critically ill patients but lacks the specific quantitative anatomic assessment afforded by standard transthoracic echocardiography (TTE). We developed the Focused Rapid Echocardiographic Examination (FREE), a hybrid between a cardiac ultrasound and TTE that places an emphasis on cardiac function rather than anatomy. We hypothesized that data obtained from FREE correlate well with TTE while providing actionable information for clinical decision making. FREE examinations evaluating cardiac function (left ventricular ejection fraction), diastolic dysfunction (including early mitral Doppler flow [E] and early mitral tissue Doppler [E']), right ventricular function, cardiac output, preload (left ventricular internal dimension end diastole), stroke volume, stroke volume variation, inferior vena cava diameter, and inferior vena cava collapse were performed. Patients who underwent both a TTE and FREE on the same day were identified as the cohort, and quantitative measurements were compared. Correlation analyses were performed to assess levels of agreement. A total of 462 FREE examinations were performed, in which 69 patients had both a FREE and TTE. FREE ejection fraction was strongly correlated with TTE (r = 0.89, 95% confidence interval). Left ventricular outflow tract, left ventricular internal dimension end diastole, E, and lateral E' derived from FREE were also strongly correlated with TTE measurements (r = 0.83, r = 0.94, r = 0.77, and r = 0.88, respectively). In 82% of the patients, right ventricular function for FREE was the same as that reported for TTE; pericardial effusion was detected on both examinations in 94% of the cases. No significant valvular anatomy was missed with the FREE examination. Functionally rather than anatomically based hybrid ultrasound examinations, like the FREE, facilitate decision making for critically ill patients. The FREE's functional assessment correlates well with TTE measurements and may be of significant clinical value in critically ill patients, especially when used in remote operating environments where resources are limited. Diagnostic test, level III.

Validity of automated measurement of left ventricular ejection fraction and volume using the Philips EPIQ system.

PubMed

Hovnanians, Ninel; Win, Theresa; Makkiya, Mohammed; Zheng, Qi; Taub, Cynthia

2017-11-01

To assess the efficiency and reproducibility of automated measurements of left ventricular (LV) volumes and LV ejection fraction (LVEF) in comparison to manually traced biplane Simpson's method. This is a single-center prospective study. Apical four- and two-chamber views were acquired in patients in sinus rhythm. Two operators independently measured LV volumes and LVEF using biplane Simpson's method. In addition, the image analysis software a2DQ on the Philips EPIQ system was applied to automatically assess the LV volumes and LVEF. Time spent on each analysis, using both methods, was documented. Concordance of echocardiographic measures was evaluated using intraclass correlation (ICC) and Bland-Altman analysis. Manual tracing and automated measurement of LV volumes and LVEF were performed in 184 patients with a mean age of 67.3 ± 17.3 years and BMI 28.0 ± 6.8 kg/m 2 . ICC and Bland-Altman analysis showed good agreements between manual and automated methods measuring LVEF, end-systolic, and end-diastolic volumes. The average analysis time was significantly less using the automated method than manual tracing (116 vs 217 seconds/patient, P < .0001). Automated measurement using the novel image analysis software a2DQ on the Philips EPIQ system produced accurate, efficient, and reproducible assessment of LV volumes and LVEF compared with manual measurement. © 2017, Wiley Periodicals, Inc.

Improved approach to quantitative cardiac volumetrics using automatic thresholding and manual trimming: a cardiovascular MRI study.

PubMed

Rayarao, Geetha; Biederman, Robert W W; Williams, Ronald B; Yamrozik, June A; Lombardi, Richard; Doyle, Mark

2018-01-01

To establish the clinical validity and accuracy of automatic thresholding and manual trimming (ATMT) by comparing the method with the conventional contouring method for in vivo cardiac volume measurements. CMR was performed on 40 subjects (30 patients and 10 controls) using steady-state free precession cine sequences with slices oriented in the short-axis and acquired contiguously from base to apex. Left ventricular (LV) volumes, end-diastolic volume, end-systolic volume, and stroke volume (SV) were obtained with ATMT and with the conventional contouring method. Additionally, SV was measured independently using CMR phase velocity mapping (PVM) of the aorta for validation. Three methods of calculating SV were compared by applying Bland-Altman analysis. The Bland-Altman standard deviation of variation (SD) and offset bias for LV SV for the three sets of data were: ATMT-PVM (7.65, [Formula: see text]), ATMT-contours (7.85, [Formula: see text]), and contour-PVM (11.01, 4.97), respectively. Equating the observed range to the error contribution of each approach, the error magnitude of ATMT:PVM:contours was in the ratio 1:2.4:2.5. Use of ATMT for measuring ventricular volumes accommodates trabeculae and papillary structures more intuitively than contemporary contouring methods. This results in lower variation when analyzing cardiac structure and function and consequently improved accuracy in assessing chamber volumes.

The effect of postoperative medical treatment on left ventricular mass regression after aortic valve replacement.

PubMed

Helder, Meghana R K; Ugur, Murat; Bavaria, Joseph E; Kshettry, Vibhu R; Groh, Mark A; Petracek, Michael R; Jones, Kent W; Suri, Rakesh M; Schaff, Hartzell V

2015-03-01

The study objective was to analyze factors associated with left ventricular mass regression in patients undergoing aortic valve replacement with a newer bioprosthesis, the Trifecta valve pericardial bioprosthesis (St Jude Medical Inc, St Paul, Minn). A total of 444 patients underwent aortic valve replacement with the Trifecta bioprosthesis from 2007 to 2009 at 6 US institutions. The clinical and echocardiographic data of 200 of these patients who had left ventricular hypertrophy and follow-up studies 1 year postoperatively were reviewed and compared to analyze factors affecting left ventricular mass regression. Mean (standard deviation) age of the 200 study patients was 73 (9) years, 66% were men, and 92% had pure or predominant aortic valve stenosis. Complete left ventricular mass regression was observed in 102 patients (51%) by 1 year postoperatively. In univariate analysis, male sex, implantation of larger valves, larger left ventricular end-diastolic volume, and beta-blocker or calcium-channel blocker treatment at dismissal were significantly associated with complete mass regression. In the multivariate model, odds ratios (95% confidence intervals) indicated that male sex (3.38 [1.39-8.26]) and beta-blocker or calcium-channel blocker treatment at dismissal (3.41 [1.40-8.34]) were associated with increased probability of complete left ventricular mass regression. Patients with higher preoperative systolic blood pressure were less likely to have complete left ventricular mass regression (0.98 [0.97-0.99]). Among patients with left ventricular hypertrophy, postoperative treatment with beta-blockers or calcium-channel blockers may enhance mass regression. This highlights the need for close medical follow-up after operation. Labeled valve size was not predictive of left ventricular mass regression. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Mechanical ventilation and thoracic artificial lung assistance during mechanical circulatory support with PUCA pump: in silico study.

PubMed

De Lazzari, Claudio; Genuini, Igino; Quatember, Bernhard; Fedele, Francesco

2014-02-01

Patients assisted with left ventricular assist device (LVAD) may require prolonged mechanical ventilatory assistance secondary to postoperative respiratory failure. The goal of this work is the study of the interdependent effects LVAD like pulsatile catheter (PUCA) pump and mechanical ventilatory support or thoracic artificial lung (TAL), by the hemodynamic point of view, using a numerical simulator of the human cardiovascular system. In the simulator, different circulatory sections are described using lumped parameter models. Lumped parameter models have been designed to describe the hydrodynamic behavior of both PUCA pump and thoracic artificial lung. Ventricular behavior atrial and septum functions were reproduced using variable elastance model. Starting from simulated pathological conditions we studied the effects produced on some hemodynamic variables by simultaneous PUCA pump, thoracic artificial lung or mechanical ventilation assistance. Thoracic artificial lung was applied in parallel or in hybrid mode. The effects of mechanical ventilation have been simulated by changing mean intrathoracic pressure value from -4 mmHg to +5 mmHg. The hemodynamic variables observed during the simulations, in different assisted conditions, were: left and right ventricular end systolic (diastolic) volume, systolic/diastolic aortic pressure, mean pulmonary arterial pressure, left and right mean atrial pressure, mean systemic venous pressure and the total blood flow. Results show that the application of PUCA (without mechanical ventilatory assistance) increases the total blood flow, reduces the left ventricular end systolic volume and increases the diastolic aortic pressure. Parallel TAL assistance increases the right ventricular end diastolic (systolic) volume reduction both when PUCA is switched "ON" and both when PUCA is switched "OFF". By switching "OFF" the PUCA pump, it seems that parallel thoracic artificial lung assistance produces a greater cardiac output (respect to hybrid TAL assistance). Results concerning PUCA and TAL interaction produced by simulations cannot be compared with "in vivo" results since they are not presented in literature. But results concerning the effects produced by LVAD and mechanical ventilation have a trend consistent with those presented in literature. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Semiautomatic three-dimensional CT ventricular volumetry in patients with congenital heart disease: agreement between two methods with different user interaction.

PubMed

Goo, Hyun Woo; Park, Sang-Hyub

2015-12-01

To assess agreement between two semi-automatic, three-dimensional (3D) computed tomography (CT) ventricular volumetry methods with different user interactions in patients with congenital heart disease. In 30 patients with congenital heart disease (median age 8 years, range 5 days-33 years; 20 men), dual-source, multi-section, electrocardiography-synchronized cardiac CT was obtained at the end-systolic (n = 22) and/or end-diastolic (n = 28) phase. Nineteen left ventricle end-systolic (LV ESV), 28 left ventricle end-diastolic (LV EDV), 22 right ventricle end-systolic (RV ESV), and 28 right ventricle end-diastolic volumes (RV EDV) were successfully calculated using two semi-automatic, 3D segmentation methods with different user interactions (high in method 1, low in method 2). The calculated ventricular volumes of the two methods were compared and correlated. A P value <0.05 was considered statistically significant. LV ESV (35.95 ± 23.49 ml), LV EDV (88.76 ± 61.83 ml), and RV ESV (46.87 ± 47.39 ml) measured by method 2 were slightly but significantly smaller than those measured by method 1 (41.25 ± 26.94 ml, 92.20 ± 62.69 ml, 53.61 ± 50.08 ml for LV ESV, LV EDV, and RV ESV, respectively; P ≤ 0.02). In contrast, no statistically significant difference in RV EDV (122.57 ± 88.57 ml in method 1, 123.83 ± 89.89 ml in method 2; P = 0.36) was found between the two methods. All ventricular volumes showed very high correlation (R = 0.978, 0.993, 0.985, 0.997 for LV ESV, LV EDV, RV ESV, and RV EDV, respectively; P < 0.001) between the two methods. In patients with congenital heart disease, 3D CT ventricular volumetry shows good agreement and high correlation between the two methods, but method 2 tends to slightly underestimate LV ESV, LV EDV, and RV ESV.

Myocardial effective transverse relaxation time T2* Correlates with left ventricular wall thickness: A 7.0 T MRI study.

PubMed

Huelnhagen, Till; Hezel, Fabian; Serradas Duarte, Teresa; Pohlmann, Andreas; Oezerdem, Celal; Flemming, Bert; Seeliger, Erdmann; Prothmann, Marcel; Schulz-Menger, Jeanette; Niendorf, Thoralf

2017-06-01

Myocardial effective relaxation time T2* is commonly regarded as a surrogate for myocardial tissue oxygenation. However, it is legitimate to assume that there are multiple factors that influence T2*. To this end, this study investigates the relationship between T2* and cardiac macromorphology given by left ventricular (LV) wall thickness and left ventricular radius, and provides interpretation of the results in the physiological context. High spatio-temporally resolved myocardial CINE T2* mapping was performed in 10 healthy volunteers using a 7.0 Tesla (T) full-body MRI system. Ventricular septal wall thickness, left ventricular inner radius, and T2* were analyzed. Macroscopic magnetic field changes were elucidated using cardiac phase-resolved magnetic field maps. Ventricular septal T2* changes periodically over the cardiac cycle, increasing in systole and decreasing in diastole. Ventricular septal wall thickness and T2* showed a significant positive correlation, whereas the inner LV radius and T2* were negatively correlated. The effect of macroscopic magnetic field gradients on T2* can be considered minor in the ventricular septum. Our findings suggest that myocardial T2* is related to tissue blood volume fraction. Temporally resolved T2* mapping could be beneficial for myocardial tissue characterization and for understanding cardiac (patho)physiology in vivo. Magn Reson Med 77:2381-2389, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

RIGHT AND LEFT VENTRICULAR DIASTOLIC PRESSURE–VOLUME RELATIONS: A COMPREHENSIVE REVIEW

PubMed Central

Pasipoularides, Ares

2012-01-01

Ventricular compliance alterations can affect cardiac performance and adaptations. Moreover, diastolic mechanics are important in assessing both diastolic and systolic function, since any filling impairment can compromise systolic function. A sigmoidal passive filling pressure-volume relationship, developed using chronically instrumented, awake-animal disease models, is clinically adaptable to evaluating diastolic dynamics using subject-specific micromanometric and volumetric data from the entire filling period of any heartbeat(s). This innovative relationship is the global, integrated expression of chamber geometry, wall thickness, and passive myocardial wall properties. Chamber and myocardial compliance curves of both ventricles can be computed by the sigmoidal methodology over the entire filling period and plotted over appropriate filling pressure ranges. Important characteristics of the compliance curves can be examined and compared between the right and the left ventricle, and for different physiological and pathological conditions. The sigmoidal paradigm is more accurate and, therefore, a better alternative to the conventional exponential pressure-volume approximation. PMID:23179133

Left Atrial Volume Determinants in Patients with Non-Ischemic Dilated Cardiomyopathy

PubMed Central

Mancuso, Frederico José Neves; Moisés, Valdir Ambrósio; Almeida, Dirceu Rodrigues; Poyares, Dalva; Storti, Luciana Julio; Oliveira, Wércules Antonio; Brito, Flavio Souza; de Paola, Angelo Amato Vincenzo; Carvalho, Antonio Carlos Camargo; Campos, Orlando

2015-01-01

Background Left atrial volume (LAV) is a predictor of prognosis in patients with heart failure. Objective We aimed to evaluate the determinants of LAV in patients with dilated cardiomyopathy (DCM). Methods Ninety patients with DCM and left ventricular (LV) ejection fraction ≤ 0.50 were included. LAV was measured with real-time three-dimensional echocardiography (eco3D). The variables evaluated were heart rate, systolic blood pressure, LV end-diastolic volume and end-systolic volume and ejection fraction (eco3D), mitral inflow E wave, tissue Doppler e´ wave, E/e´ ratio, intraventricular dyssynchrony, 3D dyssynchrony index and mitral regurgitation vena contracta. Pearson´s coefficient was used to identify the correlation of the LAV with the assessed variables. A multiple linear regression model was developed that included LAV as the dependent variable and the variables correlated with it as the predictive variables. Results Mean age was 52 ± 11 years-old, LV ejection fraction: 31.5 ± 8.0% (16-50%) and LAV: 39.2±15.7 ml/m2. The variables that correlated with the LAV were LV end-diastolic volume (r = 0.38; p < 0.01), LV end-systolic volume (r = 0.43; p < 0.001), LV ejection fraction (r = -0.36; p < 0.01), E wave (r = 0.50; p < 0.01), E/e´ ratio (r = 0.51; p < 0.01) and mitral regurgitation (r = 0.53; p < 0.01). A multivariate analysis identified the E/e´ ratio (p = 0.02) and mitral regurgitation (p = 0.02) as the only independent variables associated with LAV increase. Conclusion The LAV is independently determined by LV filling pressures (E/e´ ratio) and mitral regurgitation in DCM. PMID:25993483

Left Atrial Volume Determinants in Patients with Non-Ischemic Dilated Cardiomyopathy.

PubMed

Mancuso, Frederico José Neves; Moisés, Valdir Ambrósio; Almeida, Dirceu Rodrigues; Poyares, Dalva; Storti, Luciana Julio; Oliveira, Wércules Antonio; Brito, Flavio Souza; Paola, Angelo Amato Vincenzo de; Carvalho, Antonio Carlos Camargo; Campos, Orlando

2015-07-01

Left atrial volume (LAV) is a predictor of prognosis in patients with heart failure. We aimed to evaluate the determinants of LAV in patients with dilated cardiomyopathy (DCM). Ninety patients with DCM and left ventricular (LV) ejection fraction ≤ 0.50 were included. LAV was measured with real-time three-dimensional echocardiography (eco3D). The variables evaluated were heart rate, systolic blood pressure, LV end-diastolic volume and end-systolic volume and ejection fraction (eco3D), mitral inflow E wave, tissue Doppler e' wave, E/e' ratio, intraventricular dyssynchrony, 3D dyssynchrony index and mitral regurgitation vena contracta. Pearson's coefficient was used to identify the correlation of the LAV with the assessed variables. A multiple linear regression model was developed that included LAV as the dependent variable and the variables correlated with it as the predictive variables. Mean age was 52 ± 11 years-old, LV ejection fraction: 31.5 ± 8.0% (16-50%) and LAV: 39.2±15.7 ml/m2. The variables that correlated with the LAV were LV end-diastolic volume (r = 0.38; p < 0.01), LV end-systolic volume (r = 0.43; p < 0.001), LV ejection fraction (r = -0.36; p < 0.01), E wave (r = 0.50; p < 0.01), E/e' ratio (r = 0.51; p < 0.01) and mitral regurgitation (r = 0.53; p < 0.01). A multivariate analysis identified the E/e' ratio (p = 0.02) and mitral regurgitation (p = 0.02) as the only independent variables associated with LAV increase. The LAV is independently determined by LV filling pressures (E/e' ratio) and mitral regurgitation in DCM.

Hybrid model analysis of intra-aortic balloon pump performance as a function of ventricular and circulatory parameters.

PubMed

Ferrari, Gianfranco; Khir, Ashraf W; Fresiello, Libera; Di Molfetta, Arianna; Kozarski, Maciej

2011-09-01

We investigated the effects of the intra-aortic balloon pump (IABP) on endocardial viability ratio (EVR), cardiac output (CO), end-systolic (V(es)) and end-diastolic (V(ed)) ventricular volumes, total coronary blood flow (TCBF), and ventricular energetics (external work [EW], pressure-volume area [PVA]) under different ventricular (E(max) and diastolic stiffness) and circulatory (arterial compliance) parameters. We derived a hybrid model from a computational model, which is based on merging computational and hydraulic submodels. The lumped parameter computational submodel consists of left and right hearts and systemic, pulmonary, and coronary circulations. The hydraulic submodel includes part of the systemic arterial circulation, essentially a silicone rubber tube representing the aorta, which contains a 40-mL IAB. EVR, CO, V(es), and V(ed), TCBF and ventricular energetics (EW, PVA) were analyzed against the ranges of left ventricular E(max) (0.3-0.5-1 mm Hg/cm(3)) and diastolic stiffness V(stiffness) (≈0.08 and ≈0.3 mm Hg/cm(3), obtained by changing diastolic stiffness constant) and systemic arterial compliance (1.8-2.5 cm(3)/mm Hg). All experiments were performed comparing the selected variables before and during IABP assistance. Increasing E(maxl) from 0.5 to 2 mm Hg/cm(3) resulted in IABP assistance producing lower percentage changes in the selected variables. The changes in ventricular diastolic stiffness strongly influence both absolute value of EVR and its variations during IABP (71 and 65% for lower and higher arterial compliance, respectively). V(ed) and V(es) changes are rather small but higher for lower E(max) and higher V(stiffness). Lower E(max) and higher V(stiffness) resulted in higher TCBF and CO during IABP assistance (∼35 and 10%, respectively). The use of this hybrid model allows for testing real devices in realistic, stable, and repeatable circulatory conditions. Specifically, the presented results show that IABP performance is dependent, at least in part, on left ventricular filling, ejection characteristics, and arterial compliance. It is possible in this way to simulate patient-specific conditions and predict the IABP performance at different values of the circulatory or ventricular parameters. Further work is required to study the conditions for heart recovery modeling, baroreceptor controls, and physiological feedbacks. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Stunning and Right Ventricular Dysfunction Is Induced by Coronary Balloon Occlusion and Rapid Pacing in Humans: Insights From Right Ventricular Conductance Catheter Studies.

PubMed

Axell, Richard G; Giblett, Joel P; White, Paul A; Klein, Andrew; Hampton-Til, James; O'Sullivan, Michael; Braganza, Denise; Davies, William R; West, Nick E J; Densem, Cameron G; Hoole, Stephen P

2017-06-06

We sought to determine whether right ventricular stunning could be detected after supply (during coronary balloon occlusion [BO]) and supply/demand ischemia (induced by rapid pacing [RP] during transcatheter aortic valve replacement) in humans. Ten subjects with single-vessel right coronary artery disease undergoing percutaneous coronary intervention with normal ventricular function were studied in the BO group. Ten subjects undergoing transfemoral transcatheter aortic valve replacement were studied in the RP group. In both, a conductance catheter was placed into the right ventricle, and pressure volume loops were recorded at baseline and for intervals over 15 minutes after a low-pressure BO for 1 minute or a cumulative duration of RP for up to 1 minute. Ischemia-induced diastolic dysfunction was seen 1 minute after RP (end-diastolic pressure [mm Hg]: 8.1±4.2 versus 12.1±4.1, P <0.001) and BO (end-diastolic pressure [mm Hg]: 8.1 ± 4.0 versus 8.7±4.0, P =0.03). Impairment of systolic and diastolic function after BO remained at 15-minutes recovery (ejection fraction [%]: 55.7±9.0 versus 47.8±6.3, P <0.01; end-diastolic pressure [mm Hg]: 8.1±4.0 versus 9.2±3.9, P <0.01). Persistent diastolic dysfunction was also evident in the RP group at 15-minutes recovery (end-diastolic pressure [mm Hg]: 8.1±4.1 versus 9.9±4.4, P =0.03) and there was also sustained impairment of load-independent indices of systolic function at 15 minutes after RP (end-systolic elastance and ventriculo-arterial coupling [mm Hg/mL]: 1.25±0.31 versus 0.85±0.43, P <0.01). RP and right coronary artery balloon occlusion both cause ischemic right ventricular dysfunction with stunning observed later during the procedure. This may have intraoperative implications in patients without right ventricular functional reserve. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

A new methodological approach to assess cardiac work by pressure-volume and stress-length relations in patients with aortic valve stenosis and dilated cardiomyopathy.

PubMed

Alter, P; Rupp, H; Rominger, M B; Klose, K J; Maisch, B

2008-01-01

In experimental animals, cardiac work is derived from pressure-volume area and analyzed further using stress-length relations. Lack of methods for determining accurately myocardial mass has until now prevented the use of stress-length relations in patients. We hypothesized, therefore, that not only pressure-volume loops but also stress-length diagrams can be derived from cardiac volume and cardiac mass as assessed by cardiac magnetic resonance imaging (CMR) and invasively measured pressure. Left ventricular (LV) volume and myocardial mass were assessed in seven patients with aortic valve stenosis (AS), eight with dilated cardiomyopathy (DCM), and eight controls using electrocardiogram (ECG)-gated CMR. LV pressure was measured invasively. Pressure-volume curves were calculated based on ECG triggering. Stroke work was assessed as area within the pressure-volume loop. LV wall stress was calculated using a thick-wall sphere model. Similarly, stress-length loops were calculated to quantify stress-length-based work. Taking the LV geometry into account, the normalization with regard to ventricular circumference resulted in "myocardial work." Patients with AS (valve area 0.73+/-0.18 cm(2)) exhibited an increased LV myocardial mass when compared with controls (P<0.05). LV wall stress was increased in DCM but not in AS. Stroke work of AS was unchanged when compared with controls (0.539+/-0.272 vs 0.621+/-0.138 Nm, not significant), whereas DCM exhibited a significant depression (0.367+/-0.157 Nm, P<0.05). Myocardial work was significantly reduced in both AS and DCM when compared with controls (129.8+/-69.6, 200.6+/-80.1, 332.2+/-89.6 Nm/m(2), P<0.05), also after normalization (7.40+/-5.07, 6.27+/-3.20, 14.6+/-4.07 Nm/m(2), P<0.001). It is feasible to obtain LV pressure-volume and stress-length diagrams in patients based on the present novel methodological approach of using CMR and invasive pressure measurement. Myocardial work was reduced in patients with DCM and noteworthy also in AS, while stroke work was reduced in DCM only. Most likely, deterioration of myocardial work is crucial for the prognosis. It is suggested to include these basic physiological procedures in the clinical assessment of the pump function of the heart.

Right Ventricular Outflow Tract Septal Pacing Is Superior to Right Ventricular Apical Pacing

PubMed Central

Zou, Cao; Song, Jianping; Li, Hui; Huang, Xingmei; Liu, Yuping; Zhao, Caiming; Shi, Xin; Yang, Xiangjun

2015-01-01

Background The effects of right ventricular apical pacing (RVAP) and right ventricular outflow tract (RVOT) septal pacing on atrial and ventricular electrophysiology have not been thoroughly compared. Methods and Results To identify a more favorable pacing strategy with fewer adverse effects, 80 patients who had complete atrioventricular block with normal cardiac function and who were treated with either RVAP (n=42) or RVOT septal pacing (n=38) were recruited after an average of 2 years of follow‐up. The data from electrocardiography and echocardiography performed before pacemaker implantation and at the end of follow‐up were collected. The patients in the RVOT septal pacing and RVAP groups showed similar demographic and clinical characteristics before pacing treatments. After a mean follow‐up of 2 years, the final maximum P‐wave duration; P‐wave dispersion; Q‐, R‐, and S‐wave complex duration; left atrial volume index; left ventricular end‐systolic diameter; ratio of transmitral early diastolic filling velocity to mitral annular early diastolic velocity; and interventricular mechanical delay in the RVOT septal pacing group were significantly less than those in the RVAP group (P<0.05). The final left ventricular ejection fraction of the RVOT septal pacing group was significantly higher than that of the RVAP group (P<0.05). Conclusions Compared with RVAP, RVOT septal pacing has fewer adverse effects regarding atrial electrical activity and structure in patients with normal cardiac function. PMID:25896891

Is hydrotherapy an appropriate form of exercise for elderly patients with biventricular systolic heart failure?

PubMed Central

Sveälv, Bente Grüner; Täng, Margareta Scharin; Cider, Åsa

2012-01-01

Hydrotherapy (exercise in warm water) is considered to be a safe and beneficial method to use in the rehabilitation of stable heart failure patients, but there is little information on the effect of the increased venous return and enhanced preload in elderly patients with biventricular heart failure. We present a case of an elderly man who was recruited to participate in a hydrotherapy study. We compared echocardiographic data during warm water immersion with land measurements, and observed increases in stroke volume from 32 mL (land) to 42 mL (water), left ventricular ejection fraction from 22% to 24%, left ventricular systolic velocity from 4.8 cm/s to 5.0 cm/s and left atrioventricular plane displacement from 2.1 mm to 2.2 mm. By contrast, right ventricular systolic velocity decreased from 11.2 cm/s to 8.4 cm/s and right atrioventricular plane displacement from 8.1 mm to 4.7 mm. The tricuspid pressure gradient rose from 18 mmHg on land to 50 mmHg during warm water immersion. Thus, although left ventricular systolic function was relatively unaffected during warm water immersion, we observed a decrease in right ventricular function with an augmented right ventricular pressure. We recommend further investigations to observe the cardiac effect of warm water immersion on patients with biventricular systolic heart failure and at risk of elevated right ventricular pressure. PMID:23341846

Effects of increased left ventricular wall thickness on the myocardium in severe aortic stenosis with normal left ventricular ejection fraction: Two- and three-dimensional multilayer speckle tracking echocardiography.

PubMed

Cho, Eun Jeong; Park, Sung-Ji; Kim, Eun Kyoung; Lee, Ga Yeon; Chang, Sung-A; Choi, Jin-Oh; Lee, Sang-Chol; Park, Seung Woo

2017-04-01

The aim of this study was to determine the capability of real time three-dimensional echocardiography (RT3DE) and two-dimensional (2D) multilayer speckle tracking echocardiography (MSTE) for evaluation of early myocardial dysfunction triggered by increased left ventricular (LV) wall thickness in severe aortic stenosis (AS) with normal LV ejection fraction (EF≥55%). Conventional, RT3D STE and 2D MSTE were performed in 45 patients (mean 68.9±9.0 years) with severe AS (aortic valve area <1 cm 2 , aortic velocity Vmax >4 m/s or mean PG >40 mm Hg) and normal left ventricular ejection fraction (LVEF) without overt coronary artery disease and in 18 age-, sex-matched healthy controls. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were calculated using RT3DE and MSTE. The severe AS group had lower 3D GLS, GRS, GAS and 2D epicardium, and mid-wall and endocardium GLS compared to healthy controls. In MSTE analysis, 2D LS and CS values decreased from the endocardial layer toward the epicardial layer. Severe AS patients with increased LV wall thickness had lower 3D GLS and 2D epicardium, and mid-wall and endocardium GLS compared with severe AS patients without LV wall thickening. GLS on RT3D STE was correlated with GLS on 2D MSTE, left ventricular mass index, LVEF, left atrial volume index, and lnNT-proBNP. RT3DE and 2D MSTE can be used to identify subtle contractile dysfunction triggered by increased LV wall thickness in severe AS with normal LVEF. Therefore, RT3D STE and 2D MSTE may provide additional information that can facilitate decision-making regarding severe AS patients with increased LV wall thickness and normal LV function. © 2017, Wiley Periodicals, Inc.

Feasibility of single-beat full-volume capture real-time three-dimensional echocardiography for quantification of right ventricular volume: validation by cardiac magnetic resonance imaging.

PubMed

Zhang, Quan Bin; Sun, Jing Ping; Gao, Rui Feng; Lee, Alex Pui-Wai; Feng, Yan Lin; Liu, Xiao Rong; Sheng, Wei; Liu, Feng; Yang, Xing Sheng; Fang, Fang; Yu, Cheuk-Man

2013-10-09

The lack of an accurate noninvasive method for assessing right ventricular (RV) volume and function has been a major deficiency of two-dimensional (2D) echocardiography. The aim of our study was to test the feasibility of single-beat full-volume capture with real-time three-dimensional echo (3DE) imaging system for the evaluation of RV volumes and function validated by cardiac magnetic resonance imaging (CMRI). Sixty-one subjects (16 normal subjects, 20 patients with hypertension, 16 patients with pulmonary heart disease and 9 patients with coronary heart disease) were studied. RV volume and function assessments using 3DE were compared with manual tracing with CMRI as the reference method. Fifty-nine of 61 patients (96.7%; 36 male, mean age, 62 ± 15 years) had adequate three-dimensional echocardiographic data sets for analysis. The mean RV end diastolic volume (EDV) was 105 ± 38 ml, end-systolic volume (ESV) was 60 ± 30 and RV ejection fraction (EF) was 44 ± 11% by CMRI; and EDV 103 ± 38 ml, ESV 60 ± 28 ml and RV EF 41 ± 13% by 3DE. The correlations and agreements between measurements estimated by two methods were acceptable. RV volumes and function can be analyzed with 3DE software in most of subjects with or without heart diseases, which is able to be estimated with single-beat full-volume capture with real-time 3DE compared with CMRI. © 2013.

Nonlinear isochrones in murine left ventricular pressure-volume loops: how well does the time-varying elastance concept hold?

PubMed

Claessens, T E; Georgakopoulos, D; Afanasyeva, M; Vermeersch, S J; Millar, H D; Stergiopulos, N; Westerhof, N; Verdonck, P R; Segers, P

2006-04-01

The linear time-varying elastance theory is frequently used to describe the change in ventricular stiffness during the cardiac cycle. The concept assumes that all isochrones (i.e., curves that connect pressure-volume data occurring at the same time) are linear and have a common volume intercept. Of specific interest is the steepest isochrone, the end-systolic pressure-volume relationship (ESPVR), of which the slope serves as an index for cardiac contractile function. Pressure-volume measurements, achieved with a combined pressure-conductance catheter in the left ventricle of 13 open-chest anesthetized mice, showed a marked curvilinearity of the isochrones. We therefore analyzed the shape of the isochrones by using six regression algorithms (two linear, two quadratic, and two logarithmic, each with a fixed or time-varying intercept) and discussed the consequences for the elastance concept. Our main observations were 1) the volume intercept varies considerably with time; 2) isochrones are equally well described by using quadratic or logarithmic regression; 3) linear regression with a fixed intercept shows poor correlation (R(2) < 0.75) during isovolumic relaxation and early filling; and 4) logarithmic regression is superior in estimating the fixed volume intercept of the ESPVR. In conclusion, the linear time-varying elastance fails to provide a sufficiently robust model to account for changes in pressure and volume during the cardiac cycle in the mouse ventricle. A new framework accounting for the nonlinear shape of the isochrones needs to be developed.

The importance of the cortical subarachnoid space in understanding hydrocephalus.

PubMed

Rekate, Harold L; Nadkarni, Trimurti D; Wallace, Donna

2008-07-01

In this paper the authors define the role of the cortical subarachnoid space (CSAS) in poorly understood forms of hydrocephalus to cerebrospinal fluid (CSF) dynamics to improve understanding of the importance of the CSAS and its role in selecting patients for endoscopic third ventriculostomy (ETV). The secondary purpose of this work was to define testable hypotheses to explain enigmatic disorders of CSF dynamics and to suggest how these concepts could be tested. The magnitude of the contribution of the CSAS is explored using the solid geometry of concentric spheres. With this starting point, clinical conditions in which CSF dynamics are not easily understood are explored regarding the potential role of the CSAS. Overall, problems of CSF dynamics are easily understood. Insights may be gained when the results of a pathological process or its treatment vary from what has been expected. Acute changes in ventricular volume at the time that hydrocephalus develops, the failure of shunts, and the changes in ventricular volume with shunt repair may occur very rapidly. Changes in the volume of water in the brain, especially in the brain substance itself, are unlikely to occur at this rapid rate and may be interpreted as a simple redistribution of the CSF between the ventricle and CSAS with no initial change in the actual volume of brain parenchyma. Problems such as pseudotumor cerebri, shunt failure with nonresponsive ventricles, and negative-pressure hydrocephalus can be explained by assessing the ability of ventricular CSF to flow to the CSAS and the ability of this fluid to exit this compartment. Ventricular enlargement at the time of shunt failure implies a failure of flow between the ventricles and CSAS, implying that all patients who show this phenomenon are potential candidates for ETV. The important role of the CSAS in the pathophysiology of various forms of hydrocephalus has been largely ignored. Attention to the dynamics of the CSF in this compartment will improve understanding of enigmatic conditions of hydrocephalus and improve selection criteria for treatment paradigms such as ETV. These concepts lead to clearly defined problems that may be solved by the creation of a central database to address these issues.

Arterial Ventricular Uncoupling with Age and Disease and Recoupling with Exercise

PubMed Central

Chantler, Paul D

2017-01-01

The deterioration in arterial and cardiac function with aging impairs arterial ventricular coupling, an important determinant of cardiovascular performance. However, exercise training improves arterial ventricular coupling especially during exercise during the age and disease process. This review examines the concept of arterial-ventricular coupling, and how age, and disease uncouples but exercise training recouples the heart and arterial system. PMID:28072585

Protective effects of acute exercise prior to doxorubicin on cardiac function of breast cancer patients: A proof-of-concept RCT.

PubMed

Kirkham, A A; Shave, R E; Bland, K A; Bovard, J M; Eves, N D; Gelmon, K A; McKenzie, D C; Virani, S A; Stöhr, E J; Warburton, D E R; Campbell, K L

2017-10-15

Preclinical studies have reported that a single treadmill session performed 24h prior to doxorubicin provides cardio-protection. We aimed to characterize the acute change in cardiac function following an initial doxorubicin treatment in humans and determine whether an exercise session performed 24h prior to treatment changes this response. Breast cancer patients were randomized to either 30min of vigorous-intensity exercise 24h prior to the first doxorubicin treatment (n=13), or no vigorous exercise for 72h prior to treatment (control, n=11). Echocardiographically-derived left ventricular volumes, longitudinal strain, twist, E/A ratio, and circulating NT-proBNP, a marker of later cardiotoxicity, were measured before and 24-48h after the treatment. Following treatment in the control group, NT-proBNP, end-diastolic and stroke volumes, cardiac output, E/A ratio, strain, diastolic strain rate, twist, and untwist velocity significantly increased (all p≤0.01). Whereas systemic vascular resistance (p<0.01) decreased, and ejection fraction (p=0.02) and systolic strain rate (p<0.01) increased in the exercise group only. Relative to control, the exercise group had a significantly lower NT-proBNP (p<0.01) and a 46% risk reduction of exceeding the cut-point used to exclude acute heart failure. The first doxorubicin treatment is associated with acutely increased NT-proBNP, echocardiographic parameters of myocardial relaxation, left ventricular volume overload, and changes in longitudinal strain and twist opposite in direction to documented longer-term changes. An exercise session performed 24h prior to treatment attenuated NT-proBNP release and increased systolic function. Future investigations should verify these findings in a larger cohort and across multiple courses of doxorubicin. Copyright © 2017 Elsevier B.V. All rights reserved.

MR elastography of hydrocephalus

NASA Astrophysics Data System (ADS)

Pattison, Adam J.; Lollis, S. Scott; Perrinez, Phillip R.; Weaver, John B.; Paulsen, Keith D.

2009-02-01

Hydrocephalus occurs due to a blockage in the transmission of cerebrospinal fluid (CSF) in either the ventricles or subarachnoid space. Characteristics of this condition include increased intracranial pressure, which can result in neurologic deterioration [1]. Magnetic resonance elastography (MRE) is an imaging technique that estimates the mechanical properties of tissue in vivo. While some investigations of brain tissue have been performed using MRE [2,3,4,5], the effects due to changes in interstitial pressure and fluid content on the mechanical properties of the brain remain unknown. The purpose of this work is to assess the potential of MRE to differentiate between the reconstructed properties of normal and hydrocephalic brains. MRE data was acquired in 18 female feline subjects, 12 of which received kaolin injections resulting in an acute form of hydrocephalus. In each animal, four MRE scans were performed during the process including one pre-injection and three post-injection scans. The elastic parameters were obtained using a subzone-based reconstruction algorithm that solves Navier's equations for linearly elastic materials [6]. The remaining cats were used as controls, injected with saline instead of kaolin. To determine the state of hydrocephalus, ventricular volume was estimated from segmenting anatomical images. The mean ventricular volume of hydrocephalic cats significantly increased (P <~ 0.0001) between the first and second scans. The mean volume was not observed to increase (P >~ 0.5) for the control cats. Also, there was an observable increase in the recorded elastic shear modulus of brain tissue in the normal and hydrocephalic acquisitions. Results suggest that MRE is able to detect changes in the mechanical properties of brain tissue resulting from kaolin-induced hydrocephalus, indicating the need for further study.

Evaluation of left ventricular function using electrocardiographically gated myocardial SPECT with (123)I-labeled fatty acid analog.

PubMed

Nanasato, M; Ando, A; Isobe, S; Nonokawa, M; Hirayama, H; Tsuboi, N; Ito, T; Hirai, M; Yokota, M; Saito, H

2001-12-01

Electrocardiographically (ECG) gated myocardial SPECT with (99m)Tc-tetrofosmin has been used widely to assess left ventricular (LV) function. However, the accuracy of variables using ECG gated myocardial SPECT with beta-methyl-p-(123)I-iodophenylpentadecanoic acid (BMIPP) has not been well defined. Thirty-six patients (29 men, 7 women; mean age, 61.6 +/- 15.6 y) with ischemic heart disease underwent ECG gated myocardial SPECT with (123)I-BMIPP and with (99m)Tc-tetrofosmin and left ventriculography (LVG) within 1 wk. LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), and LV end-systolic volume (LVESV) were determined on gated SPECT using commercially available software for automatic data analysis. These volume-related items on LVG were calculated with an area-length method and were estimated by 2 independent observers to evaluate interobserver validity. The regional wall motion with these methods was assessed visually. LVEF was 41.1% +/- 12.5% on gated SPECT with (123)I-BMIPP, 44.5% +/- 13.1% on gated SPECT with (99m)Tc-tetrofosmin, and 46.0% +/- 12.7% on LVG. Global LV function and regional wall motion between both gated SPECT procedures had excellent correlation (LVEF, r = 0.943; LVEDV, r = 0.934; LVESV, r = 0.952; regional wall motion, kappa = 0.92). However, the correlations of global LV function and regional wall motion between each gated SPECT and LVG were significantly lower. Gated SPECT with (123)I-BMIPP showed the same interobserver validity as gated SPECT with (99m)Tc-tetrofosmin. Gated SPECT with (123)I-BMIPP provides high accuracy with regard to LV function and is sufficiently applicable for use in clinical SPECT. This technique can simultaneously reveal myocardial fatty acid metabolism and LV function, which may be useful to evaluate various cardiac diseases.

Right ventricular effects of intracoronary delivery of mesenchymal stem cells (MSC) in an animal model of pressure overload heart failure.

PubMed

Molina, Ezequiel J; Palma, Jon; Gupta, Dipin; Gaughan, John P; Houser, Steven; Macha, Mahender

2009-12-01

In a rat model of left ventricular pressure overload hypertrophy with biventricular failure, we studied the effects of intracoronary delivery of mesenchymal stem cells (MCS) upon right ventricular hemodynamic performance, profiles of local inflammation and apoptosis, and determinants of extracellular matrix remodeling. Sprague-Dawley rats underwent aortic banding and were followed by echocardiography. After a decrease in left ventricular fractional shortening of 25% from the baseline (relative 50% reduction), animals were randomized to an intracoronary injection of MSC (n=28) or PBS (n=20). Right ventricular hemodynamic assessment and measurement of local inflammatory markers, proapoptotic factors, and determinants of extracellular matrix remodeling were performed on post-transplantation day 7, 14, 21 or 28. MSC injection improved right ventricular systolic function in the MSC group compared to the control group (mean+/-SD, max dP/dt 772+/-272 mm Hg/s vs. 392+/-132 at 28 days, P<0.01). Diastolic function was similarly improved (mean+/-SD, max -dP/dt -558+/-171 mm Hg/s vs. -327+/-131 at 28 days, P<0.05). Right ventricular levels of IL-1, IL-6, TNF-alpha, bax, bak and p38 were significantly decreased in the MSC treated animals. Expression of MMP-3, MMP-6, MMP-9, TIMP-1 and TIMP-3 declined in the MSC group compared with controls after 28 days. In this model of left ventricular pressure overload hypertrophy and biventricular failure, intracoronary delivery of MSC was associated with an improvement in the right ventricular hemodynamic performance, profiles of local inflammation and apoptosis, and determinants of extracellular matrix remodeling.

Real-time adjustment of ventricular restraint therapy in heart failure.

PubMed

Ghanta, Ravi K; Lee, Lawrence S; Umakanthan, Ramanan; Laurence, Rita G; Fox, John A; Bolman, Ralph Morton; Cohn, Lawrence H; Chen, Frederick Y

2008-12-01

Current ventricular restraint devices do not allow for either the measurement or adjustment of ventricular restraint level. Periodic adjustment of restraint level post-device implantation may improve therapeutic efficacy. We evaluated the feasibility of an adjustable quantitative ventricular restraint (QVR) technique utilizing a fluid-filled polyurethane epicardial balloon to measure and adjust restraint level post-implantation guided by physiologic parameters. QVR balloons were implanted in nine ovine with post-infarction dilated heart failure. Restraint level was defined by the maximum restraint pressure applied by the balloon to the epicardium at end-diastole. An access line connected the balloon lumen to a subcutaneous portacath to allow percutaneous access. Restraint level was adjusted while left ventricular (LV) end-diastolic volume (EDV) and cardiac output was assessed with simultaneous transthoracic echocardiography. All nine ovine successfully underwent QVR balloon implantation. Post-implantation, restraint level could be measured percutaneously in real-time and dynamically adjusted by instillation and withdrawal of fluid from the balloon lumen. Using simultaneous echocardiography, restraint level could be adjusted based on LV EDV and cardiac output. After QVR therapy for 21 days, LV EDV decreased from 133+/-15 ml to 113+/-17 ml (p<0.05). QVR permits real-time measurement and physiologic adjustment of ventricular restraint therapy after device implantation.

The Use of Pediatric Ventricular Assist Devices in Children's Hospitals From 2000 to 2010: Morbidity, Mortality, and Hospital Charges.

PubMed

Mansfield, Robert T; Lin, Kimberly Y; Zaoutis, Theoklis; Mott, Antonio R; Mohamad, Zeinab; Luan, Xianqun; Kaufman, Beth D; Ravishankar, Chitra; Gaynor, J William; Shaddy, Robert E; Rossano, Joseph W

2015-07-01

The use of ventricular assist devices has increased dramatically in adult heart failure patients. However, the overall use, outcome, comorbidities, and resource utilization of ventricular assist devices in pediatric patients have not been well described. We sought to demonstrate that the use of ventricular assist devices in pediatric patients has increased over time and that mortality has decreased. A retrospective study of the Pediatric Health Information System database was performed for patients 20 years old or younger undergoing ventricular assist device placement from 2000 to 2010. None. Four hundred seventy-five pediatric patients were implanted with ventricular assist devices during the study period: 69 in 2000-2003 (era 1), 135 in 2004-2006 (era 2), and 271 in 2007-2010 (era 3). Median age at ventricular assist device implantation was 6.0 years (interquartile range, 0.5-13.8), and the proportion of children who were 1-12 years old increased from 29% in era 1 to 47% in era 3 (p = 0.002). The majority of patients had a diagnosis of cardiomyopathy; this increased from 52% in era 1 to 72% in era 3 (p = 0.003). Comorbidities included arrhythmias (48%), pulmonary hypertension (16%), acute renal failure (34%), cerebrovascular disease (28%), and sepsis/systemic inflammatory response syndrome (34%). Two hundred forty-seven patients (52%) underwent heart transplantation and 327 (69%) survived to hospital discharge. Hospital mortality decreased from 42% in era 1 to 25% in era 3 (p = 0.004). Median hospital length of stay increased (37 d [interquartile range, 12-64 d] in era 1 vs 69 d [interquartile range, 35-130] in era 3; p < 0.001) and median adjusted hospital charges increased ($630,630 [interquartile range, $227,052-$853,318] in era 1 vs $1,577,983 [interquartile range, $874,463-$2,280,435] in era 3; p < 0.001). Factors associated with increased mortality include age less than 1 year (odds ratio, 2.04; 95% CI, 1.01-3.83), acute renal failure (odds ratio, 2.1; 95% CI, 1.26-3.65), cerebrovascular disease (odds ratio, 2.1; 95% CI, 1.25-3.62), and extracorporeal membrane oxygenation (odds ratio, 3.16; 95% CI, 1.79-5.60). Ventricular assist device placement in era 3 (odds ratio, 0.3; 95% CI, 0.15-0.57) and a diagnosis of cardiomyopathy (odds ratio, 0.5; 95% CI, 0.32-0.84), were associated with decreased mortality. Large-volume centers had lower mortality (odds ratio, 0.55; 95% CI, 0.34-0.88), lower use of extracorporeal membrane oxygenation, and higher charges. The use of ventricular assist devices and survival after ventricular assist device placement in pediatric patients have increased over time, with a concomitant increase in resource utilization. Age under 1 year, certain noncardiac morbidities, and the use of extracorporeal membrane oxygenation are associated with worse outcomes. Lower mortality was seen at larger volume ventricular assist device centers.

Echocardiographic left ventricular masses in distance runners and weight lifters

NASA Technical Reports Server (NTRS)

Longhurst, J. C.; Gonyea, W. J.; Mitchell, J. H.; Kelly, A. R.

1980-01-01

The relationships of different forms of exercise training to left ventricular mass and body mass are investigated by echocardiographic studies of weight lifters, long-distance runners, and comparatively sized untrained control subjects. Left ventricular mass determinations by the Penn convention reveal increased absolute left ventricular masses in long-distance runners and competitive weight lifters with respect to controls matched for age, body weight, and body surface area, and a significant correlation between ventricular mass and lean body mass. When normalized to lean body mass, the ventricular masses of distance runners are found to be significantly higher than those of the other groups, suggesting that dynamic training elevates left ventricular mass compared to static training and no training, while static training increases ventricular mass only to the extent that lean body mass is increased.

Lung volumes, ventricular function and pulmonary arterial flow in children operated on for left-sided congenital diaphragmatic hernia: long-term results.

PubMed

Abolmaali, Nasreddin; Koch, Arne; Götzelt, Knut; Hahn, Gabriele; Fitze, Guido; Vogelberg, Christian

2010-07-01

To compare MRI-based functional pulmonary and cardiac measurements in the long-term follow-up of children operated on for left-sided congenital diaphragmatic hernia (CDH) with age- and body size-matched healthy controls. Twelve children who received immediate postnatal surgery for closure of isolated left-sided CDH were included and received basic medical examinations, pulmonary function testing and echocardiography. MRI included measurement of lung volume, ventricular function assessment and velocity-encoded imaging of the pulmonary arteries and was compared with the data for 12 healthy children matched for age and body size. While patients' clinical test results were not suspicious, comparison between the MRI data for patients and those for healthy controls revealed significant differences. In patients, the volumes of the left lungs were increased and the tidal volume was larger on the right side. While the stroke volumes of both ventricles were reduced, heart rate and ejection fraction were increased. Flow, acceleration time and cross-sectional area of the left pulmonary artery were reduced. Functional MRI detected pulmonary and cardiac findings in the late follow-up of CDH children which may be missed by standard clinical methods and might be relevant for decisions regarding late outcome and treatment.

Right Ventricular Perfusion: Physiology and Clinical Implications.

PubMed

Crystal, George J; Pagel, Paul S

2018-01-01

Regulation of blood flow to the right ventricle differs significantly from that to the left ventricle. The right ventricle develops a lower systolic pressure than the left ventricle, resulting in reduced extravascular compressive forces and myocardial oxygen demand. Right ventricular perfusion has eight major characteristics that distinguish it from left ventricular perfusion: (1) appreciable perfusion throughout the entire cardiac cycle; (2) reduced myocardial oxygen uptake, blood flow, and oxygen extraction; (3) an oxygen extraction reserve that can be recruited to at least partially offset a reduction in coronary blood flow; (4) less effective pressure-flow autoregulation; (5) the ability to downregulate its metabolic demand during coronary hypoperfusion and thereby maintain contractile function and energy stores; (6) a transmurally uniform reduction in myocardial perfusion in the presence of a hemodynamically significant epicardial coronary stenosis; (7) extensive collateral connections from the left coronary circulation; and (8) possible retrograde perfusion from the right ventricular cavity through the Thebesian veins. These differences promote the maintenance of right ventricular oxygen supply-demand balance and provide relative resistance to ischemia-induced contractile dysfunction and infarction, but they may be compromised during acute or chronic increases in right ventricle afterload resulting from pulmonary arterial hypertension. Contractile function of the thin-walled right ventricle is exquisitely sensitive to afterload. Acute increases in pulmonary arterial pressure reduce right ventricular stroke volume and, if sufficiently large and prolonged, result in right ventricular failure. Right ventricular ischemia plays a prominent role in these effects. The risk of right ventricular ischemia is also heightened during chronic elevations in right ventricular afterload because microvascular growth fails to match myocyte hypertrophy and because microvascular dysfunction is present. The right coronary circulation is more sensitive than the left to α-adrenergic-mediated constriction, which may contribute to its greater propensity for coronary vasospasm. This characteristic of the right coronary circulation may increase its vulnerability to coronary vasoconstriction and impaired right ventricular perfusion during administration of α-adrenergic receptor agonists.

Right Ventricular Ejection Fraction Is Incremental to Left Ventricular Ejection Fraction for the Prediction of Future Arrhythmic Events in Patients With Systolic Dysfunction.

PubMed

Mikami, Yoko; Jolly, Umjeet; Heydari, Bobak; Peng, Mingkai; Almehmadi, Fahad; Zahrani, Mohammed; Bokhari, Mahmoud; Stirrat, John; Lydell, Carmen P; Howarth, Andrew G; Yee, Raymond; White, James A

2017-01-01

Left ventricular ejection fraction remains the primary risk stratification tool used in the selection of patients for implantable cardioverter defibrillator therapy. However, this solitary marker fails to identify a substantial portion of patients experiencing sudden cardiac arrest. In this study, we examined the incremental value of considering right ventricular ejection fraction for the prediction of future arrhythmic events in patients with systolic dysfunction using the gold standard of cardiovascular magnetic resonance. Three hundred fourteen consecutive patients with ischemic cardiomyopathy or nonischemic dilated cardiomyopathy undergoing cardiovascular magnetic resonance were followed for the primary outcome of sudden cardiac arrest or appropriate implantable cardioverter defibrillator therapy. Blinded quantification of left ventricular and right ventricular (RV) volumes was performed from standard cine imaging. Quantification of fibrosis from late gadolinium enhancement imaging was incrementally performed. RV dysfunction was defined as right ventricular ejection fraction ≤45%. Among all patients (164 ischemic cardiomyopathy, 150 nonischemic dilated cardiomyopathy), the mean left ventricular ejection fraction was 32±12% (range, 6-54%) with mean right ventricular ejection fraction of 48±15% (range, 7-78%). At a median of 773 days, 49 patients (15.6%) experienced the primary outcome (9 sudden cardiac arrest, 40 appropriate implantable cardioverter defibrillator therapies). RV dysfunction was independently predictive of the primary outcome (hazard ratio=2.98; P=0.002). Among those with a left ventricular ejection fraction >35% (N=121; mean left ventricular ejection fraction, 45±6%), RV dysfunction provided an adjusted hazard ratio of 4.2 (P=0.02). RV dysfunction is a strong, independent predictor of arrhythmic events. Among patients with mild to moderate LV dysfunction, a cohort greatly contributing to global sudden cardiac arrest burden, this marker provides robust discrimination of high- versus low-risk subjects. © 2017 American Heart Association, Inc.

Does dapagliflozin regress left ventricular hypertrophy in patients with type 2 diabetes? A prospective, double-blind, randomised, placebo-controlled study.

PubMed

Brown, Alexander J M; Lang, Chim; McCrimmon, Rory; Struthers, Allan

2017-08-23

Patients with diabetes have a two to fourfold increased risk for development of and death from cardiovascular disease [CVD]. The current oral hypoglycaemic agents result in limited reduction in this cardiovascular risk. Sodium glucose linked co-transporter type 2 [SGLT2] inhibitors are a relatively new class of antidiabetic agent that have been shown to have potential cardiovascular benefits. In support of this, the EMPA-REG trial showed a striking 38% and 35% reduction in cardiovascular mortality and heart failure [HF] hospitalisation respectively. The exact mechanism (s) responsible for these effects remain (s) unclear. One potential mechanism is regression of Left ventricular hypertrophy (LVH). The DAPA-LVH trial is a prospective, double-blind, randomised, placebo-controlled 'proof of concept' single-centre study that has been ongoing since January 2017. It is designed specifically to assess whether the SGLT2 inhibitor dapagliflozin regresses left ventricular [LV] mass in patients with diabetes and left ventricular hypertrophy [LVH]. We are utilising cardiac and abdominal magnetic resonance imaging [MRI] and ambulatory blood pressure monitoring to quantify the cardiovascular and systemic effects of dapagliflozin 10 mg once daily against standard care over a 1 year observation period. The primary endpoint is to detect the changes in LV mass. The secondary outcomes are to assess the changes in, LV volumes, blood pressure, weight, visceral and subcutaneous fat. This trial will be able to determine if SGLT2 inhibitor therapy reduces LV mass in patient with diabetes and LVH thereby strengthening their position as oral hypoglycaemic agents with cardioprotective benefits. Clinical Trials.gov: NCT02956811 . Registered November 2016.

Magnetic Resonance Imaging as a Predictor of Survival Free of Life-Threatening Arrhythmias and Transplantation in Cardiac Sarcoidosis.

PubMed

Ekström, Kaj; Lehtonen, Jukka; Hänninen, Helena; Kandolin, Riina; Kivistö, Sari; Kupari, Markku

2016-05-02

Cardiac magnetic resonance imaging has a key role in today's diagnosis of cardiac sarcoidosis. We set out to investigate whether cardiac magnetic resonance imaging also helps predict outcome in cardiac sarcoidosis. Our work involved 59 patients with cardiac sarcoidosis (38 female, mean age 46±10 years) seen at our hospital since February 2004 and followed up after contrast-enhanced cardiac magnetic resonance imaging. The extent of myocardial late gadolinium enhancement (measured as percentage of left ventricular mass), the volumes and ejection fractions of the left and right ventricles, and the thickness of the basal interventricular septum were determined and analyzed for prognostic significance. By April 2015, 23 patients had reached the study's end point, consisting of a composite of cardiac death (n=3), cardiac transplantation (n=1), and occurrence of life-threatening ventricular tachyarrhythmias (n=19; ventricular fibrillation in 5 and sustained ventricular tachycardia in 14 patients). In univariate analysis, myocardial extent of late gadolinium enhancement predicted event-free survival, as did scar-like thinning (<4 mm) of the basal interventricular septum and the ejection fraction of the right ventricle (P<0.05 for all). In multivariate Cox regression analysis, extent of late gadolinium enhancement was the only independent predictor of outcome events on cardiac magnetic resonance imaging, with a hazard ratio of 2.22 per tertile (95% CI 1.07-4.59). An extent of late gadolinium enhancement >22% (third tertile) had positive and negative predictive values for serious cardiac events of 75% and 76%, respectively. Findings on cardiac magnetic resonance imaging and the extent of myocardial late gadolinium enhancement in particular help predict serious cardiac events in cardiac sarcoidosis. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Assessment of Diastolic Function in Single Ventricle Patients Following the Fontan Procedure

PubMed Central

Margossian, Renee; Sleeper, Lynn A.; Pearson, Gail D.; Barker, Piers C.; Mertens, Luc; Quartermain, Michael D.; Su, Jason T.; Shirali, Girish; Chen, Shan; Colan, Steven D.

2016-01-01

Objectives Patients with functional single ventricles (FSV) following the Fontan procedure have abnormal cardiac mechanics. We sought to determine factors that influence diastolic function and to describe associations of diastolic function with current clinical status. Methods Echocardiograms were obtained as part of the Pediatric Heart Network Fontan Cross-Sectional Study. Diastolic function grade (DFG) was assessed as normal (grade 0), impaired relaxation (grade 1), pseudonormalization (grade 2), restrictive (grade 3). Studies were also classified dichotomously (restrictive pattern present or absent). Relationships between DFG and pre-Fontan variables (e.g., ventricular morphology, age at Fontan, history of volume-unloading surgery), and current status (e.g., systolic function, valvar regurgitation, exercise performance) were explored. Results DFG was calculable in 326/546 subjects (60%); mean age = 11.7±3.3 years. Overall, 32% of patients had grade 0, 9% grade 1, 37% grade 2, and 22% grade 3. Although there was no association between ventricular morphology and DFG, there was an association between ventricular morphology and E’, which was lowest in those with right ventricular morphology (p<.001); this association remained significant when using z-scores adjusted for age (p=<.001). DFG was associated with achieving maximal effort on exercise testing (p=.004); the majority (64%) of those not achieving maximal effort had DFG 2 or 3.No additional significant associations of DFG with laboratory or clinical measures were identified. Conclusion Assessment of diastolic function by current algorithms results in a high percentage of patients with abnormal DFG, but we found few clinically or statistically significant associations. This may imply a lack of impact of abnormal diastolic function upon clinical outcome in this cohort, or may indicate that the methodology may not be applicable to pediatric FSV patients. PMID:27624592

Acute control of pulmonary regurgitation with a balloon "valve". An experimental investigation.

PubMed

Siwek, L G; Applebaum, R E; Jones, M; Clark, R E

1985-09-01

Operations for certain congenital cardiac lesions can produce pulmonary regurgitation. Pulmonary regurgitation contributes to right ventricular dysfunction, which may cause early postoperative morbidity and mortality. To ameliorate the problems of pulmonary regurgitation during the early postoperative period, we evaluated a method for its acute control. Complete pulmonary valvectomy was performed utilizing inflow occlusion in eight sheep. A catheter with a 15 ml spherical balloon was positioned in the pulmonary arterial trunk; its inflation and deflation were regulated by an intra-aortic balloon pump unit. Blood flow from the pulmonary arterial trunk and forward and regurgitant fraction were determined from electromagnetic flow transducer recordings. The regurgitant fraction with uncontrolled pulmonary regurgitation was 38% +/- 3% (forward flow = 42 +/- 5 ml/beat and regurgitant flow = 16 +/- 2 ml/beat). Inflation of the balloon during diastole was timed to completely eliminate pulmonary regurgitation. This balloon control of pulmonary regurgitation increased pulmonary arterial diastolic pressure from 12 +/- 1 to 17 +/- 1 mm Hg (p less than 0.0001) and decreased pulmonary arterial systolic pressure from 31 +/- 3 to 27 +/- 1 mm Hg (p = 0.06). Pulmonary arterial pulse pressure decreased from 19 +/- 3 to 9 +/- 1 mm Hg (p less than 0.003). Elimination of pulmonary regurgitation decreased right ventricular stroke volume (25 +/- 3 versus 42 +/- 5 ml/beat, p less than 0.0002) and resulted in a 46% reduction in right ventricular stroke work (5.0 +/- 0.6 versus 9.4 +/- 1.0 gm-m/beat, p less than 0.001) with no change in net forward pulmonary artery flow. Thus, acute pulmonary regurgitation can be controlled and this control improves overall hemodynamic status and decreases right ventricular work.

High Right Ventricular Stroke Work Index Is Associated with Worse Kidney Function in Patients with Heart Failure with Preserved Ejection Fraction.

PubMed

Kanjanahattakij, Napatt; Sirinvaravong, Natee; Aguilar, Francisco; Agrawal, Akanksha; Krishnamoorthy, Parasuram; Gupta, Shuchita

2018-01-01

In patients with heart failure with preserved ejection fraction (HFpEF), worse kidney function is associated with worse overall cardiac mechanics. Right ventricular stroke work index (RVSWI) is a parameter of right ventricular function. The aim of our study was to determine the relationship between RVSWI and glomerular filtration rate (GFR) in patients with HFpEF. This was a single-center cross-sectional study. HFpEF is defined as patients with documented heart failure with ejection fraction > 50% and pulmonary wedge pressure > 15 mm Hg from right heart catheterization. RVSWI (normal value 8-12 g/m/beat/m2) was calculated using the formula: RVSWI = 0.0136 × stroke volume index × (mean pulmonary artery pressure - mean right atrial pressure). Univariate and multivariate linear regression analysis was performed to study the correlation between RVSWI and GFR. Ninety-one patients were included in the study. The patients were predominantly female (n = 64, 70%) and African American (n = 61, 67%). Mean age was 66 ± 12 years. Mean GFR was 59 ± 35 mL/min/1.73 m2. Mean RVSWI was 11 ± 6 g/m/beat/m2. Linear regression analysis showed that there was a significant independent inverse relationship between RVSWI and GFR (unstandardized coefficient = -1.3, p = 0.029). In the subgroup with combined post and precapillary pulmonary hypertension (Cpc-PH) the association remained significant (unstandardized coefficient = -1.74, 95% CI -3.37 to -0.11, p = 0.04). High right ventricular workload indicated by high RVSWI is associated with worse renal function in patients with Cpc-PH. Further prospective studies are needed to better understand this association. © 2018 S. Karger AG, Basel.

Cardiac troponin I for the prediction of functional recovery and left ventricular remodelling following primary percutaneous coronary intervention for ST-elevation myocardial infarction.

PubMed

Hallén, Jonas; Jensen, Jesper K; Fagerland, Morten W; Jaffe, Allan S; Atar, Dan

2010-12-01

To investigate the ability of cardiac troponin I (cTnI) to predict functional recovery and left ventricular remodelling following primary percutaneous coronary intervention (pPCI) in ST-elevation myocardial infarction (STEMI). Post hoc study extending from randomised controlled trial. 132 patients with STEMI receiving pPCI. Left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volume index (EDVI and ESVI) and changes in these parameters from day 5 to 4 months after the index event. Cardiac magnetic resonance examination performed at 5 days and 4 months for evaluation of LVEF, EDVI and ESVI. cTnI was sampled at 24 and 48 h. In linear regression models adjusted for early (5 days) assessment of LVEF, ESVI and EDVI, single-point cTnI at either 24 or 48 h were independent and strong predictors of changes in LVEF (p<0.01), EDVI (p<0.01) and ESVI (p<0.01) during the follow-up period. In a logistic regression analysis for prediction of an LVEF below 40% at 4 months, single-point cTnI significantly improved the prognostic strength of the model (area under the curve = 0.94, p<0.01) in comparison with the combination of clinical variables and LVEF at 5 days. Single-point sampling of cTnI after pPCI for STEMI provides important prognostic information on the time-dependent evolution of left ventricular function and volumes.

Left ventricular systolic function in sickle cell anaemia: an echocardiographic evaluation in adult Nigerian patients.

PubMed

Ejim, Emmanuel; Oguanobi, Nelson

2016-09-01

Reliable diagnostic measures for the evaluation of left ventricular systolic performance in the setting of altered myocardial loading characteristics in sickle cell anaemia remains unresolved. The study was designed to assess left ventricular systolic function in adult sickle cell patients using non-invasive endsystolic stress - end-systolic volume index ratio. A descriptive cross sectional comparative study was done using 52 patients recruited at the adult sickle cell anaemia clinic of the University of Nigeria Teaching Hospital Enugu. An equal number of age and sex-matched healthy volunteers served as controls. All the participants had haematocrit estimation, haemoglobin electrophoresis, as well as echocardiographic evaluation. The mean age of the patients and controls were 23.93 ± 5.28 (range 18-42) and 24.17 ± 4.39 (range 19 -42) years respectively, (t = 0.262; p= .794). No significant difference was seen in estimate of fractional shortening, and ejection fraction. The cardiac out-put, cardiac index and velocity of circumferential shortening were all significantly increased in the cases compared with the controls. The end systolic stress - end systolic volume index ratio (ESS/ESVI) was significantly lower in cases than controls. There were strong positive correlation between the ejection phase indices (ejection fraction and fractional shortening) and end systolic stress and ESS/ESVI. The study findings suggest the presence of left ventricular systolic dysfunction in adult sickle cell anaemia. This is best detected using the loading-pressures independent force-length relationship expressed in ESS/ESVI ratio.

Quantification of the relative contribution of the different right ventricular wall motion components to right ventricular ejection fraction: the ReVISION method.

PubMed

Lakatos, Bálint; Tősér, Zoltán; Tokodi, Márton; Doronina, Alexandra; Kosztin, Annamária; Muraru, Denisa; Badano, Luigi P; Kovács, Attila; Merkely, Béla

2017-03-27

Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction's ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.

Echocardiographic findings in professional hockey players

PubMed Central

Fazel, Poorya; Roberts, Brad J.; Brooks, John

2009-01-01

Tissue Doppler imaging was used to evaluate the physiological and morphological response in athletes whose cardiac system must not only adapt to intense cardiovascular demands but also support sudden, transient changes in cardiac output. A total of 45 professional hockey players with a mean age of 24 years underwent a baseline transthoracic echocardiographic protocol after a typical morning workout; 12 healthy age- and gender-matched controls were evaluated as a means of comparison. The athletes in this study possessed larger left ventricular diastolic and systolic dimensions than the control group (5.5 ± 0.4 vs 4.9 ± 0.4 cm and 3.9 ± 0.4 vs 3.3 ± 0.4 cm, P < 0.0001). The increase in athletes' septal and posterior wall thickness was not substantial, nor was there a significant difference in left ventricular ejection fraction. The athletes demonstrated consistently larger left ventricular end-diastolic volume (196 ± 34 vs 136 ± 23 mL, P < 0.001) and end-systolic volume (87 ± 20 vs 57 ± 12 mL, P < 0.0001). They also had lower annular septal and lateral early diastolic and systolic tissue Doppler velocities compared with the control group. Thus, characteristic myocardial changes previously reported in elite athletes were also represented in professional hockey players. The lower left ventricular tissue Doppler velocities was a relatively unique finding and probably a consequence of lower postexertion preload levels compared with controls who were measured at rest. PMID:19633740

[Cardiac Synchronization Function Estimation Based on ASM Level Set Segmentation Method].

PubMed

Zhang, Yaonan; Gao, Yuan; Tang, Liang; He, Ying; Zhang, Huie

At present, there is no accurate and quantitative methods for the determination of cardiac mechanical synchronism, and quantitative determination of the synchronization function of the four cardiac cavities with medical images has a great clinical value. This paper uses the whole heart ultrasound image sequence, and segments the left & right atriums and left & right ventricles of each frame. After the segmentation, the number of pixels in each cavity and in each frame is recorded, and the areas of the four cavities of the image sequence are therefore obtained. The area change curves of the four cavities are further extracted, and the synchronous information of the four cavities is obtained. Because of the low SNR of Ultrasound images, the boundary lines of cardiac cavities are vague, so the extraction of cardiac contours is still a challenging problem. Therefore, the ASM model information is added to the traditional level set method to force the curve evolution process. According to the experimental results, the improved method improves the accuracy of the segmentation. Furthermore, based on the ventricular segmentation, the right and left ventricular systolic functions are evaluated, mainly according to the area changes. The synchronization of the four cavities of the heart is estimated based on the area changes and the volume changes.

Cardiopulmonary physiology: why the heart and lungs are inextricably linked.

PubMed

Verhoeff, Kevin; Mitchell, Jamie R

2017-09-01

Because the heart and lungs are confined within the thoracic cavity, understanding their interactions is integral for studying each system. Such interactions include changes in external constraint to the heart, blood volume redistribution (venous return), direct ventricular interaction (DVI), and left ventricular (LV) afterload. During mechanical ventilation, these interactions can be amplified and result in reduced cardiac output. For example, increased intrathoracic pressure associated with mechanical ventilation can increase external constraint and limit ventricular diastolic filling and, therefore, output. Similarly, high intrathoracic pressures can alter blood volume distribution and limit diastolic filling of both ventricles while concomitantly increasing pulmonary vascular resistance, leading to increased DVI, which may further limit LV filling. While LV afterload is generally considered to decrease with increased intrathoracic pressure, the question arises if the reduced LV afterload is primarily a consequence of a reduced LV preload. A thorough understanding of the interaction between the heart and lungs can be complicated but is essential for clinicians and health science students alike. In this teaching review, we have attempted to highlight the present understanding of certain salient aspects of cardiopulmonary physiology and pathophysiology, as well as provide a resource for multidisciplined health science educators and students. Copyright © 2017 the American Physiological Society.

The Dark Side of the Moon: The Right Ventricle

PubMed Central

Foschi, Massimiliano; Di Mauro, Michele; Tancredi, Fabrizio; Capparuccia, Carlo; Petroni, Renata; Leonzio, Luigi; Romano, Silvio; Gallina, Sabina; Penco, Maria; Cibelli, Mario; Calafiore, Antonio

2017-01-01

The aim of this review article is to summarize current knowledge of the pathophysiology underlying right ventricular failure (RVF), focusing, in particular, on right ventricular assessment and prognosis. The right ventricle (RV) can tolerate volume overload well, but is not able to sustain pressure overload. Right ventricular hypertrophy (RVH), as a response to increased afterload, can be adaptive or maladaptive. The easiest and most common way to assess the RV is by two-dimensional (2D) trans-thoracic echocardiography measuring surrogate indexes, such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and tissue Doppler velocity of the lateral aspect of the tricuspid valvular plane. However, both volumes and function are better estimated by 3D echocardiography and cardiac magnetic resonance (CMR). The prognostic role of the RV in heart failure (HF), pulmonary hypertension (PH), acute myocardial infarction (AMI), and cardiac surgery has been overlooked for many years. However, several recent studies have placed much greater importance on the RV in prognostic assessments. In conclusion, RV dimensions and function should be routinely assessed in cardiovascular disease, as RVF has a significant impact on disease prognosis. In the presence of RVF, different therapeutic approaches, either pharmacological or surgical, may be beneficial. PMID:29367547

Perflurooctanoic Acid Induces Developmental Cardiotoxicity in ...

EPA Pesticide Factsheets

Perfluorooctanoic acid (PFOA) is a widespread environmental contaminant that is detectable in serum of the general U.S. population. PFOA is a known developmental toxicant that induces mortality in mammalian embryos and is thought to induce toxicity via interaction with the peroxisome proliferator activated receptor alpha (PPAR_). As the cardiovascular system is crucial for embryonic survival, PFOA-induced effects on the heart may partially explain embryonic mortality. To assess impacts of PFOA exposure on the developing heart in an avian model, we used histopathology and immunohistochemical staining for myosin to assess morphological alterations in 19-day-old chicken embryo hearts after PFOA exposure. Additionally, echocardiography and cardiac myofibril ATPase activity assays were used to assess functional alterations in 1-day-old hatchling chickens following developmental PFOA exposure. Overall thinning and thinning of a dense layer of myosin in the right ventricular wall were observed in PFOA-exposed chicken embryo hearts. Alteration of multiple cardiac structural and functional parameters, including left ventricular wall thickness, left ventricular volume, heart rate, stroke volume, and ejection fraction were detected with echocardiography in the exposed hatchling chickens. Assessment of ATPase activity indicated that the ratio of cardiac myofibril calcium-independent ATPase activity to calcium-dependent ATPase activity was not affected, which suggests that d

Enhanced ventricular pump function and decreased reservoir backflow sustain rise in pulmonary blood flow after reduction of lung liquid volume in fetal lambs.

PubMed

Smolich, Joseph J

2014-02-15

Although a reduction in lung liquid volume increases fetal pulmonary blood flow, the changes in central flow patterns that sustain this increased pulmonary perfusion are unknown. To address this issue, eight anesthetized late-gestation fetal sheep were instrumented with pulmonary trunk (PT), ductus arteriosus (DA), and left pulmonary artery (PA) micromanometer catheters and transit-time flow probes, with blood flow profile and wave intensity analyses performed at baseline and after withdrawal of lung liquid via an endotracheal tube. Reducing lung liquid volume by 19 ± 6 ml/kg (mean ± SD) augmented right ventricular power by 34% (P < 0.001), with distribution of an accompanying increase in mean PT blood flow (245 ± 63 ml/min, P < 0.001) to the lungs (169 ± 91 ml/min, P = 0.001) and across the DA (77 ± 92 ml/min, P = 0.04). However, although PT and DA flow increments were confined to systole and were related to an increased magnitude of flow-increasing, forward-running compression waves, the rise in PA flow spanned both systole (108 ± 66 ml/min) and diastole (61 ± 32 ml/min). Flow profile analysis showed that the step-up in PA diastolic flow was associated with diminished PA diastolic backflow and accompanied by a lesser degree of diastolic right-to-left DA shunting. These data suggest that an increased pulmonary blood flow after reduction of lung liquid volume is associated with substantial changes in PT-DA-PA interactions and underpinned by two main factors: 1) enhanced right ventricular pump function that increases PA systolic inflow and 2) decreased PA diastolic backflow that arises from a fundamental change in PA reservoir function, thereby resulting in greater passage of systolic inflow through the lungs.

Load dependence of the effective regurgitant orifice area in a sheep model of aortic regurgitation.

PubMed

Reimold, S C; Byrne, J G; Caguioa, E S; Lee, C C; Laurence, R G; Peigh, P S; Cohn, L H; Lee, R T

1991-10-01

Treatment of patients with aortic regurgitation with vasodilators reduces regurgitant volume, ventricular dilation and left ventricular mass. Although these effects are presumably due to afterload reduction, it is also possible that the aortic regurgitant orifice area is not constant. To test the latter hypothesis, aortic regurgitation was created in 10 open chest sheep by partial resection of the noncoronary leaflet under direct visualization. Regurgitant flow was measured with an aortic supravalvular electromagnetic probe; aortic and left ventricular pressures were measured with catheter-tipped micromanometer pressure transducers. The effective regurgitant orifice area was calculated by a modification of the continuity equation in a manner similar to the Gorlin equation. The regurgitant orifice area was measured three times: after aortic regurgitation was created, after mean arterial pressure was increased by 15 to 25 mm Hg with intravenous dopamine and after mean arterial pressure was reduced by 15 to 25 mm Hg with intravenous sodium nitroprusside. Comparison of regurgitant volumes and areas obtained after creation of aortic regurgitation and at the conclusion of the experiment in the absence of dopamine or sodium nitroprusside demonstrated no significant change over time. Dopamine administration was associated with an 86 +/- 81% increase in regurgitant volume (p less than 0.01) and a 38 +/- 44% increase in regurgitant orifice area (p less than 0.01). Sodium nitroprusside administration resulted in a 51 +/- 14% decrease in regurgitant volume (p less than 0.001) and a 28 +/- 21% reduction in regurgitant orifice area (p = 0.007). In this model of acute aortic regurgitation, the effective regurgitant orifice area was altered by increasing or decreasing the aortic transvalvular pressure gradient.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of Genotype on Structural Atrial Abnormalities and Atrial Fibrillation or Flutter in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy.

PubMed

Bourfiss, Mimount; Te Riele, Anneline S J M; Mast, Thomas P; Cramer, Maarten J; VAN DER Heijden, Jeroen F; VAN Veen, Toon A B; Loh, Peter; Dooijes, Dennis; Hauer, Richard N W; Velthuis, Birgitta K

2016-12-01

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is associated with desmosomal mutations. Although desmosomal disruption affects both ventricles and atria, little is known about atrial involvement in ARVD/C. To describe the extent and clinical significance of structural atrial involvement and atrial arrhythmias (AA) in ARVD/C stratified by genotype. We included 71 patients who met ARVD/C Task Force Criteria and underwent cardiac magnetic resonance (CMR) imaging and molecular genetic analysis. Indexed atrial end-diastolic volume and area-length-ejection-fraction (ALEF) were evaluated on CMR and compared to controls with idiopathic right ventricular outflow tract tachycardia (n = 40). The primary outcome was occurrence of AA (atrial fibrillation or atrial flutter) during follow-up, recorded by 12-lead ECG, Holter monitoring or implantable cardioverter defibrillator (ICD) interrogation. Patients harbored a desmosomal plakophilin-2 (PKP2) (n = 37) or nondesmosomal phospholamban (PLN) (n = 14) mutation. In 20 subjects, no pathogenic mutation was identified. Compared to controls, right atrial (RA) volumes were reduced in PKP2 (P = 0.002) and comparable in PLN (P = 0.441) mutation carriers. In patients with no mutation identified, RA (P = 0.011) and left atrial (P = 0.034) volumes were increased. Bi-atrial ALEF showed no significant difference between the groups. AA were experienced by 27% of patients and occurred equally among PKP2 (30%) and no mutation identified patients (30%), but less among PLN mutation carriers (14%). Genotype influences atrial volume and occurrence of AA in ARVD/C. While the incidence of AA is similar in PKP2 mutation carriers and patients with no mutation identified, PKP2 mutation carriers have significantly smaller atria. This suggests a different arrhythmogenic mechanism. © 2016 Wiley Periodicals, Inc.

Effect of antioxidant therapy with dl-alpha-tocopherol on cardiovascular structure in experimental renal failure.

PubMed

Amann, Kerstin; Törnig, Johannes; Buzello, Mareike; Kuhlmann, Alexander; Gross, Marie-Luise; Adamczak, Marcin; Buzello, Moriz; Ritz, Eberhard

2002-09-01

Chronic renal failure is characterized by remodeling of the structure of the heart and the vasculature, for example, left ventricular hypertrophy, myocardial fibrosis, capillary/myocyte mismatch, as well as thickening of intramyocardial arteries and of peripheral arteries and veins. Furthermore, uremia is a state of increased oxygen stress. It was the purpose of this study to examine whether these findings are interrelated. To investigate whether antioxidative therapy with dl-alpha-tocopherol (Toco; vitamin E) interferes with the development of abnormal cardiovascular structure in experimental renal failure, 28 male Sprague-Dawley rats were subjected to partial renal ablation (subtotal nephrectomy, SNX) or to sham operation (sham). SNX were either left untreated or received the antioxidant Toco (2 x 1500 IE/kg BW/week in the pellets). Blood pressure was measured using tail plethysmography. The experiment was terminated after 12 weeks. Heart and left ventricular weight were determined and the following parameters were measured using morphometry and stereology: volume densities of cardiomyocytes, capillaries and non-vascular interstitium; length density and total length of cardiac capillaries, wall thickness of intramyocardial arterioles and of the aorta. Systolic blood pressure and body weight were comparable in all groups. Treatment with Toco led to significantly increased plasma concentrations of Toco. Left ventricular weight and wall thickness of intramyocardial arteries were significantly higher in both SNX groups compared to sham controls. Volume density of the cardiac interstitial tissue was significantly higher in untreated SNX than in Toco treated SNX and sham control rats. Length density of capillaries was significantly lower in untreated SNX than in control rats; however, the values were significantly higher, and even higher than in sham controls, when SNX were treated with Toco. Treatment with the antioxidant dl-alpha-tocopherol prevented cardiomyocyte/capillary mismatch, and to some extent also myocardial fibrosis in rats with renal failure. The results point to a role of oxidative stress in the genesis of myocardial interstitial fibrosis and capillary deficit of the heart.

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

Stimulation of Single Isolated Adult Ventricular Myocytes within a Low Volume Using a Planar Microelectrode Array

PubMed Central

Klauke, Norbert; Smith, Godfrey L.; Cooper, Jon

2003-01-01

Microchannels (40-μm wide, 10-μm high, 10-mm long, 70-μm pitch) were patterned in the silicone elastomer, polydimethylsiloxane on a microscope coverslip base. Integrated within each microchamber were individually addressable stimulation electrodes (40-μm wide, 20-μm long, 100-nm thick) and a common central pseudo-reference electrode (60-μm wide, 500-μm long, 100-nm thick). Isolated rabbit ventricular myocytes were introduced into the chamber by micropipetting and subsequently capped with a layer of mineral oil, thus creating limited volumes of saline around individual myocytes that could be varied from 5 nL to 100 pL. Excitation contraction coupling was studied by monitoring myocyte shortening and intracellular Ca2+ transients (using Fluo-3 fluorescence) . The amplitude of stimulated myocyte shortening and Ca2+ transients remained constant for 90 min in the larger volume (5 nL) configuration, although the shortening (but not the Ca2+ transient) amplitude gradually decreased to 20% of control within 60 min in the low volume (100 pL) arrangement. These studies indicate a lower limit for the extracellular volume required to stimulate isolated adult cardiac myocytes. Whereas this arrangement could be used to create a screening assay for drugs, individual microchannels (100 pL) can also be used to study the effects of limited extracellular volume on the contractility of single cardiac myocytes. PMID:12944291

Studying ventricular abnormalities in mild cognitive impairment with hyperbolic Ricci flow and tensor-based morphometry.

PubMed

Shi, Jie; Stonnington, Cynthia M; Thompson, Paul M; Chen, Kewei; Gutman, Boris; Reschke, Cole; Baxter, Leslie C; Reiman, Eric M; Caselli, Richard J; Wang, Yalin

2015-01-01

Mild Cognitive Impairment (MCI) is a transitional stage between normal aging and dementia and people with MCI are at high risk of progression to dementia. MCI is attracting increasing attention, as it offers an opportunity to target the disease process during an early symptomatic stage. Structural magnetic resonance imaging (MRI) measures have been the mainstay of Alzheimer's disease (AD) imaging research, however, ventricular morphometry analysis remains challenging because of its complicated topological structure. Here we describe a novel ventricular morphometry system based on the hyperbolic Ricci flow method and tensor-based morphometry (TBM) statistics. Unlike prior ventricular surface parameterization methods, hyperbolic conformal parameterization is angle-preserving and does not have any singularities. Our system generates a one-to-one diffeomorphic mapping between ventricular surfaces with consistent boundary matching conditions. The TBM statistics encode a great deal of surface deformation information that could be inaccessible or overlooked by other methods. We applied our system to the baseline MRI scans of a set of MCI subjects from the Alzheimer's Disease Neuroimaging Initiative (ADNI: 71 MCI converters vs. 62 MCI stable). Although the combined ventricular area and volume features did not differ between the two groups, our fine-grained surface analysis revealed significant differences in the ventricular regions close to the temporal lobe and posterior cingulate, structures that are affected early in AD. Significant correlations were also detected between ventricular morphometry, neuropsychological measures, and a previously described imaging index based on fluorodeoxyglucose positron emission tomography (FDG-PET) scans. This novel ventricular morphometry method may offer a new and more sensitive approach to study preclinical and early symptomatic stage AD. Copyright © 2014 Elsevier Inc. All rights reserved.

STUDYING VENTRICULAR ABNORMALITIES IN MILD COGNITIVE IMPAIRMENT WITH HYPERBOLIC RICCI FLOW AND TENSOR-BASED MORPHOMETRY

PubMed Central

Shi, Jie; Stonnington, Cynthia M.; Thompson, Paul M.; Chen, Kewei; Gutman, Boris; Reschke, Cole; Baxter, Leslie C.; Reiman, Eric M.; Caselli, Richard J.; Wang, Yalin

2014-01-01

Mild Cognitive Impairment (MCI) is a transitional stage between normal aging and dementia and people with MCI are at high risk of progression to dementia. MCI is attracting increasing attention, as it offers an opportunity to target the disease process during an early symptomatic stage. Structural magnetic resonance imaging (MRI) measures have been the mainstay of Alzheimer’s disease (AD) imaging research, however, ventricular morphometry analysis remains challenging because of its complicated topological structure. Here we describe a novel ventricular morphometry system based on the hyperbolic Ricci flow method and tensor-based morphometry (TBM) statistics. Unlike prior ventricular surface parameterization methods, hyperbolic conformal parameterization is angle-preserving and does not have any singularities. Our system generates a one-to-one diffeomorphic mapping between ventricular surfaces with consistent boundary matching conditions. The TBM statistics encode a great deal of surface deformation information that could be inaccessible or overlooked by other methods. We applied our system to the baseline MRI scans of a set of MCI subjects from the Alzheimer’s Disease Neuroimaging Initiative (ADNI: 71 MCI converters vs. 62 MCI stable). Although the combined ventricular area and volume features did not differ between the two groups, our fine-grained surface analysis revealed significant differences in the ventricular regions close to the temporal lobe and posterior cingulate, structures that are affected early in AD. Significant correlations were also detected between ventricular morphometry, neuropsychological measures, and a previously described imaging index based on fluorodeoxyglucose positron emission tomography (FDG-PET) scans. This novel ventricular morphometry method may offer a new and more sensitive approach to study preclinical and early symptomatic stage AD. PMID:25285374

Color M-mode Doppler flow propagation velocity is a preload insensitive index of left ventricular relaxation: animal and human validation.

PubMed

Garcia, M J; Smedira, N G; Greenberg, N L; Main, M; Firstenberg, M S; Odabashian, J; Thomas, J D

2000-01-01

To determine the effect of preload in color M-mode Doppler flow propagation velocity (v(p)). The interpretation of Doppler filling patterns is limited by confounding effects of left ventricular (LV) relaxation and preload. Color M-mode v(p) has been proposed as a new index of LV relaxation. We studied four dogs before and during inferior caval (IVC) occlusion at five different inotropic stages and 14 patients before and during partial cardiopulmonary bypass. Left ventricular (LV) end-diastolic volumes (LV-EDV), the time constant of isovolumic relaxation (tau), left atrial (LA) pre-A and LV end-diastolic pressures (LV-EDP) were measured. Peak velocity during early filling (E) and v(p) were extracted by digital analysis of color M-mode Doppler images. In both animals and humans, LV-EDV and LV-EDP decreased significantly from baseline to IVC occlusion (both p < 0.001). Peak early filling (E) velocity decreased in animals from 56 +/- 21 to 42 +/- 17 cm/s (p < 0.001) without change in v(p) (from 35 +/- 15 to 35 +/- 16, p = 0.99). Results were similar in humans (from 69 +/- 15 to 53 +/- 22 cm/s, p < 0.001, and 37 +/- 12 to 34 +/- 16, p = 0.30). In both species, there was a strong correlation between LV relaxation (tau) and v(p) (r = 0.78, p < 0.001, r = 0.86, p < 0.001). Our results indicate that color M-mode Doppler v(p) is not affected by preload alterations and confirms that LV relaxation is its main physiologic determinant in both animals during varying lusitropic conditions and in humans with heart disease.

Vagus nerve stimulation mitigates intrinsic cardiac neuronal remodeling and cardiac hypertrophy induced by chronic pressure overload in guinea pig

PubMed Central

Beaumont, Eric; Wright, Gary L.; Southerland, Elizabeth M.; Li, Ying; Chui, Ray; KenKnight, Bruce H.; Armour, J. Andrew

2016-01-01

Our objective was to determine whether chronic vagus nerve stimulation (VNS) mitigates pressure overload (PO)-induced remodeling of the cardioneural interface. Guinea pigs (n = 48) were randomized to right or left cervical vagus (RCV or LCV) implant. After 2 wk, chronic left ventricular PO was induced by partial (15–20%) aortic constriction. Of the 31 animals surviving PO induction, 10 were randomized to RCV VNS, 9 to LCV VNS, and 12 to sham VNS. VNS was delivered at 20 Hz and 1.14 ± 0.03 mA at a 22% duty cycle. VNS commenced 10 days after PO induction and was maintained for 40 days. Time-matched controls (n = 9) were evaluated concurrently. Echocardiograms were obtained before and 50 days after PO. At termination, intracellular current-clamp recordings of intrinsic cardiac (IC) neurons were studied in vitro to determine effects of therapy on soma characteristics. Ventricular cardiomyocyte sizes were assessed with histology along with immunoblot analysis of selected proteins in myocardial tissue extracts. In sham-treated animals, PO increased cardiac output (34%, P < 0.004), as well as systolic (114%, P < 0.04) and diastolic (49%, P < 0.002) left ventricular volumes, a hemodynamic response prevented by VNS. PO-induced enhancements of IC synaptic efficacy and muscarinic sensitivity of IC neurons were mitigated by chronic VNS. Increased myocyte size, which doubled in PO (P < 0.05), was mitigated by RCV. PO hypertrophic myocardium displayed decreased glycogen synthase (GS) protein levels and accumulation of the phosphorylated (inactive) form of GS. These PO-induced changes in GS were moderated by left VNS. Chronic VNS targets IC neurons accompanying PO to obtund associated adverse cardiomyocyte remodeling. PMID:26993230

Vagus nerve stimulation mitigates intrinsic cardiac neuronal remodeling and cardiac hypertrophy induced by chronic pressure overload in guinea pig.

PubMed

Beaumont, Eric; Wright, Gary L; Southerland, Elizabeth M; Li, Ying; Chui, Ray; KenKnight, Bruce H; Armour, J Andrew; Ardell, Jeffrey L

2016-05-15

Our objective was to determine whether chronic vagus nerve stimulation (VNS) mitigates pressure overload (PO)-induced remodeling of the cardioneural interface. Guinea pigs (n = 48) were randomized to right or left cervical vagus (RCV or LCV) implant. After 2 wk, chronic left ventricular PO was induced by partial (15-20%) aortic constriction. Of the 31 animals surviving PO induction, 10 were randomized to RCV VNS, 9 to LCV VNS, and 12 to sham VNS. VNS was delivered at 20 Hz and 1.14 ± 0.03 mA at a 22% duty cycle. VNS commenced 10 days after PO induction and was maintained for 40 days. Time-matched controls (n = 9) were evaluated concurrently. Echocardiograms were obtained before and 50 days after PO. At termination, intracellular current-clamp recordings of intrinsic cardiac (IC) neurons were studied in vitro to determine effects of therapy on soma characteristics. Ventricular cardiomyocyte sizes were assessed with histology along with immunoblot analysis of selected proteins in myocardial tissue extracts. In sham-treated animals, PO increased cardiac output (34%, P < 0.004), as well as systolic (114%, P < 0.04) and diastolic (49%, P < 0.002) left ventricular volumes, a hemodynamic response prevented by VNS. PO-induced enhancements of IC synaptic efficacy and muscarinic sensitivity of IC neurons were mitigated by chronic VNS. Increased myocyte size, which doubled in PO (P < 0.05), was mitigated by RCV. PO hypertrophic myocardium displayed decreased glycogen synthase (GS) protein levels and accumulation of the phosphorylated (inactive) form of GS. These PO-induced changes in GS were moderated by left VNS. Chronic VNS targets IC neurons accompanying PO to obtund associated adverse cardiomyocyte remodeling. Copyright © 2016 the American Physiological Society.

Quinapril decreases myocardial accumulation of extracellular matrix components in spontaneously hypertensive rats.

PubMed

Panizo, A; Pardo, J; Hernández, M; Galindo, M F; Cenarruzabeitia, E; Díez, J

1995-08-01

In genetic and acquired hypertension, a structural remodeling of the nonmyocyte compartment of myocardium, including the accumulation of fibrillar collagen and other components of the extracellular matrix (ECM) within the interstitium, represents a determinant of pathologic hypertrophy that leads to ventricular dysfunction. Therefore, to evaluate the potential benefit of the angiotensin converting enzyme (ACE) inhibitor quinapril in reversing the interstitial remodeling in spontaneously hypertensive rats (SHR) with established left ventricular hypertrophy (LVH), we treated 16-week-old male SHR with oral quinapril (average dose, 10 mg/kg body weight/day) for 20 weeks. Interstitial fibrosis was determined morphometrically using an automatic image analyzer. The amount of collagen was evaluated by measuring myocardial hydroxyproline concentration. Myocardial deposition of collagen molecules (types I, III, and IV) and other ECM components (fibronectin, laminin) was analyzed by immunohistochemical techniques using specific monoclonal antibodies. The activity of ACE was measured in left ventricular tissue by a fluorometric assay. In quinapril-treated SHR compared with 36-week-old untreated SHR and age- and sex-matched Wistar-Kyoto (WKY) controls, we found 1) a lesser degree of LVH and a lesser level of blood pressure, 2) a lesser degree of interstitial fibrosis, represented by less interstitial collagen volume fraction (5.73 +/- 0.45% v 3.42 +/- 0.28%, P < .05; WKY, 3.44 +/- 0.66%), 3) a lower hydroxyproline concentration (1.09 +/- 0.05 mumol/L/g dry weight/100 g body weight to 0.81 +/- 0.05 mumol/L/g dry weight/100 g body weight, P < .05; WKY, 0.96 +/- 0.06 mumol/L/g dry weight/100 g body weight), 4) a lesser presence of collagen fibers, and 5) a lesser presence of collagen IV, fibronectin, and laminin.(ABSTRACT TRUNCATED AT 250 WORDS)

Color M-mode Doppler flow propagation velocity is a preload insensitive index of left ventricular relaxation: animal and human validation

NASA Technical Reports Server (NTRS)

Garcia, M. J.; Smedira, N. G.; Greenberg, N. L.; Main, M.; Firstenberg, M. S.; Odabashian, J.; Thomas, J. D.

2000-01-01

OBJECTIVES: To determine the effect of preload in color M-mode Doppler flow propagation velocity (v(p)). BACKGROUND: The interpretation of Doppler filling patterns is limited by confounding effects of left ventricular (LV) relaxation and preload. Color M-mode v(p) has been proposed as a new index of LV relaxation. METHODS: We studied four dogs before and during inferior caval (IVC) occlusion at five different inotropic stages and 14 patients before and during partial cardiopulmonary bypass. Left ventricular (LV) end-diastolic volumes (LV-EDV), the time constant of isovolumic relaxation (tau), left atrial (LA) pre-A and LV end-diastolic pressures (LV-EDP) were measured. Peak velocity during early filling (E) and v(p) were extracted by digital analysis of color M-mode Doppler images. RESULTS: In both animals and humans, LV-EDV and LV-EDP decreased significantly from baseline to IVC occlusion (both p < 0.001). Peak early filling (E) velocity decreased in animals from 56 +/- 21 to 42 +/- 17 cm/s (p < 0.001) without change in v(p) (from 35 +/- 15 to 35 +/- 16, p = 0.99). Results were similar in humans (from 69 +/- 15 to 53 +/- 22 cm/s, p < 0.001, and 37 +/- 12 to 34 +/- 16, p = 0.30). In both species, there was a strong correlation between LV relaxation (tau) and v(p) (r = 0.78, p < 0.001, r = 0.86, p < 0.001). CONCLUSIONS: Our results indicate that color M-mode Doppler v(p) is not affected by preload alterations and confirms that LV relaxation is its main physiologic determinant in both animals during varying lusitropic conditions and in humans with heart disease.

Comparison of gating methods for the real-time analysis of left ventricular function in nonimaging blood pool studies.

PubMed

Beard, B B; Stewart, J R; Shiavi, R G; Lorenz, C H

1995-01-01

Gating methods developed for electrocardiographic-triggered radionuclide ventriculography are being used with nonimaging detectors. These methods have not been compared on the basis of their real-time performance or suitability for determination of load-independent indexes of left ventricular function. This work evaluated the relative merits of different gating methods for nonimaging radionuclude ventriculographic studies, with particular emphasis on their suitability for real-time measurements and the determination of pressure-volume loops. A computer model was used to investigate the relative accuracy of forward gating, backward gating, and phase-mode gating. The durations of simulated left ventricular time-activity curves were randomly varied. Three acquisition parameters were considered: frame rate, acceptance window, and sample size. Twenty-five studies were performed for each combination of acquisition parameters. Hemodynamic and shape parameters from each study were compared with reference parameters derived directly from the random time-activity curves. Backward gating produced the largest errors under all conditions. For both forward gating and phase-mode gating, ejection fraction was underestimated and time to end systole and normalized peak ejection rate were overestimated. For the hemodynamic parameters, forward gating was marginally superior to phase-mode gating. The mean difference in errors between forward and phase-mode gating was 1.47% (SD 2.78%). However, for root mean square shape error, forward gating was several times worse in every case and seven times worse than phase-mode gating on average. Both forward and phase-mode gating are suitable for real-time hemodynamic measurements by nonimaging techniques. The small statistical difference between the methods is not clinically significant. The true shape of the time-activity curve is maintained most accurately by phase-mode gating.

Comparison of gating methods for the real-time analysis of left ventricular function in nonimaging blood pool studies

PubMed Central

Beard, Brian B.; Stewart, James R.; Shiavi, Richard G.; Lorenz, Christine H.

2018-01-01

Background Gating methods developed for electrocardiographic-triggered radionuclide ventriculography are being used with nonimaging detectors. These methods have not been compared on the basis of their real-time performance or suitability for determination of load-independent indexes of left ventricular function. This work evaluated the relative merits of different gating methods for nonimaging radionuclude ventriculographic studies, with particular emphasis on their suitability for real-time measurements and the determination of pressure-volume loops. Methods and Results A computer model was used to investigate the relative accuracy of forward gating, backward gating, and phase-mode gating. The durations of simulated left ventricular time-activity curves were randomly varied. Three acquisition parameters were considered: frame rate, acceptance window, and sample size. Twenty-five studies were performed for each combination of acquisition parameters. Hemodynamic and shape parameters from each study were compared with reference parameters derived directly from the random time-activity curves. Backward gating produced the largest errors under all conditions. For both forward gating and phase-mode gating, ejection fraction was underestimated and time to end systole and normalized peak ejection rate were overestimated. For the hemodynamic parameters, forward gating was marginally superior to phase-mode gating. The mean difference in errors between forward and phase-mode gating was 1.47% (SD 2.78%). However, for root mean square shape error, forward gating was several times worse in every case and seven times worse than phase-mode gating on average. Conclusions Both forward and phase-mode gating are suitable for real-time hemodynamic measurements by nonimaging techniques. The small statistical difference between the methods is not clinically significant. The true shape of the time-activity curve is maintained most accurately by phase-mode gating. PMID:9420820

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.

Anesthesia in a Combat Environment

DTIC Science & Technology

1981-09-25

infusion in those patients where disruption of iliac vei~ns or inferior vena cava is a possibility (pelvic, abdominal, or chest trauima), A cathetor...minimal or no decrease in cardiac output, stroke volume, left -ventricular work, stroke work, and mean arterial pressure (5). Halothane, fluroxene, and...healthy young male volunteers to preserve cardiac output unchanged, decrease stroke volume, arterial pressure, peripheral resistance, 02 and left

Features of Brain MRI in Dogs with Treated and Untreated Mucopolysaccharidosis Type I

PubMed Central

Vite, Charles H; Nestrasil, Igor; Mlikotic, Anton; Jens, Jackie K; Snella, Elizabeth M; Gross, William; Shapiro, Elsa G; Kovac, Victor; Provenzale, James M; Chen, Steven; Le, Steven Q; Kan, Shih-hsin; Banakar, Shida; Wang, Raymond Y; Haskins, Mark E; Ellinwood, N Matthew; Dickson, Patricia I

2013-01-01

The mucopolysaccharidosis type I (MPS I) dog model has been important in the development of therapies for human patients. We treated dogs with enzyme replacement therapy (ERT) by various approaches. Dogs assessed included untreated MPS I dogs, heterozygous carrier dogs, and MPS I dogs treated with intravenous ERT as adults (beginning at age 13 to 16 mo), intrathecal and intravenous ERT as adults (beginning at age 13 to 16 mo), or intrathecal ERT as juveniles (beginning at age 4 mo). We then characterized the neuroimaging findings of 32 of these dogs (age, 12 to 30 mo). Whole and midsagittal volumes of the corpus callosum, measured from brain MRI, were significantly smaller in affected dogs compared with unaffected heterozygotes. Corpus callosum volumes in dogs that were treated with intrathecal ERT from 4 mo until 21 mo of age were indistinguishable from those of age-matched carrier controls. Dogs with MPS I showed cerebral ventricular enlargement and cortical atrophy as early as 12 mo of age. Ventricular enlargement was greater in untreated MPS I dogs than in age-matched dogs treated with intrathecal ERT as juveniles or adults. However, treated dogs still showed some ventricular enlargement or cortical atrophy (or both). Understanding the progression of neuroimaging findings in dogs with MPS I and their response to brain-directed therapy may improve preclinical studies for new human-directed therapies. In particular, corpus callosum volumes may be useful quantitative neuroimaging markers for MPS-related brain disease and its response to therapy. PMID:23582423

Non‐invasive evaluation of the myocardial substrate of cardiac amyloidosis by gadolinium cardiac magnetic resonance

PubMed Central

Perugini, E; Rapezzi, C; Piva, T; Leone, O; Bacchi‐Reggiani, L; Riva, L; Salvi, F; Lovato, L; Branzi, A; Fattori, R

2006-01-01

Objective To investigate the prevalence and distribution of gadolinium (Gd) enhancement at cardiac magnetic resonance (CMR) imaging in patients with cardiac amyloidosis (CA) and to look for associations with clinical, morphological, and functional features. Patients and design 21 patients with definitely diagnosed CA (nine with immunoglobulin light chain amyloidosis and 12 transthyretin related) underwent Gd‐CMR. Results Gd enhancement was detected in 16 of 21 (76%) patients. Sixty six of 357 (18%) segments were enhanced, more often at the mid ventricular level. Transmural extension of enhancement within each patient significantly correlated with left ventricular (LV) end systolic volume (r  =  0.58). The number of enhanced segments correlated with LV end diastolic volume (r  =  0.76), end systolic volume (r  =  0.6), and left atrial size (r  =  0.56). Segments with > 50% extensive transmural enhancement more often were severely hypokinetic or akinetic (p  =  0.001). Patients with > 2 enhanced segments had significantly lower 12 lead QRS voltage and Sokolow‐Lyon index. No relation was apparent with any other clinical, morphological, functional, or histological characteristics. Conclusion Gd enhancement is common but not universally present in CA, probably due to expansion of infiltrated interstitium. The segmental and transmural distribution of the enhancement is highly variable, and mid‐ventricular regions are more often involved. Enhancement appears to be associated with impaired segmental and global contractility and a larger atrium. PMID:15939726

Noninvasive quantification of left ventricular mass by cardiac magnetic resonance imaging: Development of the method and experimental validation

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

Maddahi, J.; Crues, J.; Berman, D.S.

1985-05-01

Determination of left ventricular myocardial (LV) mass may aid evaluation of hypertrophic cardiomyopathies as well as percent viable myocardium in ischemic heart disease. The validity of cardiac NMR for determination of LV mass was evaluated in 9 dogs using a superconducting magnet operating at 0.35 Tesla. In-vivo gated spin echo pulsing sequences were used obtaining 0.7 cm thick slices of the heart, spaced by 1 cm, in three orthogonal planes. After sacrifice, the nonbeating hearts were imaged in-situ without gating. On each NMR slice, the LV surface area was planimetered and multiplied by slice spacing (1) and myocardial specific gravitymore » (1.05) to obtain slice mass. For total LV mass, slice masses were added on coronal (Method (Meth) 1), transaxial (Meth 2), and sagittal (Meth 3) planes. Mass of the LV portions subject to partial volume effect were derived from an orthogonal plane. Excised LV weight ranged from 27 to 134 grams. The intra- and inter-observer agreement for planimetry of the NMR slices was high (r=.99 and r=.97, respectively). For in-situ imaging, r values of all methods were high (r=.99, .99, and .98); however, the slope and intercept of the regression line were closes to the line of identity with Meth 1 (y=0.94x+0.52). For in-vivo beating heart images, Meth 1 also had the best results (r=.99, y= 0.99x+8.3). Failure to correct for partial volume effect resulted in underestimation of in-situ and in-vivo LV masses as indicated by slope of <1 (r=,.98, y=0.77x+3.9; r=.98, y= 0.88x+0.98, respectively, Meth 1). Thus, cardiac NMR is a reproducible and accurate method for noninvasive determination of LV myocardial mass.« less

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

Relationship of central and peripheral blood pressure to left ventricular mass in hypertensive patients.

PubMed

Pérez-Lahiguera, Francisco J; Rodilla, Enrique; Costa, Jose A; Gonzalez, Carmen; Martín, Joaquin; Pascual, Jose M

2012-12-01

The purpose of the present study was to assess the relationship of central and peripheral blood pressure to left ventricular mass. Cross-sectional study that included 392 never treated hypertensive individuals. Measurement of office, 24-h ambulatory, and central blood pressure (obtained using applanation tonometry) and determination of left ventricular mass by echocardiography were performed in all patients. In a multiple regression analysis, with adjustment for age, gender and metabolic syndrome, 24-h blood pressure was more closely related to ventricular mass than the respective office and central blood pressures. Systolic blood pressures always exhibited a higher correlation than diastolic blood pressures in all 3 determinations. The correlation between left ventricular mass index and 24-h systolic blood pressure was higher than that of office (P<.002) or central systolic blood pressures (P<.002). Changes in 24-h systolic blood pressure caused the greatest variations in left ventricular mass index (P<.001). In our population of untreated middle-aged hypertensive patients, left ventricular mass index is more closely related to 24-h ambulatory blood pressure than to office or central blood pressure. Central blood pressure does not enable us to better identify patients with left ventricular hypertrophy. Copyright © 2012 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Vernakalant selectively prolongs atrial refractoriness with no effect on ventricular refractoriness or defibrillation threshold in pigs.

PubMed

Bechard, Jeff; Gibson, John Ken; Killingsworth, Cheryl R; Wheeler, Jeffery J; Schneidkraut, Marlowe J; Huang, Jian; Ideker, Raymond E; McAfee, Donald A

2011-03-01

Vernakalant is a novel antiarrhythmic agent that has demonstrated clinical efficacy for the treatment of atrial fibrillation. Vernakalant blocks, to various degrees, cardiac sodium and potassium channels with a pattern that suggests atrial selectivity. We hypothesized, therefore, that vernakalant would affect atrial more than ventricular effective refractory period (ERP) and have little or no effect on ventricular defibrillation threshold (DFT). Atrial and ventricular ERP and ventricular DFT were determined before and after treatment with vernakalant or vehicle in 23 anesthetized male mixed-breed pigs. Vernakalant was infused at a rate designed to achieve stable plasma levels similar to those in human clinical trials. Atrial and ventricular ERP were determined by endocardial extrastimuli delivered to the right atria or right ventricle. Defibrillation was achieved using external biphasic shocks delivered through adhesive defibrillation patches placed on the thorax after 10 seconds of electrically induced ventricular fibrillation. The DFT was estimated using the Dixon "up-and-down" method. Vernakalant significantly increased atrial ERP compared with vehicle controls (34 ± 8 versus 9 ± 7 msec, respectively) without significantly affecting ventricular ERP or DFT. This is consistent with atrial selective actions and supports the conclusion that vernakalant does not alter the efficacy of electrical defibrillation.

Dynamic radionuclide determination of regional left ventricular wall motion using a new digital imaging device

NASA Technical Reports Server (NTRS)

Steele, P.; Kirch, D.

1975-01-01

In 47 men with arteriographically defined coronary artery disease comparative studies of left ventricular ejection fraction and segmental wall motion were made with radionuclide data obtained from the image intensifier camera computer system and with contrast cineventriculography. The radionuclide data was digitized and the images corresponding to left ventricular end-diastole and end-systole were identified from the left ventricular time-activity curve. The left ventricular end-diastolic and end-systolic images were subtracted to form a silhouette difference image which described wall motion of the anterior and inferior left ventricular segments. The image intensifier camera allows manipulation of dynamically acquired radionuclide data because of the high count rate and consequently improved resolution of the left ventricular image.

Does load-induced ventricular hypertrophy progress to systolic heart failure?

PubMed

Berenji, Kambeez; Drazner, Mark H; Rothermel, Beverly A; Hill, Joseph A

2005-07-01

Ventricular hypertrophy develops in response to numerous forms of cardiac stress, including pressure or volume overload, loss of contractile mass from prior infarction, neuroendocrine activation, and mutations in genes encoding sarcomeric proteins. Hypertrophic growth is believed to have a compensatory role that diminishes wall stress and oxygen consumption, but Framingham and other studies established ventricular hypertrophy as a marker for increased risk of developing chronic heart failure, suggesting that hypertrophy may have maladaptive features. However, the relative contribution of comorbid disease to hypertrophy-associated systolic failure is unknown. For instance, coronary artery disease is induced by many of the same risk factors that cause hypertrophy and can itself lead to systolic dysfunction. It is uncertain, therefore, whether ventricular hypertrophy commonly progresses to systolic dysfunction without the contribution of intervening ischemia or infarction. In this review, we summarize findings from epidemiologic studies, preclinical experiments in animals, and clinical trials to lay out what is known-and not known-about this important question.

Impact of left atrial volume reduction concomitant with atrial fibrillation surgery on left atrial geometry and mechanical function.

PubMed

Marui, Akira; Saji, Yoshiaki; Nishina, Takeshi; Tadamura, Eiji; Kanao, Shotaro; Shimamoto, Takeshi; Sasahashi, Nozomu; Ikeda, Tadashi; Komeda, Masashi

2008-06-01

Left atrial geometry and mechanical functions exert a profound effect on left ventricular filling and overall cardiovascular performance. We sought to investigate the perioperative factors that influence left atrial geometry and mechanical functions after the Maze procedure in patients with refractory atrial fibrillation and left atrial enlargement. Seventy-four patients with atrial fibrillation and left atrial enlargement (diameter > or = 60 mm) underwent the Maze procedure in association with mitral valve surgery. The maximum left atrial volume and left atrial mechanical functions (booster pump, reservoir, and conduit function [%]) were calculated from the left atrial volume-cardiac cycle curves obtained by magnetic resonance imaging. A stepwise multiple regression analysis was performed to determine the independent variables that influenced the postoperative left atrial geometry and function. The multivariate analysis showed that left atrial reduction surgery concomitant with the Maze procedure and the postoperative maintenance of sinus rhythm were predominant independent variables for postoperative left atrial geometry and mechanical functions. Among the 58 patients who recovered sinus rhythm, the postoperative left atrial geometry and function were compared between patients with (VR group) and without (control group) left atrial volume reduction. At a mean follow-up period of 13.8 months, sinus rhythm recovery rate was better (85% vs 68%, P < .05) in the VR group and maximum left atrial volume was less (116 +/- 25 mL vs 287 +/- 73 mL, P < .001) than in the control group. The maximum left atrial volume reduced with time only in the VR group (reverse remodeling). Postoperative booster pump and reservoir function in the VR group were better than in the control group (25% +/- 6% vs 11% +/- 4% and 34% +/- 7% vs 16% +/- 4%, respectively, P < .001), whereas the conduit function in the VR group was lower than in the control group, indicating that the improvement of the booster pump and reservoir function compensated for the conduit function to left ventricular filling. Left atrial reduction concomitant with the Maze procedure helped restore both contraction (booster pump) and compliance (reservoir) of the left atrium and facilitated left atrial reverse remolding. Left atrial volume reduction and postoperative maintenance of sinus rhythm may be desirable in patients with refractory AF and left atrial enlargement.

Post-hypothermic cardiac left ventricular systolic dysfunction after rewarming in an intact pig model

PubMed Central

2010-01-01

Introduction We developed a minimally invasive, closed chest pig model with the main aim to describe hemodynamic function during surface cooling, steady state severe hypothermia (one hour at 25°C) and surface rewarming. Methods Twelve anesthetized juvenile pigs were acutely catheterized for measurement of left ventricular (LV) pressure-volume loops (conductance catheter), cardiac output (Swan-Ganz), and for vena cava inferior occlusion. Eight animals were surface cooled to 25°C, while four animals were kept as normothermic time-matched controls. Results During progressive cooling and steady state severe hypothermia (25°C) cardiac output (CO), stroke volume (SV), mean arterial pressure (MAP), maximal deceleration of pressure in the cardiac cycle (dP/dtmin), indexes of LV contractility (preload recruitable stroke work, PRSW, and maximal acceleration of pressure in the cardiac cycle, dP/dtmax) and LV end diastolic and systolic volumes (EDV and ESV) were significantly reduced. Systemic vascular resistance (SVR), isovolumetric relaxation time (Tau), and oxygen content in arterial and mixed venous blood increased significantly. LV end diastolic pressure (EDP) remained constant. After rewarming all the above mentioned hemodynamic variables that were depressed during 25°C remained reduced, except for CO that returned to pre-hypothermic values due to an increase in heart rate. Likewise, SVR and EDP were significantly reduced after rewarming, while Tau, EDV, ESV and blood oxygen content normalized. Serum levels of cardiac troponin T (TnT) and tumor necrosis factor-alpha (TNF-α) were significantly increased. Conclusions Progressive cooling to 25°C followed by rewarming resulted in a reduced systolic, but not diastolic left ventricular function. The post-hypothermic increase in heart rate and the reduced systemic vascular resistance are interpreted as adaptive measures by the organism to compensate for a hypothermia-induced mild left ventricular cardiac failure. A post-hypothermic increase in TnT indicates that hypothermia/rewarming may cause degradation of cardiac tissue. There were no signs of inadequate global oxygenation throughout the experiments. PMID:21092272

Oxygen-saving effect of a new cardiotonic agent, MCI-154, in diseased human hearts.

PubMed

Mori, M; Takeuchi, M; Takaoka, H; Hata, K; Hayashi, Y; Yamakawa, H; Yokoyama, M

1997-03-01

The aim of this study was to examine the left ventricular mechanoenergetic effects of a novel Ca2+ sensitizing agent, MCI-154, on diseased human hearts compared with dobutamine. Unlike conventional cardiotonic agents, a Ca2+ sensitizer that could produce a positive inotropic action by altering the responsiveness of myofilament to Ca2+ could generate force with smaller amounts of Ca2+; thus, it may potentially save energy expenditure. The left ventricular pressure-volume relation and myocardial oxygen consumption per beat (Vo2) were measured by a conductance (volume) catheter and a Webster catheter. Left ventricular contractility (Emax), systolic pressure-volume area (PVA [index of left ventricular total mechanical energy]) and Vo2 were assessed before and after infusion of MCI-154 or dobut-amine. The PVA-independent Vo2 (Vo2 mainly for excitation-contraction coupling) was assessed as the Vo2 at zero PVA. Both agents increased Emax comparably (dobutamine: from 3.55 +/- 1.10 [mean +/- SD] to 5.04 +/- 1.16 mm Hg/ml per m2, p < 0.0001; MCI-154: from 3.36 +/- 1.26 to 5.37 +/- 2.14 mm Hg/ml per m2, p < 0.0001); dobutamine increased total Vo2 (from 0.22 +/- 0.08 to 0.27 +/- 0.09 ml O2, p < 0.05) and PVA-independent Vo2 (from 0.019 +/- 0.019 to 0.091 +/- 0.051 ml O2, p < 0.005); but MCI-154 did not change these variables significantly. Consequently, the oxygen cost of contractility (delta PVA-independent Vo2/delta Emax) was less with MCI-154 than with dobutamine (0.14 +/- 0.18 vs. 1.10 +/- 0.80 J/mm Hg per ml per m2, p < 0.05). These results suggest that the cardiotonic action mediated by MCI-154 could provide an energetic advantage over the conventional cardiotonic action with currently used inotropic agents.

A single strain-based growth law predicts concentric and eccentric cardiac growth during pressure and volume overload

PubMed Central

Kerckhoffs, Roy C.P.; Omens, Jeffrey; McCulloch, Andrew D.

2011-01-01

Adult cardiac muscle adapts to mechanical changes in the environment by growth and remodeling (G&R) via a variety of mechanisms. Hypertrophy develops when the heart is subjected to chronic mechanical overload. In ventricular pressure overload (e.g. due to aortic stenosis) the heart typically reacts by concentric hypertrophic growth, characterized by wall thickening due to myocyte radial growth when sarcomeres are added in parallel. In ventricular volume overload, an increase in filling pressure (e.g. due to mitral regurgitation) leads to eccentric hypertrophy as myocytes grow axially by adding sarcomeres in series leading to ventricular cavity enlargement that is typically accompanied by some wall thickening. The specific biomechanical stimuli that stimulate different modes of ventricular hypertrophy are still poorly understood. In a recent study, based on in-vitro studies in micropatterned myocyte cell cultures subjected to stretch, we proposed that cardiac myocytes grow longer to maintain a preferred sarcomere length in response to increased fiber strain and grow thicker to maintain interfilament lattice spacing in response to increased cross-fiber strain. Here, we test whether this growth law is able to predict concentric and eccentric hypertrophy in response to aortic stenosis and mitral valve regurgitation, respectively, in a computational model of the adult canine heart coupled to a closed loop model of circulatory hemodynamics. A non-linear finite element model of the beating canine ventricles coupled to the circulation was used. After inducing valve alterations, the ventricles were allowed to adapt in shape in response to mechanical stimuli over time. The proposed growth law was able to reproduce major acute and chronic physiological responses (structural and functional) when integrated with comprehensive models of the pressure-overloaded and volume-overloaded canine heart, coupled to a closed-loop circulation. We conclude that strain-based biomechanical stimuli can drive cardiac growth, including wall thickening during pressure overload. PMID:22639476

Evaluation of Cardiovascular Risk Factors in the Wistar Audiogenic Rat (WAR) Strain

PubMed Central

Fazan, Rubens; Silva, Carlos Alberto A.; Oliveira, José Antônio Cortes; Salgado, Helio Cesar; Montano, Nicola; Garcia-Cairasco, Norberto

2015-01-01

Introduction Risk factors for life-threatening cardiovascular events were evaluated in an experimental model of epilepsy, the Wistar Audiogenic Rat (WAR) strain. Methods We used long-term ECG recordings in conscious, one year old, WAR and Wistar control counterparts to evaluate spontaneous arrhythmias and heart rate variability, a tool to assess autonomic cardiac control. Ventricular function was also evaluated using the pressure-volume conductance system in anesthetized rats. Results Basal RR interval (RRi) was similar between WAR and Wistar rats (188±5 vs 199±6 ms). RRi variability strongly suggests that WAR present an autonomic imbalance with sympathetic overactivity, which is an isolated risk factor for cardiovascular events. Anesthetized WAR showed lower arterial pressure (92±3 vs 115±5 mmHg) and exhibited indices of systolic dysfunction, such as higher ventricle end-diastolic pressure (9.2±0.6 vs 5.6±1 mmHg) and volume (137±9 vs 68±9 μL) as well as lower rate of increase in ventricular pressure (5266±602 vs 7320±538 mmHg.s-1). Indices of diastolic cardiac function, such as lower rate of decrease in ventricular pressure (-5014±780 vs -7766±998 mmHg.s-1) and a higher slope of the linear relationship between end-diastolic pressure and volume (0.078±0.011 vs 0.036±0.011 mmHg.μL), were also found in WAR as compared to Wistar control rats. Moreover, Wistar rats had 3 to 6 ventricular ectopic beats, whereas WAR showed 15 to 30 ectopic beats out of the 20,000 beats analyzed in each rat. Conclusions The autonomic imbalance observed previously at younger age is also present in aged WAR and, additionally, a cardiac dysfunction was also observed in the rats. These findings make this experimental model of epilepsy a valuable tool to study risk factors for cardiovascular events in epilepsy. PMID:26029918

Two-dimensional knowledge-based volumetric reconstruction of the right ventricle documents short-term improvement in pulmonary hypertension.

PubMed

Schwaiger, Johannes P; Knight, Daniel S; Kaier, Thomas; Gallimore, Adele; Denton, Christopher P; Schreiber, Benjamin E; Handler, Clive; Coghlan, John G

2017-06-01

Data are scarce about short-term right ventricular changes in pulmonary hypertension. Two-dimensional knowledge-based reconstruction of the right ventricle with 2D echocardiography (2DKBR) has been shown to be a valid alternative to Cardiac MRI. In this longitudinal study 25 pulmonary hypertension patients underwent 2DKBR of the right ventricle, assessment of NT-proBNP levels and functional class at baseline and after a mean follow-up of 6.1 months. Patients were followed up clinically for a further mean of 8.2 months. The majority of patients had connective tissue disease (CTD) associated pulmonary arterial hypertension (n=15) or chronic thromboembolic pulmonary hypertension (CTEPH; n=6). A total of 15 patients underwent an intervention, either new targeted therapy, escalation of targeted therapy or pulmonary endarterectomy. A total of 10 clinically stable patients were routinely followed up without any change in therapy. There were significant improvements in the right ventricular end-diastolic volume index (111±29 mL/m² vs 100±36 mL/m²; P=.038), end-systolic volume index (72±23 mL/m² vs 61±25 mL/m²; P=.001), and ejection fraction (35±10% vs 40±9%; P=.030). Changes in NT-proBNP levels correlated strongest with changes in end-systolic volume index (r=-.77; P=<.0001). Four patients experienced clinical worsening during extended follow-up, dilatation of the right ventricle was associated with clinical worsening. In a CTD and CTEPH dominated patient population significant reverse remodeling and improvement of ejection fraction occurred despite a short follow-up and was paralleled by significant changes in NT-proBNP levels. Further right ventricular dilatation was associated with worse clinical outcome. 2DKBR is a feasible substitute for Cardiac MRI to follow-up right ventricular indices in pulmonary hypertension. © 2017, Wiley Periodicals, Inc.

Diffuse Myocardial Fibrosis Reduces Electrocardiographic Voltage Measures of Left Ventricular Hypertrophy Independent of Left Ventricular Mass.

PubMed

Maanja, Maren; Wieslander, Björn; Schlegel, Todd T; Bacharova, Ljuba; Abu Daya, Hussein; Fridman, Yaron; Wong, Timothy C; Schelbert, Erik B; Ugander, Martin

2017-01-22

Myocardial fibrosis quantified by myocardial extracellular volume fraction (ECV) and left ventricular mass (LVM) index (LVMI) measured by cardiovascular magnetic resonance might represent independent and opposing contributors to ECG voltage measures of left ventricular hypertrophy (LVH). Diffuse myocardial fibrosis can occur in LVH and interfere with ECG voltage measures. This phenomenon could explain the decreased sensitivity of LVH detectable by ECG, a fundamental diagnostic tool in cardiology. We identified 77 patients (median age, 53 [interquartile range, 26-60] years; 49% female) referred for contrast-enhanced cardiovascular magnetic resonance with ECV measures and 12-lead ECG. Exclusion criteria included clinical confounders that might influence ECG measures of LVH. We evaluated ECG voltage-based LVH measures, including Sokolow-Lyon index, Cornell voltage, 12-lead voltage, and the vectorcardiogram spatial QRS voltage, with respect to LVMI and ECV. ECV and LVMI were not correlated (R 2 =0.02; P=0.25). For all voltage-related parameters, higher LVMI resulted in greater voltage (r=0.33-0.49; P<0.05 for all), whereas increased ECV resulted in lower voltage (r=-0.32 to -0.57; P<0.05 for all). When accounting for body fat, LV end-diastolic volume, and mass-to-volume ratio, both LVMI (β=0.58, P=0.03) and ECV (β=-0.46, P<0.001) were independent predictors of QRS voltage (multivariate adjusted R 2 =0.39; P<0.001). Myocardial mass and diffuse myocardial fibrosis have independent and opposing effects upon ECG voltage measures of LVH. Diffuse myocardial fibrosis quantified by ECV can obscure the ECG manifestations of increased LVM. This provides mechanistic insight, which can explain the limited sensitivity of the ECG for detecting increased LVM. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Predictors of Sudden Cardiac Death in Doberman Pinschers with Dilated Cardiomyopathy.

PubMed

Klüser, L; Holler, P J; Simak, J; Tater, G; Smets, P; Rügamer, D; Küchenhoff, H; Wess, G

2016-05-01

Doberman Pinschers with dilated cardiomyopathy (DCM) are at high risk of sudden cardiac death (SCD). Risk factors for SCD are poorly defined. To assess cardiac biomarkers, Holter-ECG, echocardiographic variables and canine characteristics in a group of Doberman Pinschers with DCM dying of SCD and in a DCM control group to identify factors predicting SCD. A longitudinal prospective study was performed in 95 Doberman Pinschers with DCM. Forty-one dogs died within 3 months after the last cardiac examination (SCD-group) and were compared to 54 Doberman Pinschers with DCM surviving 1 year after inclusion. Holter-ECG, echocardiography, measurement of N-terminal prohormone of brain-natriuretic peptide (NT-proBNP), and cardiac Troponin I (cTnI) concentrations were recorded for all dogs. Volume overload of the left ventricle (left ventricular end-diastolic volume (LVEDV/BSA) > 91.3 mL/m²) was the single best variable to predict SCD. The probability of SCD increases 8.5-fold (CI0.95  = 0.8-35.3) for every 50 mL/m²-unit increment in LVEDV/BSA. Ejection fraction (EF), left ventricular end-systolic volume (LVESV/BSA) and NT-proBNP were highly correlated with LVEDV/BSA (r = -0.63, 0.96, 0.86, respectively). Generated conditional inference trees (CTREEs) revealed that the presence of ventricular tachycardia (VT), increased concentration of cTnI, and the fastest rate (FR) of ventricular premature complexes (VPC) ≥260 beats per minute (bpm) are additional important variables to predict SCD. Conditional inference trees provided in this study might be useful for risk assessment of SCD in Doberman Pinschers with DCM. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Progression of Hypertrophy and Myocardial Fibrosis in Aortic Stenosis: A Multicenter Cardiac Magnetic Resonance Study.

PubMed

Everett, Russell J; Tastet, Lionel; Clavel, Marie-Annick; Chin, Calvin W L; Capoulade, Romain; Vassiliou, Vassilios S; Kwiecinski, Jacek; Gomez, Miquel; van Beek, Edwin J R; White, Audrey C; Prasad, Sanjay K; Larose, Eric; Tuck, Christopher; Semple, Scott; Newby, David E; Pibarot, Philippe; Dweck, Marc R

2018-06-01

Aortic stenosis is accompanied by progressive left ventricular hypertrophy and fibrosis. We investigated the natural history of these processes in asymptomatic patients and their potential reversal post-aortic valve replacement (AVR). Asymptomatic and symptomatic patients with aortic stenosis underwent repeat echocardiography and magnetic resonance imaging. Changes in peak aortic-jet velocity, left ventricular mass index, diffuse fibrosis (indexed extracellular volume), and replacement fibrosis (late gadolinium enhancement [LGE]) were quantified. In 61 asymptomatic patients (43% mild, 34% moderate, and 23% severe aortic stenosis), significant increases in peak aortic-jet velocity, left ventricular mass index, indexed extracellular volume, and LGE mass were observed after 2.1±0.7 years, with the most rapid progression observed in patients with most severe stenosis. Patients with baseline midwall LGE (n=16 [26%]; LGE mass, 2.5 g [0.8-4.8 g]) demonstrated particularly rapid increases in scar burden (78% [50%-158%] increase in LGE mass per year). In 38 symptomatic patients (age, 66±8 years; 76% men) who underwent AVR, there was a 19% (11%-25%) reduction in left ventricular mass index ( P <0.0001) and an 11% (4%-16%) reduction in indexed extracellular volume ( P =0.003) 0.9±0.3 years after surgery. By contrast midwall LGE (n=10 [26%]; mass, 3.3 g [2.6-8.0 g]) did not change post-AVR (n=10; 3.5 g [2.1-8.0 g]; P =0.23), with no evidence of regression even out to 2 years. In patients with aortic stenosis, cellular hypertrophy and diffuse fibrosis progress in a rapid and balanced manner but are reversible after AVR. Once established, midwall LGE also accumulates rapidly but is irreversible post valve replacement. Given its adverse long-term prognosis, prompt AVR when midwall LGE is first identified may improve clinical outcomes. URL: https://www.clinicaltrials.gov. Unique identifiers: NCT01755936 and NCT01679431. © 2018 The Authors.

Spontaneous haemorrhage and rupture of third ventricular colloid cyst

PubMed Central

Ogbodo, Elisha; Kaliaperumal, Chandrasekaran; Bermingham, Niamh; O'Sullivan, Michael

2012-01-01

Acute bleeding within a colloid cyst of the third ventricle represents a rare event causing sudden increase in the cyst volume that may lead to acute hydrocephalus and rapid neurological deterioration. We report a case of spontaneous rupture of haemorrhagic third ventricular colloid cyst and its management. A 77-year-old ex-smoker presented with unsteady gait, incontinence and gradually worsening confusion over a 3-week period. Brain CT scan findings were highly suggestive of a third ventricular colloid cyst with intraventricular rupture. He underwent cyst excision and histopathology, which confirmed the radiological diagnosis with evidence of haemorrhage within the cyst. A ventriculo peritoneal shunt was performed for delayed hydrocephalus. Surgical management of these patients must include emergency ventriculostomy followed by prompt surgical removal of the haemorrhagic cyst. PMID:22949002

Matrix-array 3-dimensional echocardiographic assessment of volumes, mass, and ejection fraction in young pediatric patients with a functional single ventricle: a comparison study with cardiac magnetic resonance.

PubMed

Soriano, Brian D; Hoch, Martin; Ithuralde, Alejandro; Geva, Tal; Powell, Andrew J; Kussman, Barry D; Graham, Dionne A; Tworetzky, Wayne; Marx, Gerald R

2008-04-08

Quantitative assessment of ventricular volumes and mass in pediatric patients with single-ventricle physiology would aid clinical management, but it is difficult to obtain with 2-dimensional echocardiography. The purpose of the present study was to compare matrix-array 3-dimensional echocardiography (3DE) measurements of single-ventricle volumes, mass, and ejection fraction with those measured by cardiac magnetic resonance (CMR) in young patients. Twenty-nine patients (median age, 7 months) with a functional single ventricle undergoing CMR under general anesthesia were prospectively enrolled. The 3DE images were acquired at the conclusion of the CMR. Twenty-seven of 29 3DE data sets (93%) were optimal for 3DE assessment. Two blinded and independent observers performed 3DE measurements of volume, mass, and ejection fraction. The 3DE end-diastolic volume correlated well (r=0.96) but was smaller than CMR by 9% (P<0.01), and 3DE ejection fraction was smaller than CMR by 11% (P<0.01). There was no significant difference in measurements of end-systolic volume and mass. The 3DE interobserver differences for mass and volumes were not significant except for ejection fraction (8% difference; P<0.05). Intraobserver differences were not significant. In young pediatric patients with a functional single ventricle, matrix-array 3DE measurements of mass and volumes compare well with those obtained by CMR. 3DE will provide an important modality for the serial analysis of ventricular size and performance in young patients with functional single ventricles.

Finite element stress analysis of the human left ventricle whose irregular shape is developed from single plane cineangiocardiogram

NASA Technical Reports Server (NTRS)

Ghista, D. N.; Hamid, M. S.

1977-01-01

The three-dimensional left ventricular chamber geometrical model is developed from single plane cineangiocardiogram. This left ventricular model is loaded by an internal pressure monitored by cardiac catheterization. The resulting stresses in the left ventricular model chamber's wall are determined by computerized finite element procedure. For the discretization of this left ventricular model structure, a 20-node, isoparametric finite element is employed. The analysis and formulation of the computerised procedure is presented in the paper, along with the detailed algorithms and computer programs. The procedure is applied to determine the stresses in a left ventricle at an instant, during systole. Next, a portion (represented by a finite element) of this left ventricular chamber is simulated as being infarcted by making its active-state modulus value equal to its passive-state value; the neighbouring elements are shown to relieve the 'infarcted' element of stress by themselves taking on more stress.

Role of myocardial hypertrophy on acute and chronic right ventricular performance in relation to chronic volume overload in a porcine model: relevance for the surgical management of tetralogy of Fallot.

PubMed

Bove, Thierry; Vandekerckhove, Kristof; Bouchez, Stefaan; Wouters, Patrick; Somers, Pamela; Van Nooten, Guido

2014-06-01

The age for correction of tetralogy of Fallot has progressively declined to the postnatal period, often despite an increased rate of transannular patch repair. However, the long-term effect of premature exposure to chronic pulmonary insufficiency on the right ventricle remains unknown. On the basis of the relationship between the duration of pressure overload and age, the role of previous pressure load-related hypertrophy on right ventricular (RV) performance after chronic volume overload was investigated in a porcine model. RV hypertrophy (RVH), induced by pulmonary artery banding, was studied in pigs with (RVH plus pulmonary insufficiency [PI]) and without (RVH) subsequent PI. The effect of volume overload was compared between these 2 groups and pigs without RVH but with PI and controls (sham). Both acute and chronic effects on RV function were studied using conductance technology and validated using echocardiography. After chronic volume overload, the end-systolic and end-diastolic volumes were smaller in the RVH+PI group than in the PI group, including a lower pulmonary regurgitation fraction (25% ± 5% vs 35% ± 5%; P = .002). RVH resulted in better preserved systolic function, confirmed by an increased preload recruitable stroke work slope (14.7 ± 1.8 vs 9.3 ± 1.3 Mw.s/mL; P = .025) and higher RV ejection fraction (51% ± 3% vs 45% ± 4%; P = .05). Myocardial stiffness was impaired in the RVH+PI group versus the PI group (β, 0.19 ± 0.03 vs 0.12 ± 0.02 mL(-1); P = .001), presenting restrictive physiology only in the condition associating RVH and PI. The results of the present study have demonstrated that RVH attenuates the RV remodeling process related to chronic PI. It enables better preservation of contractility but at the cost of sustained diastolic impairment. These findings might help to determine the timing and strategy for repair of tetralogy of Fallot when RV outflow tract morphology indicates a definite need for transannular reconstruction. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Isovolumic relaxation period as an index of left ventricular relaxation under different afterload conditions--comparison with the time constant of left ventricular pressure decay in the dog.

PubMed

Ochi, H; Ikuma, I; Toda, H; Shimada, T; Morioka, S; Moriyama, K

1989-12-01

In order to determine whether isovolumic relaxation period (IRP) reflects left ventricular relaxation under different afterload conditions, 17 anesthetized, open chest dogs were studied, and the left ventricular pressure decay time constant (T) was calculated. In 12 dogs, angiotensin II and nitroprusside were administered, with the heart rate constant at 90 beats/min. Multiple linear regression analysis showed that the aortic dicrotic notch pressure (AoDNP) and T were major determinants of IRP, while left ventricular end-diastolic pressure was a minor determinant. Multiple linear regression analysis, correlating T with IRP and AoDNP, did not further improve the correlation coefficient compared with that between T and IRP. We concluded that correction of the IRP by AoDNP is not necessary to predict T from additional multiple linear regression. The effects of ascending aortic constriction or angiotensin II on IRP were examined in five dogs, after pretreatment with propranolol. Aortic constriction caused a significant decrease in IRP and T, while angiotensin II produced a significant increase in IRP and T. IRP was affected by the change of afterload. However, the IRP and T values were always altered in the same direction. These results demonstrate that IRP is substituted for T and it reflects left ventricular relaxation even in different afterload conditions. We conclude that IRP is a simple parameter easily used to evaluate left ventricular relaxation in clinical situations.

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.

Obese subjects show sex-specific differences in right ventricular hypertrophy.

PubMed

Rider, Oliver J; Lewis, Andrew J M; Lewandowski, Adam J; Ntusi, Ntobeko; Nethononda, Richard; Petersen, Steffen E; Francis, Jane M; Pitcher, Alex; Banerjee, Rajarshi; Leeson, Paul; Neubauer, Stefan

2015-01-01

As right ventricular (RV) remodeling in obesity remains underinvestigated, and the impact of left ventricular (LV) diastolic dysfunction on RV hypertrophy is unknown, we aimed to investigate whether (1) sex-specific patterns of RV remodeling exist in obesity and (2) LV diastolic dysfunction in obesity is related to RV hypertrophy. Seven hundred thirty-nine subjects (women, n=345; men, n=394) without identifiable cardiovascular risk factors (body mass index [BMI], 15.3-59.2 kg/m2) underwent cardiovascular magnetic resonance (1.5 T) to measure RV mass (g), RV end-diastolic volume (mL), RV mass/volume ratio, and LV diastolic peak filling rate (mL/s). All subjects were normotensive (average, 119±11/73±8 mm Hg), normoglycaemic (4.8±0.5 mmol/L), and normocholesterolaemic (4.8±0.9 mmol/L) at the time of scanning. Across both sexes, there was a moderately strong positive correlation between BMI and RV mass (men, +0.8 g per BMI point increase; women, +1.0 g per BMI point increase; both P<0.001). Whereas women exhibited RV cavity dilatation (RV end-diastolic volume, +1.0 mL per BMI point increase; P<0.001), BMI was not correlated with RV end-diastolic volume in men (R=0.04; P=0.51). Concentric RV remodeling was present in both sexes, with RV mass/volume ratio being positively correlated to BMI (men, R=0.41; women, R=0.51; both P<0.001). Irrespective of sex, the LV peak filling rate was negatively correlated with both RV mass (men, R=-0.43; women, R=-0.44; both P<0.001) and RV mass/volume ratio (men, R=-0.37; women, R=-0.35; both P<0.001). A sex difference in RV remodeling exists in obesity. Whereas men exhibit concentric RV remodeling, women exhibit a mixed pattern of eccentric and concentric remodeling. Regardless of sex, reduced LV diastolic function is associated with concentric RV remodeling. © 2014 American Heart Association, Inc.

Brain and cord myelin water imaging: a progressive multiple sclerosis biomarker

PubMed Central

Kolind, Shannon; Seddigh, Arshia; Combes, Anna; Russell-Schulz, Bretta; Tam, Roger; Yogendrakumar, Vignan; Deoni, Sean; Sibtain, Naomi A.; Traboulsee, Anthony; Williams, Steven C.R.; Barker, Gareth J.; Brex, Peter A.

2015-01-01

Objectives Conventional magnetic resonance imaging (MRI) is used to diagnose and monitor inflammatory disease in relapsing remitting (RR) multiple sclerosis (MS). In the less common primary progressive (PP) form of MS, in which focal inflammation is less evident, biomarkers are still needed to enable evaluation of novel therapies in clinical trials. Our objective was to characterize the association — across the brain and cervical spinal cord — between clinical disability measures in PPMS and two potential biomarkers (one for myelin, and one for atrophy, both resulting from the same imaging technique). Methods Multi-component driven equilibrium single pulse observation of T1 and T2 (mcDESPOT) MRI of the brain and cervical spinal cord were obtained for 15 PPMS patients and 11 matched controls. Data were analysed to estimate the signal related to myelin water (VFM), as well as volume measurements. MS disability was assessed using the Multiple Sclerosis Functional Composite score, which includes measures of cognitive processing (Paced Auditory Serial Addition Test), manual dexterity (9-Hole Peg Test) and ambulatory function (Timed 25-Foot Walk); and the Expanded Disability Status Scale. Results Brain and spinal cord volumes were different in PPMS compared to controls, particularly ventricular (+ 46%, p = 0.0006) and cervical spinal cord volume (− 16%, p = 0.0001). Brain and spinal cord myelin (VFM) were also reduced in PPMS (brain: − 11%, p = 0.01; spine: − 19%, p = 0.000004). Cognitive processing correlated with brain ventricular volume (p = 0.009). Manual dexterity correlated with brain ventricular volume (p = 0.007), and both brain and spinal cord VFM (p = 0.01 and 0.06, respectively). Ambulation correlated with spinal cord volume (p = 0.04) and spinal cord VFM (p = 0.04). Interpretation In this study we demonstrated that mcDESPOT can be used to measure myelin and atrophy in the brain and spinal cord. Results correlate well with clinical disability scores in PPMS representing cognitive, fine motor and ambulatory disability. PMID:26594633