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1

Relationships between left heart chamber dilatation on echocardiography and left-to-right ventricle shunting quantified by cardiac catheterization in children with ventricular septal defects.  

PubMed

Left atrium and/or left ventricle dilatation on echocardiography is considered to be an indication for closure of ventricular septal defects (VSD). No study has addressed the accuracy of using dilated left heart chambers when defining significant left-to-right shunting quantified by cardiac catheterization in isolated small or moderate VSDs. In this study, the relation between dilated left heart chambers, measured by echocardiography, and left-to-right ventricle shunting, quantified by cardiac catheterization, was evaluated in patients with isolated VSD. The medical records of all patients with isolated VSD who had undergone catheterization from 1996 to 2010 were examined retrospectively. Normative data for left heart chambers adjusted for body weight (BW) and body surface area (BSA) were used. The pulmonary-to-systemic flow ratio (Qp:Qs) was calculated by an oximetry technique. A total of 115 patients (mean age 7.3 ± 5 years) fulfilled the inclusion criteria. There was a statistically significant difference in terms of Qp:Qs between the patient groups with normal and dilated left heart chambers, when adjusted for BW and BSA (p = 0.001 and p = 0.002, respectively). But the relationships between Qp:Qs and left heart chamber sizes on echocardiography were not strong enough to be useful for making surgical decisions, as left heart chamber dilatation was not significantly associated with Qp:Qs ? 2 (p = 0.349 when adjusted for BW, p = 0.107 when adjusted for BSA). Left heart chamber dilatation was significantly associated with Qp:Qs ? 1.5 only when it was adjusted for BSA (for BW p = 0.022, for BSA p = 0.006). As a result, left heart chamber dilatation measured by echocardiography does not show significant left-to-right ventricle shunting, as quantified by catheterization. We still advocate that catheter angiography should be undertaken when left heart chambers are dilated in echocardiography in order to make decisions about closing small- to moderate-sized VSD. PMID:24259011

Gokalp, Selman; Guler Eroglu, Ayse; Saltik, Levent; Koca, Bulent

2014-04-01

2

Dual-chamber cardiac pacemaker tester.  

PubMed

To investigate the operation of dual-chamber cardiac pacemakers, a pacemaker tester is developed that is able to examine pacemaker parameters, demand modes and rate-adaptive modes. The tester generates simplified electrograms and responds to pacemaker pulses in a closed-loop simulation. The authors describe the hardware and the software algorithm of the tester. To demonstrate the capabilities of the tester, four tests are presented, together with their results on a rate-adaptive dual-chamber pacemaker. PMID:9684467

Galuschky, C W; Webster, J G

1998-03-01

3

The evolutionary origin of cardiac chambers.  

PubMed

Identification of cardiac mechanisms of retinoic acid (RA) signaling, description of homologous genetic circuits in Ciona intestinalis and consolidation of views on the secondary heart field have fundamental, but still unrecognized implications for vertebrate heart evolution. Utilizing concepts from evolution, development, zoology, and circulatory physiology, we evaluate the strengths of animal models and scenarios for the origin of vertebrate hearts. Analyzing chordates, lower and higher vertebrates, we propose a paradigm picturing vertebrate hearts as advanced circulatory pumps formed by segments, chambered or not, devoted to inflow or outflow. We suggest that chambers arose not as single units, but as components of a peristaltic pump divided by patterning events, contrasting with scenarios assuming that chambers developed one at a time. Recognizing RA signaling as a potential mechanism patterning cardiac segments, we propose to use it as a tool to scrutinize the phylogenetic origins of cardiac chambers within chordates. Finally, we integrate recent ideas on cardiac development such as the ballooning and secondary/anterior heart field paradigms, showing how inflow/outflow patterning may interact with developmental mechanisms suggested by these models. PMID:15572135

Simões-Costa, Marcos S; Vasconcelos, Michelle; Sampaio, Allysson C; Cravo, Roberta M; Linhares, Vania L; Hochgreb, Tatiana; Yan, Chao Y I; Davidson, Brad; Xavier-Neto, José

2005-01-01

4

Double-chambered left ventricle in a cat.  

PubMed

Double-chambered left ventricle is a rare congenital disorder in which the left ventricular cavity is subdivided into two cavities by an anomalous septum or muscle band. We describe a case of double-chambered left ventricle, most likely caused by the presence of excessive left ventricular bands, in an asymptomatic cat. PMID:24816328

Smith, Paul J; Tarazi, Marwan N; Ho, Siew Yen

2014-06-01

5

Unexplained double-chambered left ventricle associated with contracting right ventricular aneurysm and right atrial enlargement.  

PubMed

In this article, we describe a double-chambered left ventricle (LV) associated with a functional right ventricular (RV) aneurysm and right atrial (RA) enlargement in an asymptomatic 24-year-old woman with a family history of sudden cardiac death. We will discuss the differential diagnosis, genetic testing and possible prognostic implications. PMID:24299065

Finocchiaro, Gherardo; Murphy, Daniel; Pavlovic, Aleksandra; Haddad, Francois; Shiran, Hadas; Sinagra, Gianfranco; Ashley, Euan A; Knowles, Joshua W

2014-03-01

6

Double-chambered left ventricle in an asymptomatic adult patient.  

PubMed

This article shows a case of double-chambered left ventricle in asymptomatic 60-year-old man. This rare congenital entity is usually diagnosed in the neonatal or paediatric age, and it is characterized by the subdivision of the left ventricle in two chambers by an abnormal septum or muscle band. Differential diagnosis includes two other congenital left ventricular (LV) outpouching entities, such as diverticulum and aneurysm. As shown in our case, double-chambered left ventricle exhibits mixed features. A comprehensive cardiovascular magnetic imaging study is useful in the distinction of these closely related congenital diseases and, therefore, important for the correct final diagnosis. PMID:22135091

Masci, Pier Giorgio; Pucci, Angela; Fontanive, Paolo; Coceani, Michele; Marraccini, Paolo; Lombardi, Massimo

2012-03-01

7

Cardiac MR Elastography: Comparison with left ventricular pressure measurement  

Microsoft Academic Search

PURPOSE OF STUDY: To compare magnetic resonance elastography (MRE) with ventricular pressure changes in an animal model. METHODS: Three pigs of different cardiac physiology (weight, 25 to 53 kg; heart rate, 61 to 93 bpm; left ventricular [LV] end-diastolic volume, 35 to 70 ml) were subjected to invasive LV pressure measurement by catheter and noninvasive cardiac MRE. Cardiac MRE was

Thomas Elgeti; Michael Laule; Nikola Kaufels; Jörg Schnorr; Bernd Hamm; Abbas Samani; Jürgen Braun; Ingolf Sack

2009-01-01

8

The evolutionary origin of cardiac chambers  

Microsoft Academic Search

Identification of cardiac mechanisms of retinoic acid (RA) signaling, description of homologous genetic circuits in Ciona intestinalis and consolidation of views on the secondary heart field have fundamental, but still unrecognized implications for vertebrate heart evolution. Utilizing concepts from evolution, development, zoology, and circulatory physiology, we evaluate the strengths of animal models and scenarios for the origin of vertebrate hearts.

Marcos S. Simões-Costa; Michelle Vasconcelos; Allysson C. Sampaio; Roberta M. Cravo; Vania L. Linhares; Tatiana Hochgreb; Chao Y. I. Yan; Brad Davidson; José Xavier-Neto

2005-01-01

9

Coronary anomaly with a left ventricular accessory chamber: Is it left ventricular aneurysm or diverticulum?  

PubMed

A 60-year-old male hypertensive was suspected to have post myocardial infarction left ventricular aneurysm. His transthoracic echocardiogram performed elsewhere reported an inferior wall left ventricular aneurysm. He was referred for coronary angiography. His coronary angiogram and repeat transthoracic echocardiogram demonstrated an accessory chamber arising from mid-inferior wall synchronously contracting with the left ventricle suggesting a diverticulum. In addition, he had anomalous coronary arteries with coronary artery disease. His electrocardiogram did not reveal any features suggestive of a post infarct aneurysm. This case illustrates the importance of a comprehensive clinical and echocardiographic examination with a broad differential thought process. PMID:23960694

Panduranga, Prashanth; Al-Riyami, Abdullah Amour

2012-07-01

10

Pulmonary Hypertension Related to Left-Sided Cardiac Pathology  

PubMed Central

Pulmonary hypertension (PH) is the end result of a variety of diverse pathologic processes. The chronic elevation in pulmonary artery pressure often leads to right ventricular pressure overload and subsequent right ventricular failure. In patients with left-sided cardiac disease, PH is quite common and associated with increased morbidity and mortality. This article will review the literature as it pertains to the epidemiology, pathogenesis, and diagnosis of PH related to aortic valve disease, mitral valve disease, left ventricular systolic and diastolic dysfunction, and pulmonary veno-occlusive disease. Moreover, therapeutic strategies, which focus on treating the underlying cardiac pathology will be discussed.

Kiefer, Todd L.; Bashore, Thomas M.

2011-01-01

11

Automated left ventricular segmentation in cardiac MRI  

Microsoft Academic Search

We present an automated left ventricular (LV) myocardial boundary extraction method. Automatic localization of the LV is achieved using a motion map and an expectation maximization algorithm. The myocardial region is then segmented using an intensity-based fuzzy affinity map and the myocardial contours are extracted by cost minimization through a dynamic programming approach. The results from the automated algorithm compared

Amol Pednekar; Uday Kurkure; Raja Muthupillai; Scott Flamm; Ioannis A. Kakadiaris

2006-01-01

12

Thoracoscopic Left Ventricular Lead Implantation in Cardiac Resynchronization Therapy  

PubMed Central

Cardiac resynchronization therapy is known to reduce morbidity and mortality in patients with advanced heart failure as a result of dyssynchrony and systolic dysfunction of the left ventricle. Placement of the left ventricular (LV) lead via the coronary sinus can be difficult. When LV lead implantation is difficult, a video-assisted epicardial approach can be a good alternative. Although there are several reports of video-assisted epicardial LV lead implantation, mini-thoracotomy and lead implantation under direct vision have been used in most series. A 49-yr-old woman with dilated cardiomyopathy underwent the video-assisted epicardial LV lead implantation because percutaneous transvenous approach was difficult due to small cardiac veins. The patient was discharged without problems and showed improved cardiac function at the 3 follow-up months. We report the first successful total thoracoscopic LV lead implantation (without mini-thoracotomy) in Korea.

Jeong, Dong Seop; Park, Pyo Won; Lee, Young Tak; Park, Seung-Jung; Kim, June Soo

2012-01-01

13

Automated left ventricular segmentation in cardiac MRI.  

PubMed

We present an automated left ventricular (LV) myocardial boundary extraction method. Automatic localization of the LV is achieved using a motion map and an expectation maximization algorithm. The myocardial region is then segmented using an intensity-based fuzzy affinity map and the myocardial contours are extracted by cost minimization through a dynamic programming approach. The results from the automated algorithm compared against the experienced radiologists using Bland and Altman analysis were found to have consistent mean bias of 7% and limits of agreement comparable to the inter-observer variability inherent in the manual method. PMID:16830947

Pednekar, Amol; Kurkure, Uday; Muthupillai, Raja; Flamm, Scott; Kakadiaris, Ioannis A

2006-07-01

14

Left Ventricle Volume Measurements in Cardiac Micro-CT  

PubMed Central

Micro-CT based cardiac function estimation in small animals requires measurement of left ventricle (LV) volume at multiple time points during the cardiac cycle. Measurement accuracy depends on the image resolution, its signal and noise properties, and the analysis procedure. This work compares the accuracy of the Otsu thresholding and a region sampled binary mixture approach, for live mouse LV volume measurement using 100 micron resolution datasets. We evaluate both analysis methods after varying the volume of injected contrast agent and the number of projections used for CT reconstruction with a goal of permitting reduced levels of both x-ray and contrast agent doses.

Badea, Cristian T.; Wetzel, Arthur W.; Mistry, Nilesh; Pomerantz, Stuart; Nave, Demian; Johnson, G. Allan

2008-01-01

15

Kinematic modeling-based left ventricular diastatic (passive) chamber stiffness determination with in-vivo validation.  

PubMed

The slope of the diastatic pressure-volume relationship (D-PVR) defines passive left ventricular (LV) stiffness ?. Although ? is a relative measure, cardiac catheterization, which is an absolute measurement method, is used to obtain the former. Echocardiography, including transmitral flow velocity (Doppler E-wave) analysis, is the preferred quantitative diastolic function (DF) assessment method. However, E-wave analysis can provide only relative, rather than absolute pressure information. We hypothesized that physiologic mechanism-based modeling of E-waves allows derivation of the D-PVR(E-wave) whose slope, ?(E-wave), provides E-wave-derived diastatic, passive chamber stiffness. Our kinematic model of filling and Bernoulli's equation were used to derive expressions for diastatic pressure and volume on a beat-by-beat basis, thereby generating D-PVR(E-wave), and ?(E-wave). For validation, simultaneous (conductance catheter) P-V and echocardiographic E-wave data from 30 subjects (444 total cardiac cycles) having normal LV ejection fraction (LVEF) were analyzed. For each subject (15 beats average) model-predicted ?(E-wave) was compared to experimentally measured ?(CATH) via linear regression yielding as follows: ?(E-wave) = ??(CATH) + b (R(2) = 0.92), where, ? = 0.995 and b = 0.02. We conclude that echocardiographically determined diastatic passive chamber stiffness, ?(E-wave), provides an excellent estimate of simultaneous, gold standard (P-V)-defined diastatic stiffness, ?(CATH). Hence, in chambers at diastasis, passive LV stiffness can be accurately determined by means of suitable analysis of Doppler E-waves (transmitral flow). PMID:22065203

Mossahebi, Sina; Kovács, Sándor J

2012-05-01

16

Cardiac rhabdomyoma mimicking haemodynamics of hypoplastic left heart syndrome.  

PubMed

Cardiac rhabdomyomas are rare and often regress spontaneously. However, the management of rhabdomyoma with severe inflow and outflow obstructions is a challenge. An infant with a massive left ventricular rhabdomyoma mimicking the haemodynamics of hypoplastic left heart syndrome is reported. Surgery could not be contemplated because the mitral valve leaflets and chordae were imbedded in the tumour mass. The arterial duct (AD) was kept open to perfuse the systemic circulation and palliations with pulmonary artery branch banding and AD stenting were planned. However; while waiting for spontaneous regression of the tumour, the child died of circulatory collapse when 4 weeks old. PMID:25029876

El-Segaier, Milad; Galal, Mohammed O

2014-06-01

17

Cardiac MR Elastography: Comparison with left ventricular pressure measurement  

PubMed Central

Purpose of study To compare magnetic resonance elastography (MRE) with ventricular pressure changes in an animal model. Methods Three pigs of different cardiac physiology (weight, 25 to 53 kg; heart rate, 61 to 93 bpm; left ventricular [LV] end-diastolic volume, 35 to 70 ml) were subjected to invasive LV pressure measurement by catheter and noninvasive cardiac MRE. Cardiac MRE was performed in a short-axis view of the heart and applying a 48.3-Hz shear-wave stimulus. Relative changes in LV-shear wave amplitudes during the cardiac cycle were analyzed. Correlation coefficients between wave amplitudes and LV pressure as well as between wave amplitudes and LV diameter were determined. Results A relationship between MRE and LV pressure was observed in all three animals (R2 ? 0.76). No correlation was observed between MRE and LV diameter (R2 ? 0.15). Instead, shear wave amplitudes decreased 102 ± 58 ms earlier than LV diameters at systole and amplitudes increased 175 ± 40 ms before LV dilatation at diastole. Amplitude ratios between diastole and systole ranged from 2.0 to 2.8, corresponding to LV pressure differences of 60 to 73 mmHg. Conclusion Externally induced shear waves provide information reflecting intraventricular pressure changes which, if substantiated in further experiments, has potential to make cardiac MRE a unique noninvasive imaging modality for measuring pressure-volume function of the heart.

Elgeti, Thomas; Laule, Michael; Kaufels, Nikola; Schnorr, Jorg; Hamm, Bernd; Samani, Abbas; Braun, Jurgen; Sack, Ingolf

2009-01-01

18

Simulating left ventricular fluid-solid mechanics through the cardiac cycle under LVAD support  

NASA Astrophysics Data System (ADS)

In this study we have integrated novel modifications of the standard Newton-Raphson/line search algorithm and optimisation of the interpolation scheme at the fluid-solid boundary to enable the simulation of fluid-solid interaction within the cardiac left ventricle under the support of a left ventricular assist device (LVAD). The line search modification combined with Jacobian reuse produced close to an order of magnitude improvement in computational time across both test and whole heart simulations. Optimisation of element interpolation schemes on the fluid-solid boundary highlights the impact this choice can have on problem stability and demonstrates that, in contrast to linear fluid elements, higher order interpolation produces improved error reduction per degree of freedom. Incorporating these modifications enabled a full heart cycle under LVAD support to be modelled. Results from these simulations show that there is slower clearance of blood entering the chamber during early compared to late diastole under conditions of constant LVAD flow.

McCormick, M.; Nordsletten, D. A.; Kay, D.; Smith, N. P.

2013-07-01

19

Dose Distribution in the Heart and Cardiac Chambers Following 4-field Radiation Therapy of Breast Cancer: a Retrospective Study  

PubMed Central

Purpose: To evaluate cardiac doses in breast cancer patients with stage II/III treated with 4-field radiotherapy based on computed tomography (CT) dose planning. Methods and Materials: Based on archived CT images, whole heart and cardiac chamber radiation doses were analyzed in 216 (111 left-sided and 105 right-sided) mastectomized or lumpectomized breast cancer patients treated at a single institution, the Norwegian Radium Hospital, between 2000–2002. Individual dose volume histograms for the whole heart and for the four cardiac chambers were obtained, and mean, median and maximum doses to these structures were calculated. The dose (Gy) delivered to the 5% of the volume of each cardiac structure (D5%), and the volume percentage of each structure receiving ? 25 Gy (V25Gy) were reported. Normal tissue complication probability (NTCP) calculations were used to estimate the risk for ischemic heart disease (IHD). Results: Cohort-based medians of the whole heart mean dose (Dmean) for left- and right-sided tumors were 3.2 Gy and 1.3 Gy, respectively, with similar ventricular but lower atrial values. The atrial doses did not differ according to laterality of the breast tumor. In 13 patients with left-sided cancer, 5% of the heart volume was exposed to >25 Gy. The NTCP estimates were generelly low, with a maximum of 2.8%. Conclusions: During adjuvant CT-based locoregional radiotherapy of women with breast cancer, the cardiac radiation doses are, at the group level, below recommended threshold values (D5% < 25 Gy), though individual patients with left-sided disease may exceed these limits.

Johansen, Safora; Tjessem, Kristin H.; Fossa, Kristian; Bosse, Gerhard; Danielsen, Turi; Malinen, Eirik; Fossa, Sophie D.

2013-01-01

20

Double-chambered left ventricle due to fibroelastotic membrane: an unusual case.  

PubMed

We describe a rare case of a double-chambered left ventricle caused by a fibroelastotic membrane that was clearly delineated using echocardiography and magnetic resonance imaging, which resulted in successful surgical correction. PMID:21102355

Rajiah, Prabhakar; Thomas, James; Smedira, Nicholas; Desai, Milind Y

2012-01-01

21

Semi-automatic algorithm for construction of the left ventricular area variation curve over a complete cardiac cycle  

PubMed Central

Background Two-dimensional echocardiography (2D-echo) allows the evaluation of cardiac structures and their movements. A wide range of clinical diagnoses are based on the performance of the left ventricle. The evaluation of myocardial function is typically performed by manual segmentation of the ventricular cavity in a series of dynamic images. This process is laborious and operator dependent. The automatic segmentation of the left ventricle in 4-chamber long-axis images during diastole is troublesome, because of the opening of the mitral valve. Methods This work presents a method for segmentation of the left ventricle in dynamic 2D-echo 4-chamber long-axis images over the complete cardiac cycle. The proposed algorithm is based on classic image processing techniques, including time-averaging and wavelet-based denoising, edge enhancement filtering, morphological operations, homotopy modification, and watershed segmentation. The proposed method is semi-automatic, requiring a single user intervention for identification of the position of the mitral valve in the first temporal frame of the video sequence. Image segmentation is performed on a set of dynamic 2D-echo images collected from an examination covering two consecutive cardiac cycles. Results The proposed method is demonstrated and evaluated on twelve healthy volunteers. The results are quantitatively evaluated using four different metrics, in a comparison with contours manually segmented by a specialist, and with four alternative methods from the literature. The method's intra- and inter-operator variabilities are also evaluated. Conclusions The proposed method allows the automatic construction of the area variation curve of the left ventricle corresponding to a complete cardiac cycle. This may potentially be used for the identification of several clinical parameters, including the area variation fraction. This parameter could potentially be used for evaluating the global systolic function of the left ventricle.

2010-01-01

22

Effect of cardiac resynchronization therapy on left atrial appendage function and pulmonary venous flow pattern  

Microsoft Academic Search

BackgroundPrevious studies have shown improvement in left ventricular function and development of the reverse remodeling in the left ventricle and left atrium after cardiac resynchronization therapy (CRT). The aim of this study was to investigate the effect of CRT on left atrial appendage (LAA) function and pulmonary venous flow pattern.

Ahmet Vural; Aysen Agacdiken; Dilek Ural; Tayfun Sahin; Guliz Kozdag; Göksel Kahraman; Ertan Ural; Haluk Akbas; Kaya Suzer; Baki Komsuoglu

2005-01-01

23

Reduction of cardiac volume in left-breast treatment fields by respiratory maneuvers: a CT study  

Microsoft Academic Search

Purpose: A previous study of healthy female volunteers suggested that deep inspiratory breath holding can reduce the cardiac volume in the treatment portals for left-breast cancer treatment. The reduction of irradiated cardiac volume may be important considering the reported late cardiac morbidity and mortality and the frequent coexistent use of potentially cardiotoxic chemotherapy in breast cancer patients. In the present

Hsiao-Ming Lu; Ethan Cash; Ming Hui Chen; Lee Chin; Warren J Manning; Jay Harris; Bruce Bornstein

2000-01-01

24

Left Ventricular Systolic Function and Outcome After In-Hospital Cardiac Arrest  

Microsoft Academic Search

Background—The effect of prearrest left ventricular ejection fraction (LVEF) on outcome after cardiac arrest is unknown. Methods and Results—During a 26-month period, Utstein-style data were prospectively collected on 800 consecutive inpatient adult index cardiac arrests in an observational, single-center study at a tertiary cardiac care hospital. Prearrest echocardiograms were performed on 613 patients (77%) at 1114 days before the cardiac

Maria M. Gonzalez; Robert A. Berg; Vinay M. Nadkarni; Caio B. Vianna; Karl B. Kern; Sergio Timerman; Jose A. Ramires

2010-01-01

25

Morphological and Volumetric Analysis of Left Atrial Appendage and Left Atrium: Cardiac Computed Tomography-Based Reproducibility Assessment  

PubMed Central

Objectives Left atrial appendage (LAA) dilatation and morphology may influence an individual's risk for intracardiac thrombi and ischemic stroke. LAA size and morphology can be evaluated using cardiac computed tomography (cCT). The present study evaluated the reproducibility of LAA volume and morphology assessments. Methods A total of 149 patients (47 females; mean age 60.9±10.6 years) with suspected cardioembolic stroke/transient ischemic attack underwent cCT. Image quality was rated based on four categories. Ten patients were selected from each image quality category (N?=?40) for volumetric reproducibility analysis by two individual readers. LAA and left atrium (LA) volume were measured in both two-chamber (2CV) and transversal view (TV) orientation. Intertechnique reproducibility was assessed between 2CV and TV (200 measurement pairs). LAA morphology (A?=?Cactus, B?=?ChickenWing, C?=?WindSock, D?=?CauliFlower), LAA opening height, number of LAA lobes, trabeculation, and orientation of the LAA tip was analysed in all study subjects by three individual readers (447 interobserver measurement pairs). The reproducibility of volume measurements was assessed by intra-class correlation (ICC) and the reproducibility of LAA morphology assessments by Cohen's kappa. Results The intra-observer and interobserver reproducibility of LAA and LA volume measurements was excellent (ICCs>0.9). The LAA (ICC?=?0.954) and LA (ICC?=?0.945) volume measurements were comparable between 2CV and TV. Morphological classification (??=?0.24) and assessments of LAA opening height (??=?0.1), number of LAA lobes (??=?0.16), trabeculation (??=?0.15), and orientation of the LAA tip (??=?0.37) was only slightly to fairly reproducible. Conclusions LA and LAA volume measurements on cCT provide excellent reproducibility, whereas visual assessment of LAA morphological features is challenging and results in unsatisfactory agreement between readers.

Taina, Mikko; Korhonen, Miika; Haataja, Mika; Muuronen, Antti; Arponen, Otso; Hedman, Marja; Jakala, Pekka; Sipola, Petri; Mustonen, Pirjo; Vanninen, Ritva

2014-01-01

26

Extracorporeal life support with an integrated left ventricular vent in children with a low cardiac output.  

PubMed

Background: The aim of this study was to evaluate our experience in central extracorporeal life support with an integrated left ventricular vent in children with cardiac failure. Methods: Eight children acquired extracorporeal life support with a left ventricular vent, either after cardiac surgery (n = 4) or during an acute cardiac illness (n = 4). The ascending aorta and right atrium were cannulated. The left ventricular vent was inserted through the right superior pulmonary vein and connected to the venous line on the extracorporeal life support such that active left heart decompression was achieved. Results: No patient died while on support, seven patients were successfully weaned from it and one patient was transitioned to a biventricular assist device. The median length of support was 6 days (range 5-10 days). One patient died while in the hospital, despite successful weaning from extracorporeal life support. No intra-cardiac thrombus or embolic stroke was observed. No patient developed relevant intracranial bleeding resulting in neurological dysfunction during and after extracorporeal life support. Conclusions: In case of a low cardiac output and an insufficient inter-atrial shunt, additional left ventricular decompression via a vent could help avoid left heart distension and might promote myocardial recovery. In pulmonary dysfunction, separate blood gas analyses from the venous cannula and the left ventricular vent help detect possible coronary hypoxia when the left ventricle begins to recover. We recommend the use of central extracorporeal life support with an integrated left ventricular vent in children with intractable cardiac failure. PMID:23919969

Sandrio, Stany; Springer, Wolfgang; Karck, Matthias; Gorenflo, Matthias; Weymann, Alexander; Ruhparwar, Arjang; Loukanov, Tsvetomir

2014-08-01

27

Midwall Mechanics Are Improved After Regression of Hypertensive Left Ventricular Hypertrophy and Normalization of Chamber Geometry  

Microsoft Academic Search

Background—It is still unclear whether substantial regression of hypertensive left ventricular hypertrophy (LVH) and normalization of chamber geometry are associated with improved left ventricular (LV) myocardial function. Methods and Results—Midwall mechanics were evaluated in 152 patients undergoing 1 year of effective antihypertensive treatment. Two-dimensionally directed M-mode echocardiography was performed as follows: (1) after a 4-week placebo \\

Stefano Perlini; Maria Lorenza Muiesan; Cesare Cuspidi; Lorena Sampieri; Bruno Trimarco; Gerard P. Aurigemma; Enrico Agabiti-Rosei; Giuseppe Mancia

28

Minimally invasive left ventricular assist device explantation after cardiac recovery: surgical technical considerations.  

PubMed

The new generation of left ventricular assist devices (LVADs) has enabled minimally invasive surgical procedures for implantation. Herein we present two alternative approaches for minimally invasive LVAD explantation following cardiac recovery, avoiding a sternotomy and improving patient safety. PMID:24571624

Schmitto, Jan D; Rojas, Sebastian V; Hanke, Jasmin S; Avsar, Murat; Haverich, Axel

2014-06-01

29

Normal size left ventricle on antenatal scan in lethal hypoplastic left heart syndrome  

Microsoft Academic Search

We present a case of lethal hypoplastic left heart syndrome missed at routine 20-week antenatal ultrasound examination because the left ventricle was of normal size on the standard four-chamber cardiac view. Hypoplastic left heart syndrome includes a spectrum of cardiac malformations. This case illustrates the difficulty in excluding the diagnosis of hypoplastic left heart syndrome on a single view from

N. G. Anderson; J. Brown

1991-01-01

30

The role of vitamin D in left ventricular hypertrophy and cardiac function  

Microsoft Academic Search

The role of vitamin D in left ventricular hypertrophy and cardiac function. Cardiovascular disease is the leading cause of death among patients with end-stage renal disease (ESRD). Traditional cardiac risk factors, as well as other factors specific to the ESRD population such as hyperphosphatemia, elevated calcium and phosphate product, abnormal lipid metabolism, hyperhomocysteinemia, and chronic inflammation play a role in

Steven G. Achinger; JUAN CARLOS AYUS

2005-01-01

31

Localization and Segmentation of Left Ventricle in Cardiac Cine-MR Images  

Microsoft Academic Search

Accurate delineation of the left ventricular myocardial boundaries on cardiac cine magnetic resonance (MR) images is essential for volumetric and functional cardiac analysis. Automated myocardial contour delineation often suffers from misalignment of slices, nonuniform coil sensitivity, blood-flow-related inter- and intraslice intensity inhomogeneities, blurring due to motion, partial voluming, and a need to circumscribe the papillary muscles and the trabeculae. In

Uday Kurkure; Amol Pednekar; Raja Muthupillai; Scott D. Flamm; Ioannis A. Kakadiaris

2009-01-01

32

Unusual sudden cardiac death from an anomalous left coronary artery from the right sinus of Valsalva.  

PubMed

A left coronary artery arising from the right sinus of Valsalva is a rare congenital coronary anomaly. We report a case of a 5-year-old boy with an anomalous left coronary artery from the right sinus of Valsalva whose presenting sign was cardiac arrest. There is no reported instance of a child <9 years of age without other congenital cardiac defects having died suddenly with this coronary anomaly. The transthoracic echocardiogram demonstrated normal origins of the coronary arteries, but on autopsy, an anomalous origin of the left main coronary artery from the right sinus of Valsalva was found. PMID:23880063

Bishnoi, Ram N; McMillan, Kristen N; Thompson, William R

2014-08-01

33

Lessons from patient-specific 3D models of the cardiac chambers after the Mustard operation  

PubMed Central

The recent ability to create detailed 3D models of the atrial and ventricular chambers using CT, MRI and rapid prototyping offers unique opportunities to study the size and shape of the different cardiac chambers both before and following operation for complex cardiac anomalies. We here describe the techniques for creating detailed 3D models of the heart and demonstrate the utility of these techniques in a patient studied after the Mustard operation. This can give important insights into the changes in size and shape of the different chambers and the patterns of blood flow from the pulmonary and systemic veins to the ‘appropriate’ ventricle. This information in turn could be extremely helpful in understanding and optimizing the overall hemodynamic function after the Mustard operation.

Chapron, Julien; Hosny, Hatem; Torii, Ryo; Sedky, Yasser; Donya, Mohamed; Yacoub, Magdi H

2013-01-01

34

Left ventricular systolic torsion correlates global cardiac performance during dyssynchrony and cardiac resynchronization therapy.  

PubMed

Left ventricular (LV) systolic torsion is a primary mechanism contributing to stroke volume (SV). We hypothesized that change in LV torsion parallels changes in global systolic performance during dyssynchrony and cardiac resynchronization therapy (CRT). Seven anesthetized open chest dogs had LV pressure-volume relationship. Apical, basal, and mid-LV cross-sectional echocardiographic images were studied by speckle tracking analysis. Right atrial (RA) pacing served as control. Right ventricular (RV) pacing simulated left bundle branch block. Simultaneous RV-LV free wall and RV-LV apex pacing (CRTfw and CRTa, respectively) modeled CRT. Dyssynchrony was defined as the time difference in peak strain between earliest and latest segments. Torsion was calculated as the maximum difference between the apical and basal rotation. RA pacing had minimal dyssynchrony (52 ± 36 ms). RV pacing induced dyssynchrony (189 ± 61 ms, P < 0.05). CRTa decreased dyssynchrony (46 ± 36 ms, P < 0.05 vs. RV pacing), whereas CRTfw did not (110 ± 96 ms). Torsion during baseline RA was 6.6 ± 3.7°. RV pacing decreased torsion (5.1 ± 3.6°, P < 0.05 vs. control), and reduced SV, stroke work (SW), and dP/dt(max) compared with RA (21 ± 5 vs. 17 ± 5 ml, 252 ± 61 vs. 151 ± 64 mJ, and 2,063 ± 456 vs. 1,603 ± 424 mmHg/s, respectively, P < 0.05). CRTa improved torsion, SV, SW, and dP/dt(max) compared with RV pacing (7.7 ± 4.7°, 23 ± 3 ml, 240 ± 50 mJ, and 1,947 ± 647 mmHg/s, respectively, P < 0.05), whereas CRTfw did not (5.1 ± 3.6°, 18 ± 5 ml, 175 ± 48 mJ, and 1,699 ± 432 mmHg/s, respectively, P < 0.05). LV torsion changes covaried across conditions with SW (y = 0.94x+12.27, r = 0.81, P < 0.0001) and SV (y = 0.66x+0.91, r = 0.81, P < 0.0001). LV dyssynchrony changes did not correlate with SW or SV (r = -0.12, P = 0.61 and r = 0.08, P = 0.73, respectively). Thus, we conclude that LV torsion is primarily altered by dyssynchrony, and CRT that restores LV performance also restores torsion. PMID:21169399

Lamia, Bouchra; Tanabe, Masaki; Tanaka, Hidekazu; Kim, Hyung Kook; Gorcsan, John; Pinsky, Michael R

2011-03-01

35

Left ventricular hypertrophy, cardiac remodeling and asymmetric dimethylarginine (ADMA) in hemodialysis patients  

Microsoft Academic Search

Left ventricular hypertrophy, cardiac remodeling and asymmetric dimethylarginine (ADMA) in hemodialysis patients.BackgroundThe endogenous inhibitor of nitric oxide (NO), asymmetric dimethylarginine (ADMA), is a strong predictor of adverse cardiovascular outcomes in patients with end-stage renal disease (ESRD).MethodsSince arterial and cardiac remodeling is associated with altered endothelial microcirculatory responses to forearm ischemia (a NO-dependent response), interference of ADMA with the NO system

Carmine Zoccali; Francesca Mallamaci; Renke Maas; Francesco A Benedetto; Giovanni Tripepi; Lorenzo S Malatino; Alessandro Cataliotti; Ignazio Bellanuova; Rainer Böger

2002-01-01

36

Capsule endoscopy in patients with cardiac pacemakers, implantable cardioverter defibrillators and left heart assist devices  

PubMed Central

According to the recommendations of the US Food and Drug Administration and manufacturers, capsule endoscopy should not be used in patients carrying implanted cardiac devices. For this review we considered studies indexed (until 30.06.2013) in Medline [keywords: capsule endoscopy, small bowel endoscopy, cardiac pacemaker, implantable cardioverter defibrillator, interference, left heart assist device], technical information from Given Imaging and one own publication (not listed in Medline). Several in vitro and in vivo studies included patients with implanted cardiac devices who underwent capsule endoscopy. No clinically relevant interference was noticed. Initial reports on interference with a simulating device were not reproduced. Furthermore technical data of PillCam (Given Imaging) demonstrate that the maximum transmission power is below the permitted limits for cardiac devices. Hence, impairment of cardiac pacemaker, defibrillator or left ventricular heart assist device function by capsule endoscopy is not expected. However, wireless telemetry can cause dysfunction of capsule endoscopy recording. Application of capsule endoscopy is feasible and safe in patients with implanted cardiac devices such as pacemakers, cardioverter defibrillators, and left heart assist devices. Development of new technologies warrants future re-evaluation.

Bandorski, Dirk; Holtgen, Reinhard; Stunder, Dominik; Keuchel, Martin

2014-01-01

37

Automatic functional analysis of left ventricle in cardiac cine MRI  

PubMed Central

Rationale and objectives A fully automated left ventricle segmentation method for the functional analysis of cine short axis (SAX) magnetic resonance (MR) images was developed, and its performance evaluated with 133 studies of subjects with diverse pathology: ischemic heart failure (n=34), non-ischemic heart failure (n=30), hypertrophy (n=32), and healthy (n=37). Materials and methods The proposed automatic method locates the left ventricle (LV), then for each image detects the contours of the endocardium, epicardium, papillary muscles and trabeculations. Manually and automatically determined contours and functional parameters were compared quantitatively. Results There was no significant difference between automatically and manually determined end systolic volume (ESV), end diastolic volume (EDV), ejection fraction (EF) and left ventricular mass (LVM) for each of the four groups (paired sample t-test, ?=0.05). The automatically determined functional parameters showed high correlations with those derived from manual contours, and the Bland-Altman analysis biases were small (1.51 mL, 1.69 mL, –0.02%, –0.66 g for ESV, EDV, EF and LVM, respectively). Conclusions The proposed technique automatically and rapidly detects endocardial, epicardial, papillary muscles’ and trabeculations’ contours providing accurate and reproducible quantitative MRI parameters, including LV mass and EF.

Lu, Ying-Li; Connelly, Kim A.; Dick, Alexander J.; Wright, Graham A.

2013-01-01

38

Real-time cardiac output estimation of the circulatory system under left ventricular assistance  

Microsoft Academic Search

A method for indirect and real-time estimation of the cardiac output of the circulatory system supported by the left ventricular assist device (LVAD) is proposed. This method has low invasiveness and is useful for clinical applications of the LVAD since it needs only two measurements: the rate of blood outflow from the LVAD and the aortic pressure. The method is

Makoto Yoshizawa; Hiroshi Takeda; Makoto Miura; Tomoyuki Yambe; Yoshiaki Katahira; Shin-ichi Nitta

1993-01-01

39

Left ventricular diastolic dysfunction of the cardiac surgery patient; a point of view for the cardiac surgeon and cardio-anesthesiologist  

Microsoft Academic Search

BACKGROUND: Left ventricular diastolic dysfunction (DD) is defined as the inability of the ventricle to fill to a normal end-diastolic volume, both during exercise as well as at rest, while left atrial pressure does not exceed 12 mm Hg. We examined the concept of left ventricular diastolic dysfunction in a cardiac surgery setting. MATERIALS AND METHODS: Literature review was carried

Efstratios E Apostolakis; Nikolaos G Baikoussis; Haralabos Parissis; Stavros N Siminelakis; Georgios S Papadopoulos

2009-01-01

40

Cardiac phase-targeted dynamic load on left ventricle differentially regulates phase-sensitive gene expressions and pathway activation.  

PubMed

The heart has remarkable capacity to adapt to mechanical load and to dramatically change its phenotype. The mechanism underlying such diverse phenotypic adaptations remains unknown. Since systolic overload induces wall thickening, while diastolic overload induces chamber enlargement, we hypothesized that cardiac phase-sensitive mechanisms govern the adaptation. We inserted a balloon into the left ventricle (LV) of a Langendorff perfused rat heart, and controlled LV volume (LVV) using a high performance servo-pump. We created isolated phasic systolic overload (SO) by isovolumic contraction (peak LV pressure >170mmHg) at unstressed diastolic LVV [end-diastolic pressure (EDP)=0mmHg]. We also created pure phasic diastolic overload (DO) by increasing diastolic LVV until EDP >40mmHg and unloading completely in systole. After 3hours under each condition, the myocardium was analyzed using DNA microarray. Gene expressions under SO and DO conditions were compared against unloaded control condition using gene ontology and pathway analysis (n=4 each). SO upregulated proliferation-related genes, whereas DO upregulated fibrosis-related genes (P<10(-5)). Both SO and DO upregulated genes related functionally to cardiac hypertrophy, although the gene profiles were totally different. Upstream regulators confirmed by Western blot indicated that SO activated extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase, and Ca(2+)/calmodulin-dependent protein kinase II (3.2-, 2.0-, and 4.7-fold versus control, P<0.05, n=5), whereas DO activated p38 (2.9-fold, P<0.01), which was consistent with the downstream gene expressions. In conclusion, pure isolated systolic and diastolic overload permits elucidation of cardiac phase-sensitive gene regulation. The genomic responses indicate that mechanisms governing the cardiac phase-sensitive adaptations are different. PMID:24004468

Onitsuka, Ken; Ide, Tomomi; Arai, Shinobu; Hata, Yuko; Murayama, Yoshinori; Hosokawa, Kazuya; Sakamoto, Takafumi; Tobushi, Tomoyuki; Sakamoto, Kazuo; Fujino, Takeo; Sunagawa, Kenji

2013-11-01

41

Left Atrial Appendages from Adult Hearts Contain a Reservoir of Diverse Cardiac Progenitor Cells  

PubMed Central

Aims There is strong evidence supporting the claim that endogenous cardiac progenitor cells (CPCs) are key players in cardiac regeneration, but the anatomic source and phenotype of the master cardiac progenitors remains uncertain. Our aim was to investigate the different cardiac stem cell populations in the left atrial appendage (LAA) and their fates. Methods and Results We investigated the CPC content and profile of adult murine LAAs using immunohistochemistry and flow cytometry. We demonstrate that the LAA contains a large number of CPCs relative to other areas of the heart, representing over 20% of the total cell number. We grew two distinct CPC populations from the LAA by varying the degree of proteolysis. These differed by their histological location, surface marker profiles and growth dynamics. Specifically, CD45pos cells grew with milder proteolysis, while CD45neg cells grew mainly with more intense proteolysis. Both cell types could be induced to differentiate into cells with cardiomyocyte markers and organelles, albeit by different protocols. Many CD45pos cells expressed CD45 initially and rapidly lost its expression while differentiating. Conclusions Our results demonstrate that the left atrial appendage plays a role as a reservoir of multiple types of progenitor cells in murine adult hearts. Two different types of CPCs were isolated, differing in their epicardial-myocardial localization. Considering studies demonstrating layer-specific origins of different cardiac progenitor cells, our findings may shed light on possible pathways to study and utilize the diversity of endogenous progenitor cells in the adult heart.

Platt, Yardanna; Helman, Yaron; Feinberg, Yael; Lotan, Chaim; Beeri, Ronen

2013-01-01

42

Model-based localization of the left ventricle from cardiac MR scans  

NASA Astrophysics Data System (ADS)

A new approach for the extraction of the myocardium from MR cardiac scans is presented. Segmentation and recognition of the left ventricle by a sequence of generic image processing operations is carried out in an order determined by a model of domain-specific relational, spatial, and morphological knowledge of the cardiac images. In particular, a new technique for constrained surface deformation by variable morphological dilation is introduced. These methods, incorporated in a prototype system called CARDIAN, have produced encouraging results in initial experiments with MR scans from phantom, dog, and human studies.

Gong, Leiguang; Cui, Ting; Kulikowski, Casimir A.; Mezrich, Reuben S.

1993-07-01

43

Cardiac CT and MRI guide surgery in impending left ventricular rupture after acute myocardial infarction  

PubMed Central

We report the case of a 67 year-old patient who presented with worsening chest pain and shortness of breath, four days post acute myocardial infarction. Contrast enhanced computed tomography of the chest ruled out a pulmonary embolus but revealed an unexpected small subepicardial aneurysm (SEA) in the lateral left ventricular wall which was confirmed on cardiac magnetic resonance imaging. Intraoperative palpation of the left lateral wall was guided by the cardiac MRI and CT findings and confirmed the presence of focally thinned and weakened myocardium, covered by epicardial fat. An aneurysmorrhaphy was subsequently performed in addition to coronary bypass surgery and a mitral valve repair. The patient was discharged home on post operative day eight in good condition and is feeling well 2 years after surgery.

Vogel-Claussen, Jens; Skrok, Jan; Fishman, Elliot K; Lima, Joao AC; Shah, Ashish S; Bluemke, David A

2009-01-01

44

Medical management of connector pin thrombosis with the Amplatzer cardiac plug left atrial closure device  

PubMed Central

Transcatheter closure of the left atrial appendage with the Amplatzer™ cardiac plug device and double antiplatelet treatment for 3 mo has become an alternative treatment for patients with atrial fibrillation at high embolism risk and contraindications for chronic oral anticoagulation. The inadequate implantation of the left atrial appendage closure device and the discontinuation of double antiplatelet therapy are well-known as factors related to device thrombosis. Nevertheless, device thrombosis after adequate implantation requiring surgical treatment or restarting chronic oral anticoagulation has been reported and can reach 15% of patients. The connector pin thrombosis of the Amplatzer™ cardiac plug, despite a good adherence to antiplatelet treatment, has been recently described as a potential mechanism for device thrombosis. Our clinical case reports the management of this condition for the first time, showing that the early detection of thrombotic complications by transesophageal echocardiography permits solving this serious complication with medical treatment only.

Fernandez-Rodriguez, Diego; Vannini, Luca; Martin-Yuste, Victoria; Brugaletta, Salvatore; Robles, Rocio; Regueiro, Ander; Masotti, Monica; Sabate, Manel

2013-01-01

45

Retinoid signaling is required to complete the vertebrate cardiac left/right asymmetry pathway.  

PubMed

Vitamin A-deficient (VAD) quail embryos have severe abnormalities, including a high incidence of reversed cardiac situs. Using this model we examined in vivo the physiological function of vitamin A in the left/right (L/R) cardiac asymmetry pathway. Molecular analysis reveals the expression of early asymmetry genes activin receptor IIa, sonic hedgehog, Caronte, Lefty-1, and Fgf8 to be unaffected by the lack of retinoids, while expression of the downstream genes nodal-related, snail-related (cSnR), and Pitx2 is altered. In VAD embryos nodal expression in left lateral plate mesoderm (LPM) is severely downregulated and the expression domain altered during neurulation. Similarly, the expression of cSnR in the right LPM and of Pitx2 in the left side posterior heart-forming region (HFR) is downregulated in the VAD embryos. The lack of retinoids does not cause randomization or ectopic expression of nodal, cSnR, or Pitx2. At the six- to eight-somite stage nodal is expressed transiently in the left posterior HFR of normal quail embryos; this expression is missing in VAD embryos and may be linked to the loss of Pitx2 expression in this region of VAD quail embryos. Administration of retinoids to VAD embryos prior to the six-somite stage rescues the expression of nodal, cSnR, and Pitx2 as well as the randomized VAD cardiac phenotype. There is an absolute requirement for retinoids at the four- to five-somite developmental window for cardiogenesis and cardiac L/R specification to proceed normally. We conclude that retinoids do not regulate the left/right-specific sidedness assignments for expression of genes on the vertebrate cardiac asymmetry pathway, but are required during neurulation for the maintenance of adequate levels of their expression and for the development of the posterior heart tube and a loopable heart. Cardiac asymmetry may be but one of several critical events regulated by retinoid signaling in the retinoid-sensitive developmental window. PMID:10882519

Zile, M H; Kostetskii, I; Yuan, S; Kostetskaia, E; St Amand, T R; Chen, Y; Jiang, W

2000-07-15

46

Post-hypothermic cardiac left ventricular systolic dysfunction after rewarming in an intact pig model  

Microsoft Academic Search

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

Ole Magnus Filseth; Ole-Jakob How; Timofei Kondratiev; Tor Magne Gamst; Torkjel Tveita

2010-01-01

47

Left–right asymmetry and congenital cardiac defects: Getting to the heart of the matter in vertebrate left–right axis determination  

Microsoft Academic Search

Cellular and molecular left–right differences that are present in the mesodermal heart fields suggest that the heart is lateralized from its inception. Left–right asymmetry persists as the heart fields coalesce to form the primary heart tube, and overt, morphological asymmetry first becomes evident when the heart tube undergoes looping morphogenesis. Thereafter, chamber formation, differentiation of the inflow and outflow tracts,

Ann F. Ramsdell

2005-01-01

48

The quest for load-independent left ventricular chamber properties: Exploring the normalized pressure phase plane  

PubMed Central

The pressure phase plane (PPP), defined by dP(t)/dt versus P(t) coordinates has revealed novel physiologic relationships not readily obtainable from conventional, time domain analysis of left ventricular pressure (LVP). We extend the methodology by introducing the normalized pressure phase plane (nPPP), defined by 0 ? P ? 1 and ?1 ? dP/dt ? +1. Normalization eliminates load-dependent effects facilitating comparison of conserved features of nPPP loops. Hence, insight into load-invariant systolic and diastolic chamber properties and their coupling to load can be obtained. To demonstrate utility, high-fidelity P(t) data from 14 subjects (4234 beats) was analyzed. PNR, the nPPP (dimensionless) pressure, where –dP/dtpeak occurs, was 0.61 and had limited variance (7%). The relative load independence of PNR was corroborated by comparison of PPP and nPPP features of normal sinus rhythm (NSR) and (ejecting and nonejecting) premature ventricular contraction (PVC) beats. PVCs had lower P(t)max and lower peak negative and positive dP(t)/dt values versus NSR beats. In the nPPP, +dP/dtpeak occurred at higher (dimensionless) P in PVC beats than in regular beats (0.44 in NSR vs. 0.48 in PVC). However, PNR for PVC versus NSR remained unaltered (PNR = 0.64; P > 0.05). Possible mechanistic explanation includes a (near) load-independent (constant) ratio of maximum cross-bridge uncoupling rate to instantaneous wall stress. Hence, nPPP analysis reveals LV properties obscured by load and by conventional temporal P(t) and dP(t)/dt analysis. nPPP identifies chamber properties deserving molecular and cellular physiologic explanation.

Ghosh, Erina; Kovacs, Sandor J

2013-01-01

49

The effects of cardiac infarction on realistic three-dimensional left ventricular blood ejection.  

PubMed

The effect of cardiac infarction on the flow patterns in cardiac left ventricular ejection was studied using a realistic model which was made from the profile of the left ventricle of a dog heart in diastole. A coordinate measuring machine was used to measure the left ventricular coordinates, and these were input into a three-dimensional flow simulation package. The left ventricular wall motion was described by having the walls moved towards the center of the aortic outlet, and in the case of infarcted tissue, the ventricular wall movement was diminished to simulate infarction flow behavior. The final ventricular volume varied from 25 percent to 54.1 percent of the initial volume in cases without and with infarction, respectively. The maximum blood ejection velocities and ventricular pressure decreased significantly in the presence of infarction. Infarcted areas showed complex blood flow vortex formation not present in the healthy ventricles. The computational technique presented here predicts infarction flow effects which could be observed with measurement techniques such as ultrasound and magnetic resonance imaging, allowing a finer detail of understanding than using either simulation or experimental measurements alone. PMID:8833081

Taylor, T W; Suga, H; Goto, Y; Okino, H; Yamaguchi, T

1996-02-01

50

Toward standardized mapping for left atrial analysis and cardiac ablation guidance  

NASA Astrophysics Data System (ADS)

In catheter-based cardiac ablation, the pulmonary vein ostia are important landmarks for guiding the ablation procedure, and for this reason, have been the focus of many studies quantifying their size, structure, and variability. Analysis of pulmonary vein structure, however, has been limited by the lack of a standardized reference space for population based studies. Standardized maps are important tools for characterizing anatomic variability across subjects with the goal of separating normal inter-subject variability from abnormal variability associated with disease. In this work, we describe a novel technique for computing flat maps of left atrial anatomy in a standardized space. A flat map of left atrial anatomy is created by casting a single ray through the volume and systematically rotating the camera viewpoint to obtain the entire field of view. The technique is validated by assessing preservation of relative surface areas and distances between the original 3D geometry and the flat map geometry. The proposed methodology is demonstrated on 10 subjects which are subsequently combined to form a probabilistic map of anatomic location for each of the pulmonary vein ostia and the boundary of the left atrial appendage. The probabilistic map demonstrates that the location of the inferior ostia have higher variability than the superior ostia and the variability of the left atrial appendage is similar to the superior pulmonary veins. This technique could also have potential application in mapping electrophysiology data, radio-frequency ablation burns, or treatment planning in cardiac ablation therapy.

Rettmann, M. E.; Holmes, D. R.; Linte, C. A.; Packer, D. L.; Robb, R. A.

2014-03-01

51

Left ventricular dysfunction is a risk factor for sudden cardiac death in adults late after repair of tetralogy of fallot  

Microsoft Academic Search

ObjectivesThe purpose of this study was to determine if left ventricular (LV) systolic dysfunction was also a predictor of sudden cardiac death (SCD) in adults late after repair of tetralogy of Fallot (TOF).

Akash Ghai; Candice Silversides; Louise Harris; Gary D. Webb; Samuel C. Siu; Judith Therrien

2002-01-01

52

Tissue doppler imaging predicts improved systolic performance and reversed left ventricular remodeling during long-term cardiac resynchronization therapy  

Microsoft Academic Search

ObjectivesWe sought to evaluate the long-term impact of cardiac resynchronization therapy (CRT) on left ventricular (LV) performance and remodeling using three-dimensional echocardiography and tissue Doppler imaging (TDI).

Peter Søgaard; Henrik Egeblad; W. Yong Kim; Henrik K. Jensen; Anders K. Pedersen; Bent Ø. Kristensen; Peter T. Mortensen

2002-01-01

53

Plasma cardiac natriuretic peptide determination as a screening test for the detection of patients with mild left ventricular impairment  

Microsoft Academic Search

OBJECTIVE: To determine the usefulness of measuring the cardiac natriuretic peptides, atrial natriuretic factor, N-terminal pro-atrial natriuretic factor, and brain natriuretic peptide, as screening tests for identifying patients with mild left ventricular impairment. DESIGN: Cross-sectional evaluation of the diagnostic accuracy of the cardiac natriuretic peptides. SETTING: Cardiac catheterisation unit, Norwegian central hospital. PATIENTS: A consecutive series of 254 patients undergoing

T. Omland; A. Aakvaag; H. Vik-Mo

1996-01-01

54

Morphology and significance of the left ventricular collagen network in young patients with hypertrophic cardiomyopathy and sudden cardiac death  

Microsoft Academic Search

BACKGROUNDHypertrophic cardiomyopathy (HCM) is a primary cardiac disease with a diverse clinical spectrum, in which many of the abnormal structural and pathophysiologic features are consequences of inappropriate left ventricular hypertrophy.METHODSWe analyzed the amount, distribution and structure of the cardiac collagen network in transmural sections of the ventricular septum (thickness 17 to 40 mm, mean 25 mm) in 16 previously asymptomatic

Jamshid Shirani; Ruth Pick; William C Roberts; Barry J Maron

2000-01-01

55

Left Ventricular Structure and Function by Cardiac Magnetic Resonance Imaging in Rheumatoid Arthritis  

PubMed Central

Background Heart failure is a major contributor to cardiovascular morbidity and mortality in rheumatoid arthritis. However, little is known about myocardial structure and function in this population. Methods Using cardiac magnetic resonance imaging, measures of myocardial structure and function were assessed in men and women with rheumatoid arthritis enrolled in ESCAPE RA, a cohort study of subclinical cardiovascular disease in rheumatoid arthritis, and compared with controls without rheumatoid arthritis enrolled in the Baltimore cohort of the Multi-Ethnic Study of Atherosclerosis. Results Myocardial measures were compared between 75 rheumatoid arthritis patients and 225 matched controls. After adjustment, mean left-ventricular mass was 26 grams lower for the RA group compared to controls (p<0.001), an 18% difference. After similar adjustment, mean left-ventricular ejection fraction, cardiac output, and stroke volume were modestly lower in the rheumatoid arthritis group vs. controls. Mean left-ventricular end-systolic and end-diastolic volumes did not differ by rheumatoid arthritis status. Within the rheumatoid arthritis group, higher levels of anti-CCP antibodies and current use of biologics, but not other disease activity or severity measures, were associated with significantly lower adjusted mean left-ventricular mass, end-diastolic volume, and stroke volume, but not ejection fraction. The combined associations of anti-CCP antibody level and biologic use on myocardial measures were additive, without evidence of interaction. Conclusions These findings suggest that the progression to heart failure in RA may occur through reduced myocardial mass rather than hypertrophy. Both modifiable and non-modifiable factors may contribute to lower levels of left-ventricular mass and volume.

Giles, Jon T.; Malayeri, Ashkan A.; Fernandes, Veronica; Post, Wendy; Blumenthal, Roger S.; Bluemke, David; Vogel-Claussen, Jens; Szklo, Moyses; Petri, Michelle; Gelber, Allan C.; Brumback, Lyndia; Lima, Joao; Bathon, Joan M.

2010-01-01

56

Link Between Change in Cognition and Left Ventricular Function following Cardiac Resynchronization Therapy  

PubMed Central

PURPOSE In patients with heart failure, reduced cardiac ejection fraction has been associated with impaired cognition. Improving cardiac function may have beneficial effects on cognition; however, no controlled intervention studies have examined this possibility. Cardiac resynchronization therapy (CRT) is 1 intervention that has been shown to increase cardiac function. The goals of the current study were to: 1) evaluate neuropsychological performance before and 3-months after CRT and 2) examine follow-up neuropsychological performance of patients classified based on extent of improved left ventricular ejection fraction (LVEF). METHODS Twenty-seven patients with moderate to severe heart failure completed a neuropsychological assessment, 6-minute walk test, and transthoracic echocardiogram prior to and 3-months post-CRT. Patients were classified based on improvement in LVEF. Results of a MANOVA revealed a significant effect of improvement in LVEF on change in cognition (Wilk’s lambda, P=.031). RESULTS Patients with improved LVEF demonstrated significant increases on measures of executive functioning (F=8.57, P=.007) and visuospatial function (F=7.52, P=.011) and less decline on global cognition (F=5.73, P=.024) than those without LVEF improvement. CONCLUSIONS Findings provide preliminary evidence that improved LVEF in response to CRT is associated with enhanced cognitive outcomes within 3 months of CRT. Patients with improved LVEF showed better outcomes on measures of executive functioning, global cognition, and visuospatial functioning. Future controlled large scale trials will be necessary to determine whether there is an underlying causal relationship linking increase in LVEF and cognition.

Hoth, Karin F.; Poppas, Athena; Ellison, Kristin E.; Paul, Robert H.; Sokobin, Andrew; Cho, Youngsoo; Cohen, Ronald A.

2010-01-01

57

Transient cardiac arrest in patient with left ventricular noncompaction (spongiform cardiomyopathy).  

PubMed

Left ventricular noncompaction (LVNC), also known as spongiform cardiomyopathy, is a severe disease that has not previously been discussed with respect to general anesthesia. We treated a child with LVNC who experienced cardiac arrest. Dental treatment under general anesthesia was scheduled because the patient had a risk of endocarditis due to dental caries along with a history of being uncooperative for dental care. During sevoflurane induction, severe hypotension and laryngospasm resulted in cardiac arrest. Basic life support (cardiopulmonary resuscitation) was initiated to resuscitate the child, and his cardiorespiratory condition improved. Thereafter, an opioid-based anesthetic was performed, and recovery was smooth. In LVNC, opioid-based anesthesia is suggested to avoid the significant cardiac suppression seen with a volatile anesthetic, once intravenous access is established. Additionally, all operating room staff should master Advanced Cardiac Life Support/Pediatric Advanced Life Support (including intraosseous access), and more than 1 anesthesiologist should be present to induce general anesthesia, if possible, for this high-risk patient. PMID:21410361

Yamazaki, Shinya; Ito, Hiroshi; Kawaai, Hiroyoshi

2011-01-01

58

Transient Cardiac Arrest in Patient With Left Ventricular Noncompaction (Spongiform Cardiomyopathy)  

PubMed Central

Left ventricular noncompaction (LVNC), also known as spongiform cardiomyopathy, is a severe disease that has not previously been discussed with respect to general anesthesia. We treated a child with LVNC who experienced cardiac arrest. Dental treatment under general anesthesia was scheduled because the patient had a risk of endocarditis due to dental caries along with a history of being uncooperative for dental care. During sevoflurane induction, severe hypotension and laryngospasm resulted in cardiac arrest. Basic life support (cardiopulmonary resuscitation) was initiated to resuscitate the child, and his cardiorespiratory condition improved. Thereafter, an opioid?based anesthetic was performed, and recovery was smooth. In LVNC, opioid?based anesthesia is suggested to avoid the significant cardiac suppression seen with a volatile anesthetic, once intravenous access is established. Additionally, all operating room staff should master Advanced Cardiac Life Support/Pediatric Advanced Life Support (including intraosseous access), and more than 1 anesthesiologist should be present to induce general anesthesia, if possible, for this high?risk patient.

Yamazaki, Shinya; Ito, Hiroshi; Kawaai, Hiroyoshi

2011-01-01

59

Left ventricular thrombus mimicking primary cardiac tumor in a patient with primary antiphospholipid syndrome and recurrent systemic embolism  

Microsoft Academic Search

Primary antiphospholipid syndrome (APS) is a well-defined entity characterized by spontane- ous and recurrent abortion, thrombocytopenia and recurrent vascular thromboses (arterial and venous). Left ventricular thrombus mimicking primary cardiac tumor with recurrent systemic embolism has not been previously reported. In this report we describe a 39 year-old man admitted to hospital presenting with left hemi- paresis and a peripheral embolism.

F. Cianciulli; Jorge A. Lax; Roberto O. Neme; Sebastian Fandino Lound; Coloma E. Parisi; Horacio A. Prezioso; Luis A. Vidal

60

Cardiac embolism after implantable cardiac defibrillator shock in non-anticoagulated atrial fibrillation: The role of left atrial appendage occlusion.  

PubMed

Cardioembolic events are one of the most feared complications in patients with non-valvular atrial fibrillation (NVAF) and a formal contraindication to oral anticoagulation (OAC). The present case report describes a case of massive peripheral embolism after an implantable cardiac defibrillator (ICD) shock in a patient with NVAF and a formal contraindication to OAC due to previous intracranial hemorrhage. In order to reduce the risk of future cardioembolic events, the patient underwent percutaneous left atrial appendage (LAA) occlusion. A 25 mm Amplatzer™ Amulet was implanted and the patient was discharged the following day without complications. The potential risk of thrombus dislodgement after an electrical shock in patients with NVAF and no anticoagulation constitutes a particular scenario that might be associated with an additional cardioembolic risk. Although LAA occlusion is a relatively new technique, its usage is rapidly expanding worldwide and constitutes a very valid alternative for patients with NVAF and a formal contraindication to OAC. PMID:24772261

Freixa, Xavier; Andrea, Rut; Martín-Yuste, Victoria; Fernández-Rodríguez, Diego; Brugaletta, Salvatore; Masotti, Mónica; Sabaté, Manel

2014-04-26

61

Cardiac embolism after implantable cardiac defibrillator shock in non-anticoagulated atrial fibrillation: The role of left atrial appendage occlusion  

PubMed Central

Cardioembolic events are one of the most feared complications in patients with non-valvular atrial fibrillation (NVAF) and a formal contraindication to oral anticoagulation (OAC). The present case report describes a case of massive peripheral embolism after an implantable cardiac defibrillator (ICD) shock in a patient with NVAF and a formal contraindication to OAC due to previous intracranial hemorrhage. In order to reduce the risk of future cardioembolic events, the patient underwent percutaneous left atrial appendage (LAA) occlusion. A 25 mm Amplatzer™ Amulet was implanted and the patient was discharged the following day without complications. The potential risk of thrombus dislodgement after an electrical shock in patients with NVAF and no anticoagulation constitutes a particular scenario that might be associated with an additional cardioembolic risk. Although LAA occlusion is a relatively new technique, its usage is rapidly expanding worldwide and constitutes a very valid alternative for patients with NVAF and a formal contraindication to OAC.

Freixa, Xavier; Andrea, Rut; Martin-Yuste, Victoria; Fernandez-Rodriguez, Diego; Brugaletta, Salvatore; Masotti, Monica; Sabate, Manel

2014-01-01

62

Variants of Folate Metabolism Genes and Risk of Left-Sided Cardiac Defects  

PubMed Central

Background Congenital heart defects (CHD) are the most common, serious group of birth defects. Although relatively little is known about the causes of these conditions and there are no established prevention strategies, evidence suggests that the risk of CHD may be related to maternal folate status as well as genetic variants in folate-related genes. Efforts to establish the relationships between these factors and CHD risk have, however, been hampered by a number of factors, including small study sample sizes and phenotypic heterogeneity. Methods The present study examined the relationship between nine genetic variants in eight folate-related genes and a relatively homogeneous group of left-sided cardiac defects in a cohort of 386 case-parent triads. Log-linear analyses were used to assess both maternal and inherited genetic effects. Results Analyses of the study data provided marginal evidence that the maternal MTR A2756G (unadjusted p=0.01) and the inherited BHMT G742A genotypes (unadjusted p=0.06) influence the risk of this subset of CHD. However, neither association achieved significance when the false-discovery rate was controlled at 0.05. Conclusions These results, which are based on the largest study sample and most comprehensive assessment of the relationship between left-sided cardiac defects and folate-related genes reported to date, provide little evidence that this subset of CHD is folate-related. However, even larger studies and more comprehensive evaluations of the folate pathway genes are required to fully explore the relationship between folate and left-sided cardiac defects.

Mitchell, Laura E.; Long, Jin; Garbarini, Jennifer; Paluru, Prasuna; Goldmuntz, Elizabeth

2010-01-01

63

Human cardiac tissue in a microperfusion chamber simulating extracorporeal circulation - ischemia and apoptosis studies  

PubMed Central

Background After coronary artery bypass grafting ischemia/reperfusion injury inducing cardiomyocyte apoptosis may occur. This surgery-related inflammatory reaction appears to be of extreme complexity with regard to its molecular, cellular and tissue mechanisms and many studies have been performed on animal models. However, finding retrieved from animal studies were only partially confirmed in humans. To investigate this phenomenon and to evaluate possible therapies in vitro, adequate human cardiomyocyte models are required. We established a tissue model of human cardiomyocytes preserving the complex tissue environment. To our knowledge human cardiac tissue has not been investigated in an experimental setup mimicking extracorporeal circulation just in accordance to clinical routine, yet. Methods Cardiac biopsies were retrieved from the right auricle of patients undergoing elective coronary artery bypass grafting before cardiopulmonary bypass. The extracorporeal circulation was simulated by submitting the biopsies to varied conditions simulating cardioplegia (cp) and reperfusion (rep) in a microperfusion chamber. Cp/rep time sets were 20/7, 40/13 and 60/20 min. For analyses of the calcium homoeostasis the fluorescent calcium ion indicator FURA-2 and for apoptosis detection PARP-1 cleavage immunostaining were employed. Further the anti-apoptotic effect of carvedilol [10 ?M] was investigated by adding into the perfusate. Results Viable cardiomyocytes presented an intact calcium homoeostasis under physiologic conditions. Following cardioplegia and reperfusion a time-dependent elevation of cytosolic calcium as a sign of disarrangement of the calcium homoeostasis occurred. PARP-1 cleavage also showed a time-dependence whereas reperfusion had the highest impact on apoptosis. Cardioplegia and carvedilol could reduce apoptosis significantly, lowering it between 60-70% (p < 0.05). Conclusions Our human cardiac preparation served as a reliable cellular model tool to study apoptosis in vitro. Decisively cardiac tissue from the right auricle can be easily obtained at nearly every cardiac operation avoiding biopsying of the myocardium or even experiments on animals. The apoptotic damage induced by the ischemia/reperfusion stimulus could be significantly reduced by the cold crystalloid cardioplegia. The additional treatment of cardiomyocytes with a non-selective ?-blocker, carvedilol had even a significantly higher reduction of apoptotis.

2010-01-01

64

Pharmacologic cardiac resynchronization of a 1-year-old boy with severe left ventricular dysfunction.  

PubMed

Postero-septal accessory pathways (AP) are a rare cause of intraventricular dyssynchrony and severe LV dysfunction in children. Beside the common treatment with radiofrequency ablation of septal substrates we present the case of a successful pharmacologic resynchronization in a 13/12 years old male toddler with Wolff-Parkinson-White syndrome (WPW) and severe LV dysfunction (left ventricular biplane EF of 31 %) due to intraventricular dyssynchrony with septal to posterior wall motion delay (SPWMD) of 350 ms. Interventricular mechanical delay (IVMD) was 65 ms. Using propafenone, pharmacologic cardiac resynchronization could be achieved. Pharmacologic resynchronization should be considered as safe and effective alternative to catheter ablation in very young children. PMID:22484822

Paech, Christian; Flosdorff, Patrick; Gebauer, Roman Antonin

2012-10-01

65

Cardiac Output Derived From Left Ventricular Pressure During Conductance Catheter Evaluations: An Extended Modelflow Method  

Microsoft Academic Search

Objective  The Modelflow method computes cardiac output (CO) from arterial pressure (CO-MFao) by simulating a non-linear three-element\\u000a Windkessel model of aortic input impedance. We present a novel technique to apply the Modelflow method to the left ventricular\\u000a pressure (Plv) signal, to obtain an estimation of CO (CO-MFlv).\\u000a \\u000a \\u000a \\u000a Methods  We extended the model by simulating the aortic valve as a resistance placed in

Sergio Valsecchi; Giovanni B. Perego; Jan J. Schreuder; Federica Censi; Jos R. C. Jansen

2007-01-01

66

Sinus Node Dysfunction as the First Manifestation of Left Ventricular Noncompaction with Multiple Cardiac Abnormalities  

PubMed Central

Left ventricular noncompaction (LVNC) is a genetically heterogenous form of cardiomyopathy which may remain undiagnosed till adulthood due to the late presentation of typical symptoms such as dyspnea, congestion, ventricular arrhythmias and thromboembolism. Symptomatic bradycardia secondary to persistent sinus node dysfunction is very rare. Coexistent cardiac defects are common in children however in adults the disease is usually in isolated form. Here, we present a case of twenty-three year-old female LVNC patient with patent ductus arteriosus, bicuspid aortic valve and persistent sinus node dysfunction who presented with dizziness as the first manifestation of the disease.

Gungor, Baris; Alper, Ahmet T; Celebi, Ahmet; Bolca, Osman

2013-01-01

67

A collaborative resource to build consensus for automated left ventricular segmentation of cardiac MR images.  

PubMed

A collaborative framework was initiated to establish a community resource of ground truth segmentations from cardiac MRI. Multi-site, multi-vendor cardiac MRI datasets comprising 95 patients (73 men, 22 women; mean age 62.73±11.24years) with coronary artery disease and prior myocardial infarction, were randomly selected from data made available by the Cardiac Atlas Project (Fonseca et al., 2011). Three semi- and two fully-automated raters segmented the left ventricular myocardium from short-axis cardiac MR images as part of a challenge introduced at the STACOM 2011 MICCAI workshop (Suinesiaputra et al., 2012). Consensus myocardium images were generated based on the Expectation-Maximization principle implemented by the STAPLE algorithm (Warfield et al., 2004). The mean sensitivity, specificity, positive predictive and negative predictive values ranged between 0.63 and 0.85, 0.60 and 0.98, 0.56 and 0.94, and 0.83 and 0.92, respectively, against the STAPLE consensus. Spatial and temporal agreement varied in different amounts for each rater. STAPLE produced high quality consensus images if the region of interest was limited to the area of discrepancy between raters. To maintain the quality of the consensus, an objective measure based on the candidate automated rater performance distribution is proposed. The consensus segmentation based on a combination of manual and automated raters were more consistent than any particular rater, even those with manual input. The consensus is expected to improve with the addition of new automated contributions. This resource is open for future contributions, and is available as a test bed for the evaluation of new segmentation algorithms, through the Cardiac Atlas Project (www.cardiacatlas.org). PMID:24091241

Suinesiaputra, Avan; Cowan, Brett R; Al-Agamy, Ahmed O; Elattar, Mustafa A; Ayache, Nicholas; Fahmy, Ahmed S; Khalifa, Ayman M; Medrano-Gracia, Pau; Jolly, Marie-Pierre; Kadish, Alan H; Lee, Daniel C; Margeta, Ján; Warfield, Simon K; Young, Alistair A

2014-01-01

68

Regional assessment of cardiac left ventricular myocardial function via MRI statistical features.  

PubMed

Automating the detection and localization of segmental (regional) left ventricle (LV) abnormalities in magnetic resonance imaging (MRI) has recently sparked an impressive research effort, with promising performances and a breadth of techniques. However, despite such an effort, the problem is still acknowledged to be challenging, with much room for improvements in regard to accuracy. Furthermore, most of the existing techniques are labor intensive, requiring delineations of the endo- and/or epi-cardial boundaries in all frames of a cardiac sequence. The purpose of this study is to investigate a real-time machine-learning approach which uses some image features that can be easily computed, but that nevertheless correlate well with the segmental cardiac function. Starting from a minimum user input in only one frame in a subject dataset, we build for all the regional segments and all subsequent frames a set of statistical MRI features based on a measure of similarity between distributions. We demonstrate that, over a cardiac cycle, the statistical features are related to the proportion of blood within each segment. Therefore, they can characterize segmental contraction without the need for delineating the LV boundaries in all the frames. We first seek the optimal direction along which the proposed image features are most descriptive via a linear discriminant analysis. Then, using the results as inputs to a linear support vector machine classifier, we obtain an abnormality assessment of each of the standard cardiac segments in real-time. We report a comprehensive experimental evaluation of the proposed algorithm over 928 cardiac segments obtained from 58 subjects. Compared against ground-truth evaluations by experienced radiologists, the proposed algorithm performed competitively, with an overall classification accuracy of 86.09% and a kappa measure of 0.73. PMID:24184708

Afshin, Mariam; Ben Ayed, Ismail; Punithakumar, Kumaradevan; Law, Max; Islam, Ali; Goela, Aashish; Peters, Terry; Shuo Li

2014-02-01

69

Improved noninvasive method for measurement of cardiac output and evaluation of left-sided cardiac valve incompetence  

SciTech Connect

A time-saving method was developed to label red blood cells in vitro with /sup 99m/Tc while avoiding centrifugation. After tin incubation, extracellular tin was oxidized by sodium hypochlorite, and EDTA was added for stabilizing the complex prior to /sup 99m/Tc incubation. Labeling yields were 95%, and in vivo decay showed a high stability with a mean biologic half-life of eleven hours. The first-passage radionuclide technique for determination of cardiac output using the above-mentioned tracer was evaluated by using the left ventricle as area-of-interest with individual background correction after complete mixing of the tracer. This technique showed a high level of agreement with invasive methods. By combining this method for measurement of the forward stroke volume with the multigated equilibrium principle for determination of the total left ventricular stroke volume using similar background corrections, an exact evaluation of regurgitation fractions was obtained. In patients with aortic and mitral valve disease the noninvasive radionuclide technique gave similar but probably more accurate results as compared with contrast aortography and ventriculography. The radionuclide technique may be suitable for monitoring and selecting patients for surgical treatment.

Kelbaek, H.

1989-05-01

70

Localization and segmentation of left ventricle in cardiac cine-MR images.  

PubMed

Accurate delineation of the left ventricular myocardial boundaries on cardiac cine magnetic resonance (MR) images is essential for volumetric and functional cardiac analysis. Automated myocardial contour delineation often suffers from misalignment of slices, nonuniform coil sensitivity, blood-flow-related inter- and intraslice intensity inhomogeneities, blurring due to motion, partial voluming, and a need to circumscribe the papillary muscles and the trabeculae. In this paper, we propose a novel method for data-driven localization and segmentation of the left ventricle in the cine-MR images toward automated computation of ejection fraction (EF). Our hybrid segmentation method combines intensity- and texture-based fuzzy affinity maps obtained from a novel multiclass, multifeature fuzzy connectedness method with dynamic-programming-based boundary detection to delineate the myocardial contours. Bland-Altman analysis indicates that the mean biases of the end-diastolic volume, end-systolic volume, and EF estimates of our method are comparable to the interobserver variability when compared with the annotations from two experts. PMID:19473931

Kurkure, Uday; Pednekar, Amol; Muthupillai, Raja; Flamm, Scott D; Kakadiaris Ast, Ioannis A

2009-05-01

71

Continuous monitoring of cardiac rhythms in left ventricular assist device patients.  

PubMed

Monitoring of cardiac rhythms is of major importance in the treatment of heart failure patients with left ventricular assist devices (LVADs) implanted. A continuous surveillance of these rhythms could improve out-of-hospital care in these patients. The aim of this study was to investigate cardiac rhythms using available pump data only. Datasets (n = 141) obtained in the normal ward, in the intensive care unit, and during bicycle ergometry were analyzed in 11 recipients of a continuous flow LVAD (59.1 ± 9.7 years; male 82%). Tachograms and arrhythmic patterns derived from the pump flow waveform, and a simultaneously recorded ECG were compared, as well as heart rate variability parameters such as: the average heart beat duration (RR interval), the standard deviation of the beat duration (SDNN), the root-mean-square of the difference of successive beat durations (RMSSD), and the number of pairs of adjacent beat duration differing by >50 ms divided by the number of all beats (pNN50). A very good agreement of cardiac rhythm parameters from the pump flow compared with ECG was found. Tachycardia, atrial fibrillation, and extrasystoles could be accurately identified from the tachograms derived from the pump flow. Also, Bland-Altman analysis comparing pump flow with ECG indicated a very small difference in average RR interval of 0.3 ± 1.0 ms, in SSDN of 0.5 ± 2.7 ms, in RMSSD of 1.0 ± 5.6 ms, and in pNN50 of 0.3 ± 1.0%. Continuous monitoring of cardiac rhythms from available pump data is possible. It has the potential to reduce the out-of-hospital diagnostic burden and to permit a more efficient adjustment of the level of mechanical support. PMID:23902542

Moscato, Francesco; Granegger, Marcus; Edelmayer, Michael; Zimpfer, Daniel; Schima, Heinrich

2014-03-01

72

Comparison of Acute Alterations in Left Ventricular Relaxation and Diastolic Chamber Stiffness Induced by Hypoxia and Ischemia  

PubMed Central

To clarify conflicting reports concerning the effects of ischemia on left ventricular chamber stiffness, we compared the effects of hypoxia at constant coronary perfusion with those of global ischemia on left ventricular diastolic chamber stiffness using isolated, perfused rabbit hearts in which the left ventricle was contracting isovolumically. Since chamber volume was held constant, increases in left ventricular end diastolic pressure (LVEDP) reflected increases in chamber stiffness. At a control coronary flow rate (30 ml/min), 2 min of hypoxia and pacing tachycardia (4.0 Hz) produced major increases in postpacing LVEDP (10±1 to 24±3 mm Hg, P < 0.01) and the relaxation time constant, T, (40±4 to 224±37 ms, P < 0.001), while percent lactate extraction ratio became negative (+ 18±2 to ?48±15%, P < 0.001). Coronary perfusion pressure decreased (72±5 to 52±3 mm Hg, P < 0.01), and since coronary flow was held constant, the fall in coronary perfusion pressure reflected coronary dilation and a decrease in coronary vascular resistance. Following an average of 71±6s reoxygenation and initial heart rate (2.0 Hz), LVEDP and relaxation time constant T returned to control. Hypoxia alone (without pacing tachycardia) produced similar although less marked changes (LVEDP, 10±1 to 20±3 mm Hg; and T, 32±3 to 119±22 ms; P < 0.01 for both) and there was a strong correlation between LVEDP and T (r = 0.82, P < 0.001). When a similar degree of coronary vasodilatation was induced with adenosine, no change in LVEDP occurred, indicating that the increase in end diastolic pressure observed during hypoxia was not secondary to vascular engorgement, but due to an acute effect of hypoxia on the diastolic behavior of the ventricular myocardium. In contrast, global ischemia produced by low coronary flow (12?15 ml/min) resulted in a decrease in LVEDP, as well as a marked fall in left ventricular systolic pressure. In 14 global ischemia experiments, pacing tachycardia led to a further decline in left ventricular systolic pressure, and no increase was noted in postpacing LVEDP. Changes in lactate extraction ratio were much smaller in magnitude than with hypoxia and constant coronary perfusion. In two experiments (one at normal coronary flow and one at 15 ml/min), left ventricular systolic pressure did not change markedly from control when tachycardia was superimposed, and postpacing LVEDP showed a marked rise (to > 25 mm Hg), which gradually recovered over 1?2 min at the control heart rate. From these results, we conclude that left ventricular chamber stiffness increases when myocardial O2 demand exceeds supply. This change is usually masked in ischemic (reduced coronary flow) preparations, perhaps because of reduced turgor of the coronary vascular bed, marked reductions in systolic work (and therefore myocardial O2 requirements), and local accumulation of hydrogen ion and metabolites following acute severe reduction of coronary flow. The increased chamber stiffness during hypoxia is accompanied by marked slowing of relaxation, with increased diastolic pressure relative to volume persisting throughout diastole.

Serizawa, Takashi; Vogel, W. Mark; Apstein, Carl S.; Grossman, William

1981-01-01

73

Surgical removal of right-to-left cardiac shunt in the American alligator (Alligator mississippiensis) causes ventricular enlargement but does not alter apnoea or metabolism during diving  

PubMed Central

SUMMARY Crocodilians have complete anatomical separation between the ventricles, similar to birds and mammals, but retain the dual aortic arch system found in all non-avian reptiles. This cardiac anatomy allows surgical modification that prevents right-to-left (R–L) cardiac shunt. A R–L shunt is a bypass of the pulmonary circulation and recirculation of oxygen-poor blood back to the systemic circulation and has often been observed during the frequent apnoeic periods of non-avian reptiles, particularly during diving in aquatic species. We eliminated R–L shunt in American alligators (Alligator mississippiensis) by surgically occluding the left aorta (LAo; arising from right ventricle) upstream and downstream of the foramen of Panizza (FoP), and we tested the hypotheses that this removal of R–L shunt would cause afterload-induced cardiac remodelling and adversely affect diving performance. Occlusion of the LAo both upstream and downstream of the FoP for ?21 months caused a doubling of RV pressure and significant ventricular enlargement (average ?65%) compared with age-matched, sham-operated animals. In a separate group of recovered, surgically altered alligators allowed to dive freely in a dive chamber at 23°C, occlusion of the LAo did not alter oxygen consumption or voluntary apnoeic periods relative to sham animals. While surgical removal of R–L shunt causes considerable changes in cardiac morphology similar to aortic banding in mammals, its removal does not affect the respiratory pattern or metabolism of alligators. It appears probable that the low metabolic rate of reptiles, rather than pulmonary circulatory bypass, allows for normal aerobic dives.

Eme, John; Gwalthney, June; Blank, Jason M.; Owerkowicz, Tomasz; Barron, Gildardo; Hicks, James W.

2009-01-01

74

Fibroblast Growth Factor 23, High-Sensitivity Cardiac Troponin, and Left Ventricular Hypertrophy in CKD  

PubMed Central

Background Detectable levels of cardiac troponins are common among individuals with chronic kidney disease (CKD), even in the absence of symptomatic cardiovascular disease. Abnormal cardiac troponin values are associated with coronary artery disease (CAD) and left ventricular hypertrophy (LVH), and predict poor clinical outcomes. Elevated levels of fibroblast growth factor 23 (FGF-23) contribute to LVH in CKD. We investigated the association of FGF-23 and hs-cTnI (high-sensitivity cardiac troponin I) and hs-cTnT (high-sensitivity cardiac troponin T) in CKD, and examined the role of LVH in this association. Study Design Cross-sectional observational study. Setting & Participants 153 stable outpatients with non-dialysis-dependent CKD. Predictor The primary predictor wasFGF-23. Outcomes hs-cTnI, hs-cTnT. Measurements FGF-23, hs-cTnI, hs-cTnT; LVMI assessed by echocardiography; CAC measured by computed tomography. Left ventricular mass index (LVMI) and coronary artery calcification (CAC) were evaluated as potential mediators of the effect of FGF-23 on hs-cTnI/T. Results Mean age was 64 ± 12 (SD) years, mean estimated glomerular filtration rate (eGFR) was 34 ± 11 mL/min/1.73m2, median FGF-23 was 120 (25th–75th percentile, 79–223) RU/mL, median hs-cTnI was 6.5 (25th–75th percentile, 3.5–14.5) pg/mL, and median hs-cTnT was 16.8 (25th–75th percentile, 11.1–33.9) pg/mL. Concentrations of cTnI and cTnT were >99th percentile of a normal population in 42% and 61% of patients, respectively. In unadjusted and multivariable adjusted analyses, hs-cTnI/T were significantly associated with FGF-23. Adjusting for LVMI, but not CAC, weakened the association of FGF-23 and hs-cTnI/T. Limitations Vitamin D levels were not measured. Prevalence of CAD may have been underestimated since it was ascertained by self-report. Conclusions Minimally elevated cTnI and cTnT, detectable by high-sensitivity assays, are associated with elevated FGF-23 levels in stable outpatients with CKD. FGF-23-associated LVH may contribute to detectable hs-cTnI/T levels observed in non-dialysis-dependent CKD patients.

Smith, Kelsey; deFilippi, Christopher; Isakova, Tamara; Gutierrez, Orlando M.; Laliberte, Karen; Seliger, Stephen; Kelley, Walter; Duh, Show-Hong; Hise, Michael; Christenson, Robert; Wolf, Myles; Januzzi, James

2012-01-01

75

Clinical presentation of left atrial cardiac myxoma. A series of 112 consecutive cases.  

PubMed

We analyzed a series of 112 consecutive cases of left atrial myxoma diagnosed in a single French hospital (72 women and 40 men; age range, 5-84 yr) over 40 years, from 1959 to 1998. Symptoms of mitral valve obstruction, the first arm of the classic triad of myxoma presentation, were present in 75 patients (67%), with mostly cardiac failure or malaise. Symptoms of embolism, the second frequent presentation in the classic triad, were observed in 33 cases (29%) with 1 or several locations, essentially cerebral emboli with stroke. Males are statistically at greater risk than females of developing embolic complications. The third arm of the classic triad consists of constitutional symptoms (34%) with fever, weight loss, or symptoms resembling connective tissue disease, due to cytokine (interleukin-6) secretion. Younger and male patients have more neurologic symptoms, and female patients have more systemic symptoms. Seventy-two patients (64%) had cardiac auscultation abnormalities, essentially pseudo-mitral valve disease (53.5%) and more rarely the suggestive tumor plop (15%). The most frequent electrocardiographic sign was left atrial hypertrophy (35%), whereas arrhythmias were uncommon. The greater number of myxoma patients (98) diagnosed preoperatively after 1977 reflects the introduction of echocardiography as a noninvasive diagnostic procedure. However, there was no significant reduction in the average time from onset of symptoms to operation between patients seen in the periods before and after 1977. The tumor diameter ranged from 1 to 15 cm with a weight of between 15 and 180 g (mean, 37 g). The myxoma surface was friable or villous in 35% of the cases, and smooth in the other 65% cases. Myxomas in patients presenting with embolism have a friable surface; those in patients with cardiac symptoms, pseudo-mitral auscultation signs, tumor plop, and electrocardiogram or radiologic signs of left atrium hypertrophy and dilatation are significantly the larger tumors. The long-term prognosis is excellent, and only 4 deaths occurred among our 112 cases over a median follow-up of 3 years. The recurrence rate is low (5%), but long-term follow-up and serial echocardiography are advisable especially for young patients. PMID:11388092

Pinede, L; Duhaut, P; Loire, R

2001-05-01

76

Thrombus formation after left atrial appendage exclusion using an Amplatzer cardiac plug device.  

PubMed

The feasibility and safety of left atrial appendage closure with the Amplatzer cardiac plug (AGA Medical Corp., Minneapolis, MN) have been recently published; no thrombus formation on the device surface has been reported previously. We describe a case of a 66-year-old man with permanent atrial fibrillation, previous stroke, and contraindication for long-term oral anticoagulant therapy. A 22-mm ACP device was deployed successfully without complications. The patient was discharged on acetyl salicylic acid 100 mg and clopidogrel 75 mg daily. After 4 weeks, the patient was admitted for a lower gastrointestinal bleeding and clopidogrel was stopped. A 3-month follow-up echocardiogram confirmed the exclusion of the LAA but it demonstrated the presence of a thrombus on the atrial surface of the device. It was decided to keep the patient on acetyl salicylic acid 100 mg with the addition of enoxaparin 60 mg bid. Transesophageal echocardiogram demonstrated total resolution of the thrombus after 2 months. PMID:21523900

Cruz-Gonzalez, Ignacio; Martín Moreiras, Javier; García, Eulogio

2011-11-15

77

The Influence of Left Lateral Position on Cardiac Output Changes after Head Up Tilt Measured by Impedance Cardiography  

Microsoft Academic Search

Background.The value of the impedance cardiography (IC) method formeasuring cardiac output (CO) with the subject in the left lateral positionhas not yet been established. We compared the CO after a 30° head-up tiltwith the subjects in the supine and left lateral position. Methods.Thirty healthy young volunteers were placed in the supine horizontalposition. CO, stroke volume (SV) and heart rate (HR)

Mirt Kamenik

1999-01-01

78

Association of Left-Heart Dysfunction with Severe Exacerbation of Chronic Obstructive Pulmonary Disease Diagnostic Performance of Cardiac Biomarkers  

Microsoft Academic Search

Rationale: Cardiac biomarkers are used to distinguish acute dyspnea due to left-heart dysfunction from that of pulmonary origin. How- ever, they have not been assessed in the specific setting of acute exacerbation of chronic obstructive pulmonary disease (AECOPD), where they might be released without left-heart impairment. Objective: To assess the accuracy of troponin T and of amino-terminal pro-brain natriuretic peptide

Fekri Abroug; Lamia Ouanes-Besbes; Noureddine Nciri; Noura Sellami; Faouzi Addad; Khaldoun Ben Hamda; Adel Ben Amor; Mohamed F. Najjar; Jalel Knani

79

A Dual-Chamber, Thick-Walled Cardiac Phantom for Use in Cardiac Motion and Deformation Imaging by Ultrasound  

Microsoft Academic Search

Determination of the mechanical properties of the myocardium is crucial for cardiac diagnosis. Cardiac strain and strain rate imaging may enable such quantification. To further develop these methodologies, an experimental setup allowing the recording of ultrasonic deformation data in a reproducible manner is necessary. Such setup with biventricular polyvinyl alcohol heart phantoms has been built. To test this setup, segmental

B. Lesniak-Plewinska; S. Cygan; K. Kaluzynski; J. D'hooge; J. Zmigrodzki; E. Kowalik; M. Kordybach; M. Kowalski

2010-01-01

80

Mechanism of hemodynamic improvement by dual-chamber pacing for severe left ventricular dysfunction: An acute Doppler and catheterization hemodynamic study  

Microsoft Academic Search

Objectives. This study was undertaken to determine the mechanism by which improvement in hemodynamic variables may occur with dual-chamber pacing in patients with severe left ventricular dysfunction.Background. Dual-chamber pacing has recently been proposed as a therapeutic alternative for the relief of symptoms in patients with dilated cardiomyopathy.Methods. Fifteen patients with severe left ventricular systolic dysfunction were studied acutely during atrioventricular

Rick A. Nishimura; David L. Hayes; David R. Holmes; Jamil Tajik

1995-01-01

81

Left Ventricular Flow Analysis: Recent Advances in Numerical Methods and Applications in Cardiac Ultrasound  

PubMed Central

The left ventricle (LV) pumps oxygenated blood from the lungs to the rest of the body through systemic circulation. The efficiency of such a pumping function is dependent on blood flow within the LV chamber. It is therefore crucial to accurately characterize LV hemodynamics. Improved understanding of LV hemodynamics is expected to provide important clinical diagnostic and prognostic information. We review the recent advances in numerical and experimental methods for characterizing LV flows and focus on analysis of intraventricular flow fields by echocardiographic particle image velocimetry (echo-PIV), due to its potential for broad and practical utility. Future research directions to advance patient-specific LV simulations include development of methods capable of resolving heart valves, higher temporal resolution, automated generation of three-dimensional (3D) geometry, and incorporating actual flow measurements into the numerical solution of the 3D cardiovascular fluid dynamics.

Borazjani, Iman; Westerdale, John; McMahon, Eileen M.; Rajaraman, Prathish K.; Heys, Jeffrey J.

2013-01-01

82

The relationship between ventricular electrical delay and left ventricular remodelling with cardiac resynchronization therapy  

PubMed Central

Aims The aim of the present study was to evaluate the relationship between left ventricular (LV) electrical delay, as measured by the QLV interval, and outcomes in a prospectively designed substudy of the SMART-AV Trial. Methods and results This was a multicentre study of patients with advanced heart failure undergoing cardiac resynchronization therapy (CRT) defibrillator implantation. In 426 subjects, QLV was measured as the interval from the onset of the QRS from the surface ECG to the first large peak of the LV electrogram. Left ventricular volumes were measured by echocardiography at baseline and after 6 months of CRT by a blinded core laboratory. Quality of life (QOL) was assessed by a standardized questionnaire. When separated by quartiles based on QLV duration, reverse remodelling response rates (>15% reduction in LV end systolic volume) increased progressively from 38.7 to 68.4% and QOL response rate (>10 points reduction) increased from 50 to 72%. Patients in the highest quartile of QLV had a 3.21-fold increase (1.58–6.50, P = 0.001) in their odds of a reverse remodelling response after correcting for QRS duration, bundle branch block type, and clinical characteristics by multivariate logistic regression analysis. Conclusion Electrical dyssynchrony, as measured by QLV, was strongly and independently associated with reverse remodelling and QOL with CRT. Acute measurements of QLV may be useful to guide LV lead placement.

Gold, Michael R.; Birgersdotter-Green, Ulrika; Singh, Jagmeet P.; Ellenbogen, Kenneth A.; Yu, Yinghong; Meyer, Timothy E.; Seth, Milan; Tchou, Patrick J.

2011-01-01

83

The association of thyroid function with cardiac mass and left ventricular hypertrophy.  

PubMed

Decreased serum TSH levels predict cardiovascular mortality, which could be explained by left ventricular hypertrophy (LVH). The aim of this analysis was to investigate the association between thyroid function and LVH. The population-based Study of Health in Pomerania was conducted in a previously iodine-deficient area. Data of 1510 individuals at least 45 yr of age with echocardiography and without thyroid disorders were analyzed. LVH was defined as a left ventricular mass index (LVMI) exceeding 150 g/m(2) (men) or 120 g/m(2) (women). Overt hyperthyroidism was associated with LVMI (P < 0.01), whereas euthyroid subjects and those with elevated TSH levels did not significantly differ with regard to LVMI. LVH was observed in three (15.0%) subjects with elevated serum TSH levels, in 127 (10.5%) euthyroid persons, in 24 (12.5%) individuals with decreased serum TSH levels, and in four (57.1%) subjects with hyperthyroidism (P < 0.01). Logistic regression analysis identified overt hyperthyroidism as an independent risk factor for LVH (odds ratio, 13.65; 95% confidence interval, 2.83-65.75; P < 0.01). There is an association between thyroid function status, cardiac mass, and LVH. Hyperthyroidism is an independent risk factor for LVH. PMID:15522926

Dörr, Marcus; Wolff, Birger; Robinson, Daniel M; John, Ulrich; Lüdemann, Jan; Meng, Wieland; Felix, Stephan B; Völzke, Henry

2005-02-01

84

Cardiac contractility modulation with nonexcitatory electric signals improves left ventricular function in dogs with chronic heart failure  

Microsoft Academic Search

Background: Nonexcitatory electrical, signals termed cardiac contractility modulation (CCM) have been shown to improve contractile force of isolated papillary muscles. In this study, we examined the effects of CCM signal delivery on left ventricular function in dogs with chronic heart failure (HF). Methods and Results: Chronic HF (ejection fraction ?35%) was produced in 7 dogs by intracoronary microembolizations. The CCM

Hideaki Morita; George Suzuki; Walid Haddad; Yuval Mika; Elaine J. Tanhehco; Victor G. Sharov; Sidney Goldstein; Shlomo Ben-Haim; Hani N. Sabbah

2003-01-01

85

Left ventricular thrombus mimicking primary cardiac tumor in a patient with primary antiphospholipid syndrome and recurrent systemic embolism.  

PubMed

Primary antiphospholipid syndrome (APS) is a well-defined entity characterized by spontaneous and recurrent abortion, thrombocytopenia and recurrent vascular thromboses (arterial and venous). Left ventricular thrombus mimicking primary cardiac tumor with recurrent systemic embolism has not been previously reported. In this report we describe a 39 year-old man admitted to hospital presenting with left hemiparesis and a peripheral embolism. He had no history of thrombotic events. Transthoracic echocardiography showed a large, polypoid and mobile mass (4.0 x 1.2 cm) attached to the apex of the left ventricle, highly suggestive of primary cardiac tumor. The patient subsequently underwent open heart surgery. The histological examination showed an older thrombus and a fresh thrombus. Post-operative laboratory tests showed lupus anticoagulant activity, confirming the primary APS diagnosis. The patient initiated treatment with oral anticoagulation (INR levels between 2 and 3) and was discharged 29 days after surgery. At ten month follow-up, he was symptom-free with long-term anticoagulation therapy. No evidence of intracardiac mass recurrence on two-dimensional echocardiography was seen. Intracardiac thrombus has been rarely reported as a complication of primary APS. Left ventricular mass mimicking primary cardiac tumor with recurrent systemic embolism has not been previously reported. Pre-operative investigations could not distinguish such a thrombus from a cardiac tumor and the diagnosis was made post-operatively. PMID:19950093

Cianciulli, Tomás F; Saccheri, María C; Lax, Jorge A; Neme, Roberto O; Sevillano, Juan F Alvarez; Maiori, María E; Lound, Sebastian Fandino; Parisi, Coloma E; Prezioso, Horacio A; Vidal, Luis A

2009-01-01

86

Cardiac Magnetic Resonance Imaging in the Diagnosis of Anterolateral Left Ventricular Ballooning, a Variant of Classic Takotsubo Cardiomyopathy  

PubMed Central

Transient left ventricular apical ballooning syndrome is characterized by transient akinesis of the left ventricular apex with basal wall hyperkinesis; this is also known as Takotsubo cardiomyopathy. There are three distinct contractile LV patterns described in the literature: apical, midventricular, and basal ballooning. The apical ballooning pattern is the most frequent pattern. We describe the case of a transient anterolateral left ventricular ballooning fulfilling the definition of Takotsubo cardiomyopathy except for the contractile LV pattern. The diagnosis was supported by cardiac magnetic resonance imaging and by the fact that the anterolateral ballooning resolved completely after 6 weeks.

Zbinden, R.; Mutter, M.; Weishaupt, D.

2012-01-01

87

Sudden cardiac arrest due to subtotal absence of left-sided pericardium--case report and review of the literature.  

PubMed

Congenital absence of the pericardium is a very rare cardiac malformation, usually diagnosed fortuitously on autopsy or surgery. Symptoms related to these abnormalities are usually benign, and fatalities reported in the literature are almost exclusively secondary to herniation of the heart through a partial defect. We present the unusual case of a 44-year-old woman admitted for sudden cardiac arrest. Initial evaluation suggested acute anterior myocardial infarction, but further investigation ruled out coronary heart disease. No arrhythmia could be initiated on electrophysiological study, and absence of most of the left pericardium was confirmed by cardiac magnetic resonance imaging. After the exclusion of common etiologies such as idiopathic ventricular fibrillation, transient great vessel torsion due to hypermobility of the heart with secondary malignant arrhythmia was considered to be the most likely mechanism for the sudden cardiac arrest. A review of the available literature on clinical presentation, diagnostic tools, and therapeutic options is also presented. PMID:22698265

Steinberg, Christian; Pelletier, Marie-Josée; Perron, Jean; Kumar, Andreas; Champagne, Jean

2013-01-01

88

Recommendations for chamber quantification  

Microsoft Academic Search

Abstract Quantification of cardiac chamber size, ventricular mass and function ranks among,the most,clinically important,and most,frequently,requested,tasks of echocardiography. Over the last decades, echocardiographic methods and techniques haveimprovedandexpandeddramatically,duetotheintroductionofhigherfrequency transducers, harmonic imaging, fully digital machines, left-sided contrast agents, and other technological advancements. Furthermore, echocardiography due to its porta- bility and versatility is now used in emergency rooms, operating rooms, and intensive care units.

Roberto M. Lang; Michelle Bierig; Richard B. Devereux; Frank A. Flachskampf; Elyse Foster; Patricia A. Pellikka; Michael H. Picard; Mary J. Roman; James Seward; Jack Shanewise; Scott Solomon; Kirk T. Spencer; John Sutton; William Stewart

2006-01-01

89

Left Ventricular Hypertrophy in New Hemodialysis Patients without Symptomatic Cardiac Disease  

PubMed Central

Background and objectives: Although left ventricular hypertrophy (LVH) is a characteristic finding in hemodialysis (HD) populations, few risk factors for progressive LVH have been identified. Design, setting, participants, & measurements: As part of a multinational, blinded, randomized, controlled trial that demonstrated no effect of hemoglobin targets on LV size, 596 incident HD patients, without symptomatic cardiac disease or cardiac dilation, had baseline echocardiograms within 18 months of starting dialysis and subsequently at 24, 48, and 96 weeks later. A wide array of baseline risk factors were assessed, as were BP and hemoglobin levels during the trial. Results: The median age and duration of dialysis were 51.5 years and 9 months, respectively. LV mass index (LVMI) rose substantially during follow-up (114.2 g/m2 at baseline, 121 at week 48, 123.4 at week 48, and 128.3 at week 96), as did fractional shortening, whereas LV volume (68.7, 70.1, 68.7, and 68.1 ml/m2) and E/A ratio remained unchanged. At baseline, the only multivariate associations of LVMI were gender and N terminal pro–B type natriuretic peptide. Comparing first and last echocardiograms in those without LVH at baseline, independent predictors of increase in LVMI were higher time-integrated systolic BP and cause of ESRD. An unadjusted association between baseline LVMI and subsequent cardiovascular events or death was eliminated by adjusting for age, diabetes, systolic BP, and N terminal pro–B type natriuretic peptide. Conclusions: Progressive concentric LVH and hyperkinesis occur in HD patients, which is partly explained by hypertension but not by a wide array of potential risk factors, including anemia.

Foley, Robert N.; Curtis, Bryan M.; Randell, Edward W.

2010-01-01

90

Postinfarct cytokine therapy regenerates cardiac tissue and improves left ventricular function.  

PubMed

We systematically investigated the comparative efficacy of three different cytokine regimens, administered after a reperfused myocardial infarction, in regenerating cardiac tissue and improving left ventricular (LV) function. Wild-type (WT) mice underwent a 30-minute coronary occlusion followed by reperfusion and received vehicle, granulocyte colony-stimulating factor (G-CSF)+Flt-3 ligand (FL), G-CSF+stem cell factor (SCF), or G-CSF alone starting 4 hours after reperfusion. In separate experiments, chimeric mice generated by reconstitution of radioablated WT mice with bone marrow from enhanced green fluorescent protein (EGFP) transgenic mice underwent identical protocols. Mice were euthanized 5 weeks later. Echocardiographically, LV function was improved in G-CSF+FL- and G-CSF+SCF-treated but not in G-CSF-treated mice, whereas LV end-diastolic dimensions were smaller in all three groups. Morphometrically, cytokine-treated hearts had smaller LV diameter and volume. Numerous EGFP-positive cardiomyocytes, capillaries, and arterioles were noted in the infarcted region in cytokine-treated chimeric mice treated with G-CSF+FL or G-CSF+SCF, but the numbers were much smaller in G-CSF-treated mice. G-CSF+FL therapy mobilized bone marrow-derived cells exhibiting increased expression of surface antigens (CD62L and CD11a) that facilitate homing. We conclude that postinfarct cytokine therapy with G-CSF+FL or G-CSF+SCF limits adverse LV remodeling and improves LV performance by promoting cardiac regeneration and probably also by exerting other beneficial actions unrelated to regeneration, and that G-CSF alone is less effective. PMID:16556872

Dawn, Buddhadeb; Guo, Yiru; Rezazadeh, Arash; Huang, Yiming; Stein, Adam B; Hunt, Greg; Tiwari, Sumit; Varma, Jai; Gu, Yan; Prabhu, Sumanth D; Kajstura, Jan; Anversa, Piero; Ildstad, Suzanne T; Bolli, Roberto

2006-04-28

91

Postinfarct Cytokine Therapy Regenerates Cardiac Tissue and Improves Left Ventricular Function  

PubMed Central

We systematically investigated the comparative efficacy of three different cytokine regimens, administered after a reperfused myocardial infarction, in regenerating cardiac tissue and improving left ventricular (LV) function. Wild-type (WT) mice underwent a 30-minute coronary occlusion followed by reperfusion and received vehicle, granulocyte colony-stimulating factor (G-CSF)+Flt-3 ligand (FL), G-CSF+stem cell factor (SCF), or G-CSF alone starting 4 hours after reperfusion. In separate experiments, chimeric mice generated by reconstitution of radioablated WT mice with bone marrow from enhanced green fluorescent protein (EGFP) transgenic mice underwent identical protocols. Mice were euthanized 5 weeks later. Echocardiographically, LV function was improved in G-CSF+FL– and G-CSF+SCF–treated but not in G-CSF–treated mice, whereas LV end-diastolic dimensions were smaller in all three groups. Morphometrically, cytokine-treated hearts had smaller LV diameter and volume. Numerous EGFP-positive cardiomyocytes, capillaries, and arterioles were noted in the infarcted region in cytokine-treated chimeric mice treated with G-CSF+FL or G-CSF+SCF, but the numbers were much smaller in G-CSF–treated mice. G-CSF+FL therapy mobilized bone marrow–derived cells exhibiting increased expression of surface antigens (CD62L and CD11a) that facilitate homing. We conclude that postinfarct cytokine therapy with G-CSF+FL or G-CSF+SCF limits adverse LV remodeling and improves LV performance by promoting cardiac regeneration and probably also by exerting other beneficial actions unrelated to regeneration, and that G-CSF alone is less effective.

Dawn, Buddhadeb; Guo, Yiru; Rezazadeh, Arash; Huang, Yiming; Stein, Adam B.; Hunt, Greg; Tiwari, Sumit; Varma, Jai; Gu, Yan; Prabhu, Sumanth D.; Kajstura, Jan; Anversa, Piero; Ildstad, Suzanne T.; Bolli, Roberto

2013-01-01

92

Optimized temporary bi-ventricular pacing improves haemodynamic function after on-pump cardiac surgery in patients with severe left ventricular systolic dysfunction: a two-centre randomized control trial  

PubMed Central

OBJECTIVES Optimized temporary bi-ventricular (BiV) pacing may benefit heart failure patients after on-pump cardiac surgery compared with conventional dual-chamber right ventricular (RV) pacing. An improvement in haemodynamic function with BiV pacing may reduce the duration of ‘Level 3’ intensive care. METHODS Thirty-eight patients in sinus rhythm, ejection fraction ?35%, undergoing on-pump surgical revascularization, valve surgery or both were enrolled in this study. Before closing the sternum, temporary epicardial pacing wires were attached to the right atrium, RV outflow tract and basal posterolateral wall of the left ventricle. Patients were randomly assigned to postoperative BiV pacing with the optimization of the atrio- (AV) and inter-ventricular (VV) pacing intervals (Group 1) or conventional dual-chamber right AV pacing (Group 2). The primary end-point was the duration of ‘Level 3’ intensive care. Secondary end-points included cardiac output which was measured by thermodiluation at admission to the intensive care unit and at 6 and 18 h later, in five different pacing modes. RESULTS The duration of ‘Level 3’ care was similar between groups (40 ± 35 vs 54 ± 63 h; Group 1 vs 2; P = 0.43). Cardiac output was similar in all pacing modes at baseline. At 18 h, cardiac output with BiV pacing (5.8 l/min) was 7% higher than atrial inhibited (5.4 l/min) and 9% higher than dual-chamber RV pacing (5.3 l/min; P = 0.02 and 0.001, respectively). Optimization of the VV interval produced a further 4% increase in cardiac output compared with baseline settings (P = 0.005). CONCLUSIONS Postoperative haemodynamic function may be enhanced by temporary BiV pacing of high-risk patients after on-pump cardiac surgery.

Russell, Stuart J.; Tan, Christine; O'Keefe, Peter; Ashraf, Saeed; Zaidi, Afzal; Fraser, Alan G.; Yousef, Zaheer R.

2012-01-01

93

The Mechanics of Left Ventricular Contraction in Acute Experimental Cardiac Failure*  

PubMed Central

The effects of acute cardiac failure induced by pentobarbital or pronethalol on the basic mechanical properties of the intact left ventricle were examined in the dog, and the influence on auxotonic and isovolumic contractions of the increase in end-diastolic volume that usually accompanies cardiac failure was assessed. The right heart bypass preparation was employed, and isovolumic beats were induced by sudden balloon occlusion of the aortic root. The ventricular pressure-volume curve was determined directly, and the mechanical responses of the myocardial fibers and contractile elements were calculated. When end-diastolic pressure was held constant, failure reduced the extent of circumferential fiber shortening, and the tension-velocity relation calculated during isovolumic beats was always shifted, with reductions in both maximal velocity (average decrease 30%) and maximal developed tension (average 23%); in addition, during failure achievement of maximal contractile element velocity and maximal tension was delayed, whereas the total duration of contraction was always prolonged. Acetylstrophanthidin tended to reverse all of these changes. When end-diastolic volume was augmented during failure at a constant stroke volume, the extent of circumferential fiber shortening was reduced (3.82 cm to 2.02 cm), and during ejection the fiber and contractile element velocities were diminished at wall tensions comparable to control; maximal velocity and velocity at peak tension were also decreased. The tension-velocity relation during isovolumic beats was shifted by failure with consistent reductions in maximal shortening velocity, but changes in maximal tension were small. Maximal instantaneous power was always reduced by failure, and a striking alteration occurred in the relation between work expended in stretching the series elastic component and the external work; the former, “internal work,” increased by an average of 90%, the latter diminished by 11%, and the total contractile element work remained essentially unchanged. These findings are discussed within the framework of a three dimensional model that included fiber length, wall tension, and contractile element velocity. The experimental techniques employed appear to permit a more complete definition of the abnormalities of the ventricular myocardium in experimental failure. They are potentially applicable in the closed-chest animal and allow quantitative determinations of the contractile properties of the left ventricle. Images

Ross, John; Covell, James W.; Sonnenblick, Edmund H.

1967-01-01

94

Estimation of left ventricular ejection fraction by computerized single cardiac probe system with echocardiogram  

SciTech Connect

The authors developed a computerized single cardiac probe system combined with echocardiogram which permits the physician to position the detector more easily and properly. With this system left ventricular ejection fraction (LVEF) can be estimated by the three different modes: first pass (FP) mode, beat-by-beat (B-B) mode and ECG multigated (MG) mode. In FP mode complex demodulation technique is applied for estimation of the background counts. The purpose of this paper is to describe the accuracy and reproducibility of the LVEF estimated by this system. In 40 patients with various heart diseases, the LVEFs estimated by this system using above-mentioned 3 modes were compared with those of obtained by gamma camera. There were good correlations between the LVEFs estimated by each of the 3 modes of this system and obtained by gamma camera. The correlation coefficient (r) between the LVEFs estimated FP mode, B-B mode and MG mode, and those of by gamma camera was 0.938, 0.932, and 0.930, respectively. In 15 patients FP mode study was repeated continuously and LVEFs obtained in the initial and repeat studies were compared. There was good agreement between these results (r=0.953). In 12 patients positioning of the probe over the left ventricle and background area was repeated 5 times and LVEFs were estimated each time by B-B mode. There was no significant standard deviation compared to the mean LVEFs in each patient; the percent coefficient of variation was less than 8.0%. The authors conclude that their results suggest that LVEF can be estimated accurately be each of the 3 modes of this system and reproducibility seems to be sufficient for clinical studies.

Suzuki, Y.; Ide, M.; Kenemoto, N.; Tomoda, H.; Nakamura, M.

1984-01-01

95

Biological, electrical and echocardiographic indices versus cardiac magnetic resonance imaging in diagnosing left ventricular hypertrophy.  

PubMed

The aim of this study was to compare the diagnostic performance of N-terminal pro-brain natriuretic peptide (NT-proBNP), electrocardiographic (ECG) criteria and transthoracic echocardiography (TTE) versus cardiac magnetic resonance imaging in detecting left ventricular hypertrophy (LVH). The study included 42 hypertensive subjects with mean±s.d. age 48.1±12.3 years, 57.1% men, 24-h ambulatory blood pressure 144/89?mm?Hg, left ventricular ejection fraction >50%, without symptoms of heart failure, and not taking any drugs that interfere with hormonal regulation. The accuracies of the methods in detecting LVH were compared at two diagnostic LVH cutoffs: low, 83?g?m(-2) in men and 67?g?m(-2) in women; and high, 96?g?m(-2) in men and 81?g?m(-2) in women. With the low and high LVH cutoffs, the areas under the receiver-operating characteristic curves and the optimal values for NT-proBNP were 0.761, 0.849, 200 and 421?pg?ml(-1), respectively. An NT-proBNP level under 30?pg?ml(-1) ruled out LVH with 100% sensitivity. The optimal values and literature-based values of NT-proBNP allowed a correct classification of 73-81% of the subjects. In 80-90% of the cases, the diagnostic accuracy of NT-proBNP was close to that of ECG criteria but lower than that of TTE criteria. Interestingly, combining ECG criteria and NT-proBNP level improved the diagnostic performance to be at least comparable to that of TTE: the percentages of correctly classified subjects were 73-95% vs. 67-86%, respectively. Of note, the range considers both diagnostic LVH cutoffs. The simultaneous use of ECG criteria and NT-proBNP plasma levels seemed to be powerful enough to detect LVH in most hypertensive subjects. PMID:24132010

Courand, Pierre-Yves; Gaudebout, Nathalie; Mouly-Bertin, Carine; Thomson, Vivien; Fauvel, Jean-Pierre; Bricca, Giampiero; Lantelme, Pierre

2014-05-01

96

Coronary sinus ostial atresia and persistent left-sided superior vena cava: clinical significance and strategies for cardiac resynchronization therapy.  

PubMed

A 48-year-old male patient underwent cardiac resynchronization therapy defibrillator implantation, and he was found to have atresia of the coronary sinus ostium with venous drainage occurring via a persistent left-sided superior vena cava, which was connected to the right-sided superior vena cava by the innominate vein. This is a rare benign cardiac anomaly that can pose problems when the coronary sinus needs to be cannulated. To identify the course of the coronary sinus, a coronary angiogram can be performed with attention directed to the venous phase of the angiogram. Although the technical difficulty of coronary sinus cannulation increases, various catheters, wires, and delivery systems can be utilized and this anomaly does not usually prevent successful left ventricular lead placement in cardiac resynchronization therapy via a left-sided superior vena cava approach. There however needs to be consideration regarding caliber of the left-sided superior vena cava being sufficiently large to avoid compromise of venous drainage after lead insertion. PMID:24436612

Lim, Paul Chun Yih; Baskaran, Lohendran; Ho, Kah Leng; Teo, Wee Siong; Ching, Chi Keong

2013-09-01

97

Perforation of the right ventricle during cardiac resynchronisation therapy upgrade not related to a coexisting persistent left superior vena cava.  

PubMed

Right ventricle (RV) perforation is a complication that may arise during device implants. We present the case of a patient undergoing cardiac resynchronisation therapy upgrade that was complicated with an RV perforation. The lead was successfully repositioned with a good final outcome. Despite being uncommon, persistence of the left superior vena cava is the most frequent venous cardiac anomaly and may pose challenges during the implant procedure, namely when the right superior vena cava (RSVC) is absent. Still, in this patient it was not related to the event, as the leads were advanced through the RSVC. PMID:22922915

Providência, Rui; Paiva, Luís V; Cação, Romeu; Mota, Paula

2012-01-01

98

Tempol prevents cardiac oxidative damage and left ventricular dysfunction in the PPAR-? KO mouse.  

PubMed

Peroxisome proliferator-activated receptor (PPAR)-? deletion induces a profound decrease in MnSOD activity, leading to oxidative stress and left ventricular (LV) dysfunction. We tested the hypothesis that treatment of PPAR-? knockout (KO) mice with the SOD mimetic tempol prevents the heart from pathological remodelling and preserves LV function. Twenty PPAR-? KO mice and 20 age-matched wild-type mice were randomly treated for 8 wk with vehicle or tempol in the drinking water. LV contractile parameters were determined both in vivo using echocardiography and ex vivo using papillary muscle mechanics. Translational and posttranslational modifications of myosin heavy chain protein as well as the expression and activity of major antioxidant enzymes were measured. Tempol treatment did not affect LV function in wild-type mice; however, in PPAR-? KO mice, tempol prevented the decrease in LV ejection fraction and restored the contractile parameters of papillary muscle, including maximum shortening velocity, maximum extent of shortening, and total tension. Moreover, compared with untreated PPAR-? KO mice, myosin heavy chain tyrosine nitration and anion superoxide production were markedly reduced in PPAR-? KO mice after treatment. Tempol also significantly increased glutathione peroxidase and glutathione reductase activities (~ 50%) in PPAR-? KO mice. In conclusion, these findings demonstrate that treatment with the SOD mimetic tempol can prevent cardiac dysfunction in PPAR-? KO mice by reducing the oxidation of contractile proteins. In addition, we show that the beneficial effects of tempol in PPAR-? KO mice involve activation of the glutathione peroxidase/glutathione reductase system. PMID:23542920

Guellich, Aziz; Damy, Thibaud; Conti, Marc; Claes, Victor; Samuel, Jane-Lise; Pineau, Thierry; Lecarpentier, Yves; Coirault, Catherine

2013-06-01

99

4-D Cardiac MR Image Analysis: Left and Right Ventricular Morphology and Function  

PubMed Central

In this study, a combination of active shape model (ASM) and active appearance model (AAM) was used to segment the left and right ventricles of normal and Tetralogy of Fallot (TOF) hearts on 4-D (3-D+time) MR images. For each ventricle, a 4-D model was first used to achieve robust preliminary segmentation on all cardiac phases simultaneously and a 3-D model was then applied to each phase to improve local accuracy while maintaining the overall robustness of the 4-D segmentation. On 25 normal and 25 TOF hearts, in comparison to the expert traced independent standard, our comprehensive performance assessment showed subvoxel segmentation accuracy, high overlap ratios, good ventricular volume correlations, and small percent volume differences. Following 4-D segmentation, novel quantitative shape and motion features were extracted using shape information, volume-time and dV/dt curves, analyzed and used for disease status classification. Automated discrimination between normal/TOF subjects achieved 90%–100% sensitivity and specificity. The features obtained from TOF hearts show higher variability compared to normal subjects, suggesting their potential use as disease progression indicators. The abnormal shape and motion variations of the TOF hearts were accurately captured by both the segmentation and feature characterization.

Wahle, Andreas; Johnson, Ryan K.; Scholz, Thomas D.; Sonka, Milan

2010-01-01

100

Bidirectional ventricular tachycardia with alternating right and left bundle branch block morphology in a patient with metastatic cardiac tumors.  

PubMed

A case is reported of bidirectional ventricular tachycardia and syncope in a 16-year-old male with a previous history of a paratesticular rhabdomyosarcoma that achieved complete remission with treatment. At the electrophysiological study, frequent ectopy of both right and left bundle branch block pattern were present, with runs of monomorphic and bidirectional VT alternating the two morphologies. The study suggested a single focus at the interventricular septum with two exit sites, depolarizing the right and left ventricle in an alternate fashion. Reassessment of the malignancy status showed multiple cardiac metastases with a 4 mm nodule at the interventricular septum. PMID:16836679

Dorfman, Fábio Kirzner; Mesas, Cézar Eumann; Cirenza, Cláudio; de Paola, Angelo Amato Vincenzo

2006-07-01

101

Simplified technique for implantation of a left ventricular assist system after previous cardiac operations  

Microsoft Academic Search

Implantation of a left ventricular assist system through a left thoracotomy in patients with multiple previous heart operations avoids reopening the sternum and the possible consequent serious complications.

Miralem Pasic; Peter Bergs; Ewald Hennig; Matthias Loebe; Yuguo Weng; Roland Hetzer

1999-01-01

102

A DATA-DRIVEN APPROACH TO PRIOR EXTRACTION FOR SEGMENTATION OF LEFT VENTRICLE IN CARDIAC MR IMAGES  

PubMed Central

In this paper, we propose a data-driven approach that extracts prior information for segmentation of the left ventricle in cardiac MR images of transplanted rat hearts. In our approach, probabilistic priors are generated from prominent features, i.e., corner points and scale-invariant edges, for both endo-and epi-cardium segmentation. We adopt a level set formulation that integrates probabilistic priors with intensity, texture, and edge information for segmentation. Our experimental results show that with minimal user input, representative priors are correctly extracted from the data itself, and the proposed method is effective and robust for segmentation of the left ventricle myocardium even in images with very low contrast. More importantly, it avoids inter- and intra- observer variations and makes accurate quantitative analysis of low-quality cardiac MR images possible.

Jia, Xiao; Li, Chao; Sun, Ying; Kassim, Ashraf A.; Wu, Yijen L.; Hitchens, T. Kevin; Ho, Chien

2010-01-01

103

Rupture of a giant cardiac hydatid cyst in the left ventricular free wall: successful surgical management of a rare entity  

PubMed Central

Hydatid cyst of heart is a rare but potentially fatal site of pathology, especially left ventricular free wall. We managed a successful surgical treatment on a case of a 24 year old man who had a giant cardiac hydatid cyst (71 x 64 mm) that ruptured left ventricular free wall. The cyst was excised gently and all the cystic materials were removed, the cyst cavity was closed with GORE-TEX soft tissue patch. The patient was discharged on the 9th postoperative day without symptoms. This case is different from other cardiac hydatid cysts that have been reported in literature previously; because this patient was young and had advanced phase of the disease that presented to our clinic lately. Additionally, the cyst had limited both ventricular volumes significantly.

Hosseinian, Adallat; Mohammadzadeh, Alireza; Shahmohammadi, Ghader; Hasanpour, Mohammad; Maleki, Nasrollah; Doustkami, Hossein; Haghdoost, Zarafshan

2013-01-01

104

Serum Uric Acid Is Associated with Left Ventricular Hypertrophy Independent of Serum Parathyroid Hormone in Male Cardiac Patients  

PubMed Central

Background Several studies have shown that serum uric acid (UA) is associated with left ventricular (LV) hypertrophy. Serum levels of parathyroid hormone (PTH), which has bbe shown to be correlated with UA, is also known to be associated with cardiac hypertrophy; however, whether the association between UA and cardiac hypertrophy is independent of PTH remains unknown. Purpose We investigated whether the relationship between serum uric acid (UA) and LV hypertrophy is independent of intact PTH and other calcium-phosphate metabolism-related factors in cardiac patients. Methods and Results In a retrospective study, the association between UA and left ventricular mass index was assessed among 116 male cardiac patients (mean age 65±12 years) who were not taking UA lowering drugs. The median UA value was 5.9 mg/dL. Neither age nor body mass index differed significantly among the UA quartile groups. Patients with higher UA levels were more likely to be taking loop diuretics. UA showed a significant correlation with intact PTH (R?=?0.34, P<0.001) but not with other calcium-phosphate metabolism-related factors. Linear regression analysis showed that log-transformed UA showed a significant association with left ventricular mass index, and this relationship was found to be significant exclusively in patients who were not taking loop and/or thiazide diuretics. Multivariate logistic regression analysis showed that log-transformed UA was independently associated with LV hypertrophy with an odds ratio of 2.79 (95% confidence interval 1.48–5.28, P?=?0.002 per one standard deviation increase). Conclusions Among cardiac patients, serum UA was associated with LV hypertrophy, and this relationship was, at least in part, independent of intact PTH levels, which showed a significant correlation with UA in the same population.

Fujita, Shu-ichi; Okamoto, Yusuke; Shibata, Kensaku; Morita, Hideaki; Ito, Takahide; Sohmiya, Koichi; Hoshiga, Masaaki; Ishizaka, Nobukazu

2013-01-01

105

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

PubMed Central

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

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

2013-01-01

106

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

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

107

Targeted Inactivation of Cerberus Like-2 Leads to Left Ventricular Cardiac Hyperplasia and Systolic Dysfunction in the Mouse  

PubMed Central

Previous analysis of the Cerberus like 2 knockout (Cerl2?/?) mouse revealed a significant mortality during the first day after birth, mostly due to cardiac defects apparently associated with randomization of the left-right axis. We have however, identified Cerl2-associated cardiac defects, particularly a large increase in the left ventricular myocardial wall in neonates that cannot be explained by laterality abnormalities. Therefore, in order to access the endogenous role of Cerl2 in cardiogenesis, we analyzed the embryonic and neonatal hearts of Cerl2 null mutants that did not display a laterality phenotype. Neonatal mutants obtained from the compound mouse line Cer2?/?::Mlc1v-nLacZ24+, in which the pulmonary ventricle is genetically marked, revealed a massive enlargement of the ventricular myocardium in animals without laterality defects. Echocardiography analysis in Cerl2?/? neonates showed a left ventricular systolic dysfunction that is incompatible with a long lifespan. We uncovered that the increased ventricular muscle observed in Cerl2?/? mice is caused by a high cardiomyocyte mitotic index in the compact myocardium which is mainly associated with increased Ccnd1 expression levels in the left ventricle at embryonic day (E) 13. Interestingly, at this stage we found augmented left ventricular expression of Cerl2 levels when compared with the right ventricle, which may elucidate the regionalized contribution of Cerl2 to the left ventricular muscle formation. Importantly, we observed an increase of phosphorylated Smad2 (pSmad2) levels in embryonic (E13) and neonatal hearts indicating a prolonged TGF?s/Nodal-signaling activation. Concomitantly, we detected an increase of Baf60c levels, but only in Cerl2?/? embryonic hearts. These results indicate that independently of its well-known role in left-right axis establishment Cerl2 plays an important role during heart development in the mouse, mediating Baf60c levels by exerting an important control of the TGF?s/Nodal-signaling pathway.

Araujo, Ana Carolina; Marques, Sara; Belo, Jose Antonio

2014-01-01

108

Deconvolution analysis in radionuclide quantitation of left-to-right cardiac shunts.  

PubMed

A poor bolus injection results in an unsatisfactory quantitative radionuclide angiocardiogram in as many as 20% of children with possible, left-to-right (L-R) cardiac shunts. Deconvolution analysis was applied to similar studies in experimental animals to determine whether dependence on the input bolus could be minimized. Repeated good-bolus, prolonged (greater than 2.5 sec), or multiple-peak injections were made in four normal dogs and seven dogs with surgically created atrial septal defects (ASD). QP/QS was determined using the gamma function. The mean QP/QS from ten good-bolus studies in each animal was used as the standard for comparison. In five trials in normal animals, where a prolonged or double-peak bolus led to a shunt calculation (QP/QS greater than 1.2 : 1), deconvolution resulted in QP/QS = 1.0. Deconvolution improved shunt quantitation in eight of ten trials in animals that received a prolonged bolus. The correlation between the reference QP/QS and the QP/QS calculated from uncorrected bad bolus studies was only 0.39 (p greater than 0.20). After deconvolution using a low pass filter, the correlation improved significantly (r = 0.77, p less than 0.01). The technique gave inconsistent results with multiple-peak bolus injections. Deconvolution analysis in these studies is useful in preventing normals from being classified as shunts, and in improving shunt quantitation after a prolonged bolus. Clinical testing of this technique in children with suspected L-R shunts seems warranted. PMID:536823

Alderson, P O; Douglass, K H; Mendenhall, K G; Guadiani, V A; Watson, D C; Links, J M; Wagner, H N

1979-06-01

109

Selective non-operative management of a left ventricular pseudoaneurysm after penetrating cardiac wound  

PubMed Central

Post-traumatic cardiac pseudoaneurysm (PSA) is a rare, potentially life-threatening complication after penetrating cardiac injury. Early surgical intervention has been the treatment of choice for this sequela due to the risk of rupture. Nevertheless, selective non-operative management (SNOM) has been practiced in patients with postinfarct PSA that are small and stable. We report a case of a post-traumatic cardiac PSA subjected to SNOM.

Talving, Peep; Branco, Bernardino C.; Plurad, David; Inaba, Kenji; Shriki, Jabi E.; Nguyen, Nhien; Lustenberger, Thomas; Demetriades, Demetrios

2012-01-01

110

Selective non-operative management of a left ventricular pseudoaneurysm after penetrating cardiac wound.  

PubMed

Post-traumatic cardiac pseudoaneurysm (PSA) is a rare, potentially life-threatening complication after penetrating cardiac injury. Early surgical intervention has been the treatment of choice for this sequela due to the risk of rupture. Nevertheless, selective non-operative management (SNOM) has been practiced in patients with postinfarct PSA that are small and stable. We report a case of a post-traumatic cardiac PSA subjected to SNOM. PMID:23248509

Talving, Peep; Branco, Bernardino C; Plurad, David; Inaba, Kenji; Shriki, Jabi E; Nguyen, Nhien; Lustenberger, Thomas; Demetriades, Demetrios

2012-10-01

111

Repolarization dispersion and sudden cardiac death in patients with impaired left ventricular function  

Microsoft Academic Search

Aims Prolongation of repolarization dispersion measured from the 12-lead surface ECG has been associated with sudden cardiac death and ventricular tachyarrhythmia in a variety of heart disorders. This study tested the hypothesis that increased repolarization dispersion is of prognostic value in identifying chronic heart failure patients at high risk of sudden cardiac death and ventricular tachyarrhythmia. Results In 163 patients,

G.-S. Fu; A. Meissner; R. Simon

112

Assessment of left ventricular dyssynchrony and cardiac function in patients with different pacing modes using real-time three-dimensional echocardiography: Comparison with tissue Doppler imaging  

PubMed Central

The aim of this study was to evaluate the left ventricular mechanical dyssynchrony (LVMD) and left ventricular dysfunction of patients in AAI, DDD and VVI pacing modes using real-time three-dimensional echocardiography (RT3DE) and tissue Doppler imaging (TDI). The results from the RT3DE and TDI were subsequently compared. Twenty patients with sick sinus syndrome (SSS) who had undergone the implantation of a dual-chamber pacemaker were enrolled in this study and the pacemakers were programmed to AAI, DDD and VVI modes, sequentially. The RT3DE and TDI parameters were obtained following pacing for 24 h in each mode. With RT3DE, we measured the systolic dyssynchrony indices, including Tmsv16-SD%, Tmsv12-SD%, Tmsv6-SD%, Tmsv16-Dif%, Tmsv12-Dif% and Tmsv6-Dif%, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF), respectively. With TDI, we measured the standard deviation and the maximal difference in time from the QRS onset to the peak systolic velocity for 12 left ventricular myocardial segments, i.e. Ts-SD and Ts-Dif, respectively. The results showed that the Tmsv16-SD% and Ts-SD in the AAI mode were significantly lower than those in the DDD and VVI modes (P<0.05); however, there were no significant differences between the DDD and VVI modes (P>0.05). The LVEF in the AAI, DDD and VVI modes was 63.1±8.9, 58.6±11.2 and 57.9±7.6%, respectively (P>0.05). There were negative correlations between the LVEF and Tmsv16-SD% (r, ?0.651; P<0.001) and Ts-SD (r, ?0.649; P<0.0001). A moderate correlation (r, 0.698; P<0.0001) was observed between Tmsv16-SD% and Ts-SD. The concordance rate between Tmsv16-SD% and Ts-SD for detecting LVMD was 76%. This study showed that DDD and VVI pacing modes induced significant LVMD and a reduction in LVEF, unlike the AAI pacing mode. RT3DE and TDI were capable of objectively evaluating LVMD; however, each method had certain faults. At present, there is a lack of a uniform standard for assessing LVMD; therefore, the use of a variety of techniques and indices is necessary in order to comprehensively evaluate LVMD in patients with different cardiac pacing modes.

DAI, MIN; LU, JUAN; QIAN, DA-JUN; CAI, JIAN-FENG; LIU, XIAO-YU; WU, XIAO-QING; YANG, ZHEN-YU; LI, XIAO-RONG; WANG, RU-XING

2013-01-01

113

Computed tomographic features of congenital left ventricular diverticulum.  

PubMed

Congenital left ventricular diverticulum is a rare cardiac malformation characterized by a localized out-pouching from the cardiac chamber. They are most often found in the left ventricle (LV) but have been reported to occur in all chambers of the heart. The patient is usually asymptomatic. However, complications like embolism, infective endocarditis, arrhythmia and, rarely, rupture may be the initial presentation. Diagnosis can be established by echocardiography (EKG), computed tomographic (CT) angiography, and magnetic resonance imaging (MRI). We report a case of congenital left ventricular diverticulum in an adult with no valvular abnormality as an incidental finding in an uncommon location. PMID:22919562

Dwivedi, Amit N D; Thangiah, Arun G; Rai, Madhukar; Tripathi, Suchi

2012-01-01

114

Left ventricular systolic asynchrony: an important sign for cardiac involvement in plaque-type psoriasis.  

PubMed

Psoriasis is associated with cardiovascular diseases (CVD). The purpose of this study was to evaluate the relationship between Left Ventricular (LV) asynchrony and psoriasis. Asynchrony was assessed in 31 patients with psoriasis without evidence of CVD and 25 healthy subjects. All the patients and controls were subjected to tissue synchronization imaging (TSI), and conventional and tissue Doppler echocardiography. The time to regional peak systolic tissue velocity (Ts) in LV by the six-basal-six-midsegmental model was measured on ejection phase TSI images, and four TSI parameters of systolic asynchrony were computed. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels in psoriatic patients were measured. All TSI parameters of LV asynchrony increased in psoriatic patients compared to the controls: the standard deviation (SD) of the 12 LV segments Ts (37.3 ± 14.8 vs. 24.6 ± 11.1, P = 0.002); the maximal difference in Ts between any two of the 12 LV segments (112.7 ± 39.8 vs. 83.1 ± 38.1, P = 0.01), the SD of the six basal LV segments (36.2 ± 17.3 vs. 23.2 ± 14.5, P = 0.008); and the maximal difference in Ts between any two of the six basal LV segments (91.3 ± 43.5 vs. 60.5 ± 37.3, P = 0.01). LV asynchrony was observed in 67.7% of psoriatic patients. Higher CRP (1.9 ± 1.3 vs. 0.92 ± 1.4, P = 0.04) and ESR (34.8 ± 17.3 vs. 20 ± 15.3, P = 0.03) levels were determined in patients with LV asynchrony. Regression analysis showed LV systolic asynchrony (P = 0.02), Tei index (P = 0.03), EF (P = 0.04), and E/A ratio (P = 0.04) were independently associated with psoriasis. LV asynchrony firstly described in patients with psoriasis may be an important finding of cardiac involvement in psoriasis. PMID:24320841

Örem, Cihan; Kazaz, Zeynep; Yayl?, Sava?; Çevik, Osman Ça?lar; K?r??, Abdulkadir; Öztürk, Mustafa; Arslan, Bilgihan; Örem, As?m

2014-03-01

115

Joint multi-object registration and segmentation of left and right cardiac ventricles in 4D cine MRI  

NASA Astrophysics Data System (ADS)

The diagnosis of cardiac function based on cine MRI requires the segmentation of cardiac structures in the images, but the problem of automatic cardiac segmentation is still open, due to the imaging characteristics of cardiac MR images and the anatomical variability of the heart. In this paper, we present a variational framework for joint segmentation and registration of multiple structures of the heart. To enable the simultaneous segmentation and registration of multiple objects, a shape prior term is introduced into a region competition approach for multi-object level set segmentation. The proposed algorithm is applied for simultaneous segmentation of the myocardium as well as the left and right ventricular blood pool in short axis cine MRI images. Two experiments are performed: first, intra-patient 4D segmentation with a given initial segmentation for one time-point in a 4D sequence, and second, a multi-atlas segmentation strategy is applied to unseen patient data. Evaluation of segmentation accuracy is done by overlap coefficients and surface distances. An evaluation based on clinical 4D cine MRI images of 25 patients shows the benefit of the combined approach compared to sole registration and sole segmentation.

Ehrhardt, Jan; Kepp, Timo; Schmidt-Richberg, Alexander; Handels, Heinz

2014-03-01

116

Unusual finding of cor triatriatum in a newborn with hypoplastic left heart syndrome  

Microsoft Academic Search

Cor triatriatum is a rare anomaly in which the left atrium is partitioned into 2 distinct chambers with a variable degree of obstruction to left atrial inflow. This anomaly often occurs in isolation but can occur in combination with other cardiac lesions. The association of cor triatriatum with hypoplastic left heart syndrome has not been reported. We describe a newborn

Benjamin W. Eidem; Frank Cetta

2001-01-01

117

Gated blood-pool SPECT versus cardiac magnetic resonance imaging for the assessment of left ventricular volumes and ejection fraction  

Microsoft Academic Search

Background  We evaluated the accuracy of planar radionuclide angiography and different count-based and space-based electrocardiogram (ECG)-gated\\u000a blood-pool single-photon emission computed tomography (GBPS) algorithms for assessment of left ventricular end-diastolic volume\\u000a (LVEDV), end-systolic volume (LVESV), and ejection fraction (LVEF) compared with the gold standard of cardiac magnetic resonance\\u000a imaging (cMRI). The goal is to assess the accuracy of a recently developed GBPS

François Harel; Vincent Finnerty; Jean Grégoire; Bernard Thibault; François Marcotte; Patricia Ugolini; Paul Khairy

2010-01-01

118

Left ventricular diastolic function in workers occupationally exposed to mercury vapour without clinical presentation of cardiac involvement  

SciTech Connect

The aim of the study was to evaluate left ventricular diastolic function in workers occupationally exposed to mercury vapour without clinical presentation of cardiac involvement. The studies included 115 workers (92 men and 23 women) occupationally exposed to mercury vapour without clinical presentation of cardiac involvement (mean age: 47.83 ± 8.29). Blood samples were taken to determine blood lipid profile, urine was collected to estimate mercury concentration (Hg-U) and echocardiographic examination was performed to evaluate diastolic function of the left ventricle. In the entire group of workers occupationally exposed to mercury vapour without clinical presentation of cardiac involvement, Spearman correlations analysis demonstrated the following significant linear relationships: between body mass index (BMI) and ratio of maximal early diastolic mitral flow velocity/early diastolic mitral annular velocity (E/E') (r = 0.32, p < 0.05), between serum HDL concentration and E/E' (r = ? 0.22, p < 0.05), between Hg-U and E/E' (r = 0.35, p < 0.05), between Hg-U and isovolumetric relaxation time (IVRT') (r = 0.41, p < 0.05), between Hg-U and ratio of maximal early diastolic mitral flow velocity/maximal late diastolic mitral flow velocity (E/A) (r = ? 0.31, p < 0.05) and between serum HDL concentration and E/A (r = 0.43, p < 0,05). In logistic regression analysis it as shown that independent factors of left ventricular diastolic dysfunction risk in the study group included a higher urine mercury concentration, a higher value of BMI and a lower serum HDL concentration (OR{sub Hg}-{sub U} = 1.071, OR{sub BMI} = 1.200, OR{sub HDL} = 0.896, p < 0.05). Summing up, occupational exposure to mercury vapour may be linked to impaired left ventricular diastolic function in workers without clinical presentation of cardiac involvement. -- Highlights: ? Study aimed at evaluation of LVDD in workers occupationally exposed to Hg. ? There was significant linear relationships between Hg-U and E/E'. ? Independent risk factor of LVDD in study group included higher Hg-U. ? Independent risk factor of LVDD in study group included higher BMI and lower HDL. ? Occupational exposure to Hg may be linked to LVDD.

Por?ba, Rafa?, E-mail: sogood@poczta.onet.pl; Skoczy?ska, Anna; Ga?, Pawe?; Turczyn, Barbara; Wojakowska, Anna

2012-09-15

119

Cardiac autonomic dysfunction in the early phase after left ventricular assist device implant: Implications for surgery and follow-up.  

PubMed

Purpose: In congestive heart failure (CHF) patients, a profound cardiac autonomic derangement, clinically expressed by reduced heart rate variability (HRV), is present and is related to the degree of ventricular dysfunction. Implantation of a left ventricular assist device (LVAD) can progressively improve HRV, associated with an increased circulatory output. Data from patients studied at different times after LVAD implantation are controversial. The aims of this study were to assess cardiac autonomic function in the early phases after axial-flow LVAD implantation, and to estimate the potential relevance of recent major surgical stress on the autonomic balance.?Methods: HRV (time-domain; 24-h Holter) was evaluated in 14 patients, 44.8 ± 25.8 days after beginning of Jarvik-2000 LVAD support; 47 advanced stage CHF, 24 cardiac surgery (CS) patients and ?30 healthy subjects served as control groups. Inclusion criteria: sinus rhythm, stable clinical conditions, no diabetes or other known causes of HRV alteration.?Results: HRV was considerably reduced in LVAD patients in the early phases after device implantation in comparison to all control groups. A downgrading of HRV parameters was also present in CS controls. Circadian oscillations were highly depressed in LVAD and CHF patients, and slightly reduced in CS patients.?Conclusions: In CHF patients supported by a continuous-flow LVAD, a profound cardiac dysautonomia is still evident in the first two months from the beginning of circulatory support; the degree of cardiac autonomic imbalance is even greater in comparison to advanced CHF patients. The recent surgical stress could be partly linked to these abnormalities. PMID:23645580

Compostella, Leonida; Russo, Nicola; Setzu, Tiziana; Tursi, Vincenzo; Bottio, Tomaso; Tarzia, Vincenzo; Compostella, Caterina; Covolo, Elisa; Livi, Ugolino; Gerosa, Gino; Sani, Guido; Bellotto, Fabio

2013-06-25

120

Protease-Activated Receptor 1 Inhibition by SCH79797 Attenuates Left Ventricular Remodeling and Profibrotic Activities of Cardiac Fibroblasts  

PubMed Central

Purpose Fibroblast activity promotes adverse left ventricular (LV) remodeling that underlies the development of ischemic cardiomyopathy. Transforming growth factor-? (TGF-?) is a potent stimulus for fibrosis, and the extracellular signal-regulated kinases(ERK) 1/2 pathway also contributes to the fibrotic response. The thrombin receptor, protease-activated receptor 1 (PAR1), has been shown to play an important role in the excessive fibrosis in different tissues. The aim of this study was to investigate the influence of a PAR1 inhibitor, SCH79797, on cardiac fibrosis, tissue stiffness and postinfarction remodeling, and effects of PAR1 inhibition on thrombin-induced TGF-? and (ERK) 1/2 activities in cardiac fibroblasts. Methods We used a rat model of myocardial ischemia–reperfusion injury, isolated cardiac fibroblasts, and 3-dimensional (3D) cardiac tissue models fabricated to ascertain the contribution of PAR1 activation on cardiac fibrosis and LV remodeling. Results The PAR1 inhibitor attenuated LV dilation and improved LV systolic function of the reperfused myocardium at 28 days. This improvement was associated with a nonsignificant decrease in scar size (%LV) from 23 ± % in the control group (n = 10) to 16% ± 5.5% in the treated group (n = 9; P = .052). In the short term, the PAR1 inhibitor did not rescue infarct size or LV systolic function after 3 days. The PAR1 inhibition abolished thrombin-mediated ERK1/2 phosphorylation, TGF-? and type I procollagen production, matrix metalloproteinase-2/9 activation, myofibroblasts transformation in vitro, and abrogated the remodeling of 3D tissues induced by chronic thrombin treatment. Conclusion These studies suggest PAR1 inhibition initiated after ischemic injury attenuates adverse LV remodeling through late-stage antifibrotic events.

Sonin, Dmitry L.; Wakatsuki, Tetsuro; Routhu, Kasi V.; Harmann, Leanne M.; Petersen, Matthew; Meyer, Jennifer; Strande, Jennifer L.

2013-01-01

121

Cardiac Magnetic Resonance Imaging After Stage I Norwood Operation for Hypoplastic Left Heart Syndrome  

Microsoft Academic Search

BCPC. Methods and Results—Cardiovascular MR and echocardiography were performed in 37 infants with hypoplastic left heart syndrome before BCPC, and the findings were compared with surgical findings. MR assessment of ventricular function and valvar regurgitation were compared with echocardiography. MR exhibited high sensitivity and specificity for identification of neoaortic (sensitivity 86%, specificity 97%) and left pulmonary artery (sensitivity 100%, specificity

Vivek Muthurangu; Andrew M. Taylor; Sanjeet R. Hegde; Robert Johnson; Robert Tulloh; John M. Simpson; Shakeel Qureshi; Eric Rosenthal; Edward Baker; David Anderson; Reza Razavi

2010-01-01

122

Electrical Wave Propagation in an Anisotropic Model of the Left Ventricle Based on Analytical Description of Cardiac Architecture  

PubMed Central

We develop a numerical approach based on our recent analytical model of fiber structure in the left ventricle of the human heart. A special curvilinear coordinate system is proposed to analytically include realistic ventricular shape and myofiber directions. With this anatomical model, electrophysiological simulations can be performed on a rectangular coordinate grid. We apply our method to study the effect of fiber rotation and electrical anisotropy of cardiac tissue (i.e., the ratio of the conductivity coefficients along and across the myocardial fibers) on wave propagation using the ten Tusscher–Panfilov (2006) ionic model for human ventricular cells. We show that fiber rotation increases the speed of cardiac activation and attenuates the effects of anisotropy. Our results show that the fiber rotation in the heart is an important factor underlying cardiac excitation. We also study scroll wave dynamics in our model and show the drift of a scroll wave filament whose velocity depends non-monotonically on the fiber rotation angle; the period of scroll wave rotation decreases with an increase of the fiber rotation angle; an increase in anisotropy may cause the breakup of a scroll wave, similar to the mother rotor mechanism of ventricular fibrillation.

Pravdin, Sergey F.; Dierckx, Hans; Katsnelson, Leonid B.; Solovyova, Olga; Markhasin, Vladimir S.; Panfilov, Alexander V.

2014-01-01

123

Automated quantification of cardiac short-axis multi-slice CT images for assessment of left ventricular global function  

NASA Astrophysics Data System (ADS)

This paper describes a method for automatic contour detection in reformatted short-axis (SA) cardiac computed tomography (CT) using a virtual exploring robot. The robot is a tricycle with a steering front wheel. Its motion obeys a set of kinematic equations and is subject to the non-holonomic constraints. The robot is designed to navigate in the binary representation of a cardiac image, consisting of the allowed navigational and obstacle spaces. It is initially positioned inside the allowed navigational space. Avoiding obstacles, the robot autonomously cruises through the navigational space and collects information about the location of the left ventricular (LV) boundaries. Consequently, the obtained information is used to reconstruct the endocardial and epicardial contours. Validation of the method was performed on in-vivo multislice multiphase short-axis cardiac CT images of ten subjects. Results showed good correlation between the quantitative parameters, computed from manual and automatic segmentation: for end-diastolic volume (EDV) r=0.99, for end-systolic volume (ESV) r=0.98, ejection fraction (EF) r=0.83, and LV mass (LVM) r=0.95.

Danilouchkine, Mikhail G.; Admiraal-Behloul, Faiza; van der Geest, Rob J.; Lelieveldt, Boudewijn P. F.; Reiber, Johan H. C.

2005-04-01

124

Stiffness of left ventricular cardiac fibroblasts is associated with ventricular dilation in patients with recent-onset nonischemic and nonvalvular cardiomyopathy.  

PubMed

Background:Ventricular dilation is known as a pivotal predictor in recent-onset cardiomyopathy (ROCM), but its pathophysiology is not fully understood. In the present study we investigated whether single-cell stiffness of right and left ventricular-derived fibroblasts has an effect on cardiac phenotype in patients with ROCM.Methods?and?Results:Patients with endomyocardial biopsy-proven ROCM were included (n=10). Primary cardiac fibroblasts (CFBs) were cultured from left and right ventricular endomyocardial biopsies and their single-cell stiffness was analyzed by quantification of Young's modulus using colloidal probe atomic force microscopy. Cardiac fibrosis was analyzed by Masson's trichrome staining. CFBs from the left ventricle showed significantly decreased stiffness when compared with CFBs from the right ventricle, indexed by decreased stiffness (Young's modulus 3,374±389 vs. 4,837±690 Pa; P<0.05). Young's modulus of CFBs derived from the left ventricle correlated negatively with the left ventricular end-diastolic dimension derived from 2-dimensional echocardiography (R(2)=0.77; P<0.01). Neither left nor right ventricular fibrosis correlated with the respective ventricular dimensions.Conclusions:Our data suggest that a decrease in single-cell stiffness of left ventricular fibroblasts could trigger left ventricular dilation in patients with ROCM. This implies a new potential mechanism for the ventricular dilation with this disease. (Circ J 2014; 78: 1693-1700). PMID:24899232

Glaubitz, Michael; Block, Stephan; Witte, Jeannine; Empen, Klaus; Gross, Stefan; Schlicht, Robert; Weitmann, Kerstin; Klingel, Karin; Kandolf, Reinhard; Hoffmann, Wolfgang; Gottschalk, Kay E; Busch, Mathias; Dörr, Marcus; Helm, Christiane A; Felix, Stephan B; Riad, Alexander

2014-06-25

125

A Voluntary Breath-Hold Treatment Technique for the Left Breast With Unfavorable Cardiac Anatomy Using Surface Imaging  

SciTech Connect

Purpose: Breath-hold (BH) treatments can be used to reduce cardiac dose for patients with left-sided breast cancer and unfavorable cardiac anatomy. A surface imaging technique was developed for accurate patient setup and reproducible real-time BH positioning. Methods and Materials: Three-dimensional surface images were obtained for 20 patients. Surface imaging was used to correct the daily setup for each patient. Initial setup data were recorded for 443 fractions and were analyzed to assess random and systematic errors. Real time monitoring was used to verify surface placement during BH. The radiation beam was not turned on if the BH position difference was greater than 5 mm. Real-time surface data were analyzed for 2398 BHs and 363 treatment fractions. The mean and maximum differences were calculated. The percentage of BHs greater than tolerance was calculated. Results: The mean shifts for initial patient setup were 2.0 mm, 1.2 mm, and 0.3 mm in the vertical, longitudinal, and lateral directions, respectively. The mean 3-dimensional vector shift was 7.8 mm. Random and systematic errors were less than 4 mm. Real-time surface monitoring data indicated that 22% of the BHs were outside the 5-mm tolerance (range, 7%-41%), and there was a correlation with breast volume. The mean difference between the treated and reference BH positions was 2 mm in each direction. For out-of-tolerance BHs, the average difference in the BH position was 6.3 mm, and the average maximum difference was 8.8 mm. Conclusions: Daily real-time surface imaging ensures accurate and reproducible positioning for BH treatment of left-sided breast cancer patients with unfavorable cardiac anatomy.

Gierga, David P., E-mail: dgierga@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Turcotte, Julie C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)] [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Sharp, Gregory C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States) [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States); Sedlacek, Daniel E.; Cotter, Christopher R. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)] [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Taghian, Alphonse G. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States) [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Boston, Massachusetts (United States)

2012-12-01

126

Evaluation of Left Ventricular Endocardial Cardiac Resynchronization Therapy in a Non-responder with Ventricular Arrhythmias.  

PubMed

Approximately one third of patients treated with cardiac resynchronization therapy do not derive any detectable benefit. In these patients, acute invasive hemodynamic evaluation can be used for therapy optimization. This report describes the use of systematic invasive hemodynamic measurements for clinical decision making in a patient who experienced severe ventricular arrhythmias and clinical deterioration following a biventricular upgrade. PMID:24493914

Mafi Rad, Masih; Blaauw, Yuri; Debie, Luuk; Rocca, Hans-Peter Brunner-La; Vernooy, Kevin

2014-01-01

127

Contrast-enhanced cardiac C-arm CT evaluation of radiofrequency ablation lesions in the left ventricle  

PubMed Central

Objectives The purpose of this study was to evaluate use of cardiac C-arm computed tomography (CT) in the assessment of the dimensions and temporal characteristics of radiofrequency ablation (RFA) lesions. This imaging modality uses a standard C-arm fluoroscopy system rotating around the patient, providing CT-like images during the RFA procedure. Background Both magnetic resonance imaging (MRI) and CT can be used to assess myocardial necrotic tissue. Several studies have reported visualizing cardiac RF ablation lesions with MRI, however obtaining MR images during interventional procedures is not common practice. Direct visualization of RFA lesions using C-arm CT during the procedure may improve outcomes and circumvent complications associated with cardiac ablation procedures. Methods RFA lesions were created on the endocardial surface of the left ventricle of 9 swine using a 7-F RF ablation catheter. An ECG-gated C-arm CT imaging protocol was used to acquire projection images during iodine contrast injection and following the injection every 5 min for up to 30 min, with no additional contrast. Reconstructed images were analyzed offline. The mean and standard deviation of the signal intensity of the lesion and normal myocardium were measured in all images in each time series. Lesion dimensions and area were measured and compared in pathologic specimens and C-arm CT images. Results All ablation lesions (n=29) were visualized and lesion dimensions, as measured on C-arm CT, correlated well with postmortem tissue measurements (1D dimensions : concordance correlation = 0.87; area : concordance correlation = 0.90). Lesions were visualized as a perfusion defect on first-pass C-arm CT images with a signal intensity 95 HU lower than normal myocardium (95% confidence interval: -111 to -79 HU). Images acquired at 1 and 5 minutes exhibited an enhancing ring surrounding the perfusion defect in 24 (83%) lesions. Conclusions RFA lesion size, including transmurality, can be assessed using ECG-gated cardiac C-arm CT in the interventional suite. Visualization of RFA lesions using cardiac C-arm CT may facilitate the assessment of adequate lesion delivery and provide valuable feedback during cardiac ablation procedures.

Girard, Erin E; Al-Ahmad, Amin A; Rosenberg, Jarrett; Luong, Richard; Moore, Teri; Lauritsch, Gunter; Boese, Jan; Fahrig, Rebecca

2011-01-01

128

Right aortic arch with isolation of the left innominate artery in a case of double chamber right ventricle and ventricular septal defect  

PubMed Central

Herein, we report an unusual case of right aortic arch with isolation of the left innominate artery in a case of double chamber right ventricle with ventricular septal defect. The blood supply to the innominate artery was by a collateral arising from the descending aorta. The embryological development of this anomaly can be explained by the hypothetical double aortic arch model proposed by Edwards with interruption of the arch at two levels.

Mangukia, Chirantan; Sethi, Sonali; Agarwal, Saket; Mishra, Smita; Satsangi, Deepak kumar

2014-01-01

129

Permanent epicardial and transvenous single- and dual-chamber cardiac pacing in children.  

PubMed

Between January 1974 and November 1991 33 children received a permanent single- or dual-chamber pacing system, mainly because of postoperative high-degree AV block. The children were followed up retrospectively for pacemaker- and lead-related complications, and for differences between epi- and endocardial stimulation. The overall rate of lead related complications was 35% and did not differ significantly between the epi- and endocardially paced groups, although it tended to be somewhat higher in the epicardially paced children, mainly due to a higher rate of exit blocks in the latter. The epicardially stimulated patients exhibited a significantly higher rate of pacemaker-related complications, which was primarily accounted for by a higher frequency of battery depletions in the epicardial systems. The most impressive differences between both groups, however, was seen with respect to subacute and chronic energy consumption. Chronic energy drain in the epicardially paced patients amounted to almost the sixfold of that seen in the endocardially stimulated children. This resulted in a significantly shorter cumulative pacemaker survival in the epicardial group. Therefore, it is concluded that, whenever possible, the transvenous approach be used in children and small infants too. However, as a rule, in the latter transvenous dualchamber pacing is usually not feasible. In these cases rate-adaptive single-chamber pacing has evolved as a reasonable alternative for improving hemodynamics as well as quality of life. In epicardial pacing the use of pulse generators allowing bidirectional telemetry is advisable. In this way monitoring of lead impedance and battery status can be performed noninvasively, thus permitting individualization of pulse widths and amplitude setting, which is important with respect to energy conservation. PMID:8367852

Esperer, H D; Singer, H; Riede, F T; Blum, U; Mahmoud, F O; Weniger, J

1993-02-01

130

Impact of microvascular obstruction and infarct size on left ventricular remodeling in reperfused myocardial infarction: a contrast-enhanced cardiac magnetic resonance imaging study  

Microsoft Academic Search

Infarct size (IS) and microvascular obstruction (MO) following ST-elevation myocardial infarction (STEMI) reperfusion may\\u000a affect left ventricular (LV) remodeling. We evaluated the impact of extent and transmurality of IS and MO in LV remodeling\\u000a using contrast-enhanced cardiac magnetic resonance imaging (MRI). Thirty-six consecutive patients presenting with a first\\u000a STEMI and undergoing contrast-enhanced cardiac MRI within 5 days of successful primary percutaneous

Antonella Lombardo; Giampaolo Niccoli; Luigi Natale; Antonio Bernardini; Nicola Cosentino; Lorenzo Bonomo; Filippo Crea

131

Patterns of left ventricular remodeling in patients with Duchenne Muscular Dystrophy: a cardiac MRI study of ventricular geometry, global function, and strain  

Microsoft Academic Search

The cardiac disease ubiquitously associated in Duchenne Muscular Dystrophy (DMD) has traditionally been considered a progressive\\u000a dilated cardiomyopathy (DCM). However, left ventricular (LV) dilatation as measured with cardiac MRI has not been a consistent\\u000a finding in this population, even as circumferential strain (?cc) declines with advancing disease. We hypothesized that a distinct pattern of changes in LV geometry, during the

Wojciech Mazur; Kan N. Hor; Joshua T. Germann; Robert J. Fleck; Hussein R. Al-Khalidi; Janaka P. Wansapura; Eugene S. Chung; Michael D. Taylor; John L. Jefferies; D. Woodrow Benson; William M. Gottliebson

132

Cardiac dose reduction with breathing adapted radiotherapy using self respiration monitoring system for left-sided breast cancer  

PubMed Central

Purpose To quantify the cardiac dose reduction during breathing adapted radiotherapy using Real-time Position Management (RPM) system in the treatment of left-sided breast cancer. Materials and Methods Twenty-two patients with left-sided breast cancer underwent CT scans during breathing maneuvers including free breathing (FB), deep inspiration breath-hold (DIBH), and end inspiration breath-hold (EIBH). The RPM system was used to monitor respiratory motion, and the in-house self respiration monitoring (SRM) system was used for visual feedback. For each scan, treatment plans were generated and dosimetric parameters from DIBH and EIBH plans were compared to those of FB plans. Results All patients completed CT scans with different breathing maneuvers. When compared with FB plans, DIBH plans demonstrated significant reductions in irradiated heart volume and the heart V25, with the relative reduction of 71% and 70%, respectively (p < 0.001). EIBH plans also resulted in significantly smaller irradiated heart volume and lower heart V25 than FB plans, with the relative reduction of 39% and 37%, respectively (p = 0.002). Despite of significant expansion of lung volume using inspiration breath-hold, there were no significant differences in left lung V25 among the three plans. Conclusion In comparison with FB, both DIBH and EIBH plans demonstrated a significant reduction of radiation dose to the heart. In the training course, SRM system was useful and effective in terms of positional reproducibility and patient compliance.

Sung, KiHoon; Lee, Seung Heon; Ahn, So Hyun; Lee, Seok Ho; Choi, Jinho

2014-01-01

133

[Isolated left ventricular congenital diverticulum in adult: Report of cardiac imaging].  

PubMed

Cardiac diverticulum is an infrequent congenital malformation, it's even more rare in adulthood. It's often associated with other thoraco-abdominal diverticulums, and rarely isolated. The diagnosis relies on echocardiography. By the way, the magnetic resonance imagery (MRI) allows a finer analysis of the diverticulum, its topography and its situation contributed to vascular and cardiac structures, it has largely replaced the ventriculography. We report in this article the case of a patient of 36 years whose diagnosis of the diverticulum was made by transthoracic echocardiography (TTE) at the time of an assessment of dyspnea, this exam also objectified a mitral insufficiency by deformation and dilatation of the mitral annulus. Radiological assessment was completed by a transoesophageal echocardiography (TOE) and magnetic resonance imagery (MRI). Surgical treatment consisted of surgical closing of the diverticulum and mitral annuloplasty. PMID:22436633

Bennis, K; Tamdy, A; Charif D'ouazzane, M; Assaidi, A; Doghmi, N; Allouch, M; Noureddine, M; Cherti, M; Bennis, A

2014-02-01

134

Sudden Cardiac Arrest in Patients with Preserved Left Ventricular Systolic Function: A Clinical Dilemma  

PubMed Central

Stratifying the risk for sudden cardiac arrest (SCA) in individuals with preserved systolic function remains a pressing public health problem. Current guidelines for the implantation of cardiac defibrillators largely ignore patients with preserved systolic function, even though they account for the majority of cases. However, risk stratification for such individuals is increasingly feasible. Notably, most individuals who experience SCA have structural heart disease, even if undiagnosed. Thus, clinical risk scores have been developed to identify high risk. Moreover, there are now promising data that T-Wave Alternans (TWA), alone and in combination with other indices, effectively predicts SCA in this population. This article presents our current understanding of SCA due to ventricular arrhythmias in patients with preserved LV systolic function, and attempts to build a framework to predict risk in this population.

Sawhney, Navinder; Narayan, Sanjiv M.

2009-01-01

135

Quantification of left ventricular mass using cardiac magnetic resonance imaging compared with echocardiography in domestic cats.  

PubMed

The hypotheses were that cardiac magnetic resonance imaging (cMRI) would accurately determine LV mass in domestic cats and would do so more accurately than echocardiography (ECHO). ECHO was performed on seven sedated cats. LV mass was calculated using the truncated ellipse formula from a right parasternal long-axis view. T1 weighted gradient echo cMRI was acquired from anesthetized cats during multiple phases of the cardiac cycle. Short-axis images were obtained by acquiring 3 mm thick contiguous slices perpendicular to the cardiac long axis. LV mass was determined using Simpson's rule. Endocardial and epicardial borders were traced on each slice at end-systole, end-diastole, and mid-cycle and the difference in areas was myocardial area. Myocardial area was multiplied by slice thickness to calculate myocardial volume. Total (summated) myocardial volume was multiplied by myocardial density (1.05) to obtain LV mass at three measured phases of the cardiac cycle. Cats were euthanized and the LV was dissected and weighed to determine true mass. CMRI at end-systole most accurately quantified LV mass and was more accurate than echocardiography (P = 0.0078). Actual LV mass ranged from 6.5 to 10.5 g (mean = 8.5 g, SD = 1.6 g) compared with MRI LV mass at end-systole, which ranged from 6.7 to 11.1 g (mean = 8.7 g, SD = 1.7 g) and echocardiographic LV mass at enddiastole, which ranged from 5.2 to 9.1 g (mean= 7.1 g, SD = 1.8 g). Inter- and intraobserver variability for cMRI was 2%. CMRI obtained at end-systole accurately and reliably quantifies LV mass in domestic cats. It is more accurate than the echocardiographic method used in this study. PMID:16050275

MacDonald, Kristin A; Kittleson, Mark D; Reed, Tracy; Larson, Richard; Kass, Philip; Wisner, Erik R

2005-01-01

136

Independent Value of Cardiac Troponin T and Left Ventricular Global Longitudinal Strain in Predicting All-Cause Mortality among Stable Hemodialysis Patients with Preserved Left Ventricular Ejection Fraction  

PubMed Central

Using a speckle-tracking echocardiography (STE), we recently demonstrated that a left ventricular (LV) global longitudinal strain (GLS) ? ?15% and the serum cardiac troponin T (cTnT) concentration are associated with mortality in stable hemodialysis patients with preserved LV ejection fraction (LVEF). In this study, we explored the relationship between cTnT and echocardiographic parameters and evaluated whether the prognostic value provided by cTnT is independent of a GLS ? ?15% and vice versa. Eighty-eight stable hemodialysis patients with preserved LVEF were followed for 31 months. STE studies and measurements of cTnT were performed at baseline. CTnT concentration had a modest correlation with GLS (rs = 0.44; P < 0.001) but had a weak or nonsignificant correlation with other echocardiographic parameters. Adjusting for clinical parameters, hazard ratios for each increase of 0.01?ng/mL in cTnT, and a GLS ? ?15% on mortality were 1.13 (P = 0.009) and 3.09 (P = 0.03) without significant interaction between cTnT and GLS ? ?15%. In addition, an increased cTnT concentration, a GLS ? ?15%, or their combination showed significant additional predictive value for mortality when included in models consisting of clinical parameters. Therefore, both cTnT and a GLS ? ?15% are independent predictors of mortality and are useful for risk stratification.

Su, Chi-Ting; Chang, Yu-Tzu; Wang, Saprina P. H.; Yang, Chun-Shin; Tsai, Liang-Miin; Chen, Jyh-Hong

2014-01-01

137

Independent Value of Cardiac Troponin T and Left Ventricular Global Longitudinal Strain in Predicting All-Cause Mortality among Stable Hemodialysis Patients with Preserved Left Ventricular Ejection Fraction.  

PubMed

Using a speckle-tracking echocardiography (STE), we recently demonstrated that a left ventricular (LV) global longitudinal strain (GLS) ? -15% and the serum cardiac troponin T (cTnT) concentration are associated with mortality in stable hemodialysis patients with preserved LV ejection fraction (LVEF). In this study, we explored the relationship between cTnT and echocardiographic parameters and evaluated whether the prognostic value provided by cTnT is independent of a GLS ? -15% and vice versa. Eighty-eight stable hemodialysis patients with preserved LVEF were followed for 31 months. STE studies and measurements of cTnT were performed at baseline. CTnT concentration had a modest correlation with GLS (r s = 0.44; P < 0.001) but had a weak or nonsignificant correlation with other echocardiographic parameters. Adjusting for clinical parameters, hazard ratios for each increase of 0.01?ng/mL in cTnT, and a GLS ? -15% on mortality were 1.13 (P = 0.009) and 3.09 (P = 0.03) without significant interaction between cTnT and GLS ? -15%. In addition, an increased cTnT concentration, a GLS ? -15%, or their combination showed significant additional predictive value for mortality when included in models consisting of clinical parameters. Therefore, both cTnT and a GLS ? -15% are independent predictors of mortality and are useful for risk stratification. PMID:24895553

Sung, Junne-Ming; Su, Chi-Ting; Chang, Yu-Tzu; Su, Yu-Ru; Tsai, Wei-Chuan; Wang, Saprina P H; Yang, Chun-Shin; Tsai, Liang-Miin; Chen, Jyh-Hong; Liu, Yen-Wen

2014-01-01

138

Automatic segmentation of the left ventricle from dual contrast cardiac MR data  

Microsoft Academic Search

Manual tracing of the blood pool from short axis cine MR images is routinely used to compute ejection fraction (EF) in clinical practice. The manual segmentation process is cumbersome, time consuming, and operator dependent. In this paper, we present an algorithm for the automatic computation of the EF that is based on segmenting the left ventricle by combining the fuzzy

A. Pednekar; I. A. Kakadiaris; R. Muthupillai; S. Flamm

2002-01-01

139

Impact of left ventricular assist device (LVAD) support on the cardiac reverse remodeling process  

Microsoft Academic Search

With improved technology and expanding indications for use, left ventricular assist devices (LVADs) are assuming a greater role in the care of patients with end-stage heart failure. Following LVAD implantation with the intention of bridge to transplant, it became evident that some patients exhibit substantial recovery of ventricular function. This prompted explantation of some devices in lieu of transplantation, the

Stefan Klotz; A. H. Jan Danser; Daniel Burkhoff

2008-01-01

140

Effect of sublingual nitroglycerin on cardiac performance in patients with coronary artery disease and non-dyskinetic left ventricular contraction.  

PubMed Central

In 8 patients with coronary artery disease and symmetrical left ventricular contraction, an echocardiographic study of left ventricular function was performed before and 3 minutes after the administration of 0-6 mg nitroglycerin sublingually. The left ventricular end-diastolic diameter decreased from 5-2 +/- 0-2 to 4-9 +/- 0-2 cm (P less than 0-05) and the end-systolic diameter from 4-2 +/- 0-2 to 3-7 +/- 0-2 cm (P less than 0-001). The estimated stroke volume did not change significantly, while the cardiac output increased, 5-8 +/- 0-6 to 7-7 +/- 0-6 l min-1 (P less than 0-001) and the heart rate increased from 72 +/- 5 to 90 +/- 6 (P less than 0-001). The mean arterial blood pressure decreased from 105 +/- 4 to 88 +/- 3 mmHg (P less than 0-001). The ejection fraction increased from 53 +/- 3 per cent to 65 +/- 6 per cent (P less than 0-001) and the mean velocity of circumferential fibre shortening (VCF) from 0-81 +/- 0-05 to 1-15 +/- 0-10 circumferences per second (P less than 0-001). The estimated midsystolic midwall stress decreased from 155 +/- 14 g cm-2 to 102 +/- 12 g cm-2 after mitroglycerin (P less than 0-001). The administration of nitroglycerin was associated with a significant decrease in left ventricular preload and afterload. A vasodilating effect is suggested by the fall in peripheral resistance. The overall improvement in ejection fraction and VCF may not reflect a true increase contractility, because of the concomitant fall in wall stress. Images

Hardarson, T; Wright, K E

1976-01-01

141

Radiation-induced cardiac damage in early left breast cancer patients: risk factors, biological mechanisms, radiobiology, and dosimetric constraints.  

PubMed

Today there is general awareness of the potential damage to the heart in left-sided (more than in right-sided) breast cancer radiotherapy (RT). Historical changes in tumor and heart doses are presented here along with the impact of different RT techniques and volumes. Individual and pharmacological risk factors are also examined with respect to radiation damage. The biological mechanisms of harm are only partially understood, such as the radiobiology of heart damage due to the presence of various radiosensitive structures and their topographic heterogeneity. Furthermore, individual variability may expose patients to higher or lower risks of late cardiac damage or death. Damage mechanisms and radiobiological characteristics in heart irradiation are presented in relation to dosimetric and biological parameters. PMID:22391054

Sardaro, Angela; Petruzzelli, Maria Fonte; D'Errico, Maria Patrizia; Grimaldi, Luca; Pili, Giorgio; Portaluri, Maurizio

2012-05-01

142

Comparison of QT Dispersion With Left Ventricular Mass Index in Early Diagnosis of Cardiac Dysfunction in Patients With ?-Thalassemia Major  

PubMed Central

Background: In electrocardiography (ECG), QT is the interval between the onset of Q wave to the end of the T wave. This interval may be a sign of changes in the ventricular structure in hematologic disorders such as thalassemia major. Objectives: The main goal of this study was to compare the diagnostic value of corrected QT dispersion (QTcd) and QT dispersion (QTd) with left ventricular mass (LVM) and left ventricular mass index (LVMI) as well as to determine their sensitivity and specificity in early detection of the cardiac involvement in patients with ?-thalassemia major. Patients and Methods: In a case-control study, 60 patients older than ten years of age with thalassemia major who received regular blood transfusion and iron chelators were selected as the case group and were compared with 60 healthy age- and sex-matched subjects. All patients had myocardial performance index (MPI) of more than 0.5 and MPI for controls was less than 0.5. Echocardiography and ECG were performed for both groups and data were analyzed using appropriate statistical tests. Results: The mean age of cases and controls were 16 ± 2.8 and 16.08 ± 3.01 years, respectively. Male to female ratio was 33:27 in case group and 31:29 in the control group. LVMI in the case group was greater than control group. QTd and QTcd were larger in case group than in control group. The sensitivity and specificity of LVM, LVMI, QTd, and QTcd were as follows: 88.3%, 77.1%; 86.7%, 80%; 93.8%, 80%; and 91.7%, 86.7%, respectively. Conclusions: This study showed acceptable sensitivity and specificity of QTcd and QTd in comparison to LVMI; it seems that standard ECG can be used for early diagnosis of cardiac involvement in asymptomatic patients with thalassemia major.

Noori, Noor Mohammad; Mahjoubifard, Maziar; Mohammadi, Mehdi; Jahangiri Fard, Alireza; Abassi, Abdolhossein; Farzanegan, Behrooz

2014-01-01

143

Improvement of Left Ventricular Function under Cardiac Resynchronization Therapy Goes along with a Reduced Incidence of Ventricular Arrhythmia  

PubMed Central

Objectives The beneficial effects of cardiac resynchronization therapy (CRT) are thought to result from favorable left ventricular (LV) reverse remodeling, however CRT is only successful in about 70% of patients. Whether response to CRT is associated with a decrease in ventricular arrhythmias (VA) is still discussed controversially. Therefore, we investigated the incidence of VA in CRT responders in comparison with non-responders. Methods In this nonrandomized, two-center, observational study patients with moderate-to-severe heart failure, LV ejection fraction (LVEF) ?35%, and QRS duration >120 ms undergoing CRT were included. After 6 months patients were classified as CRT responders or non-responders. Incidence of VA was compared between both groups by Kaplan-Meier analysis and Cox regression analysis. ROC analysis was performed to determine the aptitude of LVEF cut-off values to predict VA. Results In total 126 consecutive patients (64±11years; 67%male) were included, 74 were classified as responders and 52 as non-responders. While the mean LVEF at baseline was comparable in both groups (25±7% vs. 24±8%; P?=?0.4583) only the responder group showed an improvement of LVEF (36±6% vs. 24±7; p<0.0001) under CRT. In total in 56 patients VA were observed during a mean follow-up of 28±14 months, with CRT responders experiencing fewer VA than non-responders (35% vs. 58%, p<0.0061). Secondary preventive CRT implantation was associated with a higher likelihood of VA. As determined by ROC analysis an increase of LVEF by >7% was found to be a predictor of a significantly lower incidence of VA (AUC?=?0.606). Conclusions Improvement of left ventricular function under cardiac resynchronization therapy goes along with a reduced incidence of ventricular arrhythmia.

Eickholt, Christian; Siekiera, Marcus; Kirmanoglou, Kiriakos; Rodenbeck, Astrid; Heussen, Nicole; Schauerte, Patrick; Lichtenberg, Artur; Balzer, Jan; Rassaf, Tienush; Perings, Stefan; Kelm, Malte; Shin, Dong-In; Meyer, Christian

2012-01-01

144

A model-based time-reversal of left ventricular motion improves cardiac motion analysis using tagged MRI data  

PubMed Central

Background Myocardial motion is an important observable for the assessment of heart condition. Accurate estimates of ventricular (LV) wall motion are required for quantifying myocardial deformation and assessing local tissue function and viability. Harmonic Phase (HARP) analysis was developed for measuring regional LV motion using tagged magnetic resonance imaging (tMRI) data. With current computer-aided postprocessing tools including HARP analysis, large motions experienced by myocardial tissue are, however, often intractable to measure. This paper addresses this issue and provides a solution to make such measurements possible. Methods To improve the estimation performance of large cardiac motions while analyzing tMRI data sets, we propose a two-step solution. The first step involves constructing a model to describe average systolic motion of the LV wall within a subject group. The second step involves time-reversal of the model applied as a spatial coordinate transformation to digitally relax the contracted LV wall in the experimental data of a single subject to the beginning of systole. Cardiac tMRI scans were performed on four healthy rats and used for developing the forward LV model. Algorithms were implemented for preprocessing the tMRI data, optimizing the model parameters and performing the HARP analysis. Slices from the midventricular level were then analyzed for all systolic phases. Results The time-reversal operation derived from the LV model accounted for the bulk portion of the myocardial motion, which was the average motion experienced within the overall subject population. In analyzing the individual tMRI data sets, removing this average with the time-reversal operation left small magnitude residual motion unique to the case. This remaining residual portion of the motion was estimated robustly using the HARP analysis. Conclusion Utilizing a combination of the forward LV model and its time reversal improves the performance of motion estimation in evaluating the cardiac function.

Alrefae, Tareq; Smirnova, Irina V; Cook, Larry T; Bilgen, Mehmet

2008-01-01

145

Beat-to-beat estimation of the continuous left and right cardiac elastance from metrics commonly available in clinical settings  

PubMed Central

Introduction Functional time-varying cardiac elastances (FTVE) contain a rich amount of information about the specific cardiac state of a patient. However, a FTVE waveform is very invasive to directly measure, and is thus currently not used in clinical practice. This paper presents a method for the estimation of a patient specific FTVE, using only metrics that are currently available in a clinical setting. Method Correlations are defined between invasively measured FTVE waveforms and the aortic and pulmonary artery pressures from 2 cohorts of porcine subjects, 1 induced with pulmonary embolism, the other with septic shock. These correlations are then used to estimate the FTVE waveform based on the individual aortic and pulmonary artery pressure waveforms, using the “other” dysfunction’s correlations as a cross validation. Results The cross validation resulted in 1.26% and 2.51% median errors for the left and right FTVE respectively on pulmonary embolism, while the septic shock cohort had 2.54% and 2.90% median errors. Conclusions The presented method accurately and reliably estimated a patient specific FTVE, with no added risk to the patient. The cross validation shows that the method is not dependent on dysfunction and thus has the potential for generalisation beyond pulmonary embolism and septic shock.

2012-01-01

146

Improved relationship between left and right ventricular electrical activation after cardiac resynchronization therapy in heart failure patients can be quantified by body surface potential mapping  

PubMed Central

OBJECTIVES: Few studies have evaluated cardiac electrical activation dynamics after cardiac resynchronization therapy. Although this procedure reduces morbidity and mortality in heart failure patients, many approaches attempting to identify the responders have shown that 30% of patients do not attain clinical or functional improvement. This study sought to quantify and characterize the effect of resynchronization therapy on the ventricular electrical activation of patients using body surface potential mapping, a noninvasive tool. METHODS: This retrospective study included 91 resynchronization patients with a mean age of 61 years, left ventricle ejection fraction of 28%, mean QRS duration of 182 ms, and functional class III/IV (78%/22%); the patients underwent 87-lead body surface mapping with the resynchronization device on and off. Thirty-six patients were excluded. Body surface isochronal maps produced 87 maximal/mean global ventricular activation times with three regions identified. The regional activation times for right and left ventricles and their inter-regional right-to-left ventricle gradients were calculated from these results and analyzed. The Mann-Whitney U-test and Kruskall-Wallis test were used for comparisons, with the level of significance set at p?0.05. RESULTS: During intrinsic rhythms, regional ventricular activation times were significantly different (54.5 ms vs. 95.9 ms in the right and left ventricle regions, respectively). Regarding cardiac resynchronization, the maximal global value was significantly reduced (138 ms to 131 ms), and a downward variation of 19.4% in regional-left and an upward variation of 44.8% in regional-right ventricular activation times resulted in a significantly reduced inter-regional gradient (43.8 ms to 17 ms). CONCLUSIONS: Body surface potential mapping in resynchronization patients yielded electrical ventricular activation times for two cardiac regions with significantly decreased global and regional-left values but significantly increased regional-right values, thus showing an attenuated inter-regional gradient after the cardiac resynchronization therapy.

Samesima, Nelson; Pastore, Carlos Alberto; Douglas, Roberto Andres; Filho, Martino Martinelli; Pedrosa, Anisio A.

2013-01-01

147

Non-Invasive Parameters, Including a Low Left Ventricular Ejection Fraction, for Predicting Sudden Cardiac Death in Korean Post Myocardial Infarction Patients  

Microsoft Academic Search

Background and Objectives:According to the MADIT II criteria, a low left ventricular ejection fraction (LVEF) is one of the most important predicting factors for sudden cardiac death (SCD) in post myocardial infarction (PMI) patients, and it is a reasonable indication for ICD implantation. The aim of this study is to reveal the incidence and the prognostic value of the non-invasive

Jang-Won Sohn; Dong-Gu Shin; Dong-Hee Kim; Hyun-Soo Cho; Hyung-Jun Kim; Jun-Ho Bae; Geu-Ru Hong; Jong-Sun Park; Young-Jo Kim; Bong-Sub Shim

148

The use of extracorporeal life support in adult patients with primary cardiac failure as a bridge to implantable left ventricular assist device  

Microsoft Academic Search

Background. Extracorporeal life support (ECLS) is an effective technique for providing emergent circulatory assistance, and may represent a life-saving option in patients who might not initially be considered a candidate for other forms of circulatory support (extracorporeal or implantable left ventricular assist device [LVAD]). In the setting of cardiac arrest, ECLS represents the only viable method of initiating circulatory support.

Francis D Pagani; Keith D Aaronson; Fresca Swaniker; Robert H Bartlett

2001-01-01

149

Relations of diastolic left ventricular filling to systolic chamber and myocardial contractility in hypertensive patients with left ventricular hypertrophy (the PRESERVE study)  

Microsoft Academic Search

Abnormalities of left ventricular (LV) diastolic filling and stress-corrected midwall shortening (MWS) have been described in hypertensive patients with normal ejection fraction (EF). However, whether stress-corrected MWS parallels LV diastolic filling better than EF does remains uncertain. Blood pressure, body mass index, echocardiographic LV mass and LV geometry, EF and stress-corrected MWS, LV diastolic filling (peak E- and A-wave velocities,

Vittorio Palmieri; Jonathan N. Bella; Vincent DeQuattro; Mary J. Roman; Rebecca T. Hahn; Bjorn Dahlof; Norman Sharpe; Chu-Pak Lau; Wan-Chun Chen; Esther Paran; Giovanni de Simone; Richard B. Devereux

1999-01-01

150

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

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

151

Prediction of acute cardiac rejection by changes in left ventricular volumes  

SciTech Connect

Sixteen patients underwent heart transplantation (11 orthotopic, five heterotopic). Monitoring for acute rejection was by both endomyocardial biopsy (EMB) and multigated equilibrium blood pool scanning with technetium 99m-labelled red blood cells. From the scans information was obtained on left ventricular volumes (stroke, end-diastolic, and end-systolic), ejection fraction, and heart rate. Studies (208) were made in the 16 patients. There was a highly significant correlation between the reduction in stroke volume and end-diastolic volume (and a less significant correlation in end-systolic volume) and increasing acute rejection seen on EMB. Heart rate and ejection fraction did not correlate with the development of acute rejection. Correlation of a combination of changes in stroke volume and end-diastolic volume with EMB showed a sensitivity of 85% and a specificity of 96%. Radionuclide scanning is therefore a useful noninvasive tool for monitoring acute rejection.

Novitzky, D.; Cooper, D.K.; Boniaszczuk, J.

1988-11-01

152

Dipyridamole-thallium tests are predictive of severe cardiac arrhythmias in patients with left ventricular hypertrophy  

SciTech Connect

In a population of patients with chronic renal failure (CRF) and a high prevalence of left ventricular hypertrophy (LVH) undergoing chronic hemodialysis, the authors investigated the association between the results of dipyridamole-thallium tests (DTTs) and the occurrence of ventricular arrhythmias. They observed a positive significant association between positive DTTs and the occurrence of severe forms of ventricular arrhythmias. A significant association was also observed between the presence of severe LVH and the occurrence of severe ventricular arrhythmias. However, no association was found between the presence of LVH and the positivity of the DTT. As most of their patients with positive DTTs had unimpaired coronary circulations, they conclude that positive DTTs, although falsely indicative of impaired myocardial blood supply, does have an important clinical relevance, indicating increased risk of morbidity (and, possibly, mortality) due to ventricular arrhythmias in a population of CRF patients submitted to chronic renal function replacement program.

Saragoca, M.A.; Canziani, M.E.; Gil, M.A.; Castiglioni, M.L.; Cassiolato, J.L.; Barbieri, A.; Lima, V.C.; Draibe, S.A.; Martinez, E.E. (Cardiology Division, Escola Paulista de Medicina, Sao Paulo (Brazil))

1991-01-01

153

Atrium of stone: A case of confined left atrial calcification without hemodynamic compromise  

PubMed Central

Dystrophic cardiac calcification is often associated with conditions causing systemic inflammation and when present, is usually extensive, often encompassing multiple cardiac chambers and valves. We present an unusual case of dystrophic left atrial calcification in the setting of end stage renal disease on hemodialysis diagnosed by echocardiography and computed tomography. Significant calcium deposition is confined within the walls of the left atrium with no involvement of the mitral valve, and no hemodynamic effects.

Jones, Christopher; Lodhi, Aadil Mubeen; Cao, Long Bao; Chagarlamudi, Arjun Kumar; Movahed, Assad

2014-01-01

154

Vulnerable Myocardial Interstitium in Patients With Isolated Left Ventricular Hypertrophy and Sudden Cardiac Death: A Postmortem Histological Evaluation  

PubMed Central

Background Concentric left ventricular hypertrophy (LVH) is independently associated with increased risk of sudden cardiac death (SCD). Some animal models of LVH display specific alterations of the myocardial interstitium that could increase myocardial vulnerability to ventricular arrhythmias, but these merit evaluation in humans with LVH and SCD. Methods and Results Twelve consecutive patients with isolated LVH and SCD (LVH+SCD) in the absence of hypertrophic cardiomyopathy, coronary disease, or other cardiac structural abnormality were ascertained in the Oregon Sudden Unexpected Death Study. Detailed postmortem comparisons were conducted with 18 controls who had isolated LVH and unnatural deaths (Control Group A) and 6 controls who had structurally normal hearts and unnatural deaths (Control Group B). Postmortem left ventricular myocardial sections were obtained for measurement of collagen volume fraction, characterization of gap junctions, and quantification of collagen subtypes. Heart weight normalized to body weight was higher in LVH+SCD cases (6.9±1.2 g/kg) than in Control Group A (5.3±1.4 g/kg) and Control Group B (4.2±0.3 g/kg); P=0.001. Collagen volume fraction was also higher in LVH+SCD cases (3.1±0.4) than in Control Group A (2.3±0.4) and Control Group B (1.6±0.3); P=0.0002. The relative amount of collagen III was significantly higher in LVH+SCD cases (33.0±4.4%) than in Control Group A (20.9±4.3%) and Control Group B (13.4±3.5%); P=0.0001. There was an overall increase in the number of connexin 43–labeled gap junctions with increasing myocyte size. No subject was found to have high-risk hypertrophic cardiomyopathy mutations. Conclusions In addition to the expected increase in myocardial mass and overall collagen content, SCD with isolated LVH was associated with relative abundance of type III collagen, a novel finding that warrants further mechanistic evaluation. (J Am Heart Assoc. 2012;1:e001511 doi: 10.1161/JAHA.111.001511.)

Tamarappoo, Balaji K.; John, Benjamin T.; Reinier, Kyndaron; Teodorescu, Carmen; Uy-Evanado, Audrey; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S.

2012-01-01

155

Markov random field modeling for three-dimensional reconstruction of the left ventricle in cardiac angiography  

PubMed Central

This paper reports on a method for left ventricle three-dimensional reconstruction from two orthogonal ventriculograms. The proposed algorithm is voxel-based and takes into account the conical projection geometry associated with the biplane image acquisition equipment. The reconstruction process starts with an initial ellipsoidal approximation derived from the input ventriculograms. This model is subsequently deformed in such a way as to match the input projections. To this end, the object is modeled as a three-dimensional Markov-Gibbs random field, and an energy function is defined so that it includes one term that models the projections compatibility and another one that includes the space–time regularity constraints. The performance of this reconstruction method is evaluated by considering the reconstruction of mathematically synthesized phantoms and two 3-D binary databases from two orthogonal synthesized projections. The method is also tested using real biplane ventriculograms. In this case, the performance of the reconstruction is expressed in terms of the projection error, which attains values between 9.50% and 11.78 % for two biplane sequences including a total of 55 images.

Medina, Ruben; Garreau, Mireille; Toro, Javier; Le Breton, Herve; Coatrieux, Jean-Louis; Jugo, Diego

2006-01-01

156

Beneficial effects of sampatrilat, a novel vasopeptidase inhibitor, on cardiac remodeling and function of rats with chronic heart failure following left coronary artery ligation.  

PubMed

Sampatrilat is a novel vasopeptidase inhibitor that may offer a greater benefit than traditional angiotensin-converting enzyme (ACE) inhibitors in the treatment of chronic heart failure (CHF). The present study was undertaken to determine whether sampatrilat improves hemodynamic function and cardiac remodeling through a direct action on the failing heart in rats with CHF following left coronary artery ligation (CAL). Sampatrilat (30 mg/kg a day) was administered orally to the animals from the 1st to 6th week after the operation. Sampatrilat reduced the mortality of the rats with CAL (20 versus 57% for untreated rats). Treatment with sampatrilat for 5 weeks suppressed tissue ACE and neutral endopeptidase (NEP) activities. Sampatrilat did not affect the arterial blood pressure, whereas it attenuated the CAL-induced increases in the left ventricular end-diastolic pressure, heart weight, and collagen content of the viable left ventricle. To assess the direct effects of sampatrilat on collagen synthesis, we measured the incorporation of [(3)H]proline into cultured cardiac fibroblasts. Sampatrilat at concentrations that inhibited NEP activity in vitro augmented the atrial natriuretic peptide-induced decrease in [(3)H]proline incorporation by the cells. In addition, sampatrilat prevented the angiotensin I-induced increase in [(3)H]proline incorporation, whereas captopril did not. The results suggest that long-term treatment with sampatrilat regresses cardiac remodeling in rats with CAL, which is associated with improvement of hemodynamic function. The mechanism by which sampatrilat improved cardiac remodeling may be attributable to the direct inhibition of cardiac fibrosis, possibly acting through the cardiac natriuretic peptide system. PMID:12649357

Maki, Toshiyuki; Nasa, Yoshihisa; Tanonaka, Kouichi; Takahashi, Masaya; Takeo, Satoshi

2003-04-01

157

[Cardiac arrhythmias in hypertensive subjects with and without left ventricular hypertrophy compared to the circadian profile of the blood pressure].  

PubMed

To evaluate possible correlations between cardiac arrhythmias and circadian pattern of blood pressure (BP) and of heart rate (HR), we studied 2 groups of 20 males with stable arterial hypertension of mild to moderate entity, with (Group I) or without (Group II) left ventricular hypertrophy (LVH). In patients with LVH the mean age (56 vs 46 years), the duration of the hypertensive state (48.1 vs 15.7 months), the thickening of interventricular septum (IVS; 13.7 vs 9.6 mm) and of the posterior wall of the left ventricle (13.2 vs 9.2 mm) and the mass of LV (149.8 vs 99.7 g/m2) were significantly greater (p less than 0.01). On the contrary, the 2 groups did not show significant differences concerning casual BP determined in the morning (178.3/108.4 vs 171.5/106.2 mmHg). After a pharmacological washout of 2 weeks, patients underwent a noninvasive, intermittent, monitoring of BP (every 15 min during daytime and every 30 min from 11 pm to 7 am), using a pressure meter II Del Mar Avionics, and a continuous monitoring of ECG for 24 hours, employing an instrument 445/B Del Mar Avionics. Mean 24-hour BP was not different in the 2 groups of patients (161.7/99.0 vs 158.2/98.3 mmHg); however, patients with LVH showed a significantly greater variability of BP in the morning (7 am-3 pm), while mean 24-hour HR was significantly less (71.6 vs 78.2 b/min).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2150345

Novo, S; Barbagallo, M; Abrignani, M G; Alaimo, G; Longo, B; Corrao, S; Nardi, E; Liquori, M; Forte, G; Raineri, A

1990-08-01

158

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

PubMed

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. PMID:22021128

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

2012-05-01

159

Xanthine oxidase inhibition preserves left ventricular systolic but not diastolic function in cardiac volume overload.  

PubMed

Xanthine oxidase (XO) is increased in human and rat left ventricular (LV) myocytes with volume overload (VO) of mitral regurgitation and aortocaval fistula (ACF). In the setting of increased ATP demand, XO-mediated ROS can decrease mitochondrial respiration and contractile function. Thus, we tested the hypothesis that XO inhibition improves cardiomyocyte bioenergetics and LV function in chronic ACF in the rat. Sprague-Dawley rats were randomized to either sham or ACF ± allopurinol (100 mg·kg(-1)·day(-1), n ?7 rats/group). Echocardiography at 8 wk demonstrated a similar 37% increase in LV end-diastolic dimension (P < 0.001), a twofold increase in LV end-diastolic pressure/wall stress (P < 0.05), and a twofold increase in lung weight (P < 0.05) in treated and untreated ACF groups versus the sham group. LV ejection fraction, velocity of circumferential shortening, maximal systolic elastance, and contractile efficiency were significantly depressed in ACF and significantly improved in ACF + allopurinol rats, all of which occurred in the absence of changes in the maximum O2 consumption rate measured in isolated cardiomyocytes using the extracellular flux analyzer. However, the improvement in contractile function is not paralleled by any attenuation in LV dilatation, LV end-diastolic pressure/wall stress, and lung weight. In conclusion, allopurinol improves LV contractile function and efficiency possibly by diminishing the known XO-mediated ROS effects on myofilament Ca(2+) sensitivity. However, LV remodeling and diastolic properties are not improved, which may explain the failure of XO inhibition to improve symptoms and hospitalizations in patients with severe heart failure. PMID:24014679

Gladden, James D; Zelickson, Blake R; Guichard, Jason L; Ahmed, Mustafa I; Yancey, Danielle M; Ballinger, Scott; Shanmugam, Mayilvahanan; Babu, Gopal J; Johnson, Michelle S; Darley-Usmar, Victor; Dell'Italia, Louis J

2013-11-15

160

[The first experience with X-ray endovascular closure of the left atrial auricle using an Amplatzer Cardiac Plug in patients with atrial fibrillation].  

PubMed

Atrial fibrillation is the most common cardiac arrhythmia in clinical practice. Long-term anticoagulant therapy is used to prevent thrombosis in the left atrial (LA) auricle and, as a consequence, thrombolisms. However, some patients have contraindications to its use. The paper considers different alternative methods for preventing thromboembolic events and particularly one of the most common presently encountered ones - percutaneous transcatheter LA auricle excision, by applying the Amplatzer Cardiac Plug. There are also data on the authors' experience in using this device. PMID:23700919

Samko, A N; Merkulov, E V; Pevzner, D V; Guchaev, R V; Mironov, V M

2013-01-01

161

An Inverse Finite Element Method for Determining the Tissue Compressibility of Human Left Ventricular Wall during the Cardiac Cycle  

PubMed Central

The determination of the myocardium’s tissue properties is important in constructing functional finite element (FE) models of the human heart. To obtain accurate properties especially for functional modeling of a heart, tissue properties have to be determined in vivo. At present, there are only few in vivo methods that can be applied to characterize the internal myocardium tissue mechanics. This work introduced and evaluated an FE inverse method to determine the myocardial tissue compressibility. Specifically, it combined an inverse FE method with the experimentally-measured left ventricular (LV) internal cavity pressure and volume versus time curves. Results indicated that the FE inverse method showed good correlation between LV repolarization and the variations in the myocardium tissue bulk modulus K (K?=?1/compressibility), as well as provided an ability to describe in vivo human myocardium material behavior. The myocardium bulk modulus can be effectively used as a diagnostic tool of the heart ejection fraction. The model developed is proved to be robust and efficient. It offers a new perspective and means to the study of living-myocardium tissue properties, as it shows the variation of the bulk modulus throughout the cardiac cycle.

Hassaballah, Abdallah I.; Hassan, Mohsen A.; Mardi, Azizi N.; Hamdi, Mohd

2013-01-01

162

Quantitative description of the 3D regional mechanics of the left atrium using cardiac magnetic resonance imaging.  

PubMed

The left atrium (LA) plays an important role in the maintenance of hemodynamic and electrical stability of the heart. One of the conditions altering the atrial mechanical function is atrial fibrillation (AF), leading to an increased thromboembolic risk due to impaired mechanical function. Preserving the regions of the LA that contribute the greatest to atrial mechanical function during curative strategies for AF is important. The purpose of this study is to introduce a novel method of regional assessment of mechanical function of the LA. We used cardiac MRI to reconstruct the 3D geometry of the LA in nine control and nine patients with paroxysmal atrial fibrillation (PAF). Regional mechanical function of the LA in pre-defined segments of the atrium was calculated using regional ejection fraction and wall velocity. We found significantly greater mechanical function in anterior, septal and lateral segments as opposed to roof and posterior segments, as well as a significant decrease of mechanical function in the PAF group. We suggest that in order to minimize the impact of the AF treatment on global atrial mechanical function, damage related to therapeutic intervention, such as catheter ablation, in those areas should be minimized. PMID:24671140

Kuklik, P; Molaee, P; Podziemski, P; Ganesan, A N; Brooks, A G; Worthley, S G; Sanders, P

2014-05-01

163

Automatic Localization of the Left Ventricle from Cardiac Cine Magnetic Resonance Imaging: A New Spectrum-Based Computer-Aided Tool  

PubMed Central

Traditionally, cardiac image analysis is done manually. Automatic image processing can help with the repetitive tasks, and also deal with huge amounts of data, a task which would be humanly tedious. This study aims to develop a spectrum-based computer-aided tool to locate the left ventricle using images obtained via cardiac magnetic resonance imaging. Discrete Fourier Transform was conducted pixelwise on the image sequence. Harmonic images of all frequencies were analyzed visually and quantitatively to determine different patterns of the left and right ventricles on spectrum. The first and fifth harmonic images were selected to perform an anisotropic weighted circle Hough detection. This tool was then tested in ten volunteers. Our tool was able to locate the left ventricle in all cases and had a significantly higher cropping ratio of 0.165 than did earlier studies. In conclusion, a new spectrum-based computer aided tool has been proposed and developed for automatic left ventricle localization. The development of this technique, which will enable the automatic location and further segmentation of the left ventricle, will have a significant impact in research and in diagnostic settings. We envisage that this automated method could be used by radiographers and cardiologists to diagnose and assess ventricular function in patients with diverse heart diseases.

Zhong, Liang; Zhang, Jun-Mei; Zhao, Xiaodan; Tan, Ru San; Wan, Min

2014-01-01

164

Automatic localization of the left ventricle from cardiac cine magnetic resonance imaging: a new spectrum-based computer-aided tool.  

PubMed

Traditionally, cardiac image analysis is done manually. Automatic image processing can help with the repetitive tasks, and also deal with huge amounts of data, a task which would be humanly tedious. This study aims to develop a spectrum-based computer-aided tool to locate the left ventricle using images obtained via cardiac magnetic resonance imaging. Discrete Fourier Transform was conducted pixelwise on the image sequence. Harmonic images of all frequencies were analyzed visually and quantitatively to determine different patterns of the left and right ventricles on spectrum. The first and fifth harmonic images were selected to perform an anisotropic weighted circle Hough detection. This tool was then tested in ten volunteers. Our tool was able to locate the left ventricle in all cases and had a significantly higher cropping ratio of 0.165 than did earlier studies. In conclusion, a new spectrum-based computer aided tool has been proposed and developed for automatic left ventricle localization. The development of this technique, which will enable the automatic location and further segmentation of the left ventricle, will have a significant impact in research and in diagnostic settings. We envisage that this automated method could be used by radiographers and cardiologists to diagnose and assess ventricular function in patients with diverse heart diseases. PMID:24722328

Zhong, Liang; Zhang, Jun-Mei; Zhao, Xiaodan; Tan, Ru San; Wan, Min

2014-01-01

165

Cardiac troponin I for the prediction of functional recovery and left ventricular remodelling following primary percutaneous coronary intervention for ST-elevation myocardial infarction  

Microsoft Academic Search

ObjectiveTo 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).DesignPost hoc study extending from randomised controlled trial.Patients132 patients with STEMI receiving pPCI.Main outcome measuresLeft ventricular ejection fraction (LVEF), end-diastolic and end-systolic volume index (EDVI and ESVI) and changes in these parameters from

Jonas Hallén; Jesper K Jensen; Morten W Fagerland; Allan S Jaffe; Dan Atar

2010-01-01

166

An interesting case of cryptogenic stroke in a young man due to left ventricular non-compaction: role of cardiac MRI in the accurate diagnosis.  

PubMed

A 28-year-old man arrived for an outpatient cardiac MRI (CMR) study to evaluate cardiac structure. At the age of 24 the patient presented with acute onset expressive aphasia and was diagnosed with ischaemic stroke. Echocardiography at that time was reported as 'apical wall thickening consistent with apical hypertrophic cardiomyopathy'. CMR revealed a moderately dilated left ventricle with abnormal appearance of the left ventricular (LV) apical segments. Further evaluation was consistent with a diagnosis of LV non-compaction (LVNC) cardiomyopathy with a ratio of non-compacted to compacted myocardium measuring 3. There was extensive delayed hyperenhancement signal involving multiple segments representing a significant myocardial scar which is shown to have a prognostic role. Our patient, with no significant cerebrovascular risk factors, would likely have had an embolic stroke. This case demonstrates the role of CMR in accurately diagnosing LVNC in a patient with young stroke where prior echocardiography was non-diagnostic. PMID:24962593

Kannan, Arun; Das, Anindita; Janardhanan, Rajesh

2014-01-01

167

Association of ACE2 Genetic Variants With Blood Pressure, Left Ventricular Mass, and Cardiac Function in Caucasians With Type 2 Diabetes  

Microsoft Academic Search

BackgroundCardiovascular disease is common in diabetes, and is associated with activation of the renin–angiotensin system (RAS). Angiotensin-converting enzyme (ACE)2 is a recently described member of the RAS, and this study investigated whether ACE2 polymorphisms are associated with hypertension, left ventricular (LV) mass, and cardiac function in type 2 diabetes.MethodsVariants in ACE2 (rs1978124, rs2074192, rs4240157, rs4646156, rs4646188) were examined in 503

Sheila K. Patel; Bryan Wai; Michelle Ord; Richard J. MacIsaac; Sharon Grant; Elena Velkoska; Sianna Panagiotopoulos; George Jerums; Piyush M. Srivastava; Louise M. Burrell

2012-01-01

168

Evaluation of Cardiac Function Index as Measured by Transpulmonary Thermodilution as an Indicator of Left Ventricular Ejection Fraction in Cardiogenic Shock  

PubMed Central

Introduction. The PiCCO transpulmonary thermodilution technique provides two indices of cardiac systolic function, the cardiac function index (CFI) and the global ejection fraction (GEF). Both appear to be correlated with left ventricular ejection fraction (LVEF) measured by echocardiography in patients with circulatory failure, especially in septic shock. The aim of the present study was to test the reliability of CFI as an indicator of LVEF in patients with cardiogenic shock. Methods. In thirty-five patients with cardiogenic shock, we performed (i) simultaneous measurements of echocardiography LVEF and cardiac function index assessed by transpulmonary thermodilution (n = 72) and (ii) transpulmonary thermodilution before/after increasing inotropic agents (n = 18). Results. Mean LVEF was 31% (+/?11.7), CFI 3/min (+/?1), and GEF 14.2% (+/?6). CFI and GEF were both positively correlated with LVEF (P < 0.0001, r2 = 0.27). CFI and GEF were significantly increased with inotropic infusion (resp., P = 0.005, P = 0.007). A cardiac function index <3.47/min predicted a left ventricular ejection fraction ?35% (sensitivity 81.1% and specificity 63%). In patients with right ventricular dysfunction, CFI was not correlated with LVEF. Conclusion. CFI is correlated with LVEF provided that patient does not present severe right ventricular dysfunction. Thus, the PiCCO transpulmonary thermodilution technique is useful for the monitoring of inotropic therapy during cardiogenic shock.

Perny, Jessica; Perez, Pierre; Levy, Bruno

2014-01-01

169

Contrast between cardiac left ventricle and diaphragm muscle in expression of genes involved in carbohydrate and lipid metabolism.  

PubMed

The heart and diaphragm both need appropriate metabolic machinery to ensure long-term energy supplies, as they must contract rhythmically without cessation for the entire lifetime of the organism to ensure homeostasis of oxygen and carbon dioxide exchange. However, their energy requirements differ due to disparities in mechanical loads. Understanding how these two muscles converge and diverge in their approaches to meeting their metabolic demands may suggest novel strategies for improving cardiac and skeletal muscle long-term performance in health and disease. To assess this at a transcriptional level, expression of genes involved in carbohydrate and lipid metabolism was assessed using microarrays in rats. There were 594 genes with >2-fold differential expression between left ventricle of the heart and diaphragm; 307 were expressed heart>diaphragm and 287 diaphragm>heart. Assignment to gene ontology groups revealed over-representation for "carbohydrate metabolism" (P=0.005, n=32 genes or 5.4% of all genes with differential expression) and "lipid metabolism" (P=0.0012, n=48 genes or 8.1% of all genes with differential expression). For carbohydrate there were 14 genes with heart>diaphragm and 18 genes with diaphragm>heart, and for lipid there were 30 genes with heart>diaphragm and 18 genes with diaphragm>heart. The magnitude of differential expression between heart and diaphragm ranged up to 30-fold for carbohydrate and up to 59-fold for lipid. Carbohydrate-related genes were almost all involved in energy metabolism (e.g. Pfkm, Pgm1, Pgam1, Pfkfb1, Pfkfb2), whereas lipid-related genes were involved in energetics as well as other cellular processes; for both groups this included genes involved in rate-limiting metabolic steps. Data thus indicate that diaphragm and heart have both shared and differential transcriptional strategies for ensuring long-term energy supplies, with a relative favoring of lipid metabolism in the heart and carbohydrate metabolism in the diaphragm. PMID:18207466

van Lunteren, Erik; Spiegler, Sarah; Moyer, Michelle

2008-03-20

170

Characterization of Suitability of Coronary Venous Anatomy for Targeting Left Ventricular Lead Placement in Patients Undergoing Cardiac Resynchronization Therapy  

PubMed Central

Background: Differences in the quantity and distribution of coronary veins between patients with ischemic and nonischemic cardiomyopathy might affect the potential for the left ventricular (LV) lead targeting in patients undergoing cardiac resynchronization therapy (CRT). In the current study, we assessed and compared the suitability of the coronary venous system for the LV lead placement in ischemic and dilated cardiomyopathy. Methods: This single-centre study, performed at our hospital, retrospectively studied 173 patients with the New York Heart Association class III or IV who underwent CRT. The study population was comprised of 74 patients with an ischemic underlying etiology and 99 patients with a non-ischemic etiology. The distribution of the veins as well as the final lead positions was recorded. Results: There was no significant difference between the two groups in terms of the position of the available suitable vein with the exception of the posterior position, where the ischemic group had slightly more suitable veins than did the dilated group (48.4% versus 32.1%, p value = 0.049). There was also no significant difference with respect to the final vein, through which the LV lead was inserted. Comparative analysis showed that the patients with previous coronary artery bypass grafting surgery (CABG) had significantly fewer suitable veins in the posterolateral position than did the non-CABG group (16.3% versus 38.7%, p value = 0.029). There was, however, no significant difference between the two subgroups regarding the final vein position in which the leads were inserted. Conclusion: The final coronary vein position suitable and selected for the LV lead insertion was not different between the cases with cardiomyopathy with different etiologies, and nor was it different between the ischemic cases with and without a history of CABG. Patients with a history of procedures around the coronary vessel may have an intact or recovered venous system and may, therefore, benefit from transvenous LV lead placement for CRT.

Yaminisharif, Ahmad; Davoodi, Gholamreza; Kazemisaeid, Ali; Sadeghian, Saeed; Farahani, Ali Vasheghani; Yazdanifard, Parin; Sheikhvatan, Mehrdad; Shafiee, Akbar

2012-01-01

171

Relation of the ischaemic substrate to left ventricular remodelling by cardiac magnetic resonance at 1.5 T in rabbits  

PubMed Central

Objectives Contrast-enhanced cardiac magnetic resonance (CMR) for infarct sizing has been validated in large animals, but studies and follow-up are restricted. We sought to 1) validate CMR for assessment of myocardial area at risk (MAR) and infarct size (IS) in a rabbit model of reperfused myocardial infarction (MI); 2) analyse the relation between ischaemic substrates and subsequent left ventricular (LV) remodelling. Methods Experimental reperfused acute MI was induced in 16 rabbits. Ten animals underwent cross-registered cine and contrast-enhanced CMR and histopathology at day 3 for assessment of MAR and IS (group#1). The remaining 6 rabbits had serial CMR for the study of LV remodelling (group#2). Results In group#1, mean IS was 12.7±6.4% and 12.7±6.9% of total LV myocardial mass on CMR (late-enhancement technique) and histopathology (P=0.52; r=0.93). No significant difference occurred between CMR and histopathology for the calculation of MAR and IS/MAR ratio (P=0.18 and P=0.17), whereas correlations were strong (r=0.92 and r=0.95). In group#2, mean LV end-diastolic, end-systolic volumes and LV mass were significantly increased at 3 weeks compared with measurements at day 3 (P<0.01). Significant correlations between initial IS and the increase in LV end-diastolic volume (r=0.66) and the increase in LV mass (r=0.48) were observed, as well as correlations between initial MAR and the increase in LV end-diastolic volume (r=0.70) and the increase in LV mass (r=0.37). Conclusions Comprehensive CMR provides accurate assessment of IS and MAR in reperfused rabbit MI. Infarct size is closely related to LV remodelling. Through the infarct size/MAR ratio, this approach has great potential for assessing interventions aimed at cardioprotection.

Mansencal, Nicolas; Tissier, Renaud; Deux, Jean-Francois; Ghaleh, Bijan; Couvreur, Nicolas; Rienzo, Mario; Gueret, Pascal; Rahmouni, Alain; Berdeaux, Alain; Garot, Jerome

2010-01-01

172

Statistical agreement of left ventricle measurements using cardiac magnetic resonance and 2D echocardiography in ischemic heart failure  

PubMed Central

Summary Background The aim of this study was to compare cardiac magnetic resonance imaging (CMR) with 2-dimensional echocardiography (2D echo) in the assessment of left ventricle (LV) function parameters and mass in patients with ischemic heart disease and severely depressed LV function. Although 2D echo is commonly used to assess LV indices, CMR is the state-of-the-art technique. Agreement between these 2 methods in these patients has not been well established. Material/Methods LV indexed end systolic and diastolic volumes (EDVi and ESVi), indexed mass (LVMi) and ejection fraction (EF) were assessed in 67 patients (12 women), using 2D echo and CMR. Results According to statistical analysis (Bland-Altman), 2D echo underestimated LV EDV and ESV and overestimated EF and LVMi compared to CMR. The highest correlation between 2D echo and CMR was found for EDVi (R2=0.73, p<0.0001) and ESVi (R2=0.69, p<0.0001) and the lowest for EF (R2=0.21, p=0.001) and LVMi (R2=0.20, p=0.002). The maximal differences between 2D echo and CMR were found for highest mesurements of LV volumes and mass, and for lowest EF values. Conclusions There is moderate to strong correlation between CMR and 2D echo in the assessment of LV function parameters and mass in patients with ischemic heart failure. Between-method agreement depends on the degree of LV dysfunction. The results of assessment of the severely damaged LV obtained by the use of 2D echo should be interpreted with caution.

Gruszczynska, Katarzyna; Krzych, Lukasz J.; Golba, Krzysztof S.; Biernat, Jolanta; Roleder, Tomasz; Deja, Marek A.; Ulbrych, Piotr; Malinowski, Marcin; Janusiewicz, Piotr; Wos, Stanislaw; Baron, Jan

2012-01-01

173

High-sensitivity cardiac troponin T levels in newly diagnosed hypertensive patients with different left ventricle geometry.  

PubMed

Abstract Background. The high-sensitivity cardiac troponin T (hs-cTnT) assay provides important prognostic information on cardiovascular diseases. Although hs-cTnT is associated with left ventricle (LV) hypertrophy (LVH), it has not been investigated in different LV geometric patterns incorporating normal LV structure and concentric remodeling in addition to LVH. Objectives. We aimed to investigate the possible association between hs-cTnT and LV geometric patterns in newly diagnosed hypertensive patients. Methods. We studied 306 patients with newly diagnosed hypertension (HT; mean age 51.7 ± 5.6 years) and 44 healthy control subjects (mean age 51.3 ± 4.7 years). Echocardiographic examination was performed in all subjects. Four different geometric patterns were determined in hypertensive patients according to LV mass index (LVMI) and relative wall thickness (RWth). hs-cTnT and other biochemical markers were measured in all participants. Results. The highest hs-cTnT values were observed in the concentric hypertrophy group compared with the control, normal geometry, concentric remodeling and eccentric hypertrophy groups (p < 0.05, for all). Also, hs-cTnT values of the eccentric hypertrophy group were higher than the control, normal geometry and concentric remodeling groups (p < 0.05, for all). Multivariate regression analysis showed that hs-cTnT was independently associated with LV geometry (? = 0.326, p = 0.001) as well as LVMI (? = 0.228, p = 0.010) and creatinine level ? = 0.132, p = 0.012). Conclusion. hs-cTnT level is related not only to LVH but also to LV geometry in hypertensive patients. hs-cTnT levels may mediate poorer LV geometric patterns in hypertensive patients. PMID:24059745

Uçar, Hakan; Gür, Mustafa; Kivrak, Ali; Koyunsever, Nermin Yildiz; Seker, Taner; Akilli, Rabia Eker; Türko?lu, Caner; Kaypakli, Onur; Sahin, Durmu? Yildiray; Elbasan, Zafer; Tanbo?a, Halil ?brahim; Cayli, Murat

2014-08-01

174

Phenotyping of Left and Right Ventricular Function in Mouse Models of Compensated Hypertrophy and Heart Failure with Cardiac MRI  

PubMed Central

Background Left ventricular (LV) and right ventricular (RV) function have an important impact on symptom occurrence, disease progression and exercise tolerance in pressure overload-induced heart failure, but particularly RV functional changes are not well described in the relevant aortic banding mouse model. Therefore, we quantified time-dependent alterations in the ventricular morphology and function in two models of hypertrophy and heart failure and we studied the relationship between RV and LV function during the transition from hypertrophy to heart failure. Methods MRI was used to quantify RV and LV function and morphology in healthy (n?=?4) and sham operated (n?=?3) C57BL/6 mice, and animals with a mild (n?=?5) and a severe aortic constriction (n?=?10). Results Mice subjected to a mild constriction showed increased LV mass (P<0.01) and depressed LV ejection fraction (EF) (P<0.05) as compared to controls, but had similar RVEF (P>0.05). Animals with a severe constriction progressively developed LV hypertrophy (P<0.001), depressed LVEF (P<0.001), followed by a declining RVEF (P<0.001) and the development of pulmonary remodeling, as compared to controls during a 10-week follow-up. Myocardial strain, as a measure for local cardiac function, decreased in mice with a severe constriction compared to controls (P<0.05). Conclusions Relevant changes in mouse RV and LV function following an aortic constriction could be quantified using MRI. The well-controlled models described here open opportunities to assess the added value of new MRI techniques for the diagnosis of heart failure and to study the impact of new therapeutic strategies on disease progression and symptom occurrence.

van Nierop, Bastiaan J.; van Assen, Hans C.; van Deel, Elza D.; Niesen, Leonie B. P.; Duncker, Dirk J.; Strijkers, Gustav J.; Nicolay, Klaas

2013-01-01

175

Left Ventricular or Biventricular Pacing Improves Cardiac Function at Diminished Energy Cost in Patients With Dilated Cardiomyopathy and Left Bundle-Branch Block  

Microsoft Academic Search

Background—Left ventricular or biventricular pacing\\/stimulation can acutely improve systolic function in patients with dilated cardiomyopathy (DCM) and intraventricular conduction delay by resynchronizing contraction. Most heart failure therapies directly enhancing systolic function do so while concomitantly increasing myocardial oxygen consumption (MVO2). We hypothesized that pacing\\/stimulation, in contrast, incurs systolic benefits without raising energy demand. Methods and Results—Ten DCM patients with left

Gregory S. Nelson; Ronald D. Berger; Barry J. Fetics; Maurice Talbot; Julio C. Spinelli; Joshua M. Hare; David A. Kass

176

Increased rat cardiac angiotensin converting enzyme activity and mRNA expression in pressure overload left ventricular hypertrophy. Effects on coronary resistance, contractility, and relaxation.  

PubMed Central

We compared the activity and physiologic effects of cardiac angiotensin converting enzyme (ACE) using isovolumic hearts from male Wistar rats with left ventricular hypertrophy due to chronic experimental aortic stenosis and from control rats. In response to the infusion of 3.5 X 10(-8) M angiotensin I in the isolated buffer perfused beating hearts, the intracardiac fractional conversion to angiotensin II was higher in the hypertrophied hearts compared with the controls (17.3 +/- 4.1% vs 6.8 +/- 1.3%, P less than 0.01). ACE activity was also significantly increased in the free wall, septum, and apex of the hypertrophied left ventricle, whereas ACE activity from the nonhypertrophied right ventricle of the aortic stenosis rats was not different from that of the control rats. Northern blot analyses of poly(A)+ purified RNA demonstrated the expression of ACE mRNA, which was increased fourfold in left ventricular tissue obtained from the hearts with left ventricular hypertrophy compared with the controls. In both groups, the intracardiac conversion of angiotensin I to angiotensin II caused a comparable dose-dependent increase in coronary resistance. In the control hearts, angiotensin II activation had no significant effect on systolic or diastolic function; however, it was associated with a dose-dependent depression of left ventricular diastolic relaxation in the hypertrophied hearts. These novel observations suggest that cardiac ACE is induced in hearts with left ventricular hypertrophy, and that the resultant intracardiac activation of angiotensin II may have differential effects on myocardial relaxation in hypertrophied hearts relative to controls. Images

Schunkert, H; Dzau, V J; Tang, S S; Hirsch, A T; Apstein, C S; Lorell, B H

1990-01-01

177

Assessment of cardiac function using global and regional left ventricular endomyocardial and epimyocardial peak systolic strain and strain rate in healthy Labrador retriever dogs.  

PubMed

Speckle tracking echocardiography (STE) is based on tracking of natural acoustic myocardial markers. The study aimed at quantifying global and regional endomyocardial and epimyocardial left ventricular longitudinal, circumferential and radial peak systolic strain and strain rate, including feasibility and variability; and assessing synchronicity and torsion, in healthy dogs. Cineloops were acquired from left apical 4-chamber, basal and apical right parasternal short-axis views in 22 healthy Labrador retrievers. A general epimyocardial to endomyocardial strain gradient was found. Strain was higher at apex compared to base. A strain longitudinal base to apex gradient was found. Left ventricular synchronicity could be assessed in all dogs and torsion in 1/3. Short axis apical view had highest variability. Dog and operator contributed most to overall variance. In conclusion, STE allows assessment of myocardial function in healthy Labrador retrievers. A longitudinal base to apex gradient was found and a new synchronicity index for use in dogs was introduced. PMID:23481140

Carnabuci, C; Hanås, S; Ljungvall, I; Tidholm, A; Bussadori, C; Häggström, J; Höglund, K

2013-08-01

178

The effect of recombinant human growth hormone therapy on left-ventricular chamber size and function in children with growth hormone deficiency.  

PubMed

This study was designed to assess the effect of recombinant human growth hormone (rhGH) therapy on left-ventricular (LV) chamber size and function in children with idiopathic isolated growth hormone deficiency (GHD) using conventional echocardiography and tissue Doppler imaging (TDI). Thirty patients (19 boys and 11 girls) with idiopathic isolated GHD were followed-up for 12 months. Mean age of patients was 11.0 ± 2.6 years (range 6.3-15.5). At baseline and at 3, 6, and 12 months of treatment, the structure of the left ventricle was assessed by conventional echocardiography and myocardial rates and time intervals by TDI. There was a significant increase in LV mass (LVM) compared with pretreatment values. Like LVM, relative wall thickness (RWT) was also increased significantly. The significant increase in LVM indexed to body surface area and RWT became apparent at month 3 of treatment with a significant increase in LVM indexed to height(2.7) at treatment month 6. Normalized LVM increased as early month 3 of treatment, and a steady increase was observed until month 12. However, no patient had LVM > +2 standard deviation scores at month 12 of treatment. No significant differences were observed in functional parameters of the left ventricle and the interventricular septum. The results of this study showed that rhGH therapy causes an increase in myocardial mass without changing the geometry or function of the myocardium. Therefore, the increase in myocardial mass appears to be concentric, thus causing remodeling instead of hypertrophy. PMID:23760513

Esen, Ihsan; Cetin, Ilker; Demirel, Fatma; Ekici, Filiz

2013-12-01

179

Postmortem mRNA Expression Patterns in Left Ventricular Myocardial Tissues and Their Implications for Forensic Diagnosis of Sudden Cardiac Death  

PubMed Central

Sudden cardiac death (SCD), which is primarily caused by lethal heart disorders resulting in structural and arrhythmogenic abnormalities, is one of the prevalent modes of death in most developed countries. Myocardial ischemia, mainly due to coronary artery disease, is the most common type of heart disease leading to SCD. However, postmortem diagnosis of SCD is frequently complicated by obscure histological evidence. Here, we show that certain mRNA species, namely those encoding hemoglobin A1/2 and B (Hba1/2 and Hbb, respectively) as well as pyruvate dehydrogenase kinase 4 (Pdk4), exhibit distinct postmortem expression patterns in the left ventricular free wall of SCD subjects when compared with their expression patterns in the corresponding tissues from control subjects with non-cardiac causes of death. Hba1/2 and Hbb mRNA expression levels were higher in ischemic SCD cases with acute myocardial infarction or ischemic heart disease without recent infarction, and even in cardiac death subjects without apparent pathological signs of heart injuries, than control subjects. By contrast, Pdk4 mRNA was expressed at lower levels in SCD subjects. In conclusion, we found that altered myocardial Hba1/2, Hbb, and Pdk4 mRNA expression patterns can be employed as molecular signatures of fatal cardiac dysfunction to forensically implicate SCD as the primary cause of death.

Son, Gi Hoon; Park, Seong Hwan; Kim, Yunmi; Kim, Ji Yeon; Kim, Jin Wook; Chung, Sooyoung; Kim, Yu-Hoon; Kim, Hyun; Hwang, Juck-Joon; Seo, Joong-Seok

2014-01-01

180

Osteosarcoma of the lumbosacral spine invading the central venous pathways, right-sided cardiac chambers, and pulmonary artery.  

PubMed

We report an unusual case of lumbosacral osteogenic sarcoma with cauda equina syndrome and invasion into the central venous and cardiac system. A 41-year-old Hispanic man presented to the emergency department complaining of severe low back pain, cauda equina syndrome, bilateral lower extremity edema, and an extra heart sound on physical examination. CT of the lumbosacral spine done in the emergency department demonstrated a sclerotic lesion in the sacrum with cortical destruction, extension into the spinal canal and a bulky soft tissue mass containing calcifications. Supplemental MRI demonstrated marrow replacement of L4, L5, and the sacrum, soft tissue extension of the tumor, and invasion iliac veins extending into the IVC; however, the full extent of the intravascular tumor was not seen on this examination. Surgical laminectomy and biopsy of the spinal tumor provided the diagnosis of osteogenic sarcoma. A transthoracic echocardiogram was performed while the patient was recovering due to nonsustained ventricular tachycardia, which showed an echogenic mass within the right atrium and ventricle. CT pulmonary angiogram confirmed the echocardiogram showing a tumor extending through the pulmonary valve into the main pulmonary artery. The patient underwent en bloc resection of the tumor from the venous and cardiac systems. Histologic examination of the tumor confirmed osteogenic sarcoma. While vertebral osteogenic sarcoma is uncommon, invasion of the spinal canal is common in these tumors. However, tumor extending into the central venous and cardiac system is rare. The previously reported cases of central venous and cardiac involvement have been related to distant metastases or primary cardiac osteosarcomas. There is only one other reported case of direct extension into the venous system by an iliac bone osteosarcoma in an adolescent; however, the tumor did not extend into the pulmonary circulation. PMID:17618433

Hines, Neely; Lantos, George; Hochzstein, Jay; Gitig, Alon; DeAnda, Abe

2007-11-01

181

Left ventricular dysfunction with reduced functional cardiac reserve in diabetic and non-diabetic LDL-receptor deficient apolipoprotein B100-only mice  

PubMed Central

Background Lack of suitable mouse models has hindered the studying of diabetic macrovascular complications. We examined the effects of type 2 diabetes on coronary artery disease and cardiac function in hypercholesterolemic low-density lipoprotein receptor-deficient apolipoprotein B100-only mice (LDLR-/-ApoB100/100). Methods and results 18-month-old LDLR-/-ApoB100/100 (n = 12), diabetic LDLR-/-ApoB100/100 mice overexpressing insulin-like growth factor-II (IGF-II) in pancreatic beta cells (IGF-II/LDLR-/-ApoB100/100, n = 14) and age-matched C57Bl/6 mice (n = 15) were studied after three months of high-fat Western diet. Compared to LDLR-/-ApoB100/100 mice, diabetic IGF-II/LDLR-/-ApoB100/100 mice demonstrated more calcified atherosclerotic lesions in aorta. However, compensatory vascular enlargement was similar in both diabetic and non-diabetic mice with equal atherosclerosis (cross-sectional lesion area ~60%) and consequently the lumen area was preserved. In coronary arteries, both hypercholesterolemic models showed significant stenosis (~80%) despite positive remodeling. Echocardiography revealed severe left ventricular systolic dysfunction and anteroapical akinesia in both LDLR-/-ApoB100/100 and IGF-II/LDLR-/-ApoB100/100 mice. Myocardial scarring was not detected, cardiac reserve after dobutamine challenge was preserved and ultrasructural changes revealed ischemic yet viable myocardium, which together with coronary artery stenosis and slightly impaired myocardial perfusion suggest myocardial hibernation resulting from chronic hypoperfusion. Conclusions LDLR-/-ApoB100/100 mice develop significant coronary atherosclerosis, severe left ventricular dysfunction with preserved but diminished cardiac reserve and signs of chronic myocardial hibernation. However, the cardiac outcome is not worsened by type 2 diabetes, despite more advanced aortic atherosclerosis in diabetic animals.

2011-01-01

182

An induced pluripotent stem cell model of hypoplastic left heart syndrome (HLHS) reveals multiple expression and functional differences in HLHS-derived cardiac myocytes.  

PubMed

Hypoplastic left heart syndrome (HLHS) is a serious congenital cardiovascular malformation resulting in hypoplasia or atresia of the left ventricle, ascending aorta, and aortic and mitral valves. Diminished flow through the left side of the heart is clearly a key contributor to the condition, but any myocardial susceptibility component is as yet undefined. Using recent advances in the field of induced pluripotent stem cells (iPSCs), we have been able to generate an iPSC model of HLHS malformation and characterize the properties of cardiac myocytes (CMs) differentiated from these and control-iPSC lines. Differentiation of HLHS-iPSCs to cardiac lineages revealed changes in the expression of key cardiac markers and a lower ability to give rise to beating clusters when compared with control-iPSCs and human embryonic stem cells (hESCs). HLHS-iPSC-derived CMs show a lower level of myofibrillar organization, persistence of a fetal gene expression pattern, and changes in commitment to ventricular versus atrial lineages, and they display different calcium transient patterns and electrophysiological responses to caffeine and ?-adrenergic antagonists when compared with hESC- and control-iPSC-derived CMs, suggesting that alternative mechanisms to release calcium from intracellular stores such as the inositol trisphosphate receptor may exist in HLHS in addition to the ryanodine receptor thought to function in control-iPSC-derived CMs. Together our findings demonstrate that CMs derived from an HLHS patient demonstrate a number of marker expression and functional differences to hESC/control iPSC-derived CMs, thus providing some evidence that cardiomyocyte-specific factors may influence the risk of HLHS. PMID:24591732

Jiang, Yan; Habibollah, Saba; Tilgner, Katarzyna; Collin, Joseph; Barta, Tomas; Al-Aama, Jumana Yousuf; Tesarov, Lenka; Hussain, Rafiqul; Trafford, Andrew W; Kirkwood, Graham; Sernagor, Evelyne; Eleftheriou, Cyril G; Przyborski, Stefan; Stojkovi?, Miodrag; Lako, Majlinda; Keavney, Bernard; Armstrong, Lyle

2014-04-01

183

Malfunction of cardiac resynchronization therapy due to subsequent fracture of the ring and tip conductors of a co-radial left ventricular bipolar lead.  

PubMed

In two patients treated with cardiac resynchronization therapy (CRT), left ventricular (LV) pacing failure occurred due to ring conductor fractures of the bipolar LV lead (co-radial model). CRT was resumed by pacing between the tip conductor of the LV lead and the coil conductor of the right ventricular lead. However, shortly thereafter, subsequent fracture of the tip conductor developed, and implantation of a new LV lead was required. When one of the bipolar conductors of a co-radial designed LV lead fractures, reimplantation of a new LV lead is a better therapeutic option (than changing the LV pacing mode) in order to reliably continue CRT treatment. PMID:23728553

Sato, Akinori; Chinushi, Masaomi; Izumi, Daisuke; Furushima, Hiroshi; Minamino, Tohru

2013-01-01

184

Tako-tsubo-like left ventricular dysfunction with ST-segment elevation: A novel cardiac syndrome mimicking acute myocardial infarction  

Microsoft Academic Search

Background Peculiar asynergy, which consists of hypokinesis or akinesis from the mid portion to the apical area and hyperkinesis of the basal area on contrast left ventriculogram, is rare. Because the end-systolic left ventriculogram looks like a “tako-tsubo,” which was used for trapping octopuses in Japan, we proposed the term “tako-tsubo-like left ventricular dysfunction.” Our aim was to evaluate its

Satoshi Kurisu; Hikaru Sato; Takuji Kawagoe; Masaharu Ishihara; Yuji Shimatani; Kenji Nishioka; Yasuyuki Kono; Takashi Umemura; Suji Nakamura

2002-01-01

185

Kit-labeled technetium-99m red blood cells (Tc99mRBC's) for clinical cardiac chamber imaging  

Microsoft Academic Search

We have studied 223 consecutive patients by R-wave synchronized cardiac imaging using Tc-99m-RBC's labeled by the Brookhaven kit method. Preparation of the Tc-99m-RBC's is simple and can be accomplished in less than 20 min per patient. The average percent RBC labeling was 96.89%. Only 5 of 223 patients (2.2%) had yields less than 95%. Fifty patients were randomly selected from

Steven M. Larson; Glen W. Hamilton; Powell Richards; James L. Ritchie

1978-01-01

186

Long-term antihypertensive treatment fails to improve E/e' despite regression of left ventricular mass: an Anglo-Scandinavian cardiac outcomes trial substudy.  

PubMed

Antihypertensive treatment can improve tissue Doppler indices of left ventricular diastolic function in the short term, but little is known about the longer-term effect of different antihypertensive treatments on progression of left ventricular diastolic function and left ventricular hypertrophy. We hypothesized that long-term treatment of hypertension will lead to improvements in left ventricular hypertrophy and diastolic function. We collected detailed cardiovascular phenotypic data on 1006 participants from a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial. Patients randomized to either an amlodipine±perindopril-based or an atenolol±bendroflumethiazide-based regimen underwent conventional and tissue Doppler echocardiography at time of control of blood pressure after randomization (?1.5 years; phase 1) and after a further 2 years of antihypertensive treatment (phase 2). There were no prerandomization data. Five hundred thirty-six patients had complete data collection at both phases. Left ventricular mass index regressed from phase 1 to 2 with no significant difference between treatment groups (amlodipine: 119.5-116.8; atenolol: 122.9-117.5; P<0.001 for both). Conversely, tissue Doppler diastolic indices did not change in the amlodipine±perindopril-based regimen (E/e', 7.5-7.6 cm/s; P=not significant), but deteriorated in the atenolol±bendroflumethiazide-based regimen (E/e', 8.0-8.5 cm/s; P<0.01). Despite regression of left ventricular hypertrophy, there was no associated improvement in diastolic function. In fact, long-term treatment with atenolol±bendroflumethiazide resulted in a progressive deterioration in E/e'. This may be a factor contributing to the previously described worse clinical outcome in patients treated with atenolol±bendroflumethiazide compared with amlodipine±perindopril. PMID:24218432

Barron, Anthony J; Hughes, Alun D; Sharp, Andrew; Baksi, Arun J; Surendran, Praveen; Jabbour, Richard J; Stanton, Alice; Poulter, Neil; Fitzgerald, Des; Sever, Peter; O'Brien, Eoin; Thom, Simon; Mayet, Jamil

2014-02-01

187

Combined score using clinical, electrocardiographic, and echocardiographic parameters to predict left ventricular remodeling in patients having had cardiac resynchronization therapy six months earlier.  

PubMed

The aim of this study was to evaluate whether a scoring system integrating clinical, electrocardiographic, and echocardiographic measurements can predict left ventricular reverse remodeling after cardiac resynchronization therapy (CRT). The derivation cohort consisted of 162 patients with heart failure implanted with a CRT device. Baseline clinical, electrocardiographic, and echocardiographic characteristics were entered into univariate and multivariate models to predict reverse remodeling as defined by a ?15% reduction in left ventricular end-systolic volume at 6 months (60%). Combinations of predictors were then tested under different scoring systems. A new 7-point CRT response score termed L2ANDS2: Left bundle branch block (2 points), Age >70 years, Nonischemic origin, left ventricular end-diastolic Diameter <40 mm/m(2), and Septal flash (2 points) was calculated for these patients. This score was then validated against a validation cohort of 45 patients from another academic center. A highly significant incremental predictive value was noted when septal flash was added to an initial 4-factor model including left bundle branch block (difference between area under the curve C statistics = 0.125, p <0.001). The predictive accuracy using the L2ANDS2 score was then 0.79 for the C statistic. Application of the new score to the validation cohort (71% of responders) gave a similar C statistic (0.75). A score >5 had a high positive likelihood ratio (+LR = 5.64), whereas a score <2 had a high negative likelihood ratio (-LR = 0.19). In conclusion, this L2ANDS2 score provides an easy-to-use tool for the clinician to assess the pretest probability of a patient being a CRT responder. PMID:24793667

Brunet-Bernard, Anne; Maréchaux, Sylvestre; Fauchier, Laurent; Guiot, Aurélie; Fournet, Maxime; Reynaud, Amélie; Schnell, Frédéric; Leclercq, Christophe; Mabo, Philippe; Donal, Erwan

2014-06-15

188

Left Ventricular Trabeculae and Papillary Muscles: Correlation With Clinical and Cardiac Characteristics and Impact on Cardiovascular Magnetic Resonance Measures of Left Ventricular Anatomy and Function  

PubMed Central

Objective We sought to assess the relationship of left ventricular (LV) trabeculae and papillary muscles (TPM) with clinical characteristics in a community-based, free living adult cohort and to determine the effect of TPM on quantitative measures of LV volume, mass and ejection fraction (EF). Background Hypertrabeculation has been associated with adverse cardiovascular events, but the distribution and clinical correlates of the volume and mass of the TPM in a normal left ventricle have not been well characterized. Methods Short-axis cine cardiovascular magnetic resonance (CMR) images, obtained using a steady-state free precession sequence, from 1494 members of the Framingham Offspring cohort were analyzed using software that automatically segments TPM. Absolute TPM volume, TPM as a fraction of end-diastolic volume (TPM/EDV), and TPM mass as a fraction of LV mass (TPMm/LVM) were determined on all Offspring and in a referent group of Offspring free of clinical cardiovascular disease and hypertension. Results In the referent group (aged 61±9 years, with 262 men and 423 women) TPM was 23±3 % of LV EDV in both sexes (p=0.9). TPM/EDV decreased with age (p<0.02) but was not associated with body mass index (BMI). TPMm/LVM was inversely correlated with age (p<0.0001), BMI (p<0.018) and systolic blood pressure (p<0.0001). Among all 1494 participants (699 men) LV volumes decreased 23%, LV mass increased 28% and EF increased by 7.5 EF units (p<0.0001) when TPM were considered myocardial mass rather than part of the LV blood pool. Conclusions Global CMR LV parameters are significantly affected by whether TPM are considered as part of the LV blood pool or as part of LV mass. Our cross-sectional data from a healthy referent group of adults free of clinical cardiovascular disease demonstrate that TPM/EDV decreases with increasing age in both sexes, but is not related to hypertension or obesity.

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

2012-01-01

189

Balloon Venoplasty of Subclavian Vein and Brachiocephalic Junction to Enable Left Ventricular Lead Placement for Cardiac Resynchronisation Therapy  

PubMed Central

This report describes the successful implantation of a LV lead using balloon venoplasty to overcome a very tight stenosis of the right subclavian vein / brachiocephalic junction for cardiac resynchronisation therapy (CRT-P) in a patient with a right sided CRT-P system and a failed epicardial LV lead. It is important for device implanters to be familiar with interventional equipments and techniques such as balloon venoplasty to overcome difficult venous access.

Phan, Thanh Trung; James, Simon; Turley, Andrew

2013-01-01

190

Congenital circumflex coronary artery fistula with drainage into the left ventricle.  

PubMed Central

Congenital coronary fistula is a rare heart defect, which consists of a communication between a coronary artery and a cardiac chamber of coronary vessel. Most such fistulae drain into a right heart chamber or into the pulmonary artery. Congenital left coronary artery-left ventricle fistula is even more uncommon. In a search of the literature, we were able to find only 15 other cases of congenital left coronary artery-left ventricle fistula. We describe here the clinical picture of a patient with left circumflex coronary artery draining into the left ventricle, and the successful surgical repair of the lesion. As far as we know, such a case has never before been reported in detail. Images

Teno, L A; Santos, J L; Bestetti, R B; Zanardi, A M; Ceccon, C; Castilho, O T

1993-01-01

191

Isolation of the left atrial surface from cardiac multi-detector CT images based on marker controlled watershed segmentation  

Microsoft Academic Search

The delineation of left atrium (LA) and pulmonary veins (PVs) anatomy from high resolution images holds importance for atrial fibrillation (AF) investigation and treatment. In this study, a semiautomatic segmentation procedure for LA and PVs inner surface from contrast enhanced CT data was developed. The procedure consists of a three dimensional marker controlled watershed segmentation applied to the external morphological

Alessandro Cristoforetti; Luca Faes; Flavia Ravelli; Maurizio Centonze; Maurizio Del Greco; Renzo Antolini; Giandomenico Nollo

2008-01-01

192

INTRACORONARY ADMINISTRATION OF CARDIAC PROGENITOR CELLS ALLEVIATES LEFT VENTRICULAR DYSFUNCTION IN RATS WITH A 30-DAY OLD INFARCTION  

PubMed Central

Background Administration of cardiac progenitor cells (CPCs) 4 h after reperfusion ameliorates LV function in rats with acute myocardial infarction (MI). Clinically, however, this approach is not feasible because expansion of autologous CPCs after acute MI requires several weeks. Therefore, we determined whether CPCs are beneficial in the more clinically relevant setting of an old MI (scar). Methods and Results One month after coronary occlusion/reperfusion, rats received vehicle or EGFP-labeled CPCs intracoronarily. Thirty-five days later, CPC-treated rats exhibited more viable myocardium in the risk region, less fibrosis in the noninfarcted region, and improved LV function. EGFPpos cells expressing cardiomyocyte, endothelial, and vascular smooth muscle cell markers were observed only in 7/17 treated rats and occupied only 2.6% and 1.1% of risk and noninfarcted regions, respectively. Transplantation of CPCs was associated with increased proliferation and expression of cardiac proteins by endogenous CPCs. Conclusions Intracoronary administration of CPCs in the setting of an old MI produces beneficial structural and functional effects. Although exogenous CPCs can differentiate into new cardiac cells, this mechanism is not sufficient to explain the benefits, suggesting paracrine effects; among these, our data identify activation of endogenous CPCs. This is the first report that CPCs are beneficial in the setting of an old MI when given intracoronarily – the most widely applicable therapeutic approach in patients. Furthermore, this is the first evidence that exogenous CPC administration activates endogenous CPCs. These results open new therapeutic applications for use of autologous CPCs in patients with old MI and chronic ischemic cardiomyopathy.

Tang, Xian-Liang; Rokosh, Gregg; Sanganalmath, Santosh K.; Yuan, Fangping; Sato, Hiroshi; Mu, Jianyao; Dai, Shujing; Li, Chengxin; Chen, Ning; Peng, Yong; Dawn, Buddhadeb; Hunt, Greg; Leri, Annarosa; Kajstura, Jan; Tiwari, Sumit; Shirk, Gregg; Anversa, Piero; Bolli, Roberto

2010-01-01

193

Continuous cardiac output and left atrial pressure monitoring by long time interval analysis of the pulmonary artery pressure waveform: proof of concept in dogs.  

PubMed

We developed a technique to continuously (i.e., automatically) monitor cardiac output (CO) and left atrial pressure (LAP) by mathematical analysis of the pulmonary artery pressure (PAP) waveform. The technique is unique to the few previous related techniques in that it jointly estimates the two hemodynamic variables and analyzes the PAP waveform over time scales greater than a cardiac cycle wherein wave reflections and inertial effects cease to be major factors. First, a 6-min PAP waveform segment is analyzed so as to determine the pure exponential decay and equilibrium pressure that would eventually result if cardiac activity suddenly ceased (i.e., after the confounding wave reflections and inertial effects vanish). Then, the time constant of this exponential decay is computed and assumed to be proportional to the average pulmonary arterial resistance according to a Windkessel model, while the equilibrium pressure is regarded as average LAP. Finally, average proportional CO is determined similar to invoking Ohm's law and readily calibrated with one thermodilution measurement. To evaluate the technique, we performed experiments in five dogs in which the PAP waveform and accurate, but highly invasive, aortic flow probe CO and LAP catheter measurements were simultaneously recorded during common hemodynamic interventions. Our results showed overall calibrated CO and absolute LAP root-mean-squared errors of 15.2% and 1.7 mmHg, respectively. For comparison, the root-mean-squared error of classic end-diastolic PAP estimates of LAP was 4.7 mmHg. On future successful human testing, the technique may potentially be employed for continuous hemodynamic monitoring in critically ill patients with pulmonary artery catheters. PMID:19057003

Xu, Da; Olivier, N Bari; Mukkamala, Ramakrishna

2009-02-01

194

Normal left ventricular myocardial thickness for middle aged and older subjects with SSFP cardiac MR: The Multi-Ethnic Study of Atherosclerosis  

PubMed Central

Background Increased left ventricular myocardial thickness (LVMT) is a feature of several cardiac diseases. The purpose of this study was to establish standard reference values of normal LVMT with cardiac MR (CMR) and to assess variation with image acquisition plane, demographics and LV function. Methods and Results End-diastolic LVMT was measured on CMR steady-state free precession cine long and short axis images in 300 consecutive participants free of cardiac disease (169 women; 65.6±8.5 years) of the Multi-Ethnic Study of Atherosclerosis cohort. Mean LVMT on short axis images at the mid-cavity level was 5.3±0.9mm and 6.3±1.1mm for women and men, respectively. The average of the maximum LVMT at the mid-cavity for women/men were 7mm/9mm (long axis) and 7mm/8mm (short axis). Mean LVMT was positively associated with weight (0.02mm/kg, p=0.01) and body-surface-area (1.1mm/m2, p<0.001). No relationship was found between mean LVMT and age or height. Greater mean LVMT was associated with lower LV end-diastolic volume (0.01mm/ml, p<0.01), a lower LV end-systolic volume (?0.01mm/ml, p=0.01) and lower LV stroke volume (?0.01mm/ml, p<0.05). LVMT measured on long axis images at the basal and mid-cavity level were slightly greater (by 6% and 10%, respectively) than measurements obtained on short axis images; apical LVMT values on long axis images were 20% less than those on short axis images. Conclusion Normal values for wall thickness are provided for middle-aged and older subjects. Normal LVMT is lower for women than men. Observed values vary depending on the imaging plane for measurement.

Kawel, Nadine; Turkbey, Evrim B.; Carr, J. Jeffrey; Eng, John; Gomes, Antoinette S.; Hundley, W. Gregory; Johnson, Craig; Masri, Sofia C.; Prince, Martin R.; van der Geest, Rob J.; Lima, Joao A. C.; Bluemke, David A.

2012-01-01

195

Clinical features and usefulness of cardiac magnetic resonance imaging in assessing myocardial viability and prognosis in Takotsubo cardiomyopathy (transient left ventricular apical ballooning syndrome).  

PubMed

In Takotsubo cardiomyopathy, or transient left ventricular (LV) apical ballooning syndrome, normalization of wall motion can occur after as long as 3 months. We report 1 of the largest series to date outside Japan and emphasize the utility of cardiac magnetic resonance imaging (CMR) to show a lack of irreversible damage in the acute setting, thereby reliably predicting recovery. During the previous 6 years, we saw 22 patients who met the following criteria: (1) a suspected myocardial infarction based on symptoms, an abnormal electrocardiogram, and/or elevated serum cardiac markers; (2) an anteroapical wall motion abnormality; and (3) no significant occlusive epicardial coronary artery disease or observed vasospasm. Ten patients underwent delayed enhancement CMR to assess myocardial viability during the index presentation. All 10 patients had an absence of irreversible damage, as evidenced by lack of gadolinium "hyperenhancement"; later, their LV function returned to normal. Eight other patients, available for outpatient follow-up evaluation, also had normalization of LV function. Takotsubo cardiomyopathy is increasingly being recognized outside Japan and must be distinguished from acute myocardial infarction. In conclusion, CMR is useful to document segmental LV dysfunction and lack of irreversible damage and to predict functional recovery. PMID:17631086

Mitchell, James H; Hadden, Timothy B; Wilson, James M; Achari, Arup; Muthupillai, Raja; Flamm, Scott D

2007-07-15

196

Correlation of heart rate variability with cardiac functional and metabolic variables in cyclists with training induced left ventricular hypertrophy  

Microsoft Academic Search

OBJECTIVETo examine the correlation between heart rate variability and left ventricular mass in cyclists with an athlete’s heart.METHODSLeft ventricular mass and diastolic function were determined at rest and myocardial high energy phosphates were quantified at rest and during atropine–dobutamine stress in 12 male cyclists and 10 control subjects, using magnetic resonance techniques. Ambulatory 24 hour ECG recordings were obtained, and

B M Pluim; C A Swenne; A H Zwinderman; A C Maan; A van der Laarse; J Doornbos; E E Van der Wall

1999-01-01

197

Construction of a two-parameter empirical model of left ventricle wall motion using cardiac tagged magnetic resonance imaging data  

PubMed Central

Background A one-parameter model was previously proposed to characterize the short axis motion of the LV wall at the mid-ventricle level. The single parameter of this model was associated with the radial contraction of myocardium, but more comprehensive model was needed to account for the rotation at the apex and base levels. The current study developed such model and demonstrated its merits and limitations with examples. Materials and methods The hearts of five healthy individuals were visualized using cardiac tagged magnetic resonance imaging (tMRI) covering the contraction and relaxation phases. Based on the characteristics of the overall dynamics of the LV wall, its motion was represented by a combination of two components - radial and rotational. Each component was represented by a transformation matrix with a time-dependent variable ? or ?. Image preprocessing step and model fitting algorithm were described and applied to estimate the temporal profiles of ? and ? within a cardiac cycle at the apex, mid-ventricle and base levels. During this process, the tagged lines of the acquired images served as landmark reference for comparing against the model prediction of the motion. Qualitative and quantitative analyses were performed for testing the performance of the model and thus its validation. Results The ? and ? estimates exhibited similarities in values and temporal trends once they were scaled by the radius of the epicardium (repi)and plotted against the time scaled by the period of the cardiac cycle (Tcardiac) of each heart measured during the data acquisition. ?/repi peaked at about ?t/Tcardiac=0.4 and with values 0.34, 0.4 and 0.3 for the apex, mid-ventricle and base level, respectively. ?/repi similarly maximized in amplitude at about ?t/Tcardiac=0.4, but read 0.2 for the apex and - 0.08 for the base level. The difference indicated that the apex twisted more than the base. Conclusion It is feasible to empirically model the spatial and temporal evolution of the LV wall motion using a two-parameter formulation in conjunction with tMRI-based visualization of the LV wall in the transverse planes of the apex, mid-ventricle and base. In healthy hearts, the analytical model will potentially allow deriving biomechanical entities, such as strain, strain rate or torsion, which are typically used as diagnostic, prognostic or predictive markers of cardiovascular diseases including diabetes.

2012-01-01

198

Activated cranial cervical cord neurons affect left ventricular infarct size and the potential for sudden cardiac death.  

PubMed

To evaluate whether cervical spinal neurons can influence cardiac indices and myocyte viability in the acutely ischemic heart, the hearts of anesthetized rabbits subjected to 30 min of LAD coronary arterial occlusion (CAO) were studied 3h after reperfusion. Control animals were compared to those exposed to pre-emptive high cervical cord stimulation (SCS; the dorsal aspect of the C1-C2 spinal cord was stimulated electrically at 50 Hz; 0.2 ms; 90% of motor threshold, starting 15 min prior to and continuing throughout CAO). Four groups of animals were so tested: 1) neuroaxis intact; 2) prior cervical vagotomy; 3) prior transection of the dorsal spinal columns at C6; and 4) following pharmacological treatment [muscarinic (atropine) or adrenergic (atenolol, prazosin or yohimbine) receptor blockade]. Infarct size (IS) was measured by tetrazolium, expressed as percentage of risk zone. C1-C2 SCS reduced acute ischemia induced IS by 43%, without changing the incidence of sudden cardiac death (SCD). While SCS-induced reduction in IS was unaffected by vagotomy, it was no longer evident following transection of C6 dorsal columns or atropinization. Beta-adrenoceptor blockade eliminated ischemia induced SCD, while alpha-receptor blockade doubled its incidence. During SCS, myocardial ischemia induced SCD was eliminated following vagotomy while remaining unaffected by atropinization. These data indicate that, in contrast to thoracic spinal neurons, i) cranial cervical spinal neurons affect both adrenergic and cholinergic motor outflows to the heart such that ii) their activation modifies ventricular infarct size and lethal arrhythmogenesis. PMID:22502863

Southerland, E Marie; Gibbons, David D; Smith, S Brooks; Sipe, Adam; Williams, Carole Ann; Beaumont, Eric; Armour, J Andrew; Foreman, Robert D; Ardell, Jeffrey L

2012-07-01

199

Estimation of left ventricular end diastolic pressure (lvedp) in patients with ischemic heart disease by echocardiography and compare it with the results of cardiac catheterization  

PubMed Central

BACKGROUND Doppler echocardiography has been proposed as an appropriate non-invasive assay to estimate left ventricular end diastolic pressure (LVEDP). The aim of present research was to estimate the LVEDP in patients with ischemic heart disease by echocardiography and compare it with the results of cardiac catheterisation and to determine the effect of different echocardiographic variables on its measurement. METHODS In this descriptive-analytic study, patients with diagnosed ischemic heart disease were selected by nonrandomized sampling method. Selected population underwent M-mode and pulse doppler echocardiographic evaluation and parameters such as Q-Mitral valve E (Q-MVE), Q-Aortic valve closure (Q-AVC), Aortic valve closure-E (AVC-E), Q-Mitral valve closure/Aortic valve closure-E (Q-MVC/AVC-E), left ventricle-deceleration time (LV-DT), peak velocity-deceleration time (PV-DT) and A/E velocity time integral (A/E VTI) were evaluated. Immediately after echocardiography all patients underwent left heart catheterization for LVEDP measurement. The relation between different echocardiographic measurements and LVEDP, obtained by cardiac catheterization, was evaluated. RESULTS In this study, 47 patients with ischemic heart disease with mean age (±SD) of 53±13 were studied. There was a significant correlation between LVDEP and A/E VTI (r=0.44, P=0.001, and also between LVEDP and PV-DT in patients with A/E VTI ?1.1(r=?0.58, P=0.02). There was a significant correlation between LVEDP and Q-MVC/AVC-E in patients with LVEDP >18mmHg (r=0.76, P=0.03) and those with LVEDP ?18 mmHg and A/E VTI <1.1 (r=0.37, P=0.03). The correlation between LVEDP and A/E VTI was more significant in men, in patients aged >50 years with EF >55%, without LVH, without MR and those with coronary artery disease (P<0.05). CONCLUSION Some echocardiographic indices such as A/E VTI, Q-MVC/AVC-E and PV-DT are able to measure LVEDP especially in male patients aged >50 years, without LVH, without MR and those with coronary artery disease but it is necessary to determine specific conditions and factors affecting these indices, by further studies.

Sanei, Hamid; Tavassoli, Aliakbar; Shojaei, Mohammad

2011-01-01

200

Independent Predictors of Survival in Primary Systemic (AL) Amyloidosis, Including Cardiac Biomarkers and Left Ventricular Strain Imaging: An Observational Cohort Study  

PubMed Central

Background The prognostic value of Doppler myocardial imaging, including myocardial velocity imaging, strain, and strain rate imaging, in patients with primary (AL) amyloidosis is uncertain. The aim of this longitudinal study was to identify independent predictors of survival, comparing clinical data, hematologic and cardiac biomarkers, and standard echocardiographic and Doppler myocardial imaging measures in a cohort of patients with AL amyloidosis. Methods A total of 249 consecutive patients with AL amyloidosis were prospectively enrolled. The primary end point was all-cause mortality, and during a median follow-up period of 18 months, 75 patients (30%) died. Clinical and electrocardiographic data, biomarkers (brain natriuretic peptide and cardiac troponin T) and standard echocardiographic and longitudinal systolic and diastolic Doppler myocardial imaging measurements for 16 left ventricular segments were tested as potential independent predictors of survival. Results Age (hazard ratio [HR], 1.03; P = .03), New York Heart Association class III or IV (HR, 2.47; P = .01), the presence of pleural effusion (HR, 1.79; P = .08), brain natriuretic peptide level (HR, 1.29; P = .01), ejection time (HR, 0.99; P = .13), and peak longitudinal systolic strain of the basal anteroseptal segment (HR, 1.05; P = .02) were independent predictors in the final model. Conclusions Multivariate survival analysis identified independent predictors of clinical outcome in patients with AL amyloidosis: New York Heart Association class III or IV, presence of pleural effusion, brain natriuretic peptide level > 493 pg/mL, ejection time < 273 ms, and peak longitudinal systolic basal anteroseptal strain less negative than or equal to ?7.5% defined a high-risk group of patients.

Bellavia, Diego; Pellikka, Patricia A.; Al-Zahrani, Ghormallah B.; Abraham, Theodore P.; Dispenzieri, Angela; Miyazaki, Chinami; Lacy, Martha; Scott, Christopher G.; Oh, Jae K.; Miller, Fletcher A.

2014-01-01

201

Local electrogram delay recorded from left ventricular lead at implant predicts response to cardiac resynchronization therapy: Retrospective study with 1 year follow up  

PubMed Central

Background Considerable proportion of patients does not respond to the cardiac resynchronization therapy (CRT). This study investigated clinical relevance of left ventricular electrode local electrogram delay from the beginning of QRS (QLV). We hypothesized that longer QLV indicating more optimal lead placement in the late activated regions is associated with the higher probability of positive CRT response. Methods We conducted a retrospective, single–centre analysis of 161 consecutive patients with heart failure and LBBB or nonspecific intraventricular conduction delay (IVCD) treated with CRT. We routinely intend to implant the LV lead in a region with long QLV. Clinical response to CRT, left ventricular (LV) reverse remodelling (i.e. decrease in LV end-systolic diameter - LVESD ?10%) and reduction in plasma level of NT-proBNP >30% at 12-month post-implant were the study endpoints. We analyzed association between pre-implant variables and the study endpoints. Results Clinical CRT response rate reached 58%, 84% and 92% in the lowest (?105?ms), middle (106-130?ms) and the highest (>130?ms) QLV tertile (p?

2012-01-01

202

Left atrial and ventricular function during dobutamine and glycopyrrolate stress in healthy young and elderly as evaluated by cardiac magnetic resonance.  

PubMed

The aim of this study is to describe phasic volume changes of the left atrium (LA) in healthy young and elderly subjects at rest and during pharmacological stress (PS). LA maximum size is related to cardiovascular mortality. LA has passive, active, and conduit function for left ventricular (LV) filling. We hypothesized that changes in LV compliance from normal aging are reflected in LA volume changes and that PS will augment these differences. We enrolled twenty young (20-30 yr) and twenty elderly (60-70 yr) healthy subjects and measured their LV and LA volumes by cardiac magnetic resonance imaging at rest and during dobutamine and glycopyrrolate stress. We identified LA minimum, maximum, and middiastolic volumes and the volume before atrial contraction. LA emptying volumes were calculated as LA passive and active emptying volumes and LA conduit volume. We also calculated LV peak filling rates (LVPFRs). Both at rest and during PS, LA maximum and minimum volumes were similar in the groups, whereas middiastolic volume was higher in the elderly. During PS, a marked decrease in LA passive emptying function and a corresponding increase in LA active emptying function were seen in the elderly but not in the young. At rest, LVPFR was lower in the elderly, and during PS this difference was augmented. The aging heart has reduced LVPFR, which is reflected in reduced LA passive and compensatory increased LA active volumetric contribution to LV stroke volume. These age-related differences are evident at rest and highly augmented during both dobutamine and glycopyrrolate stress. PMID:23086990

Ahtarovski, Kiril A; Iversen, Kasper K; Lønborg, Jacob T; Madsen, Per L; Engstrøm, Thomas; Vejlstrup, Niels

2012-12-15

203

Cardiac responses to left ventricular pacing in hearts with normal electrical conduction: beneficial effect of improved filling is counteracted by dyssynchrony.  

PubMed

Cardiac resynchronization therapy (CRT) has been proposed in heart failure patients with narrow QRS, but the mechanism of a potential beneficial effect is unknown. The present study investigated the hypothesis that left ventricular (LV) pacing increases LV end-diastolic volume (LVEDV) by allowing the LV to start filling before the right ventricle (RV) during narrow QRS in an experimental model. LV and biventricular pacing were studied in six anesthetized dogs before and after the induction of LV failure. Function was evaluated by pressures and dimensions, and dyssynchrony was evaluated by electromyograms and deformation. In the nonfailing heart, LV pacing gave the LV a head start in filling relative to the RV (P < 0.05) and increased LVEDV (P < 0.05). The response was similar during LV failure when RV diastolic pressure was elevated. The pacing-induced increase in LVEDV was attributed to a rightward shift of the septum (P < 0.01) due to an increased left-to-right transseptal pressure gradient (P < 0.05). LV pacing, however, also induced dyssynchrony (P < 0.05) and therefore reduced LV stroke work (P < 0.05) during baseline, and similar results were seen in failing hearts. Biventricular pacing did not change LVEDV, but systolic function was impaired. This effect was less marked than with LV pacing. In conclusion, pacing of the LV lateral wall increased LVEDV by displacing the septum rightward, suggesting a mechanism for a favorable effect of CRT in narrow QRS. The pacing, however, induced dyssynchrony and therefore reduced LV systolic function. These observations suggest that detrimental effects should be considered when applying CRT in patients with narrow QRS. PMID:24906920

Boe, Espen; Russell, Kristoffer; Remme, Espen W; Gjesdal, Ola; Smiseth, Otto A; Skulstad, Helge

2014-08-01

204

Cardiac imaging in a patient with anomalous origin of the left coronary artery from the pulmonary artery--a case report.  

PubMed

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is an uncommon congenital heart disease and has a high mortality rate in infancy. However, myocardial ischemia does not develop until adolescence or adulthood in about 10% of patients. Moreover, the diagnosis of ALCAPA is often difficult in cases without heart murmur or cardiac symptoms. The authors report the case of a 31-year-old man with ALCAPA. He was admitted to the hospital for evaluation of mild shortness of breath at exercise, but he had no typical chest symptoms due to myocardial ischemia or heart failure until age 31 and he had no heart murmur. Moreover, electrocardiogram did not show an old myocardial infarction or myocardial ischemia. Therefore, the authors did not suspect ALCAPA until they performed transthoracic echocardiography and exercise-stress single photon emission computed tomography (SPECT) with Tc-99m-tetrofosmin. The final diagnosis was established from the results of coronary arteriography. In the present case, a transthoracic echocardiogram showed abnormal coronary circulation, and exercise-stress SPECT revealed reversible myocardial ischemia. Transthoracic echocardiography and myocardial SPECT imaging could be a useful noninvasive tools for diagnosing the ALCAPA. PMID:11512698

Noda, R; Sasao, H; Kyuma, M; Ichikawa, Y; Hasegawa, T; Endo, A; Oimatsu, H; Takada, T

2001-08-01

205

Use of a quadripolar left ventricular lead to achieve successful implantation in patients with previous failed attempts at cardiac resynchronization therapy  

PubMed Central

Aims Problems with implanting a left ventricular (LV) lead during cardiac resynchronization therapy (CRT) procedures are not uncommon and may occur for a variety of reasons including phrenic nerve stimulation (PNS) and high capture thresholds. We aimed to perform successful CRT in patients with previous LV lead problems using the multiple pacing configurations available with the St Jude Quartet model 1458Q quadripolar LV lead to overcome PNS or high capture thresholds. Methods and results Four patients with previous failed attempts at LV lead implantation underwent a further attempt at CRT using a Quartet lead. In all four cases, successful CRT was achieved using a Quartet lead placed in a branch of the coronary sinus. Problems with PNS or high capture thresholds were seen in all four patients but were successfully overcome. Satisfactory lead parameters were seen at implant, pre-discharge, and at short-term follow-up (8.5 ± 5 weeks). Conclusion The Quartet lead allows 10 different pacing vectors to be used and may overcome common pacing problems because of the multiple pacing configurations available. Problems with either PNS or unsatisfactory pacing parameters experienced during CRT may be resolved simply by changing the pacing configuration using this quadripolar lead system.

Shetty, Anoop K.; Duckett, Simon G.; Bostock, Julian; Rosenthal, Eric; Rinaldi, C. Aldo

2011-01-01

206

Serum High-Sensitivity Cardiac Troponin T Is a Significant Biomarker of Left-Ventricular Diastolic Dysfunction in Subjects with Non-Diabetic Chronic Kidney Disease  

PubMed Central

Background Chronic kidney disease (CKD) is associated with left-ventricular (LV) diastolic dysfunction (LVDD) which progresses to diastolic heart failure. However, biomarkers predicting LVDD in patients with CKD are largely unknown. Methods In 93 patients with non-diabetic CKD, the relationships among echocardiography, high-sensitivity cardiac troponin T (hs-cTnT), B-type natriuretic peptide (BNP), and renal function were evaluated. LV mass index, peak early diastolic mitral filling velocity (E), peak early diastolic mitral annular velocity (E?), and E/E? were recorded. Results The E? values were significantly decreased and E/E?, BNP, and hs-cTnT increased with increasing CKD stage. The CKD patients with LVDD with E? <5 cm/s had a significantly higher hs-cTnT level as well as a significantly higher BNP level compared to those with E? ?5 cm/s. The area under the receiver-operating characteristic curve for hs-cTnT and BNP to detect E? <5 cm/s was 0.880 (p = 0.0101) and 0.741 (p = 0.0570), respectively. In multivariate analysis, hs-cTnT and albuminuria were significantly associated with E?, and estimated glomerular filtration rate with the hs-cTnT level, after adjusting for age, cause of CKD, and other parameters. Conclusions These data suggest that hs-cTnT may be a useful biomarker of LVDD in non- diabetic CKD patients.

Kitagawa, Masashi; Sugiyama, Hitoshi; Morinaga, Hiroshi; Inoue, Tatsuyuki; Takiue, Keiichi; Kikumoto, Yoko; Uchida, Haruhito Adam; Kitamura, Shinji; Maeshima, Yohei; Toh, Norihisa; Nakamura, Kazufumi; Ito, Hiroshi; Makino, Hirofumi

2011-01-01

207

Functional cardiac imaging in coronary disease: increased sensitivity of first-pass radionuclide angiography utilizing sequential regional left ventricular early diastolic filling rate images.  

PubMed

In 127 patients, 113 with greater than or equal to 50% coronary artery stenosis (CAD), 14 with normal coronaries, cardiac catheterization and first-pass radionuclide angiography (RNA) utilizing left ventricular (LV) regional ejection fraction, first half systolic LV regional mean transit time and ejection rate images were performed. Additionally, the incremental value of a new technique, sequential regional LV filling rate images focusing on the first third of diastole, was established. Diastolic imaging improved RNA sensitivity from 88% (100/113) to 96% (109/113). Single vessel disease sensitivity increased from 77% (23/30) to 90% (27/30), whereas multivessel disease RNA positivity changed from 93% (77/83) to 99% (82/83). LAD system (LAD/D) sensitivity improved by 24% to 94% (79/84); RCA system (RCA/PDA) sensitivity increased 17% to 84% (59/70); circumflex system (CFX/OM) sensitivity was 83% (67/81), an improvement of 5%. Specificity was well maintained despite the increased sensitivity, as 86% (12/14) of patients with normal coronaries were normal by RNA. Furthermore, in the 113 CAD patients, 81% (84/104) of the vessels with insignificant or no stenosis were normal by RNA. We conclude sequential regional LV diastolic filling images substantially increase RNA sensitivity for CAD, while specificity is satisfactorily maintained. PMID:2376050

Murray, G L; Schad, N; Ladd, W; Stagg, J; Abben, R; Pharo, W; Walker, C; Vander-Zwagg, R

1990-01-01

208

Cardiac rhabdomyosarcoma.  

PubMed

Cardiac sarcoma is a very rare neoplasm and is difficult to diagnose. The case of a 51-year-old man with a left atrial tumour, locally recurrent three months after its surgical removal, is presented. Computed tomography showed metastatic spread to the lung parenchyma. On revised histology, the mass extirpated was a sarcoma. Because of the metastatic spread, further therapy was symptomatic only; the patient died 15 months after the first manifestation of his problems. Immunohistochemical staining confirmed cardiac rhabdomyosarcoma with metastatic spread to the lungs. Difficulty in diagnosing and treating cardiac tumours is discussed. PMID:20428274

Chlumský, J; Holá, D; Hlavácek, K; Michal, M; Svec, A; Spatenka, J; Dusek, J

2001-01-01

209

Flow chamber  

DOEpatents

A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

Morozov, Victor (Manassas, VA) [Manassas, VA

2011-01-18

210

Higher sympathetic nerve activity during ventricular (VVI) than during dual-chamber (DDD) pacing  

NASA Technical Reports Server (NTRS)

OBJECTIVES: We determined the short-term effects of single-chamber ventricular pacing and dual-chamber atrioventricular (AV) pacing on directly measured sympathetic nerve activity. BACKGROUND: Dual-chamber AV cardiac pacing results in greater cardiac output and lower systemic vascular resistance than does single-chamber ventricular pacing. However, it is unclear whether these hemodynamic advantages result in less sympathetic nervous system outflow. METHODS: In 13 patients with a dual-chamber pacemaker, we recorded the electrocardiogram, noninvasive arterial pressure (Finapres), respiration and muscle sympathetic nerve activity (microneurography) during 3 min of underlying basal heart rate and 3 min of ventricular and AV pacing at rates of 60 and 100 beats/min. RESULTS: Arterial pressure was lowest and muscle sympathetic nerve activity was highest at the underlying basal heart rate. Arterial pressure increased with cardiac pacing and was greater with AV than with ventricular pacing (change in mean blood pressure +/- SE: 10 +/- 3 vs. 2 +/- 2 mm Hg at 60 beats/min; 21 +/- 5 vs. 14 +/- 2 mm Hg at 100 beats/min; p < 0.05). Sympathetic nerve activity decreased with cardiac pacing and the decline was greater with AV than with ventricular pacing (60 beats/min -40 +/- 11% vs. -17 +/- 7%; 100 beats/min -60 +/- 9% vs. -48 +/- 10%; p < 0.05). Although most patients showed a strong inverse relation between arterial pressure and muscle sympathetic nerve activity, three patients with severe left ventricular dysfunction (ejection fraction < or = 30%) showed no relation between arterial pressure and sympathetic activity. CONCLUSIONS: Short-term AV pacing results in lower sympathetic nerve activity and higher arterial pressure than does ventricular pacing, indicating that cardiac pacing mode may influence sympathetic outflow simply through arterial baroreflex mechanisms. We speculate that the greater incidence of adverse outcomes in patients treated with single-chamber ventricular rather than dual-chamber pacing may be due in part to increased sympathetic nervous outflow.

Taylor, J. A.; Morillo, C. A.; Eckberg, D. L.; Ellenbogen, K. A.

1996-01-01

211

ST-segment resolution assessed immediately after primary percutaneous coronary intervention correlates with infarct size and left ventricular function in cardiac magnetic resonance at 1-year follow-up  

Microsoft Academic Search

BackgroundLittle is known about the predictive value of electrocardiographic ST-segment resolution (STR) assessed immediately after primary percutaneous coronary intervention (PCI). The aim of the study was to analyze the value of STR and maximum single-lead ST-segment elevation assessed immediately after primary PCI in prediction of infarct size and left ventricular function in cardiac magnetic resonance (CMR) at 1-year follow-up.

Tomasz Rakowski; Artur Dziewierz; Zbigniew Siudak; Waldemar Mielecki; Agata Brzozowska-Czarnek; Jacek Legutko; Lukasz Rzeszutko; Andrzej Urbanik; Jacek S. Dubiel; Dariusz Dudek

2009-01-01

212

Left ventricular diastolic function in type 2 diabetes mellitus and the association with coronary artery calcium score: a cardiac MRI study.  

PubMed

OBJECTIVE. The purpose of this study was to compare cardiac MRI-derived parameters of left ventricular (LV) diastolic function between uncomplicated type 2 diabetes mellitus (DM2) and normoglycemic control subjects and to evaluate whether these parameters of LV diastolic function are related to coronary atherosclerosis. SUBJECTS AND METHODS. We prospectively studied 41 subjects with DM2 and 21 normoglycemic control subjects (30 women and 32 men; mean age, 57.2 ± 7.1 [SD] years) with no evidence of overt cardiovascular disease. We used cardiac MRI to measure LV volumes, LV peak filling rate (PFR), and transmitral flow and CT to determine coronary artery calcium scores. RESULTS. Absolute values of the peak filling rate (PFR) were significantly lower in DM2 patients than in control subjects (mean ± SD, 293.2 ± 51.7 vs 375.7 ± 102.8 mL/s, respectively; p < 0.001). Mitral peak E velocities (mean ± SD, 42.8 ± 10.7 vs 48.8 ± 10.4 cm/s; p = 0.040) and peak E velocity-to-peak A velocity ratios (0.88 ± 0.3 vs 1.1 ± 0.3; p = 0.002) were also lower in DM2 patients compared with control subjects. DM2 patients with coronary artery calcification showed a lower PFR normalized to stroke volume (SV) (mean ± SD, 4.4 ± 1.0 vs 5.3 ± 1.4, respectively; p = 0.038) and lower mitral peak E velocities (40.1 ± 11.3 vs 48.0 ± 7.3 cm/s; p = 0.024) than DM2 patients without coronary calcification. PFR normalized to SV was independently associated with the presence of coronary artery calcification (? = -1.5, p = 0.005). CONCLUSION. DM2 decreases cardiovascular MRI-derived parameters of LV diastolic function. Patients with DM2 and coronary atherosclerosis show a more impaired LV diastolic function than patients without coronary atherosclerosis. PMID:24848817

Graça, Bruno; Donato, Paulo; Ferreira, Maria João; Castelo-Branco, Miguel; Caseiro-Alves, Filipe

2014-06-01

213

Reduced coronary blood flow in cardiac tamponade: mystery solved.  

PubMed

A 67-year-old male presented with several week history of progressive shortness of breath, lower extremity edema, and distended jugular veins. Transthoracic echocardiography showed moderate pericardial effusion with thickened visceral pericardium and septal bounce but no chamber collapse. Right and left cardiac catheterization showed discordance of the right and left ventricular systolic pressures during respiration and severely reduced cardiac output. There was near equalization of diastolic pressures in all four chambers suggestive of effusive-constrictive pericarditis with cardiac tamponade physiology. Simultaneous coronary angiography showed remarkably reduced coronary Thrombolysis in Myocardial Infarction (TIMI) flow (TIMI grade 2 flow). Coronary blood flow was restored to normal after pericardial drainage on repeat coronary angiography. This is the first report of reduced coronary blood flow on coronary angiography in patients with effusive-constrictive pericarditis and cardiac tamponade. Our finding complements the work of previous investigators as we show that elevated intrapericardial pressures in cardiac tamponade can reduce coronary blood flow. This is likely related to extrinsic epicardial coronary vessel compression and reduced perfusion pressures, which can lead to myocardial ischemia and eventually cardiogenic shock. PMID:23220996

Abusaid, Ghassan H; Khalife, Wissam I

2012-12-01

214

Magnitude and Time Course of Changes Induced by Continuous-Flow Left Ventricular Assist Device Unloading in Chronic Heart Failure: Insights into Cardiac Recovery  

PubMed Central

Objective To prospectively investigate the longitudinal effects of continuous-flow left ventricular assist device (LVAD) unloading on myocardial structure and systolic and diastolic function. Background The magnitude, timeline and sustainability of changes induced by continuous-flow LVAD on the structure and function of the failing human heart are unknown. Methods Eighty consecutive patients with clinical characteristics consistent with chronic heart failure requiring implantation of a continuous-flow LVAD were prospectively enrolled. Serial echocardiograms (1, 2, 3, 4, 6, 9 and 12 months) and right heart catheterizations were performed after LVAD implant. Cardiac recovery was assessed on the basis of improvement in systolic and diastolic function indices on echocardiography that were sustained during LVAD turn-down studies. Results After 6 months of LVAD unloading, 34% of patients had a relative LVEF increase above 50% and 19% of patients, both ischemic and nonischemic, achieved an LVEF?40%. LV systolic function improved as early as 30 days, the greatest degree of improvement was achieved by 6 months of mechanical unloading and persisted over the 1- year follow up. LV diastolic function parameters also improved as early as 30 days post LVAD unloading and this improvement persisted over time. LV end-diastolic and end-systolic volumes decreased as early as 30 days post LVAD unloading (113 vs. 77ml/m2, p<0.01 and 92 vs. 60ml/m2, p<0.01, respectively). LV mass decreased as early as 30 days post LVAD unloading (114 vs. 95g/m2, p<0.05) and continued to do so over the 1-year follow-up but did not reach values below the normal reference range suggesting no atrophic remodeling after prolonged LVAD unloading. Conclusion Continuous-flow LVAD unloading induced in a subset of patients, both ischemic and nonischemic, early improvement in myocardial structure and systolic and diastolic function that was largely completed within 6 months, with no evidence of subsequent regression.

Drakos, Stavros G.; Wever-Pinzon, Omar; Selzman, Craig H.; Gilbert, Edward M.; Alharethi, Rami; Reid, Bruce B.; Saidi, Abdulfattah; Diakos, Nikolaos A.; Stoker, Sandi; Davis, Erin S.; Movsesian, Matthew; Li, Dean Y.; Stehlik, Josef; Kfoury, Abdallah G.

2013-01-01

215

Evaluation of Heterogeneity in the Association between Congenital Heart Defects and Variants of Folate Metabolism Genes: Conotruncal and Left-Sided Cardiac Defects  

PubMed Central

PURPOSE Genetic variation in the folate metabolic pathway may influence the risk of congenital heart defects. This study was undertaken to assess the associations between the inherited and maternal genotypes for variants in folate-related genes and the risk of a composite heart phenotype that included two component phenotypes: conotruncal heart defects (CTDs) and left-sided cardiac lesions (LSLs). METHODS Nine folate-related gene variants were evaluated using data from 692 case-parent triads (CTD, n=419; LSL, n=273). Log-linear analyses were used to test for heterogeneity of the genotype-phenotype association across the two component phenotypes (i.e. CTD and LSLS) and, when there was no evidence of heterogeneity, to assess the associations of the maternal and inherited genotypes with the composite phenotype. RESULTS There was little evidence of heterogeneity of the genotype-phenotype association across the two component phenotypes or of an association between the genotypes and the composite phenotype. There was evidence of heterogeneity in the association of the maternal MTR A2756G genotype (p = 0.01) with CTDs and LSLs. However, further analyses suggested that the observed associations with the maternal MTR A2756G genotype might be confounded by parental imprinting effects. CONCLUSIONS Our analyses of these data provide little evidence that the folate-related gene variants evaluated in this study influence the risk of this composite congenital heart defect phenotype. However, larger and more comprehensive studies that evaluate parent-of-origin effects, as well as additional folate-related genes, are required to more fully explore the relation between folate and congenital heart defects.

Long, Jin; Lupo, Philip J.; Goldmuntz, Elizabeth; Mitchell, Laura E.

2011-01-01

216

c-kit+ Cardiac Stem Cells Alleviate Post-Myocardial Infarction Left Ventricular Dysfunction Despite Poor Engraftment and Negligible Retention in the Recipient Heart  

PubMed Central

Although transplantation of c-kit+ cardiac stem cells (CSCs) has been shown to alleviate left ventricular (LV) dysfunction induced by myocardial infarction (MI), the number of exogenous CSCs remaining in the recipient heart following transplantation and their mechanism of action remain unclear. We have previously developed a highly sensitive and accurate method to quantify the absolute number of male murine CSCs in female recipient organs after transplantation. In the present study, we used this method to monitor the number of donor CSCs in the recipient heart after intracoronary infusion. Female mice underwent a 60-min coronary occlusion followed by reperfusion; 2 days later, 100,000 c-kit+/lin- syngeneic male mouse CSCs were infused intracoronarily. Only 12.7% of the male CSCs present in the heart immediately (5 min) after infusion were still present in the heart at 24 h, and their number declined rapidly thereafter. By 35 days after infusion, only ?1,000 male CSCs were found in the heart. Significant numbers of male CSCs were found in the lungs and kidneys, but only in the first 24 h. The number of CSCs in the lungs increased between 5 min and 24 h after infusion, indicating recirculation of CSCs initially retained in other organs. Despite the low retention and rapid disappearance of CSCs from the recipient heart, intracoronary delivery of CSCs significantly improved LV function at 35 days (Millar catheter). These results suggest that direct differentiation of CSCs alone cannot account for the beneficial effects of CSCs on LV function; therefore, paracrine effects must be the major mechanism. The demonstration that functional improvement is dissociated from survival of transplanted cells has major implications for our understanding of cell therapy. In addition, this new quantitative method of stem cell measurement will be useful in testing approaches of enhancing CSC engraftment and survival after transplantation.

Li, Qian-Hong; Cao, Pengxiao; Al-Maqtari, Tareq; Vajravelu, Bathri N.; Du, Junjie; Book, Michael J.; Zhu, Xiaoping; Nong, Yibing; Bhatnagar, Aruni; Bolli, Roberto

2014-01-01

217

Interaction between respiration and right versus left ventricular volumes at rest and during exercise: a real-time cardiac magnetic resonance study.  

PubMed

Breathing-induced changes in intrathoracic pressures influence left ventricular (LV) and right ventricular (RV) volumes, the exact nature and extent of which have not previously been evaluated in humans. We sought to examine this "respiratory pump" using novel real-time cardiac magnetic resonance (CMR) imaging. Eight healthy subjects underwent serial multislice real-time CMR during normal breathing, breath holding, and the Valsalva maneuver. Subsequently, a separate cohort of nine subjects underwent real-time CMR at rest and during incremental exercise. LV and RV end-diastolic volume (EDV) and end-systolic volume (ESV) and diastolic and systolic eccentricity indexes were determined at peak inspiration and expiration. During normal breathing, inspiration resulted in an increase in RV volumes [RVEDV: +18 ± 8%, RVESV: +14 ± 12%, and RV stroke volume (SV): +21 ± 10%, P < 0.01] and an opposing decrease in LV volumes (P < 0.0001 for interaction). During end-inspiratory breath holding, RV SV decreased by 9 ± 10% (P = 0.046), whereas LV SV did not change. During the Valsalva maneuver, volumes decreased in both ventricles (RVEDV: -29 ± 11%, RVESV: -16 ± 14%, RV SV: -36 ± 14%, LVEDV: -22 ± 17%, and LV SV: -25 ± 17%, P < 0.01). The reciprocal effect of respiration on LV and RV volumes was maintained throughout exercise. The diastolic and systolic eccentricity indexes were greater during inspiration than during expiration, both at rest and during exercise (P < 0.0001 for both). In conclusion, ventricular volumes oscillate with respiratory phase such that RV and LV volumes are maximal at peak inspiration and expiration, respectively. Thus, interpretation of RV versus LV volumes requires careful definition of the exact respiratory time point for proper interpretation, both at rest and during exercise. PMID:24464754

Claessen, Guido; Claus, Piet; Delcroix, Marion; Bogaert, Jan; La Gerche, Andre; Heidbuchel, Hein

2014-03-01

218

Diastolic function after cardiac and heart-lung transplantation.  

PubMed Central

The mechanical efficiency of left ventricular contraction and relaxation, the asynchrony of the onset of left ventricular relaxation, the time constant of left ventricular isovolumic pressure decay, and left ventricular chamber and myocardial stiffness were analysed in 32 patients after cardiac (24) and heart-lung transplantation (8). After cardiac transplantation left ventricular myocardial stiffness was increased and a mild degree of incoordinate contraction and relaxation was seen. In contrast, after heart-lung transplantation diastolic function was almost normal. Impairment of passive diastolic properties was significantly related to the ischaemic time of the donor heart and the donor's age. The index of left ventricular asynchrony was related to the ischaemic time and the recipient's age. The interval between transplantation and study did not influence the number of rejection episodes. This study confirms the presence of diastolic dysfunction after cardiac transplantation. Impairment of diastolic function seems to be related to the ischaemic time of the donor heart and to a mismatch between the size of the donor heart and the recipient's needs.

Hausdorf, G; Banner, N R; Mitchell, A; Khaghani, A; Martin, M; Yacoub, M

1989-01-01

219

Geometry-Independent Inclusion of Basal Myocardium Yields Improved Cardiac Magnetic Resonance Agreement with Echocardiography and Necropsy Quantified Left Ventricular Mass  

PubMed Central

Objectives LV mass (LVM) is widely used to guide clinical decision-making. Cardiac magnetic resonance (CMR) quantifies LVM by planimetry of contiguous short axis images, an approach dependent on reader-selection of images to be contoured. Established methods have applied different binary cutoffs using circumferential extent of LV myocardium to define the basal LV, omitting images containing lesser fractions of LV myocardium. This study tested impact of basal slice variability on LVM quantification. Methods CMR was performed in patients and laboratory animals. LVM was quantified with full inclusion of LV myocardium, and by established methods that use different cutoffs to define the LV basal-most slice: (1) 50% circumferential myocardium at end-diastole alone (ED50), (2) 50% circumferential myocardium throughout both end-diastole and end-systole (EDS50). Results 150 patients and 10 lab animals were studied. Among patients, fully inclusive LVM (172.6±42.3gm) was higher vs. ED50(167.2±41.8gm) and EDS50(150.6±41.1gm; both p<0.001). Methodological differences yielded discrepancies regarding proportion of patients meeting established criteria for LV hypertrophy and chamber dilation (p<0.05). Fully inclusive LVM yielded smaller differences with echocardiography (?=11.0±28.8gm) than did ED50 (?=16.4±29.1gm) and EDS50 (?=33.2±28.7gm, both p<0.001). Among lab animals, ex-vivo LV weight (69.8±13.2gm) was similar to LVM calculated using fully inclusive (70.1±13.5gm, p=0.67) and ED50 (69.4±13.9gm, p=0.70) methods, whereas EDS50 differed significantly (67.9±14.9gm, p=0.04). Conclusions Established CMR methods that discordantly define the basal-most LV produce significant differences in calculated LVM. Fully inclusive quantification, rather than binary cutoffs that omit basal LV myocardium, yields smallest CMR discrepancy with echocardiography-measured LVM and non-significant differences with necropsy-measured LV weight.

SIMPRINI, Lauren A.; GOYAL, Parag; CODELLA, Noel; FIENO, David S.; AFROZ, Anika; MULLALLY, Jamie; COOPER, Mitchell; WANG, Yi; FINN, John Paul; DEVEREUX, Richard B.; WEINSAFT, Jonathan W.

2014-01-01

220

-selectin and SDF-1 enhance the migration of mouse and human cardiac mesoangioblasts  

PubMed Central

Efficient delivery of stem cells to heart regions is still a major problem for cell therapy. Here, we report experiments aimed to improve migration of mouse and human cardiac mesoangioblasts to the damaged heart. Cardiac mesoangioblasts were induced to transmigrate through the endothelium by factors released by cardiomyocytes or cytokines, among which stromal-derived factor 1 (SDF-1) was the most potent. Cardiac mesoangioblasts were also delivered into the left ventricular (LV) chamber of mice after coronary artery ligation (CAL), and their in vivo homing to the damaged heart was found to be quite modest. Pretreatment of cardiac mesoangioblasts with SDF-1 or transient expression of -selectin induced a two- to three-fold increase in their transmigration and homing to the damaged heart. Therefore, combined pretreatment with SDF-1 and -selectin generated modified cardiac mesoangioblasts, 50% of which, after injection into the LV chamber of mice early after CAL, home directly to the damaged free wall of the heart. Finally, modified mouse cardiac mesoangioblasts, injected into the LV chamber regenerate a larger surface of the ventricle in long-term experiments in comparison with their control counterparts. This study defines the requirements for efficient homing of cardiac mesoangioblasts to the damaged heart and offers a new potent tool to optimize efficiency of future cell therapy protocols for cardiovascular diseases.

Bernal, A; San Martin, N; Fernandez, M; Covarello, D; Molla, F; Soldo, A; Latini, R; Cossu, G; Galvez, B G

2012-01-01

221

Coronary fistula between the left anterior descending coronary artery and the pulmonary artery: Two case reports  

PubMed Central

Coronary artery fistulae are rare congenital or acquired connections between the coronary vessels and the cardiac chambers or other vascular structures. We present two consecutive cases of coronary fistulae between the proximal left anterior descending artery (LAD) and the main pulmonary artery. Both cases where admitted with history of acute coronary syndromes and had multivessel coronary disease along with coronary pulmonary fistulae. The two cases were managed by coronary artery bypass grafting (CABG) and repair of the fistulae.

Ibrahim, Mohamed F.; Sayed, Sameh; Elasfar, Abdelfatah; Sallam, Ayman; Fadl, Mazin; Al Baradai, Abdulaziz

2012-01-01

222

Right coronary artery to left ventricle fistula—Effective diagnosis with 64MDCT  

Microsoft Academic Search

Coronary artery fistula is a rare congenital anomaly in which a communication is present between a cardiac chamber or another\\u000a vascular structure. In this paper, we describe a 52-year-old asymptomatic male patient with a right coronary artery to left\\u000a ventricle fistula. We demonstrate the effectiveness of 64-MDCT (Multi-detector row computed tomography) in demonstrating the\\u000a precise anatomy of this fistula in

Dilek Oncel; Guray Oncel

2007-01-01

223

Non-invasive measurement of cardiac output by whole-body bio-impedance during dobutamine stress echocardiography: Clinical implications in patients with left ventricular dysfunction and ischaemia  

Microsoft Academic Search

Objectives: To compare non-invasive determination of cardiac index (CI) by whole body electrical bioimpedance using the NICaS apparatus and Doppler echocardiography, and the role of cardiac power index (Cpi) and total peripheral resistance index (TPRi) calculation during dobutamine stress echocardiography (DSE). Subjects and methods: We enrolled 60 consecutive patients undergoing DSE. Patients were prospectively divided into 3 groups: Group 1

Marina Leitman; Edgar Sucher; Edo Kaluski; Ruth Wolf; Eli Peleg; Yaron Moshkovitz; Olga Milo-Cotter; Zvi Vered; Gad Cotter

224

Congenital biventricular cardiac diverticula in a dog.  

PubMed

Multiple diverticula of the right and left cardiac ventricular walls were incidental findings at necropsy in a juvenile, male, mixed-breed dog with no clinical history of heart disease. Each saccular diverticulum had a narrow communication into the corresponding ventricular chamber. Histologically, the diverticular walls consisted mainly of collagen without elastin fibers and atrophic cardiomyocytes. No inflammation or other lesions were associated with the diverticula or the rest of the myocardium. Based on the history and pathologic findings, a diagnosis of congenital biventricular fibrous diverticula was made. PMID:20634411

Herráez, P; Rodríguez, F; Aguirre-Sanceledonio, M; Edwards, J F; Suárez-Bonnet, A; Espinosa de Los Monteros, A

2011-03-01

225

Six-Year Experience Routinely Utilizing Moderate Deep Inspiration Breath-hold (mDIBH) for the Reduction of Cardiac Dose in Left-Sided Breast Irradiation for Patients with Early Stage or Locally Advanced Breast Cancer  

PubMed Central

Purpose/Objectives Moderate Deep Inspiration Breath-hold (mDIBH), utilizing an Active breathing Control (ABC) device has been used in our clinic since 2002 to reduce cardiac dose for patients receiving left-sided breast irradiation. We report our routine use of the mDIBH technique in clinically localized breast cancer, treated to the intact breast, reconstructed breast, or chest wall. Materials/Methods Ninety-nine patients with left sided breast cancer were evaluated for ABC treatment, of which, 87 patients were treated with mDIBH. Plans for both the free-breathing (FB) and mDIBH CT scans were evaluated. Dose volume histograms (DVHs) were analyzed for the heart and ipsilateral lung, comparing results for mDIBH vs FB plans. Results Eighty-seven patients are included for analysis. Of those, 66% received adjuvant chemotherapy with cardiotoxic agents. The mean dose to the whole breast was 47.6 Gy. There was a statistically significant decrease in all DVH parameters evaluated, favoring the delivery of mDIBH over FB plans. mDIBH plans significantly reduced cardiac mean dose (4.23 Gy vs. 2.54 Gy; p<0.001), a relative reduction of 40%. As well, there were significant reductions in all other heart parameters evaluated (i.e volume of heart treated, V30, V25, V20, V15, V10, and V5). mDIBH also significantly reduced lung dose, including a reduction of the left lung mean dose (9.08 Gy vs. 7.86 Gy; p<0.001), a relative reduction of 13%, as well as significant reduction of all lung DVH parameters evaluated. Conclusions To date, this series represents the largest experience utilizing mDIBH to reduce cardiac irradiation during left-sided breast cancer treatment. Statistically significant reductions in all heart and lung DVH parameters were achieved with mDIBH over FB plans. mDIBH, for the treatment of left sided breast cancer, is a proven technique for reducing cardiac dose that may lead to reduced cardiotoxicity and can be routinely integrated into the clinic.

Swanson, T.; Grills, I.; Ye, H.; Entwistle, A.; Teahan, M.; Letts, N.; Yan, D.; Duquette, J.; Vicini, F.

2012-01-01

226

Echocardiographic detection of left atrial mobile calcium debris of trido valve surgery: a case report  

PubMed Central

Calcification of the cardiac chambers is among the challenges associated with reoperative cardiac surgeries by increasing the risk of systemic embolization. We experienced a case of an unexpected detected mass by intraoperative transesophageal echocardiography during weaning from cardiopulmonary bypass in a patient undergoing trido mitral and tricuspid valve replacement surgery. The surgically removed mass was identified as calcified tissue. This case shows the importance of careful echocardiographic evaluation of the left heart in patients undergoing repeat valve surgery given their greater potential for embolic sources.

Song, Young; Shim, Jae-Kwang; Sun, Jong-Min; Lee, Bora

2014-01-01

227

Vector Selection of a Quadripolar Left Ventricular Pacing Lead Affects Acute Hemodynamic Response to Cardiac Resynchronization Therapy: A Randomized Cross-Over Trial  

PubMed Central

Background A suboptimal left ventricular (LV) pacing site may account for non-responsiveness of patients to cardiac resynchronization therapy (CRT). The vector selection of a novel quadripolar LV pacing lead, which was mainly developed to overcome technical issues with stimulation thresholds and phrenic nerve capture, may affect hemodynamic response, and was therefore assessed in this study. (German Clinical Trials Register DRKS00000573). Methods and Results Hemodynamic effects of a total of 145 LVPCs (9.1 per patient) of CRT devices with a quadripolar LV lead (Quartet™, St. Jude Medical) were assessed in 16/20 consecutive patients by invasive measurement of LV+dP/dtmax at an invasively optimized AV-interval in random order. Optimal (worst) LVPCs per patient were identified as those with maximal (minimal) %change in LV+dP/dtmax (%?LV+dP/dtmax) as compared to a preceding baseline. LV+dP/dtmax significantly increased in all 145 LVPCs (p<0.0001 compared to baseline) with significant intraindividual differences between LVPCs (p<0.0001). Overall, CRT acutely augmented %?LV+dP/dtmax by 31.3% (95% CI 24%–39%) in the optimal, by 21.3% (95% CI: 15%–27%) in the worst and by 28.2% (95% CI: 21%–36%) in a default distal LVPC. This resulted in an absolute additional acute increase in %?LV+dP/dtmax of 10.0% (95% CI: 7%–13%) of the optimal when compared to the worst (p<0.0001), and of 3.1% (95% CI: 1%–5%) of the optimal when compared to the default distal LVPC (p<0.001). Optimal LVPCs were not programmable with a standard bipolar lead in 44% (7/16) of patients. Conclusion The pacing configuration of a quadripolar LV lead determinates acute hemodynamic response. Pacing in the individually optimized configuration gives rise to an additional absolute 10% increase in %?LV+dP/dtmax when comparing optimal and worst vectors.

Asbach, Stefan; Hartmann, Maximilian; Wengenmayer, Tobias; Graf, Erika; Bode, Christoph; Biermann, Juergen

2013-01-01

228

Characterization of respiratory and cardiac motion from electro-anatomical mapping data for improved fusion of MRI to left ventricular electrograms.  

PubMed

Accurate fusion of late gadolinium enhancement magnetic resonance imaging (MRI) and electro-anatomical voltage mapping (EAM) is required to evaluate the potential of MRI to identify the substrate of ventricular tachycardia. However, both datasets are not acquired at the same cardiac phase and EAM data is corrupted with respiratory motion limiting the accuracy of current rigid fusion techniques. Knowledge of cardiac and respiratory motion during EAM is thus required to enhance the fusion process. In this study, we propose a novel approach to characterize both cardiac and respiratory motion from EAM data using the temporal evolution of the 3D catheter location recorded from clinical EAM systems. Cardiac and respiratory motion components are extracted from the recorded catheter location using multi-band filters. Filters are calibrated for each EAM point using estimates of heart rate and respiratory rate. The method was first evaluated in numerical simulations using 3D models of cardiac and respiratory motions of the heart generated from real time MRI data acquired in 5 healthy subjects. An accuracy of 0.6-0.7 mm was found for both cardiac and respiratory motion estimates in numerical simulations. Cardiac and respiratory motions were then characterized in 27 patients who underwent LV mapping for treatment of ventricular tachycardia. Mean maximum amplitude of cardiac and respiratory motion was 10.2±2.7 mm (min?=?5.5, max?=?16.9) and 8.8±2.3 mm (min?=?4.3, max?=?14.8), respectively. 3D Cardiac and respiratory motions could be estimated from the recorded catheter location and the method does not rely on additional imaging modality such as X-ray fluoroscopy and can be used in conventional electrophysiology laboratory setting. PMID:24250815

Roujol, Sébastien; Anter, Elad; Josephson, Mark E; Nezafat, Reza

2013-01-01

229

[Heart size and left ventricular function in coronary artery disease: I. Heart size, exercise tolerance, cardiac output and filling pressures (author's transl)].  

PubMed

The possible relationship between the cardiac volume, as determined radiologically in the supine position in 119 patients with angiographically proven coronary artery disease, and the results of ergometry and balloon catheterization was investigated. There was no relationship between the heart size on the one side and the maximum exercise tolerance and the maximum cardiac output on the other, except for the fact, that these parameters tended to decrease with increasing heart size. This was especially true in patients with angina. The maximum cardiac output of patients with angina was always below the value of patients without angina but comparable heart size. Reduced cardiac output under exercise (exertional cardiac insufficiency) was present in 50% of patients with enlarged hearts but already in 22% of patients with heart volumes in the lower range of normal. The diastolic pulmonary artery pressure, determined under exercise, was the only parameter with a significant relationship to the heart size: The larger the heart size, the higher the diastolic pulmonary artery pressure. On the other hand: the diastolic pulmonary artery pressure at rest was abnormal with significant frequency only, when the heart was enlarged. Our data suggest, that the hemodynamics are determined by 2 factors: Myocardial scarring secondary to infarction and coronary insufficiency (ischemia). Of these two factors only the former influences cardiac size. Therefore, determination of the heart volume helps evaluating the respective role of these two factors in individual cases. PMID:927289

Meuret, G; Jaedicke, W; Barmeyer, J; Wink, K; König, K; Reindell, H

1977-11-01

230

Registration-based segmentation of murine 4D cardiac micro-CT data using symmetric normalization  

PubMed Central

Micro-CT can play an important role in preclinical studies of cardiovascular disease because of its high spatial and temporal resolution. Quantitative analysis of 4D cardiac images requires segmentation of the cardiac chambers at each time point, an extremely time consuming process if done manually. To improve throughput this study proposes a pipeline for registration-based segmentation and functional analysis of 4D cardiac micro-CT data in the mouse. Following optimization and validation using simulations, the pipeline was applied to in vivo cardiac micro-CT data corresponding to 10 cardiac phases acquired in C57BL/6 mice (n = 5). After edge-preserving smoothing with a novel adaptation of 4D bilateral filtration, one phase within each cardiac sequence was manually segmented. Deformable registration was used to propagate these labels to all other cardiac phases for segmentation. The volumes of each cardiac chamber were calculated and used to derive stroke volume, ejection fraction, cardiac output, and cardiac index. Dice coefficients and volume accuracies were used to compare manual segmentations of two additional phases with their corresponding propagated labels. Both measures were, on average, >0.90 for the left ventricle and >0.80 for the myocardium, the right ventricle, and the right atrium, consistent with trends in inter- and intra-segmenter variability. Segmentation of the left atrium was less reliable. On average, the functional metrics of interest were underestimated by 6.76% or more due to systematic label propagation errors around atrioventricular valves; however, execution of the pipeline was 80% faster than performing analogous manual segmentation of each phase.

Clark, Darin; Badea, Alexandra; Liu, Yilin; Johnson, G. Allan; Badea, Cristian T.

2013-01-01

231

Multi-Physics MRI-Based Two-Layer Fluid-Structure Interaction Anisotropic Models of Human Right and Left Ventricles with Different Patch Materials: Cardiac Function Assessment and Mechanical Stress Analysis  

PubMed Central

Multi-physics right and left ventricle (RV/LV) fluid-structure interaction (FSI) models were introduced to perform mechanical stress analysis and evaluate the effect of patch materials on RV function. The FSI models included three different patch materials (Dacron scaffold, treated pericardium, and contracting myocardium), two-layer construction, fiber orientation, and active anisotropic material properties. The models were constructed based on cardiac magnetic resonance (CMR) images acquired from a patient with severe RV dilatation and solved by ADINA. Our results indicate that the patch model with contracting myocardium leads to decreased stress level in the patch area, improved RV function and patch area contractility.

Tang, Dalin; Yang, Chun; Geva, Tal; Gaudette, Glenn; del Nido, Pedro J.

2011-01-01

232

Prediction of 6 months left ventricular dilatation after myocardial infarction in relation to cardiac morbidity and mortality. Application of a new dilatation model to GISSI-3 data  

Microsoft Academic Search

Aims To predict the long-term left ventricular volume index early after myocardial infarction and to investigate the relationship between long-term left ventricular dilatation risk and clinical outcome. Methods and Results By applying a previously developed dilatation model, we predicted the 6-month left ventricular volume index early after myocardial infarction (median 9 days) in 13 679 GISSI-3 patients, to identify patients

P. J. de Kam; G. L. Nicolosi; A. A. Voors; M. P. van den Berg; J. Brouwer; D. J. van Veldhuisen; S. Barlera; A. P. Maggioni; P. Giannuzzi; P. L. Temporelli; R. Latini; W. H. van Gilst

2002-01-01

233

Normobaric hypoxia impairs human cardiac energetics.  

PubMed

Hypoxia causes left ventricular dysfunction in the human heart, but the biochemical mechanism is poorly understood. Here, we tested whether short-term normobaric hypoxia leads to changes in cardiac energetics and early cardiac dysfunction. Healthy male volunteers (n=12, age 24 ± 2 yr) were exposed to normobaric hypoxia in a purpose-built hypoxic chamber. The partial pressure of oxygen during end-tidal expiration (P(ET)o?) was kept between 50 and 60 mmHg, and peripheral oxygen saturation (Sao?) was kept above 80%. Cardiac morphology and function were assessed using magnetic resonance imaging and echocardiography, both before and after 20 h of hypoxic exposure, and high-energy phosphate metabolism [measured as the phosphocreatine (PCr)/ATP ratio] was measured using ³¹P magnetic resonance spectroscopy. During hypoxia, P(ET)o? and Sao? averaged 55 ± 1 mmHg and 83.6 ± 0.4%, respectively. Hypoxia caused a 15% reduction in cardiac PCr/ATP (from 2.0 ± 0.1 to 1.7 ± 0.1, P<0.01) and reduced diastolic function (measured as E/E', rising from 6.1 ± 0.4 to 7.5 ± 0.7, P<0.01). Normobaric hypoxia causes a rapid decrease in high-energy phosphate metabolism in the human cardiac left ventricle, which may lead to a decline in diastolic function. These findings are important in understanding the response of normal individuals to environmental hypoxia, and to situations in which disease reduces cardiac oxygen delivery. PMID:21646398

Holloway, Cameron; Cochlin, Lowri; Codreanu, Ion; Bloch, Edward; Fatemian, Marzieh; Szmigielski, Cezary; Atherton, Helen; Heather, Lisa; Francis, Jane; Neubauer, Stefan; Robbins, Peter; Montgomery, Hugh; Clarke, Kieran

2011-09-01

234

Congenital left ventricular diverticulum diagnosed by echocardiography.  

PubMed

Congenital left ventricular diverticulum is a rare cardiac malformation. The incidence of left ventricular diverticulum is reported to be 0.05% of all congenital heart malformations. This case series comprised three infants with the diagnosis of congenital left ventricular diverticulum determined by echocardiography. In addition, two of the three babies also were detected to have other cardiac disease. Echocardiography is a useful tool for diagnosing congenital left ventricular diverticulum. PMID:22290590

Yang, Hui; Zhu, Qi; Chen, Jiao; Guo, Nan

2012-04-01

235

Repeated Aborted Sudden Cardiac Death with Long QT Syndrome in a Patient with Anomalous Origin of the Right Coronary Artery from the Left Coronary Cusp.  

PubMed

A 15-year-old female with a prior history of aborted cardiac death and surgical correction of anomalous origin of the right coronary artery (RCA) presented with polymorphic ventricular tachycardia. Her electrocardiogram after defibrillation was suggestive of congenital long QT syndrome (LQTS). The patient was treated with a ?-blocker and remained free from ventricular arrhythmia during the follow-up of more than 6 months. Here, we present the case of a young female with repeated aborted cardiac death accompanied by anomalous origin of the RCA and congenital LQTS for the first time. PMID:24385995

Park, Yae Min; Kim, Su Ji; Park, Chul-Hyun; Kang, Woong Chol; Shin, Mi-Seung; Koh, Kwang Kon; Choi, In Suck

2013-12-01

236

Repeated Aborted Sudden Cardiac Death with Long QT Syndrome in a Patient with Anomalous Origin of the Right Coronary Artery from the Left Coronary Cusp  

PubMed Central

A 15-year-old female with a prior history of aborted cardiac death and surgical correction of anomalous origin of the right coronary artery (RCA) presented with polymorphic ventricular tachycardia. Her electrocardiogram after defibrillation was suggestive of congenital long QT syndrome (LQTS). The patient was treated with a ?-blocker and remained free from ventricular arrhythmia during the follow-up of more than 6 months. Here, we present the case of a young female with repeated aborted cardiac death accompanied by anomalous origin of the RCA and congenital LQTS for the first time.

Park, Yae Min; Kim, Su Ji; Park, Chul-Hyun; Kang, Woong Chol; Shin, Mi-Seung; Koh, Kwang Kon

2013-01-01

237

Left ventricular hemangioma.  

PubMed

A young Saudi woman presented with symptoms of palpitation, near syncope, anxiety, and fatigue. Transthoracic echocardiography showed a left ventricular mass. Under cardiopulmonary bypass, brief cardioplegic arrest, and the aid of a thoracoscope, the mass was resected. Histologic examination showed a rare benign cardiac tumor: mixed cavernous-capillary hemangioma. PMID:24585648

Oueida, Farouk M; Lui, Raphael C; Al-Refae, Mustafa A; Al-Omran, Hamed M

2014-01-01

238

Moderate cardiac-selective overexpression of angiotensin type 2 receptor protects cardiac functions from ischemic injury  

PubMed Central

Aim We hypothesize that moderate cardiac-selective overexpression of the angiotensin type 2 receptor (AT2R) would protect the myocardium from ischemic injury after a myocardial infarction (MI) induced by coronary artery ligation. METHODS AND RESULTS For the in vitro studies, Ad-G-AT2R-EGFP was used to overexpress AT2R in rat neonatal cardiac myocytes (RNCM). Expression of AT2R, measured by real-time PCR and immunostaining demonstrated efficient transduction of AT2R in a dose-dependent pattern. AT2R constitutively induced apoptosis in RNCM in dose-dependent patterns. For the in vivo studies, 4×1010 vector genome (vg) of rAAV9-CBA-AT2R was injected into the left ventricle chamber of the heart in 5-day-old Sprague-Dawley rats. At six weeks of age, hearts were harvested and expression of AT2R determined by real time PCR and western blotting. Expression was increased one fold over controls and no apoptosis was detected. Two subsequent in vivo studies were performed. In a prevention study 4×1010 vg of rAAV9-CBA-AT2R was injected into the left ventricle chamber of the heart in 5-day-old Sprague-Dawley rats and MI was induced at six week of age. For a post treatment study 4×1010 vg of rAAV9-CBA-AT2R was administrated to the peri-infarcted myocardium area immediately after MI in six week old animals. For both in vivo studies, cardiac functions were assessed using echocardiography and hemodynamic measurements four weeks after coronary artery ligation. In the in vivo studies the MI rats showed significant decreases in fractional shortening and dP/dt with an increased left ventricular end diastolic pressure and a ventricular hypertrophy. For the prevention study, the moderate cardiac-selective overexpression of AT2R attenuated the above MI-induced impairments and also caused a decrease in ventricular wall thinning. In the post treatment study, the overexpression of AT2R partially reversed the MIinduced cardiac dysfunction. MI also induced the up-regulation of AT1R, ACE, and Collagen I mRNA expression, all of which were attenuated by the overexpression of AT2R. CONCLUSION Moderate cardiac-selective overexpression of AT2R protects heart function from ischemic injury, which may be mediated, at least in part, through modulation of components of the cardiac RAS and collagen levels in the myocardium.

Qi, Yanfei; Li, Hongwei; Shenoy, Vinayak; Li, Qiuhong; Wong, Fong; Zhang, Ling; Raizada, Mohan K; Sumners, Colin; Katovich, Michael J

2013-01-01

239

Color-coded measures of myocardial velocity throughout the cardiac cycle by tissue Doppler imaging to quantify regional left ventricular function  

Microsoft Academic Search

TDI is a new echocardiographic technique that calculates and displays color-coded myocardial velocity on-line. To determine the feasibility of endocardial velocity throughout the cardiac cycle as a means to quantify regional function, 20 normal subjects aged 30 ± 5 years and 12 patients with heart disease aged 62 ± 17 years were studied with a prototype TDI system. TDI M-mode

John Gorcsan; Vijay K. Gulati; William A. Mandarino; William E. Katz

1996-01-01

240

The worsening of left ventricular hypertrophy is the strongest predictor of sudden cardiac death in haemodialysis patients: a 10 year survey  

Microsoft Academic Search

Background. Although the incidence of sudden cardiac death (SCD) is high among haemodialysis (HD) patients, there are few papers available on this topic. The aim of this study on a single-centre HD popula- tion observed over a 10 year period was to identify patient- and HD-related specific factors that might be associated with a higher risk of SCD. Methods. The

Ernesto Paoletti; Claudia Specchia; Diego Bellino; Beatrice Damasio; Paolo Cassottana; Giuseppe Cannella

2004-01-01

241

Anomalous origin of the left coronary artery from the pulmonary trunk and its relationship with the morphology of the cardiac semilunar valves in Syrian hamsters  

Microsoft Academic Search

The conditions of the aortic and pulmonary valves and the arrangement in the origin of the coronary arteries were studied in 247 Syrian hamsters belonging to a single family subjected to high endogamous pressure. Most specimens (n=216) were examined using a stereomicroscope. The remaining 31 were studied histologically. In 110 specimens both cardiac semilunar valves were normal. The aortic valve

M. Cardo; B. Fernández; A. C. Durán; J. M. Arqué; D. Franco; V. Sans-Coma

1994-01-01

242

Cardiac anatomy revisited  

PubMed Central

In tomorrow's world of clinical medicine, students will increasingly be confronted by anatomic displays reconstructed from tomographically derived images. These images all display the structure of the various organs in anatomical orientation, this being determined in time-honoured fashion by describing the individual in the ‘anatomical position’, standing upright and facing the observer. It follows from this approach that all adjectives used to describe the organs should be related to the three orthogonal planes of the body. Unfortunately, at present this convention is not followed for the heart, even though most students are taught that the so-called ‘right chambers’ are, in reality, in front of their ‘left’ counterparts. Rigorous analysis of the tomographic images already available, along with comparison with dissected hearts displayed in attitudinally correct orientation, calls into question this continuing tendency to describe the heart in terms of its own orthogonal axes, but with the organ positioned on its apex, so that the chambers can artefactually be visualized with the right atrium and right ventricle in right-sided position. Although adequate for describing functional aspects, such as ‘right-to-left’ shunting across intracardiac communications, this convention falls short when used to describe the position of the artery that supplies the diaphragmatic surface of the heart. Currently known as the ‘posterior descending artery’, in reality it is positioned inferiorly, and its blockage produces inferior myocardial infarction. In this review, we extend the concept of describing cardiac structure in attitudinally correct orientation, showing also how access to tomographic images clarifies many aspects of cardiac structure previously considered mysterious and arcane. We use images prepared using new techniques such as magnetic resonance imaging and computerized tomography, and compare them with dissection of the heart made in time-honoured fashion, along with cartoons to illustrate contentious topics. We argue that there is much to gain by describing the components of the heart as seen in the anatomical position, along with all other organs and structures in the body. We recognize, nonetheless, that such changes will take many years to be put into practice, if at all.

Anderson, Robert H; Razavi, Reza; Taylor, Andrew M

2004-01-01

243

Electrostatic Levitator Vacuum Chamber  

NASA Technical Reports Server (NTRS)

Optical ports ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (beam passes through the window at left), positioning lasers (one port is at center), and lamps to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

1998-01-01

244

Cardiac function adaptations in hibernating grizzly bears (Ursus arctos horribilis).  

PubMed

Research on the cardiovascular physiology of hibernating mammals may provide insight into evolutionary adaptations; however, anesthesia used to handle wild animals may affect the cardiovascular parameters of interest. To overcome these potential biases, we investigated the functional cardiac phenotype of the hibernating grizzly bear (Ursus arctos horribilis) during the active, transitional and hibernating phases over a 4 year period in conscious rather than anesthetized bears. The bears were captive born and serially studied from the age of 5 months to 4 years. Heart rate was significantly different from active (82.6 +/- 7.7 beats/min) to hibernating states (17.8 +/- 2.8 beats/min). There was no difference from the active to the hibernating state in diastolic and stroke volume parameters or in left atrial area. Left ventricular volume:mass was significantly increased during hibernation indicating decreased ventricular mass. Ejection fraction of the left ventricle was not different between active and hibernating states. In contrast, total left atrial emptying fraction was significantly reduced during hibernation (17.8 +/- 2.8%) as compared to the active state (40.8 +/- 1.9%). Reduced atrial chamber function was also supported by reduced atrial contraction blood flow velocities and atrial contraction ejection fraction during hibernation; 7.1 +/- 2.8% as compared to 20.7 +/- 3% during the active state. Changes in the diastolic cardiac filling cycle, especially atrial chamber contribution to ventricular filling, appear to be the most prominent macroscopic functional change during hibernation. Thus, we propose that these changes in atrial chamber function constitute a major adaptation during hibernation which allows the myocardium to conserve energy, avoid chamber dilation and remain healthy during a period of extremely low heart rates. These findings will aid in rational approaches to identifying underlying molecular mechanisms. PMID:19940994

Nelson, O Lynne; Robbins, Charles T

2010-03-01

245

The cardiac response to exercise in cirrhosis  

PubMed Central

BACKGROUND—Impaired exercise capacity and oxygen consumption are common in cirrhosis.?AIM—To explore the relationship between possible myocardial dysfunction and exercise tolerance in cirrhosis.?METHODS—Cardiac responses to exercise, using radionuclide angiography and graded upright cycle ergometry with oxygen consumption, were assessed before and after exercise in 39 cirrhotics patients and compared with 12 age and sex matched healthy volunteers. Baseline cardiac chamber dimensions and wall thickness, ejection fraction, and diastolic function were measured using two dimensional echocardiography is all subjects.?RESULTS—Baseline diastolic dysfunction with prolonged isovolumic relaxation times (p=0.02), left atrial enlargement, and left ventricular wall thickening were present in all cirrhotics (p=0.02), despite increased mean ejection fraction. With graded exercise, cirrhotics achieved 71 (4)% (p=0.03) (pre-ascitics) and 46 (3)% (p<0.001) (ascitics) of predicted work loads, respectively, without significant increases in ejection fraction. The smaller absolute and percentage increases in cardiac output (p=0.003) in the cirrhotics were associated with significantly reduced oxygen consumption (p=0.003) and anaerobic threshold (p<0.001), and correlated significantly with work and metabolic parameters.?CONCLUSIONS—Impaired exercise capacity in cirrhosis is associated with myocardial thickening and ventricular stiffness leading to decreased diastolic function, inotropic and chronotropic incompetence under conditions of stress, with metabolic consequences. This picture is compatible with the condition now known as cirrhotic cardiomyopathy.???Keywords: cirrhosis; exercise tolerance; myocardial function; oxygen consumption

Wong, F; Girgrah, N; Graba, J; Allidina, Y; Liu, P; Blendis, L

2001-01-01

246

A preliminary study on the evaluation of relationship between left ventricular torsion and cardiac cycle phase by two-dimensional ultrasound speckle tracking imaging  

Microsoft Academic Search

In normal subjects there is a certain corresponding relationship between the peak rotation angle of the apex and the base\\u000a with respect to the phase of the cardiac cycle. We hypothesized that the myocardial contractile force and the delay of conduction\\u000a may affect the correspondence of them. Our study aims to use speckle tracking imaging (STI) technique to analyze the

Xianghong Luo; Tiesheng Cao; Zhaojun Li; Yunyou Duan

2009-01-01

247

Furosemide and Potassium Chloride-induced Alteration in Protein Profile of Left Ventricle and its Associated Risk for Sudden Cardiac Death  

PubMed Central

Background: Potassium ion (K+) plays an essential role in maintaining the electrical potential across the plasma membrane of cells. An abnormal serum K+ level is associated with increased risk of ventricular arrhythmia and sudden cardiac death (SCD) and these patients are generally prescribed with furosemide and potassium chloride (KCl). We explored the association between the use of these drugs and the risk of SCD by analyzing biochemical parameters and proteomic changes. Materials and Methods: The rats were administered with furosemide and KCl and their effect was analyzed by studying cardiac and oxidative markers, electrolyte content and histopathology. Two-dimensional gel electrophoresis (2-DE) and electrospray ionization-mass spectrometry were performed to investigate the LV proteomic changes. Results: Furosemide and KCl treatments showed significant effect on physiological and biochemical parameters, and LV histopathology of experimental rats. Proteomic analysis indicated 17 differentially expressed proteins. Among them, eight protein spots were identified using peptide mass fingerprinting. In furosemide-treated group, four proteins were upregulated and two proteins were downregulated when compared to 2-DE proteomic profile of control. While in KCl-treated rats, seven proteins were found downregulated. Conculsion: The present study revealed the differential expression of proteins by furosemide and KCl treatment. Thus, the results suggest that the use of these drugs leads to proteomic alteration, which involve in cardiac conductivity that might increase the risk of SCD.

Murugan, Ponniah Senthil; Selvam, Govindan Sadasivam

2014-01-01

248

Exposure chamber  

DOEpatents

A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

Moss, Owen R. (Kennewick, WA)

1980-01-01

249

Relation of various degrees of body mass index in patients with systemic hypertension to left ventricular mass, cardiac output, and peripheral resistance (The Hypertension Genetic Epidemiology Network Study)  

Microsoft Academic Search

The impact of different methods of indexation of left ventricular (LV) mass and systemic hemodynamic variables on prevalences and correlates of cardiovascular abnormalities in relation to level of obesity in populations remains unclear. We evaluated 1,672 participants in the Hypertension Genetic Epidemiology Network Study to investigate the relations of overweight and level of obesity to LV mass and prevalences of

Vittorio Palmieri; Giovanni de Simone; Donna K Arnett; Jonathan N Bella; Dalane W Kitzman; Albert Oberman; Paul N Hopkins; Michael A Province; Richard B Devereux

2001-01-01

250

Cross sectional study of contribution of clinical assessment and simple cardiac investigations to diagnosis of left ventricular systolic dysfunction in patients admitted with acute dyspnoea.  

PubMed Central

OBJECTIVE: To assess the comparative contribution of clinical assessment, electrocardiography, and chest radiography to the diagnosis of left ventricular systolic dysfunction in patients admitted to a general medical ward with acute dyspnoea. DESIGN: Prospective cross sectional study. SETTING: Acute medical admissions ward of a teaching hospital. SUBJECTS: 71 randomly selected patients admitted with acute dyspnoea. MAIN OUTCOME MEASURES: Sensitivity and specificity of each investigation and logistic regression analysis of each variable in identifying left ventricular systolic dysfunction. RESULTS: Clinical assessment in this cohort of patients with severe dyspnoea was generally sensitive (sensitivity 81%). Patients were divided into three groups on the basis of clinical assessment. In the first group (37 patients) the diagnosis of systolic dysfunction was clear, in the second (22) it was in doubt, and in the third (12) it was unlikely. The sensitivity of clinical assessment in identifying left ventricular systolic dysfunction was 81% and the specificity was 47%. The specificity of diagnosis was improved by electrocardiography (69%) and chest radiography (92%). Logistic regression analysis showed that isolated pulmonary crepitations were a comparatively poor predictor of left ventricular systolic dysfunction chi 2 = 10.215, P = 0.0014) but that a full clinical examination had reasonable predictive value (chi 2 = 24.82, P < 0.00001). The combination of clinical assessment and chest radiography improved the accuracy of diagnosis (chi 2 = 28.08, P < 0.00001), as did the combination of clinical assessment and electrocardiography (chi 2 = 32.41, P < 0.00001). CONCLUSION: Clinical assessment in patients admitted with acute dyspnoea is comparatively accurate. Patients with abnormal results on chest radiography, electrocardiography, and clinical examination have a high likelihood of having left ventricular systolic dysfunction. Echocardiography contributes little more to the diagnosis in these patients and may be more efficiently directed towards patients in whom the diagnosis is still in doubt after clinical assessment, chest radiography, and electrocardiography.

Gillespie, N. D.; McNeill, G.; Pringle, T.; Ogston, S.; Struthers, A. D.; Pringle, S. D.

1997-01-01

251

Dietary saturated fat and docosahexaenoic acid differentially effect cardiac mitochondrial phospholipid fatty acyl composition and Ca2+ uptake, without altering permeability transition or left ventricular function  

PubMed Central

High saturated fat diets improve cardiac function and survival in rodent models of heart failure, which may be mediated by changes in mitochondrial function. Dietary supplementation with the n3-polyunsaturated fatty acid docosahexaenoic acid (DHA, 22:6n3) is also beneficial in heart failure and can affect mitochondrial function. Saturated fatty acids and DHA likely have opposing effects on mitochondrial phospholipid fatty acyl side chain composition and mitochondrial membrane function, though a direct comparison has not been previously reported. We fed healthy adult rats a standard low-fat diet (11% of energy intake from fat), a low-fat diet supplemented with DHA (2.3% of energy intake) or a high-fat diet comprised of long chain saturated fatty acids (45% fat) for 6 weeks. There were no differences among the three diets in cardiac mass or function, mitochondrial respiration, or Ca2+-induced mitochondrial permeability transition. On the other hand, there were dramatic differences in mitochondrial phospholipid fatty acyl side chains. Dietary supplementation with DHA increased DHA from 7% to ?25% of total phospholipid fatty acids in mitochondrial membranes, and caused a proportional depletion of arachidonic acid (20:4n6). The saturated fat diet increased saturated fat and DHA in mitochondria and decreased linoleate (18:2n6), which corresponded to a decrease in Ca2+ uptake by isolated mitochondria compared to the other diet groups. In conclusion, despite dramatic changes in mitochondrial phospholipid fatty acyl side chain composition by both the DHA and high saturated fat diets, there were no effects on mitochondrial respiration, permeability transition, or cardiac function.

O'Connell, Kelly A; Dabkowski, Erinne R; de Fatima Galvao, Tatiana; Xu, Wenhong; Daneault, Caroline; de Rosiers, Christine; Stanley, William C

2013-01-01

252

Presence of left ventricular contractile reserve, evaluated by means of dobutamine stress-echo test, is able to predict response to cardiac resynchronization therapy  

Microsoft Academic Search

Introduction  We evaluated whether the dobutamine stress-echo test can select responders to cardiac resynchronization therapy (CRT). Up\\u000a to 50% of patients do not respond to CRT. Lack of response may be due to a significant amount of scar or fibrotic tissue at\\u000a myocardial level.\\u000a \\u000a \\u000a \\u000a Methods and Results  We studied 42 CRT patients. After clinical and echocardiographic evaluation, all patients underwent a dobutamine

Bernardino Tuccillo; Raffaele Iengo; Maria Accadia; Salvatore Rumolo; Micheleangelo Canciello; Giovanni Carreras; Raimondo Calvanese; Eduardo Celentano; Mario Davinelli; Sergio Valsecchi; Luigi Ascione

2008-01-01

253

Cardiac stem cells delivered intravascularly traverse the vessel barrier, regenerate infarcted myocardium, and improve cardiac function  

PubMed Central

The ability of cardiac stem cells (CSCs) to promote myocardial repair under clinically relevant conditions (i.e., when delivered intravascularly after reperfusion) is unknown. Thus, rats were subjected to a 90-min coronary occlusion; at 4 h after reperfusion, CSCs were delivered to the coronary arteries via a catheter positioned into the aortic root. Echocardiographic analysis showed that injection of CSCs attenuated the increase in left ventricular (LV) end-diastolic dimensions and impairment in LV systolic performance at 5 weeks after myocardial infarction. Pathologic analysis showed that treated hearts exhibited a smaller increase in LV chamber diameter and volume and a higher wall thickness-to-chamber radius ratio and LV mass-to-chamber volume ratio. CSCs induced myocardial regeneration, decreasing infarct size by 29%. A diploid DNA content and only two chromosomes 12 were found in new cardiomyocytes, indicating that cell fusion did not contribute to tissue reconstitution. In conclusion, intravascular injection of CSCs after reperfusion limits infarct size, attenuates LV remodeling, and ameliorates LV function. This study demonstrates that CSCs are effective when delivered in a clinically relevant manner, a clear prerequisite for clinical translation, and that these beneficial effects are independent of cell fusion. The results establish CSCs as candidates for cardiac regeneration and support an approach in which the heart's own stem cells could be collected, expanded, and stored for subsequent therapeutic repair.

Dawn, Buddhadeb; Stein, Adam B.; Urbanek, Konrad; Rota, Marcello; Whang, Brian; Rastaldo, Raffaella; Torella, Daniele; Tang, Xian-Liang; Rezazadeh, Arash; Kajstura, Jan; Leri, Annarosa; Hunt, Greg; Varma, Jai; Prabhu, Sumanth D.; Anversa, Piero; Bolli, Roberto

2005-01-01

254

Echocardiography of the normal camel (Camelus dromedaries) heart: technique and cardiac dimensions  

PubMed Central

Background Echocardiography and intra-cardiac dimensions have not previously been reported in adult camels despite its potential application for medical purpose. The aim of this study was to describe the results of a prospective study, aiming to report normal cardiac appearance and normal chamber dimensions in adult camels (Camelus dromedarius). Results On the right side, when the probe was placed in the 5th or 4th intercostal space (ICS), the caudal long-axis four-chamber view of the ventricles, atria, and the interventricular septum was obtained. Placing the probe slightly more cranially in the 4th ICS, the caudal long-axis four-chamber view and the caudal long-axis view of the left ventricular outflow tract (LVOT) were imaged. In 7 camels, a hybrid view between a “four-chamber” and “LVOT view” was imaged from the same position. The short-axis view of the ventricles was obtained in the 4th ICS where the transducer was rotated between 0° and 25°. Placement of the transducer in the 3rd ICS allowed visualisation of the right ventricular outflow tract (RVOT). On the left side, when the probe was placed in the 5th or 4th ICS, a four-chamber view was obtained. The LVOT is imaged in the 4th ICS and the RVOT was seen from the 3rd ICS. Conclusions This study showed that it is possible to obtain good-quality echocardiograms in adult camels and provide normal cardiac dimensions. This study could be used as a reference for further studies concerning camels with cardiac diseases.

2012-01-01

255

Exercise training in patients with severe chronic heart failure: impact on left ventricular performance and cardiac size. A retrospective analysis of the Leipzig Heart Failure Training Trial  

Microsoft Academic Search

BackgroundExercise training (ET) has been shown to improve functional work capacity in patients with stable chronic heart failure (CHF) having moderate symptoms (NYHA class II). This analysis was conducted, to evaluate the effects of ET on left ventricular function and haemodynamics in patients with advanced CHF (NYHA class III) fulfilling the inclusion criteria of the COPERNICUS trial.MethodsSeventy-three patients with moderate

Sandra Erbs; Axel Linke; Stephan Gielen; Eduard Fiehn; Claudia Walther; Jiangtao Yu; Volker Adams; Gerhard Schuler; Rainer Hambrecht

2003-01-01

256

Relationship between mitral leaflets angles, left ventricular geometry and mitral deformation indices in patients with ischemic mitral regurgitation: imaging by echocardiography and cardiac magnetic resonance  

Microsoft Academic Search

Chronic ischemic mitral regurgitation (IMR) is associated with a markedly worse prognosis after myocardial infarction (MI).The\\u000a study aimed to evaluate the relationship between anterior and posterior mitral leaflet angle (MLA) values, left ventricle\\u000a remodeling and severity of ischaemic mitral regurgitation (IMR). Methods: Forty-two patients (age 63.5 ± 9.7 years, 36 men) with chronic IMR (regurgitant volume, RV > 20 ml; >6 months after MI)\\u000a underwent transthoracic echocardiography

Agata Lesniak-SobelgaEwa; Ewa Wicher-Muniak; Magdalena Kostkiewicz; Maria Olszowska; Piotr Musia?ek; Piotr Klimeczek; Pawe? Bany?; Mieczys?aw Pasowicz; Wies?awa Tracz; Piotr Podolec

257

Dynamic expression profiles of MMPs/TIMPs and collagen deposition in mechanically unloaded rat heart: implications for left ventricular assist device support-induced cardiac alterations.  

PubMed

Left ventricular assist devices (LVADs) ameliorate heart failure by reducing preload and afterload. However, extracellular matrix (ECM) deposition after application of LVADs is not clearly defined. The purpose of the present study was to investigate ECM remodeling after mechanical unloading in a rat heart transplant model. Sixty male Lewis rats were subjected to abdominal heterotopic heart transplantation, and the transplanted hearts were pressure- and volume-unloaded. The age- and weight- matched male Lewis rats who had undergone open thoracic surgeries were used as the control. Left ventricle ECM accumulation and the expression/activity of matrix metalloproteinases (MMPs) and tissue inhibitor of matrix metalloproteinases (TIMPs) were measured on the third, seventh, and fourteenth days after transplantation/sham surgery. Compared with the control group, myocardial ECM deposition significantly increased on the seventh and fourteenth days after heart transplantation (P < 0.05) and peaked on the 14th day. The gelatinase activity as well as mRNA expression of MMP-2 and MMP-9 significantly increased after transplantation (P < 0.05). Both mRNA and protein levels of TIMP-1 and TIMP-2 significantly increased compared with those of the control group. Mechanical unloading may lead to adverse remodeling of the ECM of the left ventricle. The underlying mechanism may due to the imbalance of the MMP/TIMP system, especially the remarkable upregulation of TIMPs in the pressure and volume unloaded heart. PMID:23315238

Wang, Lu; Xu, Yu-Xian; Du, Xiao-Jie; Sun, Quan-Ge; Tian, Ying-Jun

2013-09-01

258

A biplane roentgen videometry system for dynamic /60 per second/ studies of the shape and size of circulatory structures, particularly the left ventricle.  

NASA Technical Reports Server (NTRS)

A roentgen-television digital-computer technique and a display system developed for dynamic circulatory structure studies are described. Details are given for a videoroentgenographic setup which is used for obtaining biplane roentgen silhouettes of a left ventricle. A 60 per sec measurement of the shape and volume of angiographically outlined cardiac chambers can be made by this technique along with simultaneous ECG, pressure, and flow measurements accessible for real-time digital computer processing and analysis.

Ritman, E. L.; Sturm, E.; Wood, E. H.; Heintzen, P. H.

1971-01-01

259

Left atrial lesion formation and volume overload by open irrigation ablation technology during pulmonary vein antrum isolation: acute effects on cardiac hemodynamics  

Microsoft Academic Search

Purpose  Our goal was to evaluate acute effects of left atrial lesion formation and volume overload on hemodynamics during pulmonary\\u000a vein antrum isolation (PVAI) as it might be a potential cause of acute pulmonary edema.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  In consecutive patients presenting for PVAI, open irrigation ablation was performed (50 W, 48°C, 15 s lesion duration, saline\\u000a flow rate 30 mL\\/min). Blood samples were drawn from the

Georg Nölker; Klaus Jürgen Gutleben; Guido Ritscher; Harald Rittger; Stefan Asbach; Johannes Heintze; Bogdan Muntean; Jürgen Vogt; Johannes Brachmann; Dieter Horstkotte; Anil Martin Sinha

260

L-Arginine ameliorates cardiac left ventricular oxidative stress by upregulating eNOS and Nrf2 target genes in alloxan-induced hyperglycemic rats  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer L-Arginine treatment reduced the metabolic disturbances in diabetic animals. Black-Right-Pointing-Pointer Antioxidant marker proteins were found high in myocardium by L-arginine treatment. Black-Right-Pointing-Pointer Elevated antioxidant status, mediates the reduced TBA-reactivity in left ventricle. Black-Right-Pointing-Pointer L-Arginine treatment enhanced the Nrf2 and eNOS signaling in left ventricle. Black-Right-Pointing-Pointer Improved cell survival signaling by arginine, offers a novel tactic for targeting. -- Abstract: Hyperglycemia is independently related with excessive morbidity and mortality in cardiovascular disorders. L-Arginine-nitric oxide (NO) pathway and the involvement of NO in modulating nuclear factor-E2-related factor-2 (Nrf2) signaling were well established. In the present study we investigated, whether L-arginine supplementation would improve the myocardial antioxidant defense under hyperglycemia through activation of Nrf2 signaling. Diabetes was induced by alloxan monohydrate (90 mg kg{sup -1} body weight) in rats. Both non-diabetic and diabetic group of rats were divided into three subgroups and they were administered either with L-arginine (2.25%) or L-NAME (0.01%) in drinking water for 12 days. Results showed that L-arginine treatment reduced the metabolic disturbances in diabetic rats. Antioxidant enzymes and glutathione levels were found to be increased in heart left ventricles, thereby reduction of lipid peroxidation by L-arginine treatment. Heart histopathological analysis further validates the reversal of typical diabetic characteristics consisting of alterations in myofibers and myofibrillary degeneration. qRT-PCR studies revealed that L-arginine treatment upregulated the transcription of Akt and downregulated NF-{kappa}B. Notably, transcription of eNOS and Nrf2 target genes was also upregulated, which were accompanied by enhanced expression of Nrf2 in left ventricular tissue from diabetic and control rats. Under these findings, we suggest that targeting of eNOS and Nrf2 signaling by L-arginine supplementation could be used as a potential treatment method to alleviate the late diabetic complications.

Ramprasath, Tharmarajan; Hamenth Kumar, Palani; Syed Mohamed Puhari, Shanavas; Senthil Murugan, Ponniah; Vasudevan, Varadaraj [Molecular Cardiology Unit, Department of Biochemistry, Center for Excellence in Genomic Sciences, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, Tamilnadu (India)] [Molecular Cardiology Unit, Department of Biochemistry, Center for Excellence in Genomic Sciences, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, Tamilnadu (India); Selvam, Govindan Sadasivam, E-mail: drselvamgsbiochem@rediffmail.com [Molecular Cardiology Unit, Department of Biochemistry, Center for Excellence in Genomic Sciences, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021, Tamilnadu (India)

2012-11-23

261

Anomalous muscle bundles causing double-chambered right ventricle in adults.  

PubMed

Double-chambered right ventricle (DCRV) causing right ventricular outflow tract (RVOT) obstruction, is an uncommon cardiac disease especially when first diagnosed in adults. Diagnosis can be challenging when it is asymptomatic. We report a 40-year-old man who was referred to cardiology for work-up of a heart murmur that was found on a routine physical examination prior to obtaining a pilot's license. A transesophageal echocardiogram (TEE) revealed a DCRV and a small perimembranous ventricular septal defect (VSD) with left-to-right shunt and severe RVOT obstruction. Right heart catheterization showed an estimated gradient of 135 mm Hg across the two chambers due to subpulmonary stenosis. The pressure in the proximal right ventricular chamber was 160/25 mm Hg and 25/17 mm Hg in the distal chamber. Surgical correction was successfully performed. A postoperative TEE showed no residual gradients across the RVOT. DCRV has been reported as a rare disease in adults. It is difficult to diagnose DCRV using the transthoracic echocardiogram in adults. However, subcostal windows can offer better visualization of subpulmonary outflow tract compared to the parasternal and apical windows. TEE remains the main non-invasive modality for diagnosing DCRV in adults. Cardiac magnetic resonance imaging and invasive testing can provide further information to confirm the diagnosis and guide therapeutic decisions. PMID:24296393

Mohsen, Amr; Rahman, Faraaz; Ikram, Sohail

2013-12-01

262

Pericardial hydatid cyst presenting with cardiac tamponade  

PubMed Central

Cases of cardiac hydatid cyst disease are uncommon, occurring in approximately 0.5% to 2% of patients with hydatid disease. Most cardiac hydatid cysts are located in the left ventricle and interventricular septum. Cardiac involvement may have serious consequences. Both the disease and its surgical treatment carry a high complication rate, including rupture leading to cardiac tamponade, anaphylaxis and also death. In the present report, a 10-year-old girl with cardiac tamponade secondary to a pericardial hydatid cyst is described.

Kosecik, Mustafa; Karaoglanoglu, Mustafa; Yamak, Birol

2006-01-01

263

Hypoplastic left heart syndrome  

PubMed Central

Hypoplastic left heart syndrome(HLHS) refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch). Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision relative to treatment, and long-term prognosis as information on long-term survival and quality of life for those born with the syndrome is limited.

Connor, Jean Anne; Thiagarajan, Ravi

2007-01-01

264

Isolated congenital left ventricular diverticulum  

Microsoft Academic Search

Two cases of isolated left ventricular diverticulum are presented. A 12-year-old boy and a 7-year-old girl, both asymptomatic, were admitted to our Department for evaluation of an abnormal electrocardiogram and an abnormal cardiac silhouette, respectively. Both patients had the diagnosis confirmed by cardiac catheterization and angiography and underwent successful surgical correction of the abnormality. We discuss the diagnosis, prognosis, and

G. Pomé; G. Vignati; L. Mauri; M. Morello; A. Figini; A. Pellegrini

1995-01-01

265

Cardiac dysfunction in cirrhotic portal hypertension with or without ascites  

PubMed Central

Background Alteration of cardiovascular functions in patients with liver cirrhosis has been described and it correlates with severity of hepatic failure. But cardiac functions by conventional 2-dimensional (2-D) echocardiography has limitations. The aim of the study was to evaluate cardiac systolic and diastolic functions in liver cirrhosis patients with or without ascites by tissue Doppler imaging and conventional 2-D- echocardiography. Methods A cross sectional case control study of sixty patients. Twenty subjects grouped as healthy controls, pre-ascitic cirrhosis and cirrhosis with ascites were enrolled. Cardiac evaluation was done by both conventional Doppler and tissue Doppler echocardiography. Results Cirrhosis with portal hypertension is associated with increased heart rate, ejection fraction and mean peak systolic velocity, while mean arterial pressure is decreased. All cardiac chamber dilation occurs and is mostly seen in the left atrium. Ratio of early diastolic annular velocity to peak early diastolic annular wave velocity (E/e?) was the most significant marker for diastolic dysfunction. E/e? ratio was 7.76±0.40, 12.55±1.73 and 11.4±1.19 in healthy controls, pre ascitic cirrhosis and ascitic cirrhosis respectively (P<0.0001). Overall Type I and II Left ventricular diastolic dysfunction was present in 70% cirrhotic patient with or without ascites, while there were no cases of Type III (Severe) diastolic dysfunction. Conclusion Left ventricular diastolic dysfunction is commonly associated with advancement of hepatic dysfunction while systolic function is maintained till advanced hepatic failure. Peak early diastolic wave velocity, deceleration time and E/e’ ratio for left ventricular diastolic dysfunction are accurately assessed by pulsed tissue Doppler imaging.

Dadhich, Sunil; Goswami, Amitava; Jain, Vinit Kumar; Gahlot, Ankur; Kulamarva, Ganaraj; Bhargava, Narendra

2014-01-01

266

Ionization chamber  

DOEpatents

An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

Walenta, Albert H. (Port Jefferson Station, NY)

1981-01-01

267

Electrostatic Levitator Vacuum Chambers  

NASA Technical Reports Server (NTRS)

Optical prots ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (the beam passes through the window at left), poisitioning lasers (one port is at center), and lamps (such as the deuterium arc lamp at right), and to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

1998-01-01

268

Electrostatic Levitator Vacuum Chamber  

NASA Technical Reports Server (NTRS)

Optical prots ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (the beam passes through the window at left), poisitioning lasers (one port is at center), and lamps (arc lamp at right), and to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

1998-01-01

269

Electrostatic Levitator Vaccum Chamber  

NASA Technical Reports Server (NTRS)

Optical ports ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (the beam passes through the window at left), positioning lasers (one port is at center), and lamps (such as the deuterium arc lamp at right), and to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

1998-01-01

270

The impact of left ventricular preload reduction on cardiac pulsed Doppler indices during hemodialysis and its relation to intra-dialysis hypotension: a pulsed Doppler study.  

PubMed

Fluid status in the body plays an important role on left ventricular (LV) filling in patients with end-stage renal disease (ESRD) on regular hemodialysis (HD), and plays a role in intra-dialysis hemo-dynamic derangement. Fifty-two patients with ESRD on regular HD, including 34 males with a mean age of 45.5 +/- 13 years (range 18-72 years), were studied. All patients underwent Echo-pulsed Doppler study before and immediately after a HD session. The Echo Doppler indices noted were: LV cavity dimension and wall thickness, LV ejection fraction (LVEF%), trans-mitral early diastolic filling velocity (E wave), atrial filling diastolic velocity (A wave), E/A ratio, Deceleration Time (DT) of E wave, Isovolumic relaxation time (IVRT), Aortic Velocity Integral (AVI) and Inferior Vena Cava Diameter (VCD) at expiration. Patients were divided into two groups according to the amount of net ultra filtrate loss after HD. Group I comprised of 25 patients with fluid loss of > or = 2 liters. During the HD session, each patient was observed for the development of acute clinical events such as arterial hypotension (systolic BP less than 90 mmHg), chest pain and arrhythmias. There was a significant difference between the two groups in the mean values, pre- and post- HD, of reduction of E wave velocity (p< 0.01), the reduction of E/A ratio (p< 0.05), the increment in DT of E wave (p< 0.05), the reduction in AVI (p< 0.01) and the reduction of VCD (p< 0.05). There was no significant difference between the groups in the reduction of A wave velocity and the reduction of IVRT. Among the study patients, 11 (21%) developed systolic hypo-tension during HD. The pre-dialysis mean values of E/A ratio and DT of E wave in patients who developed hypotension compared to those who did not was 0.7 +/- 0.2 vs 1.1 +/- 0.2.1 (p< 0.001) and 246 +/- 40 vs 224 +/- 34 msec (p< 0.05), respectively. Our study suggests that preload reduction in patients with ESRD on regular HD is directly proportional to the reduction of left ventricle early filling and prolongation of Deceleration Time of E wave. The potential risk of intra-dialysis hypotension can be predicted, if LV diastolic Pulse Doppler pre-dialysis E/A ratio is less than 0.7 and Deceleration Time of E wave is more than 246 msec. Careful assess-ment of these patients is crucial to prevent hypotension, especially if a large preload reduction is required. PMID:19237804

Alarrayed, Sameer; Garadah, Taysir Said; Alawdi, Abdulhai Ali

2009-03-01

271

First Diagonal Coronary Artery: Left Ventricular Fistula Presenting as Unstable Angina  

PubMed Central

Coronary artery fistulae are characterized by communications between a coronary artery and a cardiac chamber or another vascular structure. They are usually congenital, but acquired forms may occur. Most patients are usually asymptomatic. However, some studies have emphasized that the incidence of symptoms and complications increases with age, particularly after the age of 20 (Liberthson et al. 1979, Hong et al. 2004). We aimed to present a very rare form of fistula originating from the first diagonal artery and connecting into the left ventricle.

Sener, Murat; Bilici, Muammer

2013-01-01

272

Genetic and Physiologic Dissection of the Vertebrate Cardiac Conduction System  

Microsoft Academic Search

Vertebrate hearts depend on highly specialized cardiomyocytes that form the cardiac conduction system (CCS) to coordinate chamber contraction and drive blood efficiently and unidirectionally throughout the organism. Defects in this specialized wiring system can lead to syncope and sudden cardiac death. Thus, a greater understanding of cardiac conduction development may help to prevent these devastating clinical outcomes. Utilizing a cardiac-specific

Neil C Chi; Robin M Shaw; Benno Jungblut; Jan Huisken; Tania Ferrer; Rima Arnaout; Ian Scott; Dimitris Beis; Tong Xiao; Herwig Baier; Lily Y Jan; Martin Tristani-Firouzi; Didier Y. R Stainier

2008-01-01

273

Automatic classification of scar tissue in late gadolinium enhancement cardiac MRI for the assessment of left-atrial wall injury after radiofrequency ablation  

NASA Astrophysics Data System (ADS)

Radiofrequency ablation is a promising procedure for treating atrial fibrillation (AF) that relies on accurate lesion delivery in the left atrial (LA) wall for success. Late Gadolinium Enhancement MRI (LGE MRI) at three months post-ablation has proven effective for noninvasive assessment of the location and extent of scar formation, which are important factors for predicting patient outcome and planning of redo ablation procedures. We have developed an algorithm for automatic classification in LGE MRI of scar tissue in the LA wall and have evaluated accuracy and consistency compared to manual scar classifications by expert observers. Our approach clusters voxels based on normalized intensity and was chosen through a systematic comparison of the performance of multivariate clustering on many combinations of image texture. Algorithm performance was determined by overlap with ground truth, using multiple overlap measures, and the accuracy of the estimation of the total amount of scar in the LA. Ground truth was determined using the STAPLE algorithm, which produces a probabilistic estimate of the true scar classification from multiple expert manual segmentations. Evaluation of the ground truth data set was based on both inter- and intra-observer agreement, with variation among expert classifiers indicating the difficulty of scar classification for a given a dataset. Our proposed automatic scar classification algorithm performs well for both scar localization and estimation of scar volume: for ground truth datasets considered easy, variability from the ground truth was low; for those considered difficult, variability from ground truth was on par with the variability across experts.

Perry, Daniel; Morris, Alan; Burgon, Nathan; McGann, Christopher; MacLeod, Robert; Cates, Joshua

2012-02-01

274

Prediction of fatal or near-fatal cardiac arrhythmia events in patients with depressed left ventricular function after an acute myocardial infarction†  

PubMed Central

Aims To determine whether risk stratification tests can predict serious arrhythmic events after acute myocardial infarction (AMI) in patients with reduced left ventricular ejection fraction (LVEF ? 0.40). Methods and results A total of 5869 consecutive patients were screened in 10 European centres, and 312 patients (age 65 ± 11 years) with a mean LVEF of 31 ± 6% were included in the study. Heart rate variability/turbulence, ambient arrhythmias, signal-averaged electrocardiogram (SAECG), T-wave alternans, and programmed electrical stimulation (PES) were performed 6 weeks after AMI. The primary endpoint was ECG-documented ventricular fibrillation or symptomatic sustained ventricular tachycardia (VT). To document these arrhythmic events, the patients received an implantable ECG loop-recorder. There were 25 primary endpoints (8.0%) during the follow-up of 2 years. The strongest predictors of primary endpoint were measures of heart rate variability, e.g. hazard ratio (HR) for reduced very-low frequency component (<5.7 ln ms2) adjusted for clinical variables was 7.0 (95% CI: 2.4–20.3, P < 0.001). Induction of sustained monomorphic VT during PES (adjusted HR = 4.8, 95% CI, 1.7–13.4, P = 0.003) also predicted the primary endpoint. Conclusion Fatal or near-fatal arrhythmias can be predicted by many risk stratification methods, especially by heart rate variability, in patients with reduced LVEF after AMI.

Huikuri, Heikki V.; Raatikainen, M.J. Pekka; Moerch-Joergensen, Rikke; Hartikainen, Juha; Virtanen, Vesa; Boland, Jean; Anttonen, Olli; Hoest, Nis; Boersma, Lucas V.A.; Platou, Eivind S.; Messier, Marc D.; Bloch-Thomsen, Poul-Erik

2009-01-01

275

Indexing cardiac parameters in echocardiographic practice: do estimates depend on how weight and height have been assessed? A study on left atrial dilatation.  

PubMed

We examined the difference between self-reported and measured height and weight in detecting echocardiographic left atrial dilatation (LAD), as defined by LA diameter indexed to body size parameters in an outpatient population referred to echocardiographic laboratories for routine examination. LAD was defined by 2 criteria: (1) LA diameter indexed to height greater than 24 mm/m; (2) LA diameter indexed to body surface area greater than 23 mm/m(2). Prevalence of LAD was calculated by indexing LA diameter to both self-reported and measured anthropometric values. In the whole population, LAD tended to be underestimated when LA diameter was indexed to self-reported compared with measured values, by 3.6% according to criterion 1 (26.4% versus 30.0%, P < .001) and by 0.6% according to criterion 2 (21.1% versus 21.6%, P = not significant). The difference between LAD estimates was more pronounced in older than in younger patients, either by criterion 1 (6.4% versus 1.6 %, P < .001) or by criterion 2 (2.1% versus 0.1%, P < .001). The error is related to demographic characteristics of patients and is more pronounced when LA diameter is normalized to height. PMID:21459069

Cuspidi, Cesare; Negri, Francesca; Muiesan, Maria Lorenza; Grandi, Anna Maria; Lonati, Laura; Ganau, Antonello; Degli Esposti, Daniela; Milan, Alberto; Sala, Carla; Facchetti, Rita; Mancia, Giuseppe

2011-01-01

276

Automatic cardiac contour propagation in short axis cardiac MR images  

Microsoft Academic Search

Active contours are a popular method for automatic extraction of object boundaries based on image features in medical images. However, in short axis cardiac MR images, they fail to give correct results due to the presence of papillary muscles along the left ventricular endocardium boundary. We propose a new automatic cardiac contour propagation method based on active contours. The method

G. L. T. F. Hautvast; M. Breeuwer; S. Lobregt; A. Vilanova; F. A. Gerritsen

2005-01-01

277

Left-ventricular non-compaction with congenital left ventricular diverticulum.  

PubMed

Left-ventricular non-compaction may be isolated or associated with other cardiac or noncardiac anomalies. Left-ventricular non-compaction associated with left ventricular diverticulum is very rare. We describe a 30 year-old pregnant woman with a long standing diagnosis of biventricular non-compaction in whom a hidden left ventricular apical diverticulum was detected on transthoracic echocardiography. Both these conditions increase the risk of thromboembolism. Additionally, she was also diagnosed to have endocervical adenocarcinoma. This case suggests that a comprehensive echocardiographic examination is mandatory in cases of suspected isolated left-ventricular non-compaction to detect any other associated cardiac or noncardiac anomalies. PMID:21856225

Panduranga, Prashanth; Thomas, Eapen; Al-Mukhaini, Mohammed

2012-04-01

278

Fractal analysis of heart rate dynamics as a predictor of mortality in patients with depressed left ventricular function after acute myocardial infarction. TRACE Investigators. TRAndolapril Cardiac Evaluation  

NASA Technical Reports Server (NTRS)

A number of new methods have been recently developed to quantify complex heart rate (HR) dynamics based on nonlinear and fractal analysis, but their value in risk stratification has not been evaluated. This study was designed to determine whether selected new dynamic analysis methods of HR variability predict mortality in patients with depressed left ventricular (LV) function after acute myocardial infarction (AMI). Traditional time- and frequency-domain HR variability indexes along with short-term fractal-like correlation properties of RR intervals (exponent alpha) and power-law scaling (exponent beta) were studied in 159 patients with depressed LV function (ejection fraction <35%) after an AMI. By the end of 4-year follow-up, 72 patients (45%) had died and 87 (55%) were still alive. Short-term scaling exponent alpha (1.07 +/- 0.26 vs 0.90 +/- 0.26, p <0.001) and power-law slope beta (-1.35 +/- 0.23 vs -1.44 +/- 0.25, p <0.05) differed between survivors and those who died, but none of the traditional HR variability measures differed between these groups. Among all analyzed variables, reduced scaling exponent alpha (<0.85) was the best univariable predictor of mortality (relative risk 3.17, 95% confidence interval 1.96 to 5.15, p <0.0001), with positive and negative predictive accuracies of 65% and 86%, respectively. In the multivariable Cox proportional hazards analysis, mortality was independently predicted by the reduced exponent alpha (p <0.001) after adjustment for several clinical variables and LV function. A short-term fractal-like scaling exponent was the most powerful HR variability index in predicting mortality in patients with depressed LV function. Reduction in fractal correlation properties implies more random short-term HR dynamics in patients with increased risk of death after AMI.

Makikallio, T. H.; Hoiber, S.; Kober, L.; Torp-Pedersen, C.; Peng, C. K.; Goldberger, A. L.; Huikuri, H. V.

1999-01-01

279

Cardiac function during breath-hold diving in humans: an echocardiographic study.  

PubMed

Breath-hold diving induces, in marine mammals, a reduction of cardiac output due to a decrease of both heart rate and stroke volume. Cardiovascular changes in humans during breath-hold diving are only partially known due to the technical difficulty of studying fully immersed subjects. Recently, a submersible echocardiograph has been developed, allowing a feasible assessment of cardiac anatomy and function of subjects during diving. Aim of the study was to evaluate, by Doppler-echocardiography, the cardiovascular changes inducedby breath-hold diving in humans. Ten male subjects were studied by Doppler echocardiography in dry conditions and during breath-hold diving at 3 m depth. In addition 14 male subjects were studied, using the same protocol, before and during breath-hold diving at 10 m depth. At 3 m depth significant reductions in heart rate (-17%), stroke volume (-17%), cardiac output (-29%), left atrial dimensions, and deceleration time of early diastolic transmitral flow (DTE) were observed. At 10 m depth similar but more pronounced changes occurred. In particular, increase in early transmitral flow velocity became significant (+33%), while DTE decreased by 34%. At both depths dimensions of right cardiac chambers remained unchanged. Breath-hold diving at shallow depth induced, in humans, cardiovascular changes qualitatively similar to those observed in natural divers such as seals. The reduced dimensions of left atrium associated to a left ventricular diastolic pattern resembling that of restrictive/constrictive heart disease, suggest that the hemodynamic effects of diving could be explained, at least in part, by a constriction exerted on the heart by the reduced chest volume and the increased blood content of the lungs. Finally, the absence of dimensional changes in the right chambers suggests that most of the pulmonary blood shift occurred before cardiac imaging. PMID:18500072

Marabotti, C; Belardinelli, A; L'Abbate, A; Scalzini, A; Chiesa, F; Cialoni, D; Passera, M; Bedini, R

2008-01-01

280

Magma chambers  

NASA Technical Reports Server (NTRS)

Recent observational and theoretical investigations of terrestrial magma chambers (MCs) are reviewed. Consideration is given to the evidence for MCs with active convection and crystal sorting, problems of direct MC detection, theoretical models of MC cooling, the rheology and dynamics of solidification fronts, crystal capture and differentiation, convection with solidification, MC wall flows, and MC roof melting. Diagrams, graphs, and a list of problems requiring further research are provided.

Marsh, Bruce D.

1989-01-01

281

Separation of afterload reduction and a direct beneficial cardiac effect of nifedipine in congestive cardiomyopathy.  

PubMed

To assess whether the calcium antagonist nifedipine has a specific, direct effect on left ventricular diastolic function separate from its vasodilatory action, we studied 10 patients with idiopathic congestive cardiomyopathy (ages 28-69, New York Heart Association Class III or IV) at 30 min, 2 h, and 6 h after administration of 10 mg of sublingual nifedipine. Hemodynamic parameters were assessed with Swan-Ganz catheter and two-dimensional echo images were processed with computer-assisted analysis (Quantic 1200) to obtain left ventricular chamber areas and an index of rapid diastolic filling. Indices of left ventricular systolic performance (cardiac index and left ventricular area change fraction) improved during the early (30 min and 2 h) observation periods as afterload (estimated by systolic blood pressure and systemic vascular resistance) was reduced (p less than .05 vs. baseline). Pulmonary capillary wedge pressure fell from 17 mmHg to 11 mmHg and rapid diastolic filling index increased from .28 (% area change/ms) to .37 (% area change/ms) (p less than .05 vs. baseline) during the early observation periods. Indices of left ventricular systolic performance and afterload had returned to baseline at the late (6 h) observation period. However, pulmonary capillary wedge pressure remained reduced significantly at 10 mmHg after 6 h (p less than .05 vs. baseline). Preload (estimated by left ventricular end-diastolic chamber area) did not vary throughout the study period. Reduction of pulmonary capillary wedge pressure at 6 h, despite return of afterload reduction to baseline and no change in preload, suggests improved left ventricular chamber compliance after sublingual nifedipine, not related to alteration of left ventricular loading conditions. PMID:2766589

Percy, R F; Bass, T A; Conetta, D A; Miller, A B

1989-08-01

282

A CMR study of the effects of tissue edema and necrosis on left ventricular dyssynchrony in acute myocardial infarction: implications for cardiac resynchronization therapy  

PubMed Central

Background In acute myocardial infarction (AMI), both tissue necrosis and edema are present and both might be implicated in the development of intraventricular dyssynchrony. However, their relative contribution to transient dyssynchrony is not known. Cardiovascular magnetic resonance (CMR) can detect necrosis and edema with high spatial resolution and it can quantify dyssynchrony by tagging techniques. Methods Patients with a first AMI underwent percutaneous coronary interventions (PCI) of the infarct-related artery within 24?h of onset of chest pain. Within 5–7?days after the event and at 4?months, CMR was performed. The CMR protocol included the evaluation of intraventricular dyssynchrony by applying a novel 3D-tagging sequence to the left ventricle (LV) yielding the CURE index (circumferential uniformity ratio estimate; 1?=?complete synchrony). On T2-weighted images, edema was measured as high-signal (>2 SD above remote tissue) along the LV mid-myocardial circumference on 3 short-axis images (% of circumference corresponding to the area-at-risk). In analogy, on late-gadolinium enhancement (LGE) images, necrosis was quantified manually as percentage of LV mid-myocardial circumference on 3 short-axis images. Necrosis was also quantified on LGE images covering the entire LV (expressed as %LV mass). Finally, salvaged myocardium was calculated as the area-at-risk minus necrosis (expressed as % of LV circumference). Results After successful PCI (n?=?22, 2 female, mean age: 57?±?12y), peak troponin T was 20?±?36ug/l and the LV ejection fraction on CMR was 41?±?8%. Necrosis mass was 30?±?10% and CURE was 0.91?±?0.05. Edema was measured as 58?±?14% of the LV circumference. In the acute phase, the extent of edema correlated with dyssynchrony (r2?=??0.63, p?

2012-01-01

283

Silencing of the Drosophila ortholog of SOX5 in heart leads to cardiac dysfunction as detected by optical coherence tomography.  

PubMed

The SRY-related HMG-box 5 (SOX5) gene encodes a member of the SOX family of transcription factors. Recently, genome-wide association studies have implicated SOX5 as a candidate gene for susceptibility to four cardiac-related endophenotypes: higher resting heart rate (HR), the electrocardiographic PR interval, atrial fibrillation and left ventricular mass. We have determined that human SOX5 has a highly conserved Drosophila ortholog, Sox102F, and have employed transgenic Drosophila models to quantitatively measure cardiac function in adult flies. For this purpose, we have developed a high-speed and ultrahigh-resolution optical coherence tomography imaging system, which enables rapid cross-sectional imaging of the heart tube over various cardiac cycles for the measurement of cardiac structural and dynamical parameters such as HR, dimensions and areas of heart chambers, cardiac wall thickness and wall velocities. We have found that the silencing of Sox102F resulted in a significant decrease in HR, heart chamber size and cardiac wall velocities, and a significant increase in cardiac wall thickness that was accompanied by disrupted myofibril structure in adult flies. In addition, the silencing of Sox102F in the wing led to increased L2, L3 and wing marginal veins and increased and disorganized expression of wingless, the central component of the Wnt signaling pathway. Collectively, the silencing of Sox102F resulted in severe cardiac dysfunction and structural defects with disrupted Wnt signaling transduction in flies. This implicates an important functional role for SOX5 in heart and suggests that the alterations in SOX5 levels may contribute to the pathogenesis of multiple cardiac diseases or traits. PMID:23696452

Li, Airong; Ahsen, Osman O; Liu, Jonathan J; Du, Chuang; McKee, Mary L; Yang, Yan; Wasco, Wilma; Newton-Cheh, Christopher H; O'Donnell, Christopher J; Fujimoto, James G; Zhou, Chao; Tanzi, Rudolph E

2013-09-15

284

Cardiac Resynchronization Pacing Therapy  

Microsoft Academic Search

Approximately one third of patients with congestive heart failure and systolic dysfunction have an intraventricular conduction delay that is manifested as a QRS duration >120 ms. An intraventricular conduction delay adversely affects ventricular performance by causing dyssynchrony in ventricular activation. When ventricular dyssynchrony is present, simultaneous left and right ventricular pacing or cardiac resynchronization therapy can improve ventricular synchrony. This

Cash Casey; Bradley P. Knight

2004-01-01

285

Left-ventricular diastolic dysfunction during pneumonectomy--a transesophageal echocardiographic study.  

PubMed

Left-ventricular dysfunction, with acute increase in capillary pulmonary pressure, can unexpectedly develop in patients submitted to pneumonectomy. In order to study the morphofunctional modifications induced by pneumonectomy on the left cardiac chambers, we performed intraoperative transesophageal echocardiography (TEE) in 8 patients (7 males, mean age 66 years) undergoing pneumonectomy for lung cancer. No patient had any cardiac involvement before surgery. The opening of the pericardium was associated with a slight paradoxical movement of the basal interventricular septum. After ligature of the pulmonary artery, the interventricular septum changed its geometry, losing the normal curvature and becoming rectilinear. These changes were related to an increase in right-ventricular (RV) dimensions. In all patients the pulmonary vein flow-profile (pulsed Doppler) showed an increased turbulence, associated with a reduced amplitude (5 patients) or an inversion (3 patients) of the second systolic component and with the development of mild mitral regurgitation (color Doppler). These changes disappeared at the end of intervention, before chest closure. No alteration in left-ventricular systolic function was found. These results suggest that the altered geometry of the interventricular septum, mainly due to acute RV overload, induces a transient left-ventricular diastolic dysfunction, associated with mild mitral regurgitation. PMID:8782335

Barletta, G; Del Bene, M R; Palminiello, A; Fantini, F

1996-04-01

286

Hypoplastic left heart syndrome  

Microsoft Academic Search

Opinion statement  \\u000a \\u000a \\u000a \\u000a \\u000a – \\u000a \\u000a Prenatal diagnosis of hypoplastic left heart syndrome is strongly encouraged through careful, routine level II ultrasound\\u000a screening, especially in highrisk families.\\u000a \\u000a \\u000a \\u000a \\u000a – \\u000a \\u000a A decision for palliative care (leading to death) should be discouraged if cardiac anatomy or physiology is favorable, centers\\u000a of expertise are available, sufficient resources exist, and there are no associated coexisting anomalies or genetic

Richard M. Donner

2000-01-01

287

Cardiac Hemangioma: A Case Report  

PubMed Central

Hemangioma of the heart, presenting as a primary cardiac tumor is extremely rare; it accounts for approximately 2% of all primary resected heart tumors. In our patient, the tumor was located in the orifice of the right lower pulmonary vein. Few cases of cardiac hemangiomas have been reported to arise from the left atrial (LA) wall. Left atrial hemangiomas, especially those attached to the LA wall, may be erroneously diagnosed as myxomas. Cardiac hemangioma is a rare disease; furthermore, a tumor arising from the LA wall and misconceived as a myxoma is extremely rare. We removed a mass misdiagnosed as a myxoma; it was pathologically confirmed to be a cardiac capillary hemangioma. Therefore, we report a rare case of a cardiac hemangioma misconceived as a myxoma; the tumor was removed successfully.

Hong, Sung-Yong; Park, Kyung-Taek; Lee, Yang-Haeng; Cho, Kwang-Hyun; Seo, Jeong-Sook

2014-01-01

288

Cardiac Magnetic Resonance Imaging Findings in 20-year Survivors of Mediastinal Radiotherapy for Hodgkin's Disease  

SciTech Connect

Purpose: The recognition of the true prevalence of cardiac toxicity after mediastinal radiotherapy requires very long follow-up and a precise diagnostic procedure. Cardiac magnetic resonance imaging (MRI) permits excellent quantification of cardiac function and identification of localized myocardial defects and has now been applied to a group of 20-year Hodgkin's disease survivors. Methods and materials: Of 143 patients treated with anterior mediastinal radiotherapy (cobalt-60, median prescribed dose 40 Gy) for Hodgkin's disease between 1978 and 1985, all 53 survivors were invited for cardiac MRI. Of those, 36 patients (68%) presented for MRI, and in 31 patients (58%) MRI could be performed 20-28 years (median, 24) after radiotherapy. The following sequences were acquired on a 1.5-T MRI: transversal T1-weighted TSE and T2-weighted half-fourier acquisition single-shot turbo-spin-echo sequences, a steady-state free precession (SSFP) cine sequence in the short heart axis and in the four-chamber view, SSFP perfusion sequences under rest and adenosine stress, and a SSFP inversion recovery sequence for late enhancement. The MRI findings were correlated with previously reconstructed doses to cardiac structures. Results: Clinical characteristics and reconstructed doses were not significantly different between survivors undergoing and not undergoing MRI. Pathologic findings were reduced left ventricular function (ejection fraction <55%) in 7 (23%) patients, hemodynamically relevant valvular dysfunction in 13 (42%), late myocardial enhancement in 9 (29%), and any perfusion deficit in 21 (68%). An association of regional pathologic changes and reconstructed dose to cardiac structures could not be established. Conclusions: In 20-year survivors of Hodgkin's disease, cardiac MRI detects pathologic findings in approximately 70% of patients. Cardiac MRI has a potential role in cardiac imaging of Hodgkin's disease patients after mediastinal radiotherapy.

Machann, Wolfram; Beer, Meinrad [Department of Radiology, University of Wuerzburg (Germany); Breunig, Margret; Stoerk, Stefan; Angermann, Christiane [Department of Cardiology, University of Wuerzburg (Germany); Seufert, Ines; Schwab, Franz; Koelbl, Oliver; Flentje, Michael [Department of Radiation Oncology, University of Wuerzburg (Germany); Vordermark, Dirk, E-mail: dirk.vordermark@medizin.uni-halle.d [Department of Radiation Oncology, University of Wuerzburg (Germany); Department of Radiation Oncology, Martin Luther University Halle-Wittenberg (Germany)

2011-03-15

289

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

PubMed

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. PMID:18502907

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

2008-07-01

290

Cardiac mechanics: Physiological, clinical, and mathematical considerations  

NASA Technical Reports Server (NTRS)

Recent studies concerning the basic physiological and biochemical principles underlying cardiac muscle contraction, methods for the assessment of cardiac function in the clinical situation, and mathematical approaches to cardiac mechanics are presented. Some of the topics covered include: cardiac ultrastructure and function in the normal and failing heart, myocardial energetics, clinical applications of angiocardiography, use of echocardiography for evaluating cardiac performance, systolic time intervals in the noninvasive assessment of left ventricular performance in man, evaluation of passive elastic stiffness for the left ventricle and isolated heart muscle, a conceptual model of myocardial infarction and cardiogenic shock, application of Huxley's sliding-filament theory to the mechanics of normal and hypertrophied cardiac muscle, and a rheological modeling of the intact left ventricle. Individual items are announced in this issue.

Mirsky, I. (editor); Ghista, D. N.; Sandler, H.

1974-01-01

291

Malignant phyllodes tumor of the left atrium  

PubMed Central

Metastatic tumors to the heart usually involve right sided chambers. We report a rare case of malignant phyllodes tumor of breast with metastatic involvement of left atrium occurring through direct invasion from mediastinal micro-metastasis and presenting as a left atrial mass causing arrhythmia.

Bhambhani, Anupam; Ayyagari, Sudha; Mohapatra, Tushar; Rehman, Syed Abdul; Shah, Milap; Rao, Sudhakar; Rangashamanna, Vital; Rajasekhar, V.; Chittimilla, Santosh

2014-01-01

292

Wire chambers revisited.  

PubMed

Detectors used for radioisotope imaging have, historically, been based on scintillating crystal/photomultiplier combinations in various forms. From the rectilinear scanner through to modern gamma cameras and positron cameras, the basic technology has remained much the same. Efforts to overcome the limitations of this form of technology have foundered on the inability to reproduce the required sensitivity, spatial resolution and sensitive area at acceptable cost. Multiwire proportional chambers (MWPCs) have long been used as position-sensitive charged particle detectors in nuclear and high-energy physics. MWPCs are large-area gas-filled ionisation chambers in which large arrays of fine wires are used to measure the position of ionisation produced in the gas by the passage of charged particles. The important properties of MWPCs are high-spatial-resolution, large-area, high-count-rate performance at low cost. For research applications, detectors several metres square have been built and small-area detectors have a charged particle resolution of 0.4 mm at a count rate of several million per second. Modification is required to MWPCs for nuclear medicine imaging. As gamma rays or X-rays cannot be detected directly, they must be converted into photo- or Compton scatter electrons. Photon-electron conversion requires the use of high atomic number materials in the body of the chamber. Pressurised xenon is the most useful form of "gas only" photon-electron convertor and has been used successfully in a gamma camera for the detection of gamma rays at energies below 100 keV. This camera has been developed specifically for high-count-rate first-pass cardiac imaging. This high-pressure xenon gas MWPC is the key to a highly competitive system which can outperform scintillator-based systems. The count rate performance is close to a million counts per second and the intrinsic spatial resolution is better than the best scintillator-based camera. The MWPC camera produces quantitative ejection fraction information of the highest quality. The detection of higher energy gamma rays has proved more problematical, needing a solid photon-electron convertor to be incorporated into the chamber. Several groups have been working on this problem with modest success so far. The only clinical detectors have been developed for positron emission tomography, where thin lead or lead-glass can provide an acceptable convertor for 511 keV photons. Two MWPC positron cameras have been evaluated clinically and one is now in routine use in clinical oncology. The problems of detection efficiency have not been solved by these detectors although reliability and large-area PET imaging have been proven.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8491229

Ott, R J

1993-04-01

293

Angiotensin II signaling up-regulates the immediate early transcription factor ATF3 in the left but not the right atrium  

PubMed Central

The atria respond to various pathological stimuli including pressure and volume overload with remodeling and dilatation. Dilatation of the left atrium is associated with atrial fibrillation. The mechanisms involved in chamber-specific hypertrophy are largely unknown. Angiotensin II is hypothesized to take part in mediating this response. ATF3 is an immediate early gene found at the receiving end of multiple stress and growth stimuli. Here we characterize ATF3 as a direct target gene for angiotensin II. ATF3 expression is regulated by angiotensin receptor-mediated signaling in vivo and in vitro at the transcriptional level. ATF3 induction is mediated by cooperation between both the AT1A and AT2 receptor subtypes. While AT2R blocker (PD123319) efficiently blocks ATF3 induction in response to angiotensin II injection, it results in an increase in blood pressure indicating that the effect of angiotensin II on ATF3 is independent of its effect on blood pressure. In contrast to adrenergic stimulation that induces ATF3 in all heart chambers, ATF3 induction in response to angiotensin II occurs primarily in the left chambers. We hypothesize that the activation of differential signaling pathways accounts for the chamber-specific induction of ATF3 expression in response to angiotensin II stimulation. Angiotensin II injection rapidly activates the EGFR-dependent pathways including ERK and PI3K-AKT in the left but not the right atrium. EGF receptor inhibitor (Gefitinib/Iressa) as well as the AKT inhibitor (Triciribine) significantly abrogates ATF3 induction by angiotensin II in the left chambers. Collectively, our data strongly place ATF3 as a unique nuclear protein target in response to angiotensin II stimulation in the atria. The spatial expression of ATF3 may add to the understanding of the signaling pathways involved in cardiac response to neuro-hormonal stimulation, and in particular to the understanding of left atrial-generated pathology such as atrial fibrillation.

Hasin, Tal; Elhanani, Ofer; Abassi, Zaid; Hai, Tsonwin

2013-01-01

294

Plaque vulnerability of coronary artery lesions is related to left ventricular dilatation as determined by optical coherence tomography and cardiac magnetic resonance imaging in patients with type 2 diabetes  

PubMed Central

Background Patients with type 2 diabetes are at increased risk for both, left ventricular (LV)-dilatation and myocardial infarction (MI) following the rupture of a vulnerable plaque. This study investigated the to date incompletely understood relationship between plaque vulnerability and LV-dilatation using optical coherence tomography (OCT) and cardiac magnetic resonance imaging (CMR) in patients with type 2 diabetes and stable coronary artery disease. Methods CMR was performed in 58 patients with type 2 diabetes, in which 81 coronary lesions were investigated using OCT. Results A decreased minimal fibrous cap thickness (FCT) of coronary lesions was associated with an increase of several CMR-derived parameters including LV-end diastolic volume (LVEDV, r?=?0.521, p?

2013-01-01

295

[Functional coupling of the left ventriculo-arterial system and aging in man].  

PubMed

In a haemodynamic and angiographic study at rest conducted in 25 men aged from 22 to 68 years who had no more than another risk factor for arterial disease and showed no evidence of cardiac or arterial disease several parameters were measured or calculated. Firstly, a global index of arterial system function (Ea) and its various factors: Ea = ESP/SV [ESP: left ventricular end-systolic pressure; SV: systolic volume]; Ea = (HR x TSR)+Ea' [HR: heart rate/min; TSR: total systemic resistance] where Ea' = (ESP - AoP/SV) [AoP: mean aortic pressure]. Secondly, the parameters concerning the left ventricle were the mass (m) and the m/EDV ratio [EDV: end-diastolic volume] and indices of the left ventricular systolic and diastolic functions, such as ELV = ESP/ESV [ESV: end-systolic volume], kp: the volumic distensibility module of the left ventricular chamber; relations EF - o ES [EF: ejection fraction; o ES: end-systolic constraint], and kp - m/EDV as indice of left ventricular muscle distensibility. In parallel with the subjects' age, Ea increased by joint augmentation of TSR and Ea' while m, m/EDV, ELV and kp also significantly increased. The inotropic quality of the left ventricular muscle and its intrinsic distensibility were found to be decreased in a few subjects aged over 45. Ea/ELV (reverse of ejection fraction -1) tended to increase (ELV relatively less than Ea), but this increase was not significant (P = 0.10). These results show that in the ageing man the improvement observed in the ejection fraction of the left ventricular pump corresponds roughly to the degradation of the arterial system transfer function, and the arterial system-left ventricle coupling, evaluated by the Ea/ELV ratio, is maintained (better in fact than in arterial hypertension and heart failure). This improvement is achieved by increases of m and, chiefly, m/EDV which compensate for both the increase of Ea and the relative decline of left ventricular muscle contractile quality. There is a disorder of the left ventricular pump diastolic function which is due to geometric changes in the chamber and to changes in the intrinsic distensibility of the left ventricular muscle. PMID:1409476

Dahan, M; Mérillon, J P; Cohen-Solal, A; Paillole, C; Guiomard, A; Gourgon, R

1992-07-22

296

Left superior vena cava: revisited.  

PubMed

The persistence of a left-sided superior vena cava is the most common variant of systemic venous drainage. Increased utility of cardiac imaging, in particular cross-sectional techniques such as computed tomography and magnetic resonance (MR), will result in increased detection of the anomaly and its variants. Whilst in the typical form it is often haemodynamically insignificant, its discovery may have clinical significance nonetheless, and its mimics require exclusion. During cardiac development the anomaly results from a failure of the left anterior cardinal vein to obliterate. Recognized anatomical variants include the absence of the right superior vena cava and of an innominate bridging vein. Typical drainage is to the coronary sinus, dilatation of which may be the first hint to the anomaly. Clinical implications with respect to vascular access and arrhythmia are well described. A significant minority drain into the left atrium, potentially creating a haemodynamically significant lesion. Additionally, differentiation from anomalous left upper pulmonary venous drainage via a vertical vein is mandatory. A newly discovered variant runs an intra-atrial course with subsequent typical drainage, and if not recognized as such, may be confused with a left atrial mass. The use of 3D contrast-enhanced MR venography has proven extremely helpful in characterizing anomalous vasculature, and we demonstrate how such techniques can help delineate the anomaly and differentiate from its mimics. PMID:22301985

Irwin, R B; Greaves, M; Schmitt, M

2012-04-01

297

Two-ventricle repair for hypoplastic left heart syndrome  

Microsoft Academic Search

Hypoplastic left heart syndrome encompasses a spectrum of structural cardiac malformations characterized by severe underdevelopment of the structures in the left heart-aorta complex. The severe end of the spectrum consists of aortic atresia and mitral atresia, whereas at the mild end patients have aortic valve and mitral valve hypoplasia without intrinsic valve stenosis, recently described as hypoplastic left heart complex.

Christo I. Tchervenkov

2001-01-01

298

Fibroblast-mediated pathways in cardiac hypertrophy.  

PubMed

Under normal physiological conditions, cardiac fibroblasts are the primary producers of extracellular matrix and supply a mechanical scaffold for efficacious heart contractions induced by cardiomyocytes. In the hypertrophic heart, cardiac fibroblasts provide a pivotal contribution to cardiac remodeling. Many growth factors and extracellular matrix components secreted by cardiac fibroblasts induce and modify cardiomyocyte hypertrophy. Recent evidence revealed that cardiomyocyte-cardiac fibroblast communications are complex and multifactorial. Many growth factors and molecules contribute to cardiac hypertrophy via different roles that include induction of hypertrophy and the feedback hypertrophic response, fine-tuning of adaptive hypertrophy, limitation of left ventricular dilation, and modification of interstitial changes. This review focuses on recent work and topics and provides a mechanistic insight into cardiomyocyte-cardiac fibroblast communication in cardiac hypertrophy. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium ". PMID:24492068

Fujiu, Katsuhito; Nagai, Ryozo

2014-05-01

299

Infected cardiac myxoma.  

PubMed

A 66-year-old male presenting with low-grade fever and general fatigue was diagnosed as having infected myxoma of the left atrium. Blood cultures grew Streptococcus mitis. He underwent urgent resection and histological examination revealed tumor cells in a mucopolysaccharide matrix and bacterial colonies along with active inflammation. Infected cardiac myxoma is extremely rare; however, it contains a potential risk of arterial embolization and so early diagnosis and urgent surgery should be considered. PMID:23931763

Nagata, Tomoki; Totsugawa, Toshinori; Katayama, Keijiro; Kuinose, Masahiko; Yoshitaka, Hidenori; Uesugi, Tadahisa

2013-11-01

300

Portable Hyperbaric Chamber  

NASA Technical Reports Server (NTRS)

A portable, collapsible hyperbaric chamber was developed. A toroidal inflatable skeleton provides initial structural support for the chamber, allowing the attendant and/or patient to enter the chamber. Oval hatches mate against bulkhead rings, and the hyperbaric chamber is pressurized. The hatches seal against an o-ring, and the internal pressure of the chamber provides the required pressure against the hatch to maintain an airtight seal. In the preferred embodiment, the hyperbaric chamber has an airlock to allow the attendant to enter and exit the patient chamber during treatment. Visual communication is provided through portholes in the patient and/or airlock chamber. Life monitoring and support systems are in communication with the interior of the hyperbaric chamber and/or airlock chamber through conduits and/or sealed feed-through connectors into the hyperbaric chamber.

Schneider, William C. (Inventor); Locke, James P. (Inventor); DeLaFuente, Horacio (Inventor)

2001-01-01

301

Evaluation of cardiac emboli source  

PubMed Central

Background Evaluating the source of cardiac embolism is one of the most frequent reasons for cardiac consultation. Methods In 2003, 99 patients were referred for the evaluation of the source of cardiac emboli. Evaluation included history, physical examination, ECG, transoesophageal echocardiography (TOE) with contrast and 24-hour Holter electrocardiography. Results Altogether, 58 men and 41 women were studied. In 32 patients a possible source of the cardiac emboli was found. Two patients were in atrial fibrillation. Of the patients, 16 had a patent foramen ovale (PFO) and six patients a PFO and atrial septum aneurysm (ASA). Two patients had a thrombus in the left atrial appendage and 14 had severe atherosclerosis in the aortic arch. In eight patients we found two possible cardiac sources of embolism. 24-hour Holter recording did not detect any emboligenic arrhythmias. Conclusion A possible cardiac source of embolism was found in 32% of the patients referred. TOE is the ideal tool to visualise the interatrial septum, left atrial appendage and aortic arch. We advise performing a TOE with contrast in young stroke patients and in older patients with a stroke likely to be caused by an embolism of cardiac origin. 24-hour Holter recording did not detect any emboligenic arrhythmias and should only be done in selected cases. ImagesFigure 1Figure 2

Michels, M.; Meijboom, F.J.; ten Cate, F.J.

2005-01-01

302

Growth and remodeling of the left ventricle: A case study of myocardial infarction and surgical ventricular restoration  

PubMed Central

Cardiac growth and remodeling in the form of chamber dilation and wall thinning are typical hallmarks of infarct-induced heart failure. Over time, the infarct region stiffens, the remaining muscle takes over function, and the chamber weakens and dilates. Current therapies seek to attenuate these effects by removing the infarct region or by providing structural support to the ventricular wall. However, the underlying mechanisms of these therapies are unclear, and the results remain suboptimal. Here we show that myocardial infarction induces pronounced regional and transmural variations in cardiac form. We introduce a mechanistic growth model capable of predicting structural alterations in response to mechanical overload. Under a uniform loading, this model predicts non-uniform growth. Using this model, we simulate growth in a patient-specific left ventricle. We compare two cases, growth in an infarcted heart, pre-operative, and growth in the same heart, after the infarct was surgically excluded, post-operative. Our results suggest that removing the infarct and creating a left ventricle with homogeneous mechanical properties does not necessarily reduce the driving forces for growth and remodeling. These preliminary findings agree conceptually with clinical observations.

Klepach, Doron; Lee, Lik Chuan; Wenk, Jonathan F.; Ratcliffe, Mark B.; Zohdi, Tarek I.; Navia, Jose A.; Kassab, Ghassan S.; Kuhl, Ellen; Guccione, Julius M.

2012-01-01

303

Using a human cardiovascular-respiratory model to characterize cardiac tamponade and pulsus paradoxus  

Microsoft Academic Search

BACKGROUND: Cardiac tamponade is a condition whereby fluid accumulation in the pericardial sac surrounding the heart causes elevation and equilibration of pericardial and cardiac chamber pressures, reduced cardiac output, changes in hemodynamics, partial chamber collapse, pulsus paradoxus, and arterio-venous acid-base disparity. Our large-scale model of the human cardiovascular-respiratory system (H-CRS) is employed to study mechanisms underlying cardiac tamponade and pulsus

Deepa Ramachandran; Chuan Luo; Tony S Ma; John W Clark Jr

2009-01-01

304

8. EMPTY LOCK CHAMBER FROM DOWNSTREAM (WEST) END, WITH VISITORS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. EMPTY LOCK CHAMBER FROM DOWNSTREAM (WEST) END, WITH VISITORS CENTER (LEFT) AND LOCKMASTER'S HOUSE ON NORTH BANK. VIEW TO NORTHEAST. - Starved Rock Locks & Dam, Illinois Waterway River mile 231, Peru, La Salle County, IL

305

Detection of Cardiac Variability in the Isolated Rat Heart  

Microsoft Academic Search

Cardiac variability can be assessed from two perspectives: beat-to-beat performance and continuous performance during the cardiac cycle. Linear analysis techniques assess cardiac variability by measuring the physical attributes of a signal, whereas nonlinear techniques evaluate signal dynamics. This study sought to determine if recurrence quantification analysis (RQA), a nonlinear technique, could detect pharmacologically induced autonomic changes in the continuous left

Autumn M. Schumacher; Joseph P. Zbilut; Charles L. Webber; Dorie W. Schwertz; Mariann R. Piano

2006-01-01

306

A hammock in the left atrium.  

PubMed

Shone's anomaly describes a complex involving multiple left sided cardiac obstructions, namely, parachute deformity of the mitral valve, supravalvular ring of the left atrium, subaortic stenosis and aortic coarctation. We are reporting a case of Shone's anomaly characterised by aortic recoarctation, mitral supravalvular membrane, bicuspid aortic valve, complicated complete atrioventricular block and bradycardia-induced nonsustained polymorphic ventricular tachycardia. We revealed mitral supravalvular membrane by 3D transoesophageal echocardiography. PMID:21316305

Guler, Ahmet; Aung, Soe Moe; Kargin, Ramazan; Bitigen, Atilla; Ozdemir, Nihal

2011-08-01

307

Left Ventricular Rupture Post Mitral Valve Replacement  

PubMed Central

Prevention is better than cure best applies here. As per many authors, posterior leaflet chordae preservation prevent Left ventricular rupture (LVR) and preserve LV geometry. We are presenting here 5 types of left ventricular rupture (LVR) post Mitral valve replacement (MVR) with different methods to repair with the advantages and disadvantages of each. The mortality rate is still very high despite the advances in cardiac surgery. Many therapeutic approaches have been adopted. Yet, none is ideal.

Sersar, Sameh I.; Jamjoom, Ahmed A.

2009-01-01

308

The development of septation in the four-chambered heart.  

PubMed

The past decades have seen immense progress in the understanding of cardiac development. Appreciation of precise details of cardiac anatomy, however, has yet to be fully translated into the more general understanding of the changing structure of the developing heart, particularly with regard to formation of the septal structures. In this review, using images obtained with episcopic microscopy together with scanning electron microscopy, we show that the newly acquired information concerning the anatomic changes occurring during separation of the cardiac chambers in the mouse is able to provide a basis for understanding the morphogenesis of septal defects in the human heart. It is now established that as part of the changes seen when the heart tube changes from a short linear structure to the looped arrangement presaging formation of the ventricles, new material is added at both its venous and arterial poles. The details of these early changes, however, are beyond the scope of our current review. It is during E10.5 in the mouse that the first anatomic features of septation are seen, with formation of the primary atrial septum. This muscular structure grows toward the cushions formed within the atrioventricular canal, carrying on its leading edge a mesenchymal cap. Its cranial attachment breaks down to form the secondary foramen by the time the mesenchymal cap has used with the atrioventricular endocardial cushions, the latter fusion obliterating the primary foramen. Then the cap, along with a mesenchymal protrusion that grows from the mediastinal mesenchyme, muscularizes to form the base of the definitive atrial septum, the primary septum itself forming the floor of the oval foramen. The cranial margin of the foramen is a fold between the attachments of the pulmonary veins to the left atrium and the roof of the right atrium. The apical muscular ventricular septum develops concomitant with the ballooning of the apical components from the inlet and outlet of the ventricular loop. Its apical part is initially trabeculated. The membranous part of the septum is derived from the rightward margins of the atrioventricular cushions, with the muscularizing proximal outflow cushions fusing with the muscular septum and becoming the subpulmonary infundibulum as the aorta is committed to the left ventricle. Perturbations of these processes explain well the phenotypic variants of deficient atrial and ventricular septation. Anat Rec, 297:1414-1429, 2014. © 2014 Wiley Periodicals, Inc. PMID:24863187

Anderson, Robert H; Spicer, Diane E; Brown, Nigel A; Mohun, Timothy J

2014-08-01

309

Left ventricular remodelling, and systolic and diastolic function in young adults with ? thalassaemia major: a Doppler echocardiographic assessment and correlation with haematological data  

PubMed Central

Objective: To evaluate left ventricular morphology and function in a large population of patients with ? thalassaemia. Design: Echo Doppler assessment of left ventricular function and correlation of cardiovascular data with haematological data. Setting: Thalassaemia unit in a tertiary referral centre. Patients: 197 young adults with ? thalassaemia, following an adequate transfusional and chelation treatment regimen, without clinical signs of cardiopulmonary involvement. The control group consisted of 213 healthy subjects. Results: Left ventricular volumes, mass index, and mass/volume ratio were increased. Diastolic and systolic shapes were different, the left ventricle maintaining an ellipsoidal shape. The ejection fraction was reduced, and was < 50% in 33 patients. Stroke volume and cardiac index were increased, and systemic vascular resistance was decreased. Fractional shortening and mean velocity of circumferential shortening were decreased. Meridional end systolic and peak systolic stress were increased, as was circumferential end systolic stress. The contractile state was reduced while the functional preload index did not differ. Left ventricular diastolic function, evaluated from the mitral inflow, showed a slightly prolonged isovolumic relaxation time, increased flow velocity integrals, and an increased E/A ratio. Among the haematological data, only serum ferritin showed a weak negative correlation with left ventricular ejection fraction. The patients with the highest serum ferritin (> 2500 ng/ml) had the lowest ejection fraction. Conclusions: Patients with ? thalassaemia on an adequate transfusion and chelation treatment regimen show abnormal left ventricular remodelling with increased volumes, mass, and mass/volume ratio. Systolic chamber function and contractile state are reduced, with a slightly increased afterload. These findings seem mainly to be related to the increased cardiac output caused by chronic anaemia. Left ventricular performance is better preserved when chelation treatment is adjusted to maintain the serum ferritin concentration at < 1000 ng/ml.

Bosi, G; Crepaz, R; Gamberini, M R; Fortini, M; Scarcia, S; Bonsante, E; Pitscheider, W; Vaccari, M

2003-01-01

310

Single ventricle cardiac defect.  

PubMed

Single ventricle heart is defined as a rare cardiac abnormality with a single ventricle chamber involving diverse functional and physiological defects. Our case is of a ten month-old baby boy who died shortly after admission to the hospital due to vomiting and diarrhoea. Autopsy findings revealed cyanosis of finger nails and ears. Internal examination revealed; large heart, weighing 60 grams, single ventricle, without a septum and upper membranous part. Single ventricle is a rare pathology, hence, this paper aims to discuss this case from a medico-legal point of view. PMID:20527615

Eren, Bulent; Turkmen, Nursel; Turkmen, Nurset; Fedakar, Recep; Senel, Berna; Cetin, Volkan; Cetin, Volkn

2010-05-01

311

7. SEDIMENTATION CHAMBER AT 520', CONSTRUCTED 19371938, VIEWED FROM DOWNSTREAM. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. SEDIMENTATION CHAMBER AT 520', CONSTRUCTED 1937-1938, VIEWED FROM DOWNSTREAM. DEBRIS REMOVED FROM TOP PLANKS FOR CLARITY. ONE OF TWO SPILLWAYS SEEN AT RIGHT. FLUSH VALVE SEEN AT LOWER LEFT AND WRENCH FOR VALVES IS PROPPED AGAINST CHAMBER. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

312

Left Atrium Papillary Fibroelastomas: A Cause of Cerebral Emboli  

PubMed Central

Papillary fibroelastomas are cardiac benign tumours. Among the benign cardiac tumor, papillary fibroelastomas are reported second after myxomas. Most often diagnosed incidentally, papillary fibroelastomas may embolize to cerebral circulation. Valvular locations are predominant; location in left atrium is rare. In this paper, we present a case of papillary fibroelastoma located in left atrium with symptoms of cerebral embolization. Transoesophageal echocardiography diagnosed a mobile mass. The patient was treated with surgical resection without further embolic complication.

Ciss, A. G.; Ba, P. S.; Dieng, P. A.; Azarnoush, K.; Camilleri, L.; Geoffroy, E.; Innorta, A.; Legault, B.; Cosserant, B.; de Riberolles, C.; N'diaye, M.

2012-01-01

313

Congenital Heart Surgery Nomenclature and Database Project: hypoplastic left heart syndrome  

Microsoft Academic Search

Hypoplastic left heart syndrome (HLHS) encompasses a spectrum of structural cardiac malformations that are characterized by severe underdevelopment of the structures in the left heart-aorta complex, including the left ventricular cavity and mass. The severe end of the spectrum consists of aortic atresia and mitral atresia with a nonexistent left ventricle, whereas at the mild end patients have aortic valve

Christo I Tchervenkov; Marshall L Jacobs; Stephen A Tahta

2000-01-01

314

Absent right and persistent left superior vena cava: troubleshooting during a challenging pacemaker implant: a case report  

PubMed Central

Background Venous anomalies of the thorax can occur in isolation or in association with complex congenital heart disease. The incidence of an absent right superior vena cava in the setting of a persistent left superior vena cava is very rare in the general population with only a dozen cases documented in the medical literature. Such venous anomalies can make for very challenging electronic cardiac device implantation. We report our challenging dual chamber pacemaker implant in a patient with such complex anatomy and focus on our implantation technique that helped achieve adequate lead positioning. Case presentation A 73-year-old Caucasian female with degenerative complete heart block presented for dual chamber permanent pacemaker implant. Lead implantation was very challenging due to abnormal and rare vena cava anatomy; a persistent left superior vena cava drained directly into the coronary sinus and the right brachiocephalic vein drained directly into the left persistent superior vena cava as the patient had an absent right superior vena cava . Adequate right ventricular lead positioning was achieved following numerous lead-stylet manipulations and careful looping in the atria to redirect its trajectory to the ventricular apex. Conclusion Abnormal superior vena cava development is uncommon and can lead to technical challenges when venous access is required during various interventional procedures. Pre-operative imaging can help identify such challenging anatomy allowing appropriate operative planning; careful patient selection is warranted for venography given the risk of contrast nephrotoxicity.

2014-01-01

315

Aerospike Thrust Chamber Program.  

National Technical Information Service (NTIS)

An existing, but damaged, 25,000-pound thrust, flightweight, oxygen/hydrogen aerospike rocket thrust chamber was disassembled and partially repaired. A description is presented of the aerospike chamber configuration and of the damage it had suffered. Tech...

J. Campbell S. M. Cobb

1976-01-01

316

Unbiased stratification of left ventricles.  

PubMed

Image based quantitative stratification of the Left Ventricles (LV) across a population helps in unraveling the structure-function symbiosis of the heart. An unbiased, reference less grouping scheme that automatically determines the number of clusters and a physioanatomically relevant strategy that aligns the intra cluster LV shapes would enable the robust construction of pathology stratified cardiac atlas. This paper achieves this hitherto elusive stratification and alignment by adapting the conventional strategies routinely followed by clinicians. The individual LV shape models (N=127) are independently oriented to an "attitudinally consistent orientation" that captures the physioanatomic variations of the LV morphology. Affinity propagation technique based on the automatically identified inter-LV_landmark distances is used to group the LV shapes. The proposed algorithm is computationally efficient and, if the inter cluster variations are linked to pathology, could provide a clinically relevant cardiac atlas. PMID:18979790

Srinivasan, Rajagopalan; Shriram, K S; Suryanarayanan, Srikanth

2008-01-01

317

A multimodal (MRI/ultrasound) cardiac phantom for imaging experiments  

NASA Astrophysics Data System (ADS)

A dynamic cardiac phantom can play a significant role in the evaluation and development of ultrasound and cardiac magnetic resonance (MR) motion tracking and registration methods. A four chamber multimodal cardiac phantom has been designed and built to simulate normal and pathologic hearts with different degrees of "infarction" and "scar tissues". In this set up, cardiac valves have been designed and modeled as well. The four-chamber structure can simulate the asymmetric ventricular, atrial and valve motions. Poly Vinyl Alcohol (PVA) is used as the principal material since it can simulate the shape, elasticity, and MR and ultrasound properties of the heart. The cardiac shape is simulated using a four-chamber mold made of polymer clay. An additional pathologic heart phantom containing stiff inclusions has been manufactured in order to simulate an infracted heart. The stiff inclusions are of different shapes and different degrees of elasticity and are able to simulate abnormal cardiac segments. The cardiac elasticity is adjusted based on freeze-thaw cycles of the PVA cryogel for normal and scarred regions. Ultrasound and MRI markers were inserted in the cardiac phantom as landmarks for validations. To the best of our knowledge, this is the first multimodal phantom that models a dynamic four-chamber human heart including the cardiac valve.

Tavakoli, Vahid; Kendrick, Michael; Shakeri, Mostafa; Alshaher, Motaz; Stoddard, Marcus F.; Amini, Amir

2013-03-01

318

About Cardiac Arrest  

MedlinePLUS

... High Blood Pressure Tools & Resources Stroke More About Cardiac Arrest Updated:Nov 25,2013 What is cardiac arrest? ... content was last reviewed on 02/26/2013. Cardiac Arrest • Home • About Cardiac Arrest • Warning Signs for Cardiac ...

319

Persistent left superior vena cava draining into the left atrium.  

PubMed

A 40-year-old man was admitted with necrotising fasciitis of the right thigh. Further workup to evaluate for an infectious source revealed an incidental finding of persistent left superior vena cava via transesophageal echocardiography. This finding was confirmed by cardiac MRI. During his hospitalisation, he also developed altered mental status which was found to be secondary to systemic emboli by a head MRI. The primary source of infection was likely his dental abscesses. He underwent intravenous antibiotic therapy for a total of 6 weeks and was then referred to a specialised vascular centre for further management of his congenital anomaly. PMID:23978521

Tobbia, Patrick; Norris, Leslie A; Lane, Timothy

2013-01-01

320

Old Riverdale Cotton Mill office building on left. The old ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Old Riverdale Cotton Mill office building on left. The old office building has also been used as a starch mixing house. Note entrance to new office building on right - Riverdale Cotton Mill, Office Building, Old, Valley, Chambers County, AL

321

9. VIEW OF WEST (left) AND EAST (right) WALLS, LOOKING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. VIEW OF WEST (left) AND EAST (right) WALLS, LOOKING NORTH WITH COFFER DAM IN BACKGROUND--August 1980, during repairs - Willamette Falls Lock Chamber No.1, Willamette River, West Linn, Clackamas County, OR

322

Equations for estimating muscle fiber stress in the left ventricular wall.  

PubMed

Left ventricular muscle fiber stress is an important parameter in cardiac energetics. Hence, we developed equations for estimating regional fiber stresses in rotationally symmetric chambers, and equatorial and apical fiber stresses in prolate spheroidal chambers. The myocardium was modeled as a soft incompressible material embedding muscle fibers that support forces only in their longitudinal direction. A thin layer of muscle fibers then contributes with a pressure increment determined by the fiber stress and curvature. The fiber curvature depends on the orientation of the fibers, which varies continuously across the wall. However, by assuming rotational symmetry about the long axis of the ventricle and including a longitudinal force balance, we obtained equations where fiber stress is completely determined by the principal curvatures of the middle wall surface, wall thickness, and cavity pressure. The equations were validated against idealized prolate spheroidal chambers, whose wall thicknesses are such that the fiber stress is uniform from the equator to the apex. Because the apex is free to rotate, the resultant moment about the long axis of the LV must be zero. By using this constraint together with our fiber-stress equations, we were able to estimate a muscle fiber orientation distribution across the wall that was in qualitative agreement with published measurements. PMID:10776823

Rabben, S I; Irgens, F; Angelsen, B

1999-01-01

323

Hyperphysics: The Cloud Chamber  

NSDL National Science Digital Library

This Hyperphysics webpage contains a short description of the Wilson cloud chamber and two photographs by Wilson himself of cloud chamber tracks. Links provides information about various methods of detecting radiation and also about the muon, an elementary particle that was first detected in a cloud chamber. The text on this page is written at a level of a student of introductory physics.

Nave, Carl R.

2008-11-26

324

Two chamber reaction furnace  

DOEpatents

A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

Blaugher, Richard D. (Evergreen, CO)

1998-05-05

325

Two chamber reaction furnace  

DOEpatents

A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

Blaugher, R.D.

1998-05-05

326

The Clinical Benefits of Adding a Third Dimension to Assess the Left Ventricle with Echocardiography  

PubMed Central

Three-dimensional echocardiography is a novel imaging technique based on acquisition and display of volumetric data sets in the beating heart. This permits a comprehensive evaluation of left ventricular (LV) anatomy and function from a single acquisition and expands the diagnostic possibilities of noninvasive cardiology. It provides the possibility of quantitating geometry and function of LV without preestablished assumptions regarding cardiac chamber shape and allows an echocardiographic assessment of the LV that is less operator-dependent and therefore more reproducible. Further developments and improvements for widespread routine applications include higher spatial and temporal resolution to improve image quality, faster acquisition, processing and reconstruction, and fully automated quantitative analysis. At present, three-dimensional echocardiography complements routine 2DE in clinical practice, overcoming some of its limitations and offering additional valuable information that has led to recommending its use for routine assessment of the LV of patients in whom information about LV size and function is critical for their clinical management.

Badano, Luigi P.

2014-01-01

327

An unusual case of cardiac tamponade: ruptured subaortic diverticulum.  

PubMed

Cardiac diverticula are rare congenital anomalies found as outpouchings from various chambers of the heart. We present a case of a diverticulum arising from the membranous septum with free rupture into the pericardial space and tamponade. PMID:20345853

Salemi, Arash; Lee, Ben; Ivascu, Natalia; Webber, Geoffrey; Paul, Subroto

2010-05-01

328

Automated region mask for four-chamber fetal heart biometry.  

PubMed

This letter proposes an automated region mask for the detection of cardiac chambers from ultrasonic fetal heart biometry. The fetal biometry consists of two dimensional ultrasonic cine-loop sequences of apical four chamber view of fetal heart, which are comparatively The clinical motion information of individual frame is extracted by keeping a constant frame rate of 25 frames per second (fps). The region mask is designed based on the superimposition of motion information from a set of consecutive frames that belong to one cardiac cycle followed by connected component labelling. The borders and edges of all four chambers are thus recognized leading to formation of binary region mask. Experimental study based on second trimester cine-loop sequences confirms the suitability of the proposed technique for detection of heart chambers. PMID:23085836

Vijayalakshmi, S; Sriraam, N; Suresh, S; Muttan, S

2013-04-01

329

Association between Circulating Fibroblast Growth Factor 23, ?-Klotho, and the Left Ventricular Ejection Fraction and Left Ventricular Mass in Cardiology Inpatients  

PubMed Central

Background Fibroblast growth factor 23 (FGF23), with its co-receptor Klotho, plays a crucial role in phosphate metabolism. Several recent studies suggested that circulating FGF23 and ?-Klotho concentrations might be related to cardiovascular abnormalities in patients with advanced renal failure. Purpose Using data from 100 cardiology inpatients who were not undergoing chronic hemodialysis, the association of circulating levels of FGF23, ?-Klotho, and other calcium-phosphate metabolism-related parameters with the left ventricular ejection fraction (LVEF) and left ventricular mass (LVM) was analyzed. Methods and Results LVEF was measured using the modified Simpson method for apical 4-chamber LV images and the LVM index (LVMI) was calculated by dividing the LVM by body surface area. Univariate analysis showed that log transformed FGF23, but not that of ?-Klotho, was significantly associated with LVEF and LVMI with a standardized beta of ?0.35 (P<0.001) and 0.26 (P<0.05), respectively. After adjusting for age, sex, estimated glomerular filtration rate, and serum concentrations of intact parathyroid hormone, and 25-hydroxyvitamin D as covariates into the statistical model, log-transformed FGF23 was found to be a statistically positive predictor for decreased left ventricular function and left ventricular hypertrophy. Conclusions In cardiology department inpatients, circulating FGF23 concentrations were found to be associated with the left ventricular mass and LVEF independent of renal function and other calcium-phosphate metabolism-related parameters. Whether modulation of circulating FGF23 levels would improve cardiac outcome in such a high risk population awaits further investigation.

Shibata, Kensaku; Fujita, Shu-ichi; Morita, Hideaki; Okamoto, Yusuke; Sohmiya, Koichi; Hoshiga, Masaaki; Ishizaka, Nobukazu

2013-01-01

330

Future easy and physiological cardiac pacing  

PubMed Central

The right atrial appendage (RAA) and right ventricular apex (RVA) have been widely considered as conventional sites for typical dual-chamber atrio-ventricular cardiac (DDD) pacing. Unfortunately conventional RAA pacing seems not to be able to prevent atrial fibrillation in DDD pacing for tachycardia-bradycardia syndrome, and the presence of a left bundle branch type of activation induced by RVA pacing can have negative effects. A new technology with active screw-in leads permits a more physiological atrial and right ventricular pacing. In this review, we highlight the positive effects of pacing of these new and easily selected sites. The septal atrial lead permits a shorter and more homogeneous atrial activation, allowing better prevention of paroxysmal atrial fibrillation. The para-Hisian pacing can be achieved in a simpler and more reliable way with respect to biventricular pacing and direct Hisian pacing. We await larger trials to consider this “easy and physiological pacing” as a first approach in patients who need a high frequency of pacing.

Occhetta, Eraldo; Bortnik, Miriam; Marino, Paolo

2011-01-01

331

[Technology of hyperbaric chambers].  

PubMed

Technical requirements for hyperbaric chambers are subject to permanent change. Medical gas supplies, the chamber hulls, control systems, medical equipment as well as the security check-up modalities have been constantly adapted according to the most recent technical developments. Moreover, different subtypes of hyperbaric chambers such as treatment facilities, chambers used for training purposes or facilities set up for primary experimental use require specific technical outfit. Keeping in mind some recent tragic accidents in hyperbaric facilities, chamber security is of foremost importance. Alarm- as well as technical monitoring systems, fire-fighting equipment, deluge systems and pressure locks are absolute requirements for any hyperbaric chamber. In chambers used for therapeutic purposes the possibility of invasive and noninvasive patient monitoring as well as hygienic standards have to be ensured. PMID:11315411

Smolle-Jüttner, F M

1999-01-01

332

Partial aortic valve fusion induced by left ventricular assist device  

Microsoft Academic Search

Background. Left ventricular assist devices (LVADs) may be used (1) as a bridging device to cardiac transplantation, (2) for permanent replacement of left ventricular function, and (3) as a bridge to recovery of ventricular function, for example, in recoverable myocardial disease. In this third group of patients, it is important that the LVAD does not produce changes in the heart

Alan G Rose; Soon J Park; Alan J Bank; Leslie W Miller

2000-01-01

333

Doxorubicin cardiomyopathy in children with left-sided Wilms tumor  

Microsoft Academic Search

Two children with Wilms tumor of the left kidney experienced severe anthracycline cardiomyopathy after irradiation to the tumor bed and conventional dosage of doxorubicin. The cardiomyopathy is attributed 1) to the fact that radiation fields for left Wilms tumor include the lower portion of the heart and 2) to the interaction of doxorubicin and irradiation on cardiac muscle. It is

D. Pinkel; B. Camitta; L. Kun; C. Howarth; T. Tang

1982-01-01

334

Impact of heart failure and left ventricular systolic dysfunction on quality of life. A cross-sectional study comparing common chronic cardiac and medical disorders and a representative adult population  

Microsoft Academic Search

Background Heart failure and left ventricular systolic dysfunction (LVSD) are increasingly common disorders, with outcomes worse than many cancers. Evidence-based therapies, such as ACE inhibitors and beta-blockers, improve prognosis and symptoms, and reduce healthcare expenditure. However, despite the high prevalence and malignant prognosis, few studies have reported the impact of heart failure and LVSD on overall quality of life and,

F. D. R. Hobbs; J. E. Kenkre; A. K. Roalfe; R. C. Davis; R. Hare; M. K. Davies

2002-01-01

335

Cardiac factors in orthostatic hypotension  

NASA Astrophysics Data System (ADS)

Cardiac function is determined by preload, afterload, heart rate and contractility. During orthostatic stress, the footward blood shift is compensated for by an increase of afterload. LBNP is widely used to analyze effects of volume displacement during orthostatic stress. Comparisons of invasive ( right heart catheterization) and non-invasive approach (echocardiography) yielded similar changes. Preload and afterload change with graded LBNP, heart rate increases, and stroke volume and cardiac output decrease. Thus, the working point on the left ventricular function curve is shifted to the left and downward, similar to hypovolemia. However, position on the Frank-Starling curve, the unchanged ejection fraction, and the constant Vcf indicate a normal contractile state during LBNP. A decrease of arterial oxygen partial pressure during LBNP shwos impaired ventilation/perfusion ratio. Finally, LBNP induced cardiac and hemodynamic changes can be effectively countermeasured by dihydroergotamine, a potent venoconstrictor. Comparison of floating catheter data with that of echocardiography resulted in close correlation for cardiac output and stroke volume. In addition, cardiac dimensions changed in a similar way during LBNP. From our findings, echocardiography as a non-invasive procedure can reliably used in LBNP and orthostatic stress tests. Some informations can be obtained on borderline values indicating collaps or orthostatic syncope. Early fainters can be differentiated from late fainters by stroke volume changes.

Löllgen, H.; Dirschedl, P.; Koppenhagen, K.; Klein, K. E.

336

Cardiac outflow tract anomalies  

PubMed Central

The mature outflow tract (OFT) is, in basic terms, a short conduit. It is a simple, although vital, connection situated between contracting muscular heart chambers and a vast embryonic vascular network. Unfortunately, it is also a focal point underlying many multifactorial congenital heart defects (CHDs). Through the use of various animal models combined with human genetic investigations, we are beginning to comprehend the molecular and cellular framework that controls OFT morphogenesis. Clear roles of neural crest cells (NCC) and second heart field (SHF) derivatives have been established during OFT formation and remodeling. The challenge now is to determine how the SHF and cardiac NCC interact, the complex reciprocal signaling that appears to be occurring at various stages of OFT morphogenesis, and finally how endocardial progenitors and primary heart field (PHF) communicate with both these colonizing extra-cardiac lineages. Although we are beginning to understand that this dance of progenitor populations is wonderfully intricate, the underlying pathogenesis and the spatiotemporal cell lineage interactions remain to be fully elucidated. What is now clear is that OFT alignment and septation are independent processes, invested via separate SHF and cardiac neural crest (CNC) lineages. This review will focus on our current understanding of the respective contributions of the SHF and CNC lineage during OFT development and pathogenesis.

Neeb, Zachary; Lajiness, Jacquelyn D.; Bolanis, Esther; Conway, Simon J

2014-01-01

337

Abnormal Origin of the Left Subclavian Artery from the Left Pulmonary Artery in a Patient with Double Outlet Right Ventricle  

PubMed Central

Anomalous aortic origin of the left subclavian artery (LSCA) from the left pulmonary artery (LPA) is a rare congenital cardiac malformation. We describe a case of LSCA from the LPA via ductus arteriosus in association with a double-outlet right ventricle, which never has been reported previously in Korea.

Hong, Seong Wook

2014-01-01

338

Dual chamber pacemaker implants--a new opportunity in Pakistan for children with congenital and acquired complete heart block  

Microsoft Academic Search

Implantation of cardiac pacemakers has been practiced for at least five decades with continuous developments of the hardware. The invention of dual chamber pacemakers has initiated a debate concerning its superiority over single chamber ventricular pacemakers. Throughout the world, surgeons have been using dual chambered permanent pacemakers with successful follow ups. However, Pakistan has not yet taken the advantage of

Awais Ashfaq; Mansoor Ahmed Khan; Mehnaz Atiq; Muhammad Muneer Amanullah

2011-01-01

339

Cardiac compartment-specific overexpression of a modified retinoic acid receptor produces dilated cardiomyopathy and congestive heart failure in transgenic mice.  

PubMed Central

Retinoids play a critical role in cardiac morphogenesis. To examine the effects of excessive retinoid signaling on myocardial development, transgenic mice that overexpress a constitutively active retinoic acid receptor (RAR) controlled by either the alpha- or beta-myosin heavy chain (MyHC) promoter were generated. Animals carrying the alpha-MyHC-RAR transgene expressed RARs in embryonic atria and in adult atria and ventricles, but developed no signs of either malformations or disease. In contrast, beta-MyHC-RAR animals, where expression was activated in fetal ventricles, developed a dilated cardiomyopathy that varied in severity with transgene copy number. Characteristic postmortem lesions included biventricular chamber dilation and left atrial thrombosis; the incidence and severity of these lesions increased with increasing copy number. Transcript analyses showed that molecular markers of hypertrophy, alpha-skeletal actin, atrial natriuretic factor and beta-MyHC, were upregulated. Cardiac performance of transgenic hearts was evaluated using the isolated perfused working heart model as well as in vivo, by transthoracic M-mode echocardiography. Both analyses showed moderate to severe impairment of left ventricular function and reduced cardiac contractility. Thus, expression of a constitutively active RAR in developing atria and/ or in postnatal ventricles is relatively benign, while ventricular expression during gestation can lead to significant cardiac dysfunction.

Colbert, M C; Hall, D G; Kimball, T R; Witt, S A; Lorenz, J N; Kirby, M L; Hewett, T E; Klevitsky, R; Robbins, J

1997-01-01

340

Left-to-Right Shunt with Congenital Heart Disease: Single Center Experience  

PubMed Central

Objective. The objective of this study was to determine the frequency of pulmonary arterial hypertension (PAH) in congenital heart disease (CHD) with an isolated, large left-to-right shunt and to indicate the factors in the development of PAH. Methods. The pressure measurements in the cardiac chambers and the calculations based on the Fick's principle were compared among 3 separate groups of patients, respectively, with PAH, with hyperkinetic pulmonary hypertension (HPH), and with neither PAH nor HPH. Results. PAH was diagnosed in 30 (12.3%) patients, HPH in 35 (14.4%), while 177 (73.1%) were free of either. The highest risk for the development of PAH was found in the presence of perimembranous ventricular septal defect. A statistically significant difference was seen among these groups as to their left atrial pressure (p = 0.005) and the mean pulmonary arterial pressure (PAPmean; p < 0.001). While a correlation was present between RpI on one hand and age on the other (p = 0.014), a multiple linear regression could not evidence any correlation among age (p = 0.321), gender (p = 0.929). Conclusion. Our findings do not allow establishing a correlation between the duration of the high pulmonary flow and pulmonary vascular resistance increase or PAH development in isolated left-to-right shunts with congenital heart diseases.

Cevik, Ayhan; Olgunturk, Rana; Kula, Serdar; Saylan, Berna; Pektas, Ayhan; Oguz, Deniz; Tunaoglu, Sedef

2013-01-01

341

Cardiac Ochronosis  

PubMed Central

We report the case of 67-year-old woman who underwent aortic valve replacement and mitral valve repair due to ochronotic valvular disease (alkaptonuria), which was diagnosed incidentally during cardiac surgery.

Erek, Ersin; Casselman, Filip P.A.; Vanermen, Hugo

2004-01-01

342

Cardiac catheterization  

MedlinePLUS

... amyloidosis Causes of congestive heart failure or cardiomyopathy Coronary artery disease Heart defects that are present at birth ( ... include: Cardiac tamponade Heart attack Injury to a coronary artery Irregular heartbeat Low blood pressure Reaction to the ...

343

Cardiac Rehabilitation  

MedlinePLUS

Cardiac rehabilitation (rehab) is a medically supervised program to help people who have A heart attack Angioplasty or coronary artery bypass grafting for coronary heart disease A heart valve repair or replacement A ...

344

Cardiac MRI  

MedlinePLUS

... from the NHLBI on Twitter. What Is Cardiac MRI? Magnetic resonance imaging (MRI) is a safe, noninvasive test that creates detailed ... and no instruments are inserted into your body. MRI uses radio waves, magnets, and a computer to ...

345

Cardiac Angiosarcoma  

PubMed Central

Despite cardiac metastases are found in about 20% of cancer deaths, the presence of primary cardiac tumors is rare. Most primary tumors are benign, and malignant tumors comprise about 15%. We report a 21-year-old man with fever, dyspnea, and hemoptysis that was diagnosed with angiosarcoma of the right atrium and pulmonary metastasis. Patient was submitted to surgical tumor resection without adjuvant therapy and died four months after diagnosis.

Cardoso, Monique Esteves; Canale, Leonardo Secchin; Ramos, Rosana Grandelle; Salvador Junior, Edson da Silva; Lachtermacher, Stephan

2011-01-01

346

Doxorubicin cardiomyopathy in children with left-sided Wilms tumor  

SciTech Connect

Two children with Wilms tumor of the left kidney experienced severe anthracycline cardiomyopathy after irradiation to the tumor bed and conventional dosage of doxorubicin. The cardiomyopathy is attributed 1) to the fact that radiation fields for left Wilms tumor include the lower portion of the heart and 2) to the interaction of doxorubicin and irradiation on cardiac muscle. It is recommended that doxorubicin dosage be sharply restricted in children with Wilms tumor of the left kidney who receive postoperative irradiation.

Pinkel, D.; Camitta, B.; Kun, L.; Howarth, C.; Tang, T.

1982-01-01

347

Frequency-dependent left ventricular performance in women and men.  

PubMed

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. PMID:22467313

Wainstein, Rodrigo V; Sasson, Zion; Mak, Susanna

2012-06-01

348

Medical altitude chamber  

US Patent & Trademark Office Database

The medical altitude chamber is constituted by a pressuretight therapeutic chamber communicating with a source of a gas medium under pressure. It also incorporates apparatus for moistening the gas medium in the therapeutic chamber, said apparatus comprising a liquid reservoir whose lower part communicates through an adjustable throttle with the internal space of the jet pump nozzle, and a pressure regulator which has an inlet for communication with the source of the gas medium, a setting inlet for communication with the therapeutic chamber, and an outlet for communication with the upper part of the liquid reservoir.

1979-08-28

349

Cardiac surgery for arrhythmias.  

PubMed

Cardiac arrhythmia surgery was initiated in 1968 with the first successful division of an accessory AV connection for the Wolff-Parkinson-White Syndrome. Subsequent surgical procedures included the left atrial isolation procedure and the right atrial isolation procedure for automatic atrial tachycardias, discrete cryosurgery of the AV node for AV nodal reentry tachycardia, the atrial transection procedure, corridor procedure and Maze procedure for atrial fibrillation, the right ventricular disconnection procedure for arrhythmogenic right ventricular tachycardia, the encircling endocardial ventriculotomy, subendocardial resection procedure, endocardial cryoablation, the Jatene procedure, and the Dor procedure for ischemic ventricular tachycardia. Because of monumental strides in the treatment of most refractory arrhythmias by endocardial catheter techniques during the past decade, the only remaining viable surgical procedures for cardiac arrhythmias are the Maze procedure for atrial fibrillation and the Dor procedure for ischemic ventricular tachycardia. Nevertheless, the 25-30 years of intense activity in the field of cardiac arrhythmia surgery provided the essential foundation for the development of these catheter techniques and represent one of the most exciting and productive eras in the history of medicine. In one short professional career, we have witnessed the birth of arrhythmia surgery, its adolescence as an "esoteric" specialty, its prime as an enlightening yet exhausting period, and finally its waning years as a source of knowledge and wisdom on which better methods of treatment have been founded. One could hardly ask for a more rewarding experience. PMID:23570110

Cox, James L

2004-11-01

350

Cardiac surgery for arrhythmias.  

PubMed

Cardiac arrhythmia surgery was initiated in 1968 with the first successful division of an accessory AV connection for the Wolff-Parkinson-White Syndrome. Subsequent surgical procedures included the left atrial isolation procedure and the right atrial isolation procedure for automatic atrial tachycardias, discrete cryosurgery of the AV node for AV nodal reentry tachycardia, the atrial transection procedure, corridor procedure and Maze procedure for atrial fibrillation, the right ventricular disconnection procedure for arrhythmogenic right ventricular tachycardia, the encircling endocardial ventriculotomy, subendocardial resection procedure, endocardial cryoablation, the Jatene procedure, and the Dor procedure for ischemic ventricular tachycardia. Because of monumental strides in the treatment of most refractory arrhythmias by endocardial catheter techniques during the past decade, the only remaining viable surgical procedures for cardiac arrhythmias are the Maze procedure for atrial fibrillation and the Dor procedure for ischemic ventricular tachycardia. Nevertheless, the 25-30 years of intense activity in the field of cardiac arrhythmia surgery provided the essential foundation for the development of these catheter techniques and represent one of the most exciting and productive eras in the history of medicine. In one short professional career, we have witnessed the birth of arrhythmia surgery, its adolescence as an "esoteric" specialty, its prime as an enlightening yet exhausting period, and finally its waning years as a source of knowledge and wisdom on which better methods of treatment have been founded. One could hardly ask for a more rewarding experience. PMID:14764186

Cox, James L

2004-02-01

351

Cardiac surgery for arrhythmias.  

PubMed

Cardiac arrhythmia surgery was initiated in 1968 with the first successful division of an accessory AV connection for the Wolff-Parkinson-White syndrome. Subsequent surgical procedures included the left atrial isolation procedure and right atrial isolation procedure for automatic atrial tachycardias, discrete cryosurgery of the AV node for AV nodal reentrant tachycardia, the atrial transection procedure, the corridor procedure, and the maze procedure for atrial fibrillation, the right ventricular disconnection procedure for arrhythmogenic right ventricular tachycardia, and the encircling endocardial ventriculotomy, subendocardial resection procedure, endocardial cryoablation, the Jatene procedure, and the Dor procedure for ischemic ventricular tachycardia. Because of monumental strides in the treatment of most refractory arrhythmias by endocardial catheter techniques during the past decade, the only remaining viable surgical procedures for cardiac arrhythmias are the maze procedure for atrial fibrillation and the Dor procedure for ischemic ventricular tachycardia. Nevertheless, the 25 to 30 years of intense activity in the field of cardiac arrhythmia surgery provided the essential foundation for the development of these catheter techniques and represent one of the most exciting and productive eras in the history of medicine. In one short professional career, we have witnessed the birth of arrhythmia surgery, its adolescence as an "esoteric" specialty, its prime as an enlightening yet exhausting period, and finally its waning years as a source of knowledge and wisdom upon which better methods of treatment have been founded. One could hardly ask for a more rewarding experience. PMID:15028063

Cox, James L

2004-02-01

352

Chamber Formation and Morphogenesis in the Developing Mammalian Heart  

Microsoft Academic Search

In this study we challenge the generally accepted view that cardiac chambers form from an array of segmental primordia arranged along the anteroposterior axis of the linear and looping heart tube. We traced the spatial pattern of expression of genes encoding atrial natriuretic factor, sarcoplasmic reticulum calcium ATPase, Chisel, Irx5, Irx4, myosin light chain 2v, and ?-myosin heavy chain and

Vincent M. Christoffels; Petra E. M. H. Habets; Diego Franco; Marina Campione; Frits de Jong; Wouter H. Lamers; Zheng-Zheng Bao; Steve Palmer; Christine Biben; Richard P. Harvey; Antoon F. M. Moorman

2000-01-01

353

Computational Model for Early Cardiac Looping  

Microsoft Academic Search

Looping is a vital event during early cardiac morphogenesis, as the initially straight heart tube bends and twists into a curved tube, laying out the basic pattern of the future four-chambered heart. Despite intensive study for almost a century, the biophysical mechanisms that drive this process are not well understood. To explore a recently proposed hypothesis for looping, we constructed

Ashok Ramasubramanian; Kimberly S. Latacha; Jessica M. Benjamin; Dmitry A. Voronov; Arvind Ravi; Larry A. Taber

354

Computational Model for Early Cardiac Looping  

Microsoft Academic Search

Looping is a vital event during early cardiac morphogenesis, as the initially straight heart tube bends and twists into a curved tube, laying out the basic pattern of the future four-chambered heart. Despite intensive study for almost a century, the biophysical mechanisms that drive this process are not well understood. To explore a recently proposed hypothesis for looping, we constructed

Ashok Ramasubramanian; Kimberly S. Latacha; Jessica M. Benjamin; Dmitry A. Voronov; Arvind Ravi; Larry A. Taber

2006-01-01

355

Isolated, broad-based apical diverticulum: cardiac magnetic resonance is a "terminator" of cardiac imaging modality for the evaluation of cardiac apex.  

PubMed

In spite of the frequent involvement of many cardiac diseases, it is difficult to evaluate the left ventricular apex in detail with transthoracic echocardiography, a first-line imaging modality in cardiovascular diseases, because the apex is very closely located at the echocardiographic probe. Cardiac magnetic resonance enables us to evaluate the cardiac apex without any limitation to the image acquisition. We here present a case regarding a broad-based apical diverticulum, which was initially confused with apical aneurysm. PMID:24255656

Ahn, Hyo-Suk; Kim, Hyung-Kwan; Park, Eun-Ah; Lee, Whal; Park, Jae-Hyung; Sohn, Dae-Won

2013-10-01

356

Left ventricular endomyocardial fibrosis in India.  

PubMed

Clinical, radiological, electrocardiographic, haemodynamic, and cineangiographic features of left ventricular endomyocardial fibrosis are described in 8 patients seen during the 10-year period 1965-1975. Exertional dyspnoea was the commonest presenting symptom. Mild to moderate cardiomegaly was often present. The apex beat was never forcible. A loud third heart sound over the apex and an apical early systolic murmur with late systolic decresendo were characteristic of this desease. Chest X-rays films showed left atrial enlargement and pulmonary venous congestion. A pronounced rise in left ventricular end-diastolic pressure, severe pulmonary hypertension, and low cardiac index were seen in 6. Ventriculography showed an irregular, poorly contracting left ventricle with areas of dyskinesis and large end-systolic volume. Mitral regurgitation, when present, was not severe. PMID:861100

Vijayaraghavan, G; Cherian, G; Krishnaswami, S; Sukumar, I P

1977-05-01

357

Progeria syndrome with cardiac complications.  

PubMed

A case report of 6-year-old boy with progeria syndrome, with marked cardiac complications is presented. The boy had cardiorespiratory failure. Discoloured purpuric skin patches, alopecia, prominent forehead, protuberant eyes, flattened nasal cartilage, malformed mandible, hypodentition, and deformed rigid fingers and toes were observed on examination. The boy was unable to speak. A sclerotic systolic murmur was audible over the mitral and aortic areas. Chest x-rays showed cardiac enlargement and the electrocardiogram (ECG) showed giant peaked P waves (right atrial hypertrophy) and right ventricular hypertrophy. Atherosclerotic dilated ascending aorta, thickened sclerotic aortic, mitral, and tricuspid valves with increased echo texture, left and right atrial and right ventricular dilatation, reduced left ventricular cavity, and thickened speckled atrial and ventricular septa were observed on echocardiography. PMID:24601202

Ilyas, Saadia; Ilyas, Hajira; Hameed, Abdul; Ilyas, Muhammad

2013-09-01

358

High resolution drift chambers  

SciTech Connect

High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

Va'vra, J.

1985-07-01

359

The Mobile Chamber  

NASA Technical Reports Server (NTRS)

A document discusses a simulation chamber that represents a shift from the thermal-vacuum chamber stereotype. This innovation, currently in development, combines the capabilities of space simulation chambers, the user-friendliness of modern-day electronics, and the modularity of plug-and-play computing. The Mobile Chamber is a customized test chamber that can be deployed with great ease, and is capable of bringing payloads at temperatures down to 20 K, in high vacuum, and with the desired metrology instruments integrated to the systems control. Flexure plans to lease Mobile Chambers, making them affordable for smaller budgets and available to a larger customer base. A key feature of this design will be an Apple iPad-like user interface that allows someone with minimal training to control the environment inside the chamber, and to simulate the required extreme environments. The feedback of thermal, pressure, and other measurements is delivered in a 3D CAD model of the chamber's payload and support hardware. This GUI will provide the user with a better understanding of the payload than any existing thermal-vacuum system.

Scharfstein, Gregory; Cox, Russell

2012-01-01

360

The Cloud Chamber  

NSDL National Science Digital Library

This web "booklet" from the University of Cambridge provides a description of the experiments of physicist Charles Thomson Rees Wilson that led to the first succesful cloud chamber, a powerful tool for nuclear and elementary particle physics. The site offers interactive graphics to help show how these chambers work. Photos and excerpts from some of Wilson's first publications are also included as well.

2008-09-23

361

Hypoplastic left heart syndrome in the fetus: Diagnostic features prior to birth and their impact on postnatal outcome  

Microsoft Academic Search

Hypoplastic left heart syndrome encompasses a diverse group of heart defects that share the common feature of underdevelopment of the left heart. There are multiple anatomic substrates involved in the development of hypoplastic left heart syndrome, as well as variants of classic hypoplastic left heart, that may signify unique risks and benefits. Additionally, other functional and anatomic cardiac findings as

Carlen A. Gomez-Fifer

2006-01-01

362

Cardiac sarcoidosis.  

PubMed

Cardiac sarcoidosis (CS) is a rare and under-recognized clinical entity that requires a high level of suspicion and low threshold for screening in order to make the diagnosis. CS may manifest in a variety of ways, and its initial presentation can range from asymptomatic electrocardiographic abnormalities to overt heart failure to sudden cardiac death. The aim of this literature review is to provide a comprehensive overview of CS, with an emphasis on clinical manifestations and special diagnostic and management considerations, while highlighting recent studies that have provided new insights into this unique disease. PMID:24969032

Zipse, Matthew M; Sauer, William H

2014-08-01

363

Treatment Related Cardiac Toxicity in Patients Treated for Breast Cancer.  

National Technical Information Service (NTIS)

To determine the incidence, dose/time-dependence, and functional significance of regional cardiac perfusion abnormalities in patients with left- sided breast cancer treated with radiation therapy (RT) with and without doxorubicin; 153 patients underwent p...

L. B. Marks

2005-01-01

364

Glycogenolysis and Phosphorylase Activity of Cardiac Muscle in Hemorrhagic Shock.  

National Technical Information Service (NTIS)

The concentration of metabolic substrates in cardiac muscle and in arterial and coronary venous blood was determined in control dogs and dogs in hemorrhagic shock. Levels of lactate, pyruvate, glycogen, and phosphorylase enzyme in left ventricular muscle ...

J. Doersching V. V. Glaviano

1966-01-01

365

Prediction of Mortality Risk by Different Methods of Indexation for Left Ventricular Mass  

Microsoft Academic Search

Objectives. We sought to compare the predictive value of echocardiographically determined left ventricular hypertrophy on death from all causes and cardiac mortality using various methods of indexation for left ventricular mass.Background. Considerable controversy exists regarding the optimal method for indexing left ventricular mass to body size in the clinical setting.Methods. The study included 988 consecutive patients who had both coronary

Youlian Liao; Richard S. Cooper; Ramon Durazo-Arvizu; George A. Mensah; Jalal K. Ghali

1997-01-01

366

Assessment of left ventricular systolic function in man from simultaneous echocardiographic and pressure measurements  

Microsoft Academic Search

Simultaneous measurements of left ventricular dimension and wall thickness by echocardiography, and of pressure by micromanometer, were made at cardiac catheterization in 30 patients with heart disease, in order to study mechanisms of impairment of left ventricular systolic function. Echocardiograms and pressure traces were digitized so that continuous measurements of left ventricular wall thickness and dimensions with their rates of

D G Gibson; D J Brown

1976-01-01

367

Congenital left ventricular diverticulum associated with congenital ileo-jejunal atresia.  

PubMed

Congenital left-ventricular diverticulum (CVD) is a rare cardiac malformation. Echocardiography, magnetic resonance imaging, multislice computed tomography, and left-ventricular angiography are diagnostic tools. In this case report, we present a 5-month-old infant with CVD associated with congenital ileal atresia. The diverticulum appears to be of the left-ventricular type. PMID:22576766

Binneto?lu, Fatih Köksal; Altun, Gürkan; Kaya, Ahmet; Babao?lu, Kadir

2012-10-01

368

Cardiac hydatid cyst: report of two cases.  

PubMed

Cardiac hydatid cyst is life threatening but rare. It is usually asymptomatic and has potentially lethal complications, so early diagnosis with definitive treatment is life-saving. In the present article, we report two cases. The first is a 30-year-old woman with a primary large multivesicular hydatid cyst in the left ventricle. The second is a 17-year-old woman who had multivisceral involvement with a cardiac hydatid cyst, a congenital cardiac anomaly that was an atrial septal defect complicated by pulmonary hypertension. 2-D echocardiography and magnetic resonance imaging confirmed the diagnosis. Surgical treatment was performed using extracorporeal circulation and adjunctive albendazol therapy. PMID:16352080

Ustünsoy, Ha?im; Akdemir, Ilyas; Sivrikoz, M Cumhur; Tahtaci, Nursan; Aksoy, Mehmet; Tunçözgür, Bülent

2002-01-01

369

Surgical treatment for hypoplastic left heart syndrome  

Microsoft Academic Search

Once considered a uniformly fatal condition, the outlook for newborns with hypoplastic left heart syndrome has been dramatically\\u000a improved with either a protocol of staged reconstruction or cardiac transplantation. Currently, a significant shortage of\\u000a suitable donor hearts restricts the applicability of transplantation for most newborns. At the University of Michigan, we\\u000a have adopted a policy of staged reconstruction for all

Edward L. Bove

1999-01-01

370

Hypertension, left ventricular hypertrophy, and sudden death  

Microsoft Academic Search

Left ventricular hypertrophy (LVH), a form of end-organ damage in hypertension, is associated with increased incidence of\\u000a sudden cardiac death (SCD). This review explores the possible mechanisms behind this phenomenon. SCD in LVH could be thrombotic\\/ischemic\\u000a or arrhythmic (eg, myocardial ischemia, even in the absence of significant coronary artery disease, may be one important factor).\\u000a Abnormalities of flow-mediated dilatation, endothelial

Lwin Lwin Tin; D. Gareth Beevers; Gregory Y. H. Lip

2002-01-01

371

Behavior of a Radial Time Projection Chamber  

NASA Astrophysics Data System (ADS)

Using Gas Electron Multiplying (GEM) foils for amplification, the detector allows for three-dimensional representations of particle tracks through two half cylinders filled with gas. Developed for the Bound Nucleon Structure (BONUS) experiment at Jefferson Lab, the RTPC allows experimenters to study the quark composition of the neutron by scattering electrons from deuterium nuclei. The defining feature of the detector is that it allows for a complete view of the interaction of the electron and target gas, including the protons left over after a reaction on the neutron. This experiment seeks to understand the efficiency of the detector and its amplification (signal strength for a given ionization, as a function of detector gas and high voltage), by making a measurement of the amount of energy deposited in the chamber per unit length from cosmic radiation. In order to test each half of the Radial Time Projection Chamber we use an 85% Helium and 15% Dimethyl Ether (85/15 HeDME) and an 80/20 HeDME at optimal voltages to detect cosmic particles. The detector takes an electronic snapshot of the incident particle by examining the charge deposited as a function of time. The importance of this technology should not be underestimated. Radial Time Projection Chambers could, in some applications, replace current Time Projection Chambers and Wire Chambers.

Bradshaw, Peter

2006-10-01

372

RF anechoic chamber test facilities  

Microsoft Academic Search

Radio frequency anechoic test chamber design is discussed. Radar absorbing materials are described. Electromagnetic compatibility testing in anechoic chambers is introduced. Special purpose chambers, e.g., for investigating a compact frequency range are considered.

B. F. Lawrence

1982-01-01

373

Computed tomography evaluation of cardiac structure and function.  

PubMed

Computed tomography is a noninvasive imaging modality that can be used for the evaluation of cardiac structure and function. This review provides an overview of established and emerging applications of cardiac computed tomography, including evaluation of left and right ventricular function, ventricular morphology, native and prosthetic valves, and pulmonary and coronary vein anatomy. PMID:24662335

Sala, Michiel L; Bizino, Maurice B; Amersfoort, Jacob; de Roos, Albert; Lamb, Hildo J

2014-05-01

374

Cardiac and hepatic seed implant embolization after prostate brachytherapy  

Microsoft Academic Search

Prostate brachytherapy seed implants occasionally embolize to lungs because of their small size. They may lodge in the right cardiac cavities before reaching the pulmonary arteries and lungs. A rare instance of seed migration to the coronary artery through an existing right-to-left cardiac shunt or patent foramen ovale has also been reported. I present a case of seed implant relocation

Ba D. Nguyen

2006-01-01

375

Gender Difference in the Risk Factors for Sudden Cardiac Death  

Microsoft Academic Search

Sudden cardiac death is most often caused by ventricular dysrhythmias. Although women have an incidence of sudden death lower than that of men, 34% of coronary deaths in women are sudden deaths. The atherogenic risk factors do not predict which women are at the highest risk of sudden cardiac death. Left ventricular hypertrophy is a strong risk factor for sudden

Seth T. Dahlberg

1990-01-01

376

Genome-wide expression patterns in physiological cardiac hypertrophy  

Microsoft Academic Search

BACKGROUND: Physiological left ventricular hypertrophy (LVH) involves complex cardiac remodeling that occurs as an adaptive response to chronic exercise. A stark clinical contrast exists between physiological LVH and pathological cardiac remodeling in response to diseases such as hypertension, but little is known about the precise molecular mechanisms driving physiological adaptation. RESULTS: In this study, the first large-scale analysis of publicly

Ignat Drozdov; Sophia Tsoka; Christos A Ouzounis; Ajay M Shah

2010-01-01

377

Contour extraction from cardiac MRI studies using snakes  

Microsoft Academic Search

The author investigated automatic extraction of left ventricular contours from cardiac magnetic resonance imaging (MRI) studies. The contour extraction algorithms were based on active contour models, or snakes. Based on cardiac MR image characteristics, the author suggested algorithms for extracting contours from these large data sets. The author specifically considered contour propagation methods to make the contours reliable enough despite

Surendra Ranganath

1995-01-01

378

Retrograde crystalloid cardioplegia preserves left ventricular systolic function better than antegrade cardioplegia in patients with occluded coronary arteries  

Microsoft Academic Search

Objective: To investigate retrograde and antegrade crystalloid cardioplegia in terms of cardiac cooling and postoperative cardiac function. Design: Prospective, randomized, and blinded. Setting: University hospital. Participants: Twenty male patients with triple-vessel disease and proximal occlusion of the circumflex or the left anterior descending coronary artery. Interventions: Left ventricular ejection fraction at rest and during exercise was evaluated by nuclear ventriculography

Jarl Ehrenberg; Mario Intonti; Anders Öwall; Lars-Åke Brodin; Torbjörn Ivert; Dan Lindblom

2000-01-01

379

Regional myocardial blood flow in patients with sick sinus syndrome randomized to long-term single chamber atrial or dual chamber pacing—effect of pacing mode and rate  

Microsoft Academic Search

OBJECTIVESThis study aimed to evaluate regional myocardial blood flow (MBF) and global left ventricular ejection fraction (LVEF) during chronic pacing in patients with sick sinus syndrome (SSS) randomized to either single chamber atrial (AAI) or dual chamber (DDD) pacing.BACKGROUNDExperimental studies indicate that chronic pacing in the right ventricular apex changes regional MBF, thereby compromising left ventricular function.METHODSThirty patients (age 74

Jens Cosedis Nielsen; Morten Bøttcher; Torsten Toftegaard Nielsen; Anders Kirstein Pedersen; Henning Rud Andersen

2000-01-01

380

Left atrium function assessment by echocardiography - physiological and clinical implications.  

PubMed

Left atrium enlargement is a pathophysiological response to volume and pressure overload associated with a wide range of cardiovascular disorders leading to left ventricle systolic and diastolic dysfunction. Physiological factors contribute to significant differences in left atrium size in normal individuals. Moreover, left atrium enlargement was shown to have a significant prognostic value for cardiovascular events such as heart failure, atrial fibrillation or stroke, and increased cardiovascular and all-cause mortality rates. Current imaging techniques such as two- and three dimensional echocardiography, cardiac magnetic resonance imaging and multi-detector computed tomography allow a detailed assessment of the left atrium. The current paper aims to offer an overview of two-dimensional echocardiography parameters which provide data concerning left atrium dimensions and phasic functions and may lead to a better understanding of left atrium physiology and pathology. PMID:24791847

Lupu, Silvia; Mitre, Adriana; Dobreanu, Dan

2014-06-01

381

The Mars Chamber  

NASA Video Gallery

The Mars chamber is a box about the size of a refrigerator that re-creates the temperatures, pressures, and atmosphere of the Martian surface, essentially creating a Mars environment on Earth! Scie...

382

Diagnostic approach to cardiac amyloidosis.  

PubMed

Amyloidosis is a relatively rare disease that may be underdiagnosed and could affect the entire human body. Many organs may be affected, which could increase the morbidity and mortality. Cardiac involvement is the leading cause of poor prognosis. Patients with cardiac amyloidosis are usually admitted with heart failure. The clinical presentation varies greatly, and using the correct approach is important in identifying cardiac amyloidosis. A 51-year-old man was diagnosed with chronic heart failure. He had increased brain natriuretic peptide levels, a low ejection fraction, and left and right ventricular hypertrophy with granular sparkling as seen by echocardiography. These findings led us to perform a cardiac biopsy that confirmed the diagnosis of cardiac amyloidosis. Further investigation revealed that the patient had amyloid light-chain type amyloidosis due to multiple myeloma. He is now undergoing the 3rd phase of chemotherapy. Congo-red stain is usually used by physicians to histologically confirm amyloidosis, with which apple-green birefringence indicates amyloid deposits. Other stains such as direct fast scarlet (DFS) and hematoxylin-eosin (HE) can also confirm the presence of amyloid deposits. In the present case, DFS and HE were used, both of which suggested amyloid deposits surrounding myocardial cells. The use of a combination of stains can increase the diagnostic sensitivity and specificity of amyloidosis. However, the typical echocardiographic appearances would be enough to diagnose cardiac amyloidosis when it is impossible for the patient to undergo a cardiac biopsy, if an additional histological specimen from another tissue such as abdominal fat confirms amyloidosis. PMID:25011639

Amin, Hilman Zulkifli; Mori, Shumpei; Sasaki, Naoto; Hirata, Kenichi

2014-01-01

383

Slurry-Mixing Chamber  

NASA Technical Reports Server (NTRS)

Paddles and water jets create uniform, continuous flow. Slurry-mixing chamber on hydrojet-jaw mining machine ensures uniform, continuously flowing slurry of coal particles in water. By mixing coal and water at high speed and keeping resulting slurry in constant motion, chamber prevents slurry from becoming dry semisolid that blocks flow. Also prevents coal particles from settling and caking in bends, corners, and other locations where flow changes in direction or speed.

Lewis, E. V.

1985-01-01

384

Cardiac Circulation  

NSDL National Science Digital Library

This simple FlashTM animation depicts blood flow through the great vessels and chambers of the mature heart. Clicking brings up labels. A second click brings up arrows defining venous flow. A third click brings up arrows tracing the arterial flow.

PhD Jack D Thatcher (West Virginia School of Osteopathic Medicine Structural Biology)

2009-11-20

385

Isolated congenital left ventricular diverticulum in an adult.  

PubMed

An isolated congenital left ventricular diverticulum, which is characterized by the local failure of the ventricular muscle during embryologic development, is a rare cardiac abnormality that may be found in isolated form or in the accompaniment of other cardiac abnormalities. Clinically, it has been reported to follow an asymptomatic course in the majority of cases; however, it may cause heart failure, arrhythmia, or chest pain in some patients. PMID:23190014

Bilgin, Murat; Yildiz, Serhat; Gul, Ilker; Nalbantgil, Sanem

2013-03-01

386

Growth hormone increases the proliferation of existing cardiac myocytes and the total number of cardiac myocytes in the rat heart  

Microsoft Academic Search

Objective: Growth hormone (GH) is known to induce growth of the normal rat heart. Whether this growth is due solely to hypertrophy of the cardiac myocytes or whether a concomitant hyperplasia of the cardiac myocytes also takes place is currently not known. Therefore, the aim of the present study was to investigate whether GH induces hyperplasia in the left ventricle

Annemarie Brüel; Tue E. H. Christoffersen; Jens R. Nyengaard

387

A randomized comparison ofatrial and dual-chamber pacing in177 consecutive patients with sick sinus syndrome  

Microsoft Academic Search

ObjectivesA randomized trial was done to compare single-chamber atrial (AAI) and dual-chamber (DDD) pacing in patients with sick sinus syndrome (SSS). Primary end points were changes in left atrial (LA) size and left ventricular (LV) size and function as measured by M-mode echocardiography.

Jens C Nielsen; Lene Kristensen; Henning R Andersen; Peter T Mortensen; Ole L Pedersen; Anders K Pedersen

2003-01-01

388

Sleeve reaction chamber system  

DOEpatents

A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

Northrup, M. Allen (Berkeley, CA); Beeman, Barton V. (San Mateo, CA); Benett, William J. (Livermore, CA); Hadley, Dean R. (Manteca, CA); Landre, Phoebe (Livermore, CA); Lehew, Stacy L. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA)

2009-08-25

389

Increase in cardiac myosin heavy-chain (MyHC) alpha protein isoform in hibernating ground squirrels, with echocardiographic visualization of ventricular wall hypertrophy and prolonged contraction.  

PubMed

Deep hibernators such as golden-mantled ground squirrels (Callospermophilus lateralis) have multiple challenges to cardiac function during low temperature torpor and subsequent arousals. As heart rates fall from over 300 beats min(-1) to less than 10, chamber dilation and reduced cardiac output could lead to congestive myopathy. We performed echocardiography on a cohort of individuals prior to and after several months of hibernation. The left ventricular chamber exhibited eccentric and concentric hypertrophy during hibernation and thus calculated ventricular mass was ~30% greater. Ventricular ejection fraction was mildly reduced during hibernation but stroke volumes were greater due to the eccentric hypertrophy and dramatically increased diastolic filling volumes. Globally, the systolic phase in hibernation was ~9.5 times longer, and the diastolic phase was 28× longer. Left atrial ejection generally was not observed during hibernation. Atrial ejection returned weakly during early arousal. Strain echocardiography assessed the velocity and total movement distance of contraction and relaxation for regional ventricular segments in active and early arousal states. Myocardial systolic strain during early arousal was significantly greater than the active state, indicating greater total contractile movement. This mirrored the increased ventricular ejection fraction noted with early arousal. However, strain rates were slower during early arousal than during the active period, particularly systolic strain, which was 33% of active, compared with the rate of diastolic strain, which was 67% of active. As heart rate rose during the arousal period, myocardial velocities and strain rates also increased; this was matched closely by cardiac output. Curiously, though heart rates were only 26% of active heart rates during early arousal, the cardiac output was nearly 40% of the active state, suggesting an efficient pumping system. We further analyzed proportions of cardiac myosin heavy-chain (MyHC) isoforms in a separate cohort of squirrels over 5 months, including time points before hibernation, during hibernation and just prior to emergence. Hibernating individuals were maintained in both a 4°C cold room and a 20°C warm room. Measured by SDS-PAGE, relative percentages of cardiac MyHC alpha were increased during hibernation, at both hibernacula temperatures. A potential increase in contractile speed, and power, from more abundant MyHC alpha may aid force generation at low temperature and at low heart rates. Unlike many models of cardiomyopathies where the alpha isoform is replaced by the beta isoform in order to reduce oxygen consumption, ground squirrels demonstrate a potential cardioprotective mechanism to maintain cardiac output during torpor. PMID:24072796

Nelson, O Lynne; Rourke, Bryan C

2013-12-15

390

Left atrial myxosarcoma with previously detected intestinal metastasis.  

PubMed

Primary cardiac myxosarcoma is a rare disease; it is exceedingly rare for symptoms of systemic metastasis to precede diagnosis of the primary cardiac tumor. We describe the case of a previously healthy 60-year-old man with left atrial myxosarcoma, who had first presented with jejunal intussusception due to intestinal polyposis. Three months after resection of the jejunum, the patient experienced cerebral infarction and pulmonary edema. Further physical evaluation, which included echocardiography for the 1st time, revealed a mass in the left atrium that protruded through the mitral valve into the left ventricle. At emergency cardiac surgery, we found that the tumor involved multiple sites of the left atrium, the pulmonary veins, and the mitral anterior leaflet. Two months after surgery, the patient died of massive cerebral hemorrhage. Necropsy disclosed multiple recurrences of the cardiac myxosarcoma and widespread metastatic lesions. The intestinal polyps that had been resected originally were diagnosed, on retrospective histopathologic examination, as metastases of the myxosarcoma. In this unusual case, the metastatic lesions were the 1st clinical manifestations of a malignant cardiac tumor. PMID:17420810

Takami, Yoshiyuki; Masumoto, Hiroshi; Terasawa, Akihiro; Kanai, Michio; Sugiura, Hiroshi

2007-01-01

391

A comparison between ranolazine and CVT-4325, a novel inhibitor of fatty acid oxidation, on cardiac metabolism and left ventricular function in rat isolated perfused heart during ischemia and reperfusion.  

PubMed

Inhibition of fatty acid oxidation has been reported to be cardioprotective against myocardial ischemic injury; however, recent studies have questioned whether the cardioprotection associated with putative fatty acid oxidation inhibitors, such as ranolazine and trimetazidine, are due to changes in substrate oxidation. Therefore, the goals of this study were to compare the effects of ranolazine with a new fatty acid oxidation inhibitor, CVT-4325 [(R)-1-(2-methylbenzo[d]thiazol-5-yloxy)-3-(4-((5-(4-(trifluoromethyl)phenyl)-1,2,4-oxadiazol-3-yl)methyl)-piperazin-1-yl)propan-2-ol], on carbohydrate and fatty acid oxidation and on left ventricular (LV) function in the response to ischemia/reperfusion in rat isolated perfused hearts. Metabolic fluxes were determined in hearts perfused in an isovolumic Langendorff mode using 13C nuclear magnetic resonance isotopomer analysis or in isolated working hearts using [14C]glucose and [3H]palmitate, with and without 10 microM ranolazine or 3 microM CVT-4325. Isovolumic perfused hearts were also subjected to 30 min of low-flow ischemia (0.3 ml/min) and 60 min of reperfusion, and working hearts were subjected to 15 min of zero-flow ischemia and 60 min of reperfusion. Regardless of the experimental protocol, ranolazine had no effect on carbohydrate or fatty acid oxidation, whereas CVT-4325 significantly reduced fatty acid oxidation up to approximately 7-fold with a concomitant increase in carbohydrate oxidation. At these same concentrations, although ranolazine significantly improved LV functional recovery following ischemia/reperfusion, CVT-4325 had no significant protective effect. These results demonstrate that at pharmacologically relevant concentrations, ischemic protection by ranolazine was not mediated by inhibition of fatty acid oxidation and conversely that inhibition of fatty acid oxidation with CVT-4325 was not associated with improved LV functional recovery. PMID:17202401

Wang, Peipei; Fraser, Heather; Lloyd, Steven G; McVeigh, Jeffrey J; Belardinelli, Luiz; Chatham, John C

2007-04-01

392

Assessment of left ventricular size and function during cardiac surgery. An intraoperative evaluation of six two-dimensional echocardiographic methods with real time three-dimensional echocardiography as a reference.  

PubMed

Transesophageal echocardiography is recommended to monitor left ventricular (LV) size and function in various operations. Generally, two-dimensional (2D) methods are applied intraoperatively. The aim of this study was to compare the accuracy and feasibility of 6 commonly used 2D methods to assess LV function during surgery. LV function in 120 consecutive patients was evaluated. Real time three-dimensional transesophageal echocardiograpy (3DTEE) served as reference. End-diastolic and end-systolic volumes and ejection fraction (EF) were analyzed with Simpson's method of discs (monoplane [MP] and biplane [BP]), eyeball method, Teichholz' method, and speckle tracking (ST) methods. Furthermore, fractional area change (FAC) and peak systolic pressure rise (dP/dt) were determined. Each 2D method was evaluated regarding correlation and agreement with 3DE, intra- and interobserver variability and the time required for evaluation. Simpson BP showed the strongest correlation and best agreement with 3DE for EF (limits of agreement 3.7 ± 11.6%) and volumes. Simpson MP showed similar agreement with 3DE compared to ST (2.8 ± 14.5% vs. 2.0 ± 15.3% and 3.8 ± 14.4% vs. 1.9 ± 15.6%, respectively). Both the eyeball method and Teichholz' method showed wide limits of agreement (-1.5 ± 18.2% and 5.2 ± 22.1%, respectively). DP/dt did not correlate with 3DE. FAC and ST FAC showed similar agreement. Application of 3DE (429 ± 108 seconds) took the longest time, and the eyeball method took the shortest time (8 ± 5 seconds) for analysis. Simpson BP is the most accurate intraoperative 2D method to evaluate LV function, followed by long-axis MP evaluations. Short-axis views were less accurate but may be suited for monitoring. We do not recommend using dP/dt. PMID:23405969

Grossgasteiger, Manuel; Hien, Maximilian D; Graser, Bastian; Rauch, Helmut; Gondan, Matthias; Motsch, Johann; Rosendal, Christian

2013-07-01

393

Percent Emphysema, Airflow Obstruction, and Impaired Left Ventricular Filling  

PubMed Central

BACKGROUND Very severe chronic obstructive pulmonary disease causes cor pulmonale with elevated pulmonary vascular resistance and secondary reductions in left ventricular filling, stroke volume, and cardiac output. We hypothesized that emphysema, as detected on computed tomography (CT), and airflow obstruction are inversely related to left ventricular end-diastolic volume, stroke volume, and cardiac output among persons without very severe lung disease. METHODS We measured left ventricular structure and function with the use of magnetic resonance imaging in 2816 persons who were 45 to 84 years of age. The extent of emphysema (expressed as percent emphysema) was defined as the percentage of voxels below ?910 Houns