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1

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

2

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

3

[Cardiac resynchronization through a persistent left superior vena cava].  

PubMed

Cardiac resynchronization therapy is effective in the treatment of patients with severe heart failure and intraventricular dysynchrony. However, we are sometimes faced with the unexpected presence of a persistent left superior vena cava. We report the case of a patient with dilated cardiomyopathy and left ventricular dysynchrony in which we implanted a resynchronization pacemaker exclusively through a persistent left superior vena cava that did not communicate with the right vena cava. PMID:17194405

Moriña-Vázquez, P; Barba-Pichardo, R; Venegas Gamero, J; Herrera Carranza, M

2006-12-01

4

Sympathetic stimulation alters left ventricular relaxation and chamber size.  

PubMed

Alterations in left ventricular (LV) contractility, relaxation, and chamber dimensions induced by efferent sympathetic nerve stimulation were investigated in nine anesthetized open-chest dogs in sinus rhythm. Supramaximal stimulation of acutely decentralized left stellate ganglia augmented heart rate, LV systolic pressure, and rate of LV pressure rise (maximum +dP/dt, 1,809 +/- 191 to 6,304 +/- 725 mmHg/s) and fall (maximum -dP/dt, -2,392 +/- 230 to -4,458 +/- 482 mmHg/s). It also reduced the time constant of isovolumic relaxation, tau (36.5 +/- 4.8 to 14.9 +/- 1.1 ms). Simultaneous two-dimensional echocardiography recorded reductions in end-diastolic and end-systolic LV cross-sectional chamber areas (23 and 31%, respectively), an increase in area ejection fraction (32%), and increases in end-diastolic and end-systolic wall thicknesses (14 and 13%, respectively). End-systolic and end-diastolic wall stresses were unchanged by stellate ganglion stimulation (98 +/- 12 to 95 +/- 9 dyn x 10(3)/cm2; 6.4 +/- 2.4 to 2.4 +/- 0.3 dyn x 10(3)/cm2, respectively). Atrial pacing to similar heart rates did not alter monitored indexes of contractility. Dobutamine and isoproterenol induced changes similar to those resulting from sympathetic neuronal stimulation. These data indicate that when the efferent sympathetic nervous system increases left ventricular contractility and relaxation, concomitant reductions in systolic and diastolic dimensions of that chamber occur that are associated with increasing wall thickness such that LV wall stress changes are minimized. PMID:8430868

Burwash, I G; Morgan, D E; Koilpillai, C J; Blackmore, G L; Johnstone, D E; Armour, J A

1993-01-01

5

Infective Left Atrial Dissecting Flap after Cardiac Surgery  

PubMed Central

Left atrial dissection (LatD), defined as the forced separation of the left atrial (LA) wall layers by blood, is a rare and severe complication of cardiac surgery. It is most frequently associated with atrioventricular junction injuries. We report a case of infected LatD after coronary artery bypass graft, mitral valve replacement, aortic valve replacement and ascending aortic root replacement. The patient was presented with septicemia and disseminated intravascular coagulation. To the best of our knowledge, this is the first case report of LA dissecting flap concomitant with attached infective vegetations identified by transesophageal echocardiography. PMID:25309695

Tabiban, Sasan; Ghaemian, Ali; Bagheri, Babak; Shokri, Mojtaba

2014-01-01

6

Shape and dimensions of cardiac chambers: Importance of CT section thickness and orientation. [Dogs  

Microsoft Academic Search

Three-dimensional (3D) computed tomography (CT) scan data were used to quantitate the geometry of all heart chambers. The Dynamic Spatial Reconstructor (DSR) was used to scan dogs with in situ casts of the cardiac chambers. Chamber volumes estimated from DSR images were accurate within 5% of water displacement volume measurements of the actual casts for chambers greater than 11 ml

E. A. Hoffman; E. L. Ritman

1985-01-01

7

Thrombi in all four cardiac chambers in a patient with an old anteroseptal myocardial infarction and atrial flutter.  

PubMed

Cases with thrombi in multiple cardiac chambers are rare. We report an extremely rare case in which thrombi were formed in all four cardiac chambers at the same time. A 55-year-old man presented with biventricular failure and liver dysfunction. A 12-lead ECG and an echocardiogram revealed an old anteroseptal myocardial infarction with aneurysm formation and atrial flutter. A transesophageal echocardiogram and a CT of the chest revealed thrombi in the right and left atrial appendage, right ventricular apex and left ventricular aneurysm. Pulmonary emboli were also identified. Stasis of the blood due to ventricular dysfunction and atrial flutter was considered to be responsible. The patient died of multiorgan failure due to circulatory failure. PMID:25422354

Ida, Hanae; Hirata, Kazuhito; Takahashi, Takanori; Hirosawa, Takanobu

2014-01-01

8

A novel cardiac MR chamber volume model for mechanical dyssynchrony assessment  

NASA Astrophysics Data System (ADS)

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

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

2009-02-01

9

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. PMID:24988467

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

2014-01-01

10

Current cardiac imaging techniques for detection of left ventricular mass  

PubMed Central

Estimation of left ventricular (LV) mass has both prognostic and therapeutic value independent of traditional risk factors. Unfortunately, LV mass evaluation has been underestimated in clinical practice. Assessment of LV mass can be performed by a number of imaging modalities. Despite inherent limitations, conventional echocardiography has fundamentally been established as most widely used diagnostic tool. 3-dimensional echocardiography (3DE) is now feasible, fast and accurate for LV mass evaluation. 3DE is also superior to conventional echocardiography in terms of LV mass assessment, especially in patients with abnormal LV geometry. Cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) are currently performed for LV mass assessment and also do not depend on cardiac geometry and display 3-dimensional data, as well. Therefore, CMR is being increasingly employed and is at the present standard of reference in the clinical setting. Although each method demonstrates advantages over another, there are also disadvantages to receive attention. Diagnostic accuracy of methods will also be increased with the introduction of more advanced systems. It is also likely that in the coming years new and more accurate diagnostic tests will become available. In particular, CMR and CCT have been intersecting hot topic between cardiology and radiology clinics. Thus, good communication and collaboration between two specialties is required for selection of an appropriate test. PMID:20515461

2010-01-01

11

Image-Guided Radiotherapy for Cardiac Sparing in Patients with Left-Sided Breast Cancer  

PubMed Central

Patients with left-sided breast cancer are at risk of cardiac toxicity because of cardiac irradiation during radiotherapy with the conventional 3-dimensional conformal radiotherapy technique. In addition, many patients may receive chemotherapy prior to radiation, which may damage the myocardium and may increase the potential for late cardiac complications. New radiotherapy techniques such as intensity-modulated radiotherapy (IMRT) may decrease the risk of cardiac toxicity because of the steep dose gradient limiting the volume of the heart irradiated to a high dose. Image-guided radiotherapy (IGRT) is a new technique of IMRT delivery with daily imaging, which may further reduce excessive cardiac irradiation. Preliminary results of IGRT for cardiac sparing in patients with left-sided breast cancer are promising and need to be investigated in future prospective clinical studies. PMID:25295227

Lemanski, Claire; Thariat, Juliette; Ampil, Federico L.; Bose, Satya; Vock, Jacqueline; Davis, Rick; Chi, Alexander; Dutta, Suresh; Woods, William; Desai, Anand; Godinez, Juan; Karlsson, Ulf; Mills, Melissa; Nguyen, Nam Phong; Vinh-Hung, Vincent

2014-01-01

12

Recurrence of nonfamilial cardiac myxoma in the left ventricle: A case report.  

PubMed

A left atrial myxoma was found and removed in a 47-year-old woman admitted for acute ischemic cerebrovascular disease, without family history of cardiac tumor. Follow-up echocardiography, 15 months later, demonstrated a new myxoma in the left ventricle. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 42:576-577, 2014. PMID:24797084

Song, Xiaole; Tang, Li; Yang, Jun; Li, Nan

2014-11-12

13

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. PMID:24749115

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

2013-01-01

14

Primary cardiac sarcoma presenting as acute left-sided heart failure  

PubMed Central

Primary cardiac sarcomas are rare malignant tumors of the heart. Clinical features depend on the site of tumor and vary from symptoms of congestive heart failure to thromboembolism and arrhythmias. Echocardiography is helpful but definitive diagnosis is established by histopathology. Surgical resection is the mainstay of treatment, and the role of chemotherapy and radiotherapy is unclear. We report a case of primary cardiac sarcoma which presented with signs and symptoms of acute left-sided heart failure. PMID:25147639

Pathak, Ranjan; Nepal, Santosh; Giri, Smith; Ghimire, Sushil; Aryal, Madan Raj

2014-01-01

15

Relation Between Cardiac Sympathetic Activity and Hypertensive Left Ventricular Hypertrophy  

Microsoft Academic Search

Background—Left ventricular (LV) hypertrophy is an independent risk factor for cardiovascular morbidity and mortality in hypertensive subjects. Sympathetic activation has been suggested to contribute to LV hypertrophy, but this has not yet been conclusively validated in humans. Methods and Results—We comprehensively assessed total systemic and regional sympathetic activity by radiotracer dilution methods and microneurography in 15 untreated hypertensive subjects with

Markus P. Schlaich; David M. Kaye; Elisabeth Lambert; Marcus Sommerville; Flora Socratous; Murray D. Esler

2010-01-01

16

[Selection of protection regimen of dual-chamber cardiac pacing against paroxysmal supraventricular tachycardia].  

PubMed

Criteria of selection of a type of protection against paroxysmal supraventricular tachycardia were studied in 38 patients with permanent dual-chamber cardiac pacing. Three types of protection were distinguished. Criteria for their selection were presence of "pacemaker syndrome", state of chronotropic function of the heart, frequency of attacks of supraventricular tachycardia, results of modeling of pathological atrial activity. During follow-up after programming of optimal type of protection of dual-chamber pacing (mean duration 5.1 years) chronic supraventricular tachycardia developed in 13.5% of patients, survival was 89.2%. PMID:12891250

Cherkasov, V A; Protopopov, V V; Molodykh, S V

2003-01-01

17

Effects of Injectable Anesthetic Combinations on Left Ventricular Function and Cardiac Morphology in Sprague-Dawley Rats  

PubMed Central

Novel anesthetic agents or combinations may provide superior general anesthesia for echocardiography in rodents with the potential for reduced adverse effects. This study sought to characterize the effects of 3 injectable anesthetics on left ventricular (LV) systolic function and cardiac morphology in healthy male and female rats. Rats underwent echocardiographic assessment after general anesthesia via pentobarbital or combinations of ketamine and medetomidine (KME) and ketamine and midazolam (KMI) according to a crossover Latin-square design. Blood samples for serum estradiol measurements were obtained from all females after echocardiography with each anesthetic. Rats given KMI showed superior LV systolic function with the highest values for fractional shortening (FS), ejection fraction (EF) and stroke volume, whereas heart rate was greatest with pentobarbital, followed by KMI and then KME. KME produced the greatest effects on cardiac morphology, most notably during systole, including reduced septal and posterior wall thickness and increased LV chamber dimensions and volumes. In addition, KME had the greatest cardiac-depressing effects on LV systolic function, including reduced FS, EF, and heart rate values. Compared with male rats, female rats had superior LV function with greater EF and FS values, whereas male rats showed higher heart rate. Significant negative correlations were noted between serum estradiol levels and FS and EF values in female rats receiving KME. We conclude that the combination of KMI may be a superior anesthetic for use in male and female rats undergoing echocardiography. PMID:23562031

Sabatini, Carla F; O'Sullivan, M Lynne; Valcour, James E; Sears, William; Johnson, Ron J

2013-01-01

18

Cardiac transplant outcome of patients supported on left ventricular assist device vs intravenous inotropic therapy  

Microsoft Academic Search

BackgroundAlthough the left ventricular assist device (LVAD) has been increasingly used as a bridge to transplant, its effect on post-transplant outcome is uncertain. We, therefore, designed this study using the Cardiac Transplant Research Database to compare patients supported on an LVAD before transplant with those treated with intravenous inotropic medical therapy.

Brian E Jaski; Joseph C Kim; David C Naftel; John Jarcho; Maria Rosa Costanzo; Howard J Eisen; James K Kirklin; Robert C Bourge

2001-01-01

19

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

20

Left-Right Asymmetry and Cardiac Looping: Implications for Cardiac Development and Congenital Heart Disease  

Microsoft Academic Search

Proper morphogenesis and positioning of internal organs requires delivery and interpretation of precise signals along the anterior-posterior, dorsal-ventral, and left-right axes. An elegant signaling cascade determines left- versus right- sided identity in visceral organs in a concordant fashion, resulting in a predictable left-right (LR) organ asymmetry in all vertebrates. The complex morphogenesis of the heart and its connections to the

IRFAN S. KATHIRIYA; DEEPAK SRIVASTAVA

2001-01-01

21

Turning crocodilian hearts into bird hearts: growth rates are similar for alligators with and without right-to-left cardiac shunt  

PubMed Central

The functional and possible adaptive significance of non-avian reptiles' dual aortic arch system and the ability of all non-avian reptiles to perform central vascular cardiac shunts have been of great interest to comparative physiologists. The unique cardiac anatomy of crocodilians – a four-chambered heart with the dual aortic arch system – allows for only right-to-left (R–L; pulmonary bypass) cardiac shunt and for surgical elimination of this shunt. Surgical removal of the R–L shunt, by occluding the left aorta (LAo) upstream and downstream of the foramen of Panizza, results in a crocodilian with an obligatory, avian/mammalian central circulation. In this study, R–L cardiac shunt was eliminated in age-matched, female American alligators (Alligator mississippiensis; 5–7 months of age). We tested the hypothesis that surgical elimination of R–L cardiac shunt would impair growth (a readily measured proxy for fitness) compared with sham-operated, age-matched controls, especially in animals subjected to exhaustive exercise. While regular exercise caused a decrease in size (snout-to-vent length, head length and body mass), elimination of the capacity for R–L cardiac shunt did not greatly reduce animal growth, despite a chronic ventricular enlargement in surgically altered juvenile alligators. We speculate that, despite being slightly smaller, alligators with an occluded LAo would have reached sexual maturity in the same breeding season as control alligators. This study suggests that crocodilian R–L cardiac shunt does not provide an adaptive advantage for juvenile alligator growth and supports the logic that cardiac shunts persist in crocodilians because they have not been selected against. PMID:20639429

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

2010-01-01

22

Role of cardiac CTA in estimating left ventricular volumes and ejection fraction  

PubMed Central

Left ventricular ejection fraction (LVEF) is an important predictor of cardiac outcome and helps in making important diagnostic and therapeutic decisions such as the treatment of different types of congestive heart failure or implantation of devices like cardiac resynchronization therapy-defibrillator. LVEF can be measured by various techniques such as transthoracic echocardiography, contrast ventriculography, radionuclide techniques, cardiac magnetic resonance imaging and cardiac computed tomographic angiography (CTA). The development of cardiac CTA using multi-detector row CT (MDCT) has seen a very rapid improvement in the technology for identifying coronary artery stenosis and coronary artery disease in the last decade. During the acquisition, processing and analysis of data to study coronary anatomy, MDCT provides a unique opportunity to measure left ventricular volumes and LVEF simultaneously with the same data set without the need for additional contrast or radiation exposure. The development of semi-automated and automated software to measure LVEF has now added uniformity, efficiency and reproducibility of practical value in clinical practice rather than just being a research tool. This article will address the feasibility, the accuracy and the limitations of MDCT in measuring LVEF. PMID:25276310

Singh, Robin Man; Singh, Balkrishna Man; Mehta, Jawahar Lal

2014-01-01

23

Role of cardiac CTA in estimating left ventricular volumes and ejection fraction.  

PubMed

Left ventricular ejection fraction (LVEF) is an important predictor of cardiac outcome and helps in making important diagnostic and therapeutic decisions such as the treatment of different types of congestive heart failure or implantation of devices like cardiac resynchronization therapy-defibrillator. LVEF can be measured by various techniques such as transthoracic echocardiography, contrast ventriculography, radionuclide techniques, cardiac magnetic resonance imaging and cardiac computed tomographic angiography (CTA). The development of cardiac CTA using multi-detector row CT (MDCT) has seen a very rapid improvement in the technology for identifying coronary artery stenosis and coronary artery disease in the last decade. During the acquisition, processing and analysis of data to study coronary anatomy, MDCT provides a unique opportunity to measure left ventricular volumes and LVEF simultaneously with the same data set without the need for additional contrast or radiation exposure. The development of semi-automated and automated software to measure LVEF has now added uniformity, efficiency and reproducibility of practical value in clinical practice rather than just being a research tool. This article will address the feasibility, the accuracy and the limitations of MDCT in measuring LVEF. PMID:25276310

Singh, Robin Man; Singh, Balkrishna Man; Mehta, Jawahar Lal

2014-09-28

24

Computer-aided scheme for functional index computation of left ventricle in cardiac CTA: segmentation and partitioning of left ventricle  

NASA Astrophysics Data System (ADS)

Cardiac functional indices, such as ejection fraction and regional wall motion/ thickening, are commonly used for assessing the contractility and functionality of the heart in clinical practice. An important step for computer-aided determination of functional indices is the automated segmentation of the heart from computed tomography angiography (CTA) and the partitioning of the left ventricle into 16 segments. We develop a fully automatic scheme which not only segments the whole heart from cardiac CTA images, but also partitions the left ventricle, including the blood pool and myocardium, into 16 segments of bull's eye plot. The segmentation is based on image registration and atlas propagation techniques, whereas the bull's eye plot is first obtained through atlas propagation and then further improved to correct inconsistency across different subjects, uneven size for each segment and "zig-zag" edges between them. In this preliminary study, a cohort of ten clinical CTA data was employed to compute and evaluate the regional functional indices as well as the global indices.

Huang, Hui; Zhuang, Xiahai; Shao, Yi; Lan, Tian; Liu, Liu; Li, Qiang

2013-02-01

25

Prognostic Value of Left Ventricular Diastolic Dysfunction in Patients Undergoing Cardiac Catheterization for Coronary Artery Disease  

PubMed Central

We hypothesized that left ventricular (LV) diastolic dysfunction assessed by cardiac catheterization may be associated with increased risk for cardiovascular events. To test the hypothesis, we assessed diastolic function by cardiac catheterization (relaxation time constant (Tau) and end-diastolic pressure (EDP)) as well as Doppler echocardiography (early diastolic mitral annular velocity (e?) and a ratio of early diastolic mitral inflow to annular velocities (E/e?)) in 222 consecutive patients undergoing cardiac catheterization for coronary artery disease (CAD). During a followup of 1364 ± 628 days, 5 cardiac deaths and 20 unscheduled cardiovascular hospitalizations were observed. Among LV diastolic function indices, Tau > 48?ms and e? < 5.8?cm/s were each significantly associated with lower rate of survival free of cardiovascular hospitalization. Even after adjustment for potential confounders (traditional cardiovascular risk factors, the severity of CAD, and cardiovascular medications), the predictive value of Tau > 48?ms and e? < 5.8?cm/s remained significant. No predictive value was observed in EDP, E/e?, or LV ejection fraction. In conclusion, LV diastolic dysfunction, particularly impaired LV relaxation assessed by both cardiac catheterization and Doppler echocardiography, is independently associated with increased risk for cardiac death or cardiovascular hospitalization in patients with known or suspected CAD. PMID:22567531

Fukuta, Hidekatsu; Ohte, Nobuyuki; Wakami, Kazuaki; Goto, Toshihiko; Tani, Tomomitsu; Kimura, Genjiro

2012-01-01

26

Cardiac arrest due to aberrant left coronary artery originating from the right sinus of valsalva in a young girl  

Microsoft Academic Search

We report a 14-year-old girl who sustained a syncope followed by cardiac arrest. She was kept alive for three days by full cardiocirculatory support using left and right ventricular assist devices, but subsequently died in multiple organ failure. Autopsy revealed an anomalous origin of the left coronary artery (LCA) from the right sinus of Valsalva (RSV) and a major left

J. H. Vander Sande; M. F. Vandermast; B. J. Amsel; P. A. Verrelst; P. J. Walter; L. L. Bossaert

1989-01-01

27

Clinical comparison of acute single to dual chamber pacing in chronotropically incompetent patients with left ventricular dysfunction.  

PubMed

Dual chamber, rate responsive (DDDR) pacing is felt to be superior to ventricular, rate responsive (VVIR) pacing since it more closely mimics the normal electrical and hemodynamic activity of the heart. This reasoning has been used to justify the higher initial costs and increased complexity of dual chamber system. This study was designed to determine if objective criteria could be identified during acute testing justify implanting a dual chamber instead of a single chamber system in patients with left ventricular dysfunction. Eight patients with DDDR pacemakers (implanted for chronotropic incompetence) and left ventricular dysfunction underwent exercise radionuclide angiography and graded exercise treadmill testing. Each patient performed the tests in the single (VVIR) and dual (DDDR) chamber modes in a randomized, blinded fashion. We found that objective parameters such as ejection fraction (31% +/- 13% vs 31% +/- 10%), exercise tolerance (6.1 +/- 2.7 min vs 6.3 +/- 2.9 min), oxygen consumption (VO2) (941 +/- 286 mL/min vs 994 +/- 314 mL/min), carbon dioxide production (VCO2) (995 +/- 332 mL/min vs 1054 +/- 356 mL/min), and maximum attainable workload (43 +/- 24 W vs 46 +/- 22 W) did not differ between the single and dual chamber pacing modes. These findings suggest that in the acute setting, the additional cost and complexity of dual chamber, rate responsive pacing cannot be justified by objective improvements in exercise tolerance in patients with underlying left ventricular dysfunction. PMID:7770363

Barrington, W W; Windle, J R; Easley, A A; Rundlett, R; Eisenger, G

1995-03-01

28

Utility of cardiac MRI in guiding revascularization therapy in unprotected left main stenosis: a case report.  

PubMed

Decision to select unprotected left main (ULM) stenting versus coronary artery bypass grafting surgery (CABG) depends on a multiplicity of factors, one of the most critical of which is myocardial viability. Delayed enhancement cardiac magnetic resonance (CMR) imaging has emerged as a useful means of comprehensively evaluating viable myocardium in postmyocardial infarct patients who require further revascularization. We present a patient with ULM stenosis in whom CMR imaging assisted in the decision to perform percutaneous coronary intervention over CABG. PMID:17765652

Suh, William M; Fowler, Steven J; Wallis, James B; Kern, Morton J; Ahsan, Chowdhury H

2007-01-01

29

Left-ventricular heart aneurism as a new source of resident cardiac stem cells  

Microsoft Academic Search

In the past few years, it has been established that the heart contains a reservoir of stem and progenitor cells. These cells\\u000a are able to differentiate in cardiomyogenic, endothelial, and smooth muscle lineages in vitro and in vivo and, following injection\\u000a into an infarcted myocardium, these cells prevent the remodeling of the left ventricle and improve cardiac function. The aim

K. V. Dergilev; K. A. Rubina; Z. I. Tsokolaeva; V. Yu. Sysoeva; A. I. Gmyzina; N. I. Kalinina; T. M. Belyavskaya; R. S. Akchurin; E. V. Parfenova; V. A. Tkachuk

2010-01-01

30

Impact of weightlessness on cardiac shape and left ventricular stress/strain distributions.  

PubMed

In this paper, a finite element model of the heart is developed to investigate the impact of different gravitational loadings of Earth, Mars, Moon, and microgravity on the cardiac shape and strain/stress distributions in the left ventricle. The finite element model is based on realistic 3D heart geometry, detailed fiber/sheet micro-architecture, and a validated orthotropic cardiac tissue model and constitutive relationship that capture the passive behavior of the heart at end-diastole. The model predicts the trend and magnitude of cardiac shape change at different gravitational levels with great fidelity in comparison to recent cardiac sphericity measurements performed during simulated reduced-gravity parabolic flight experiments. Moreover, the numerical predictions indicate that although the left ventricular strain distributions remain relatively unaltered across the gravitational fields and the strain extrema values occur at the same relative locations, their values change noticeably with decreasing gravity. As for the stress, however, both the magnitude and location of the extrema change with a decrease in the gravitational field. Consequently, tension regions of the heart on Earth can change into compression regions in space. PMID:24048335

Iskovitz, Ilana; Kassemi, Mohammad; Thomas, James D

2013-12-01

31

Radionuclide assessment of left ventricular diastolic filling in diabetes mellitus with and without cardiac autonomic neuropathy.  

PubMed

Indexes of left ventricular diastolic filling were measured by radionuclide ventriculography in 28 patients with insulin-dependent diabetes mellitus without evidence of ischemic heart disease. Six patients (21%) had abnormal diastolic filling and differed from diabetic patients with normal filling in their greater severity of cardiac autonomic neuropathy, assessed by noninvasive means, and their lower plasma norepinephrine levels in the supine (131.1 +/- 24.7 versus 356.2 +/- 58.4 pg/ml, p less than 0.01) and upright (224.9 +/- 47.8 versus 673.3 +/- 122.3 pg/ml, p less than 0.005) positions. The diabetic patients determined as having cardiac autonomic neuropathy (n = 15) had depressed left ventricular diastolic filling compared with subjects free of autonomic neuropathy, whether measured as the time to peak filling rate (154.2 +/- 12.0 versus 119.1 +/- 10.6 ms, p less than 0.05) or the time to peak filling rate normalized to the cardiac cycle length (24.3 +/- 2.2 versus 16.2 +/- 1.5%, p less than 0.01). Of the various tests of autonomic nervous system function, the strongest correlate of impaired diastolic filling was orthostasis, measured as the decrease in systolic blood pressure with standing (r = 0.584, p less than 0.001). Thus, in patients with diabetes mellitus, alterations in sympathetic nervous system activity are associated with abnormalities of left ventricular diastolic filling. PMID:3011872

Kahn, J K; Zola, B; Juni, J E; Vinik, A I

1986-06-01

32

A look at the upper heart chamber: the left atrium in chronic kidney disease.  

PubMed

Altered left ventricular (LV) mass and function are classical hallmarks of cardiomyopathy in chronic kidney disease (CKD). The left atrium (LA), a heart chamber exquisitely sensitive to volume overload and diastolic function, is an independent predictor of death and adverse cardiovascular (CV) events in high-risk patients such as those with hypertension and/or with heart failure. In this review we focus on the relationship of LA size with LV diastolic function, and the association between LA enlargement and CV and renal outcomes in patients with CKD, including patients with end-stage renal disease. Increased LA size emerges as a powerful predictor of mortality and major adverse CV events in both end-stage and early CKD, and some studies also show a close association between enlarged LA and renal disease progression. Secondary analyses of clinical trials suggest that the LA has the potential to be elected as a surrogate end point in CKD patients but the issue remains to be tested in specifically designed clinical studies. PMID:24286975

Paoletti, Ernesto; Zoccali, Carmine

2014-10-01

33

The inverse exponential relationship between cardiac mortality and radionuclide left ventricular ejection fraction  

SciTech Connect

Left ventricular ejection fraction (LVEF) is a known predictor of cardiac death, and may be readily measured with radionuclide ventriculography (RVG). However the quantitative nature of the relationship of LVEF to cardiac death is not agreed. Therefore the authors prospectively followed survival in 592 consecutive adults with confirmed cardiac disease, but no other life limiting illness, in whom LVEF was measured with radionuclide ventriculography >1 year ago. The diagnosis was coronary disease (88%), cardiomyopathy (6%) or valvular disease (6%). Mean age was 56 years (range 30-81); 81% were male. Cardiac mortality/month % (CM/Mo%) was higher (P<0.001) in the 1st 2 months (Mo 1-2) than later, but did not change from the 3rd to 36th month (Mo 3-36). The relationship between CM/Mo% and LVEF is log-linear (inverse exponential). Therefore studies which dichotomise LVEF levels above or below an arbitrary value, or assume a linear relationship between cardiac mortality and LVEF, may overestimate the independent prognostic value of other variables relative to LVEF determined by RVG.

Kelly, M.J.; Kalff, V.; Pitt, A.

1985-05-01

34

Effects of ventricular insertion sites on rotational motion of left ventricular segments studied by cardiac MR  

PubMed Central

Objective: Obtaining new details for rotational motion of left ventricular (LV) segments using velocity encoding cardiac MR and correlating the regional motion patterns to LV insertion sites. Methods: Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Peak rotational velocities and circumferential velocity curves were obtained for 16 ventricular segments. Results: Reduced peak clockwise velocities of anteroseptal segments (i.e. Segments 2 and 8) and peak counterclockwise velocities of inferoseptal segments (i.e. Segments 3 and 9) were the most prominent findings. The observations can be attributed to the LV insertion sites into the right ventricle, limiting the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments as viewed from the apex. Relatively lower clockwise velocities of Segment 5 and counterclockwise velocities of Segment 6 were also noted, suggesting a cardiac fixation point between these two segments, which is in close proximity to the lateral LV wall. Conclusion: Apart from showing different rotational patterns of LV base, mid ventricle and apex, the study showed significant differences in the rotational velocities of individual LV segments. Correlating regional wall motion with known orientation of myocardial aggregates has also provided new insights into the mechanisms of LV rotational motions during a cardiac cycle. Advances in knowledge: LV insertion into the right ventricle limits the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments adjacent to the ventricular insertion sites. The pattern should be differentiated from wall motion abnormalities in cardiac pathology. PMID:24133098

Robson, M D; Rider, O J; Pegg, T J; Dasanu, C A; Jung, B A; Clarke, K; Holloway, C J

2013-01-01

35

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

36

Left main coronary artery atresia and associated cardiac defects: report on concomitant surgical treatment.  

PubMed

A 9-year-old boy with congenital atresia of the left main coronary artery underwent myocardial revascularization. Coarctation of the aorta and ventricular septal defect were diagnosed at the age of 1 year. At age 7 years, the child presented with syncope while exercising. Preoperative evaluation included cardiac catheterization which revealed the unexpected finding of congenital atresia of the left main coronary artery with origin of the circumflex artery from the right coronary artery. Surgical correction included myocardial revascularization by means of left internal mammary artery graft to the anterior descending coronary artery, coarctation resection, and ventricular septal defect repair. The patient recovered uneventfully. We report the details of this extremely rare case with successful concomitant surgical management of the congenital coronary artery anomaly and the associated structural heart disease. PMID:23804483

Jatene, Marcelo; Juaneda, Ignacio; Miranda, Rogerio Dos Anjos; Gato, Rafaella; Marcial, Miguel Lorenzo Barbero

2011-10-01

37

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

38

Electrical storm: Role of stellate ganglion blockade and anesthetic implications of left cardiac sympathetic denervation  

PubMed Central

An electrical storm is usually associated with catecholaminergic surge following myocardial ischaemia and manifest as recurrent ventricular arrhythmias, requiring frequent DC shocks. Delivering repeated DC shocks induces myocardial damage and further worsens the arrhythmias, which are resistant to the antiarrhythmic drugs. Cardiac sympathetic blockade abates the excessive catecholaminergic drive and help pacifying the malignant ventricular arrhythmias. We treated the electrical storm in a 52-year-old male with ultrasound-guided left sympathetic ganglion block followed by surgical left cardiac sympathetic denervation. The patient remained symptom-free without any incident of ventricular arrhythmias for 8 months after the surgery. The ultrasonography during blockade of the stellate ganglion enhances the success rate of the technique, reduces the quantity of local anaesthetic required to produce desired effects and prevents technical complications. Supraclavicular surgical access to the upper thoracic sympathetic chain obviates the necessity for one lung ventilation and lateral decubitus during surgery, when the patient is in hemodynamically unstable condition. Sympathectomy can be performed under general anaesthesia taking cautions to avoid sympathetic stimulation in intraoperative period. PMID:24163457

Gadhinglajkar, Shrinivas; Sreedhar, Rupa; Unnikrishnan, M.; Namboodiri, Narayanan

2013-01-01

39

Electrical storm: Role of stellate ganglion blockade and anesthetic implications of left cardiac sympathetic denervation.  

PubMed

An electrical storm is usually associated with catecholaminergic surge following myocardial ischaemia and manifest as recurrent ventricular arrhythmias, requiring frequent DC shocks. Delivering repeated DC shocks induces myocardial damage and further worsens the arrhythmias, which are resistant to the antiarrhythmic drugs. Cardiac sympathetic blockade abates the excessive catecholaminergic drive and help pacifying the malignant ventricular arrhythmias. We treated the electrical storm in a 52-year-old male with ultrasound-guided left sympathetic ganglion block followed by surgical left cardiac sympathetic denervation. The patient remained symptom-free without any incident of ventricular arrhythmias for 8 months after the surgery. The ultrasonography during blockade of the stellate ganglion enhances the success rate of the technique, reduces the quantity of local anaesthetic required to produce desired effects and prevents technical complications. Supraclavicular surgical access to the upper thoracic sympathetic chain obviates the necessity for one lung ventilation and lateral decubitus during surgery, when the patient is in hemodynamically unstable condition. Sympathectomy can be performed under general anaesthesia taking cautions to avoid sympathetic stimulation in intraoperative period. PMID:24163457

Gadhinglajkar, Shrinivas; Sreedhar, Rupa; Unnikrishnan, M; Namboodiri, Narayanan

2013-07-01

40

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

PubMed Central

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 diagnostic left-sided cardiac catheterisation. One hundred and twenty eight of these patients had a history of previous myocardial infarction. MAIN OUTCOME MEASURES: The presence of normal and impaired left ventricular function, as evaluated by logistic regression analysis and estimation of the area under the receiver operating characteristic (ROC) curve (an index of overall diagnostic accuracy). Ventricular function was assessed by the measurement of left ventricular end diastolic pressure and angiographically determined left ventricular ejection fraction. RESULTS: Logistic regression analysis showed that plasma brain natriuretic peptide was the best predictor of increased left ventricular end diastolic pressure (> or = 15 mm Hg) (P < 0.001), decreased left ventricular ejection fraction (< or = 45%) (P < 0.001), and the combination of left ventricular ejection fraction < or = 45% and left ventricular end diastolic pressure > or = 15 mm Hg (P < 0.001). The areas under the ROC function for the detection of left ventricular dysfunction were 0.789 for brain natriuretic peptide, 0.665 for atrial natriuretic factor, and 0.610 for N-terminal pro-atrial natriuretic factor. CONCLUSIONS: Plasma brain natriuretic peptide seemed to be a better indicator of left ventricular function than plasma atrial natriuretic factor or N-terminal pro-atrial natriuretic factor. However, the overall diagnostic accuracy of circulating atrial natriuretic factor, N-terminal pro-atrial natriuretic factor, and brain natriuretic peptide as indicators of normal and impaired ventricular function in an unselected group of patients with coronary heart disease and a high frequency of previous myocardial infarction was relatively modest. PMID:8868981

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

1996-01-01

41

Synthetic prostacycline agonist, ONO-1301, ameliorates left ventricular dysfunction and cardiac fibrosis in cardiomyopathic hamsters.  

PubMed

Impairment of cardiac function in cardiomyopathy has been postulated to be related to decreased blood flow and increased collagen synthesis. Administration of growth factors was reported to attenuate left ventricular (LV) remodeling and dysfunction in animal models of dilated cardiomyopathy. We previously reported that ONO-1301, a synthetic prostacyclin agonist with thromboxane-synthase inhibitory activity, promotes production of hepatocyte growth factor and vascular endothelial growth factor from various cell types and ameliorate ischemia-induced LV dysfunction in mice and pigs. We evaluated therapeutic efficacy of ONO-1301 in the Syrian hamster (TO-2), a model of genetically determined dilated cardiomyopathy. Either vehicle or a slow releasing form of ONO-1301 (ONO-1301-PLGA, 10mg/kg/3 weeks) was administered subcutaneously every 3 weeks to TO-2 hamsters from 24 to 32 weeks of age (n=12 for each group). Age-matched F1B hamsters were used as a control. Plasma concentration of HGF was elevated in ONO-1301-PLGA group (p<0.05). Echocardiographic study demonstrated that LV fractional shortening was significantly improved in the ONO-1301-PLGA group (25+/-4%, p<0.01) compared with that in the vehicle group (19+/-2%). Cardiac fibrosis was significantly reduced by ONO-1301-PLGA (p<0.05) as determined by Azan-Mallory staining. Capillary density of left ventricle was markedly reduced in TO-2 hamsters. ONO-1301-PLGA significantly increased capillary density in TO-2 group (p<0.05). ONO-1301 improved LV dysfunction and reduced cardiac fibrosis in the hamster model of dilated cardiomyopathy. ONO-1301 might hold a therapeutic potential in the treatment of dilated cardiomyopathy. PMID:19906506

Hirata, Yoichiro; Soeki, Takeshi; Akaike, Masashi; Sakai, Yoshiki; Igarashi, Takashi; Sata, Masataka

2009-12-01

42

The left ventricular lead electrical delay predicts response to cardiac resynchronisation therapy.  

PubMed

Up to one-third of patients who undergo cardiac resynchronisation therapy (CRT) are not responders. To identify potential responders to CRT may be sometimes difficult and time-consuming. Forty-five patients who had undergone CRT implantation for standard indications were evaluated. Electrical left ventricular (LV) lead location was assessed by left ventricular activation time (LVAT), LV lead electrical delay (LVLED), and RV-LV interlead electrical delay (RVsense-LVsense). Anatomic LV pacing location was assessed as basal or mid-ventricular between 3:00 to 5:00 (traditionally optimal site), and all the other positions (traditionally non-optimal site). CRT response was defined as a decrease in LV end-systolic volume (LVESV) exceeding 15% at six months. LVLED was larger in the responder group than that in the non-responder group (67.3±8.5% vs. 55.3±8.1%, P< 0.001). In the multivariate analysis, LVLED and cLBBB morphology were the two independent predictors of positive echocardiographic response to CRT (OR=1.180, P=0.003; OR=7.497, P=0.04, respectively). A cutoff value of LVLED> 54.82% predicted responders with 96.3% sensitivity and 75.2% specificity and the area under the receiver operating characteristic (ROC) curve was 0.844 for LVLED (P=0.002). No relationship was found between the anatomic LV pacing sites and response to CRT (P=0.188). The larger left ventricular lead electrical delay may predict response to cardiac resynchronisation therapy. PMID:24996391

Zhang, Hang; Dai, Zhenlin; Xiao, Pinxi; Pan, Chang; Zhang, Juan; Hu, Zuoying; Chen, Shaoliang

2014-10-01

43

Tomotherapy and Multifield Intensity-Modulated Radiotherapy Planning Reduce Cardiac Doses in Left-Sided Breast Cancer Patients With Unfavorable Cardiac Anatomy  

SciTech Connect

Purpose: For patients with left-sided breast cancers, radiation treatment to the intact breast results in high doses to significant volumes of the heart, increasing the risk of cardiac morbidity, particularly in women with unfavorable cardiac anatomy. We compare helical tomotherapy (TOMO) and inverse planned intensity modulated radiation therapy (IMRT) with three-dimensional conformal radiotherapy using opposed tangents (3D-CRT) for reductions in cardiac volumes receiving high doses. Methods and Materials: Fifteen patients with left-sided breast cancers and unfavorable cardiac anatomy, determined by a maximum heart depth (MHD) of {>=}1.0 cm within the tangent fields, were planned for TOMO and IMRT with five to seven beam angles, in addition to 3D-CRT. The volumes of heart and left ventricle receiving {>=}35 Gy (V35) were compared for the plans, as were the mean doses to the contralateral breast and the volume receiving {>=}20 Gy (V20) for the ipsilateral lung. Results: The mean MHD was 1.7 cm, and a significant correlation was observed between MHD and both heart and left ventricle V35. The V35s for IMRT (0.7%) and TOMO (0.5%) were significantly lower than for 3D-CRT (3.6%). The V20 for IMRT (22%) was significantly higher than for 3D-CRT (15%) or TOMO (18%), but the contralateral breast mean dose for TOMO (2.48 Gy) was significantly higher than for 3D-CRT (0.93 Gy) or IMRT (1.38 Gy). Conclusions: Both TOMO and IMRT can significantly reduce cardiac doses, with modest increases in dose to other tissues in left-sided breast cancer patients with unfavorable cardiac anatomy.

Coon, Alan B., E-mail: Alan_Coon@rush.ed [Department of Radiation Oncology, Rush University Medical Center, Chicago, IL (United States); Dickler, Adam [Department of Radiation Oncology, Little Company of Mary Hospital, Evergreen Park, IL (United States); Kirk, Michael C. [Massachusetts General/North Shore Cancer Center, Danvers, MA (United States); Liao Yixiang; Shah, Anand P.; Strauss, Jonathan B.; Chen, Sea; Turian, Julius; Griem, Katherine L. [Department of Radiation Oncology, Rush University Medical Center, Chicago, IL (United States)

2010-09-01

44

Cardiac gated ventilation  

SciTech Connect

There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. The authors evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50 msec scan aperture. Multi slice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart.

Hanson, C.W. III [Hospital of the Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. Anesthesia; Hoffman, E.A. [Univ. of Iowa College of Medicine, Iowa City, IA (United States). Div. of Physiologic Imaging

1995-12-31

45

Cardiac gated ventilation  

NASA Astrophysics Data System (ADS)

There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. We evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50msec scan aperture. Multislice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. We observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a nonfailing model of the heart.

Hanson, C. William, III; Hoffman, Eric A.

1995-05-01

46

The impact of acute reduction of continuous-flow left ventricular assist device support on cardiac and exercise performance  

Microsoft Academic Search

BackgroundThe use of the HeartMate II continuous-flow left ventricular assist device (LVAD) improves survival, quality of life and functional capacity of patients with advanced heart failure. However, no study so far has shown the benefits of these devices for cardiac function during peak exercise.ObjectiveTo assess cardiac and exercise performance in patients implanted with the HeartMate II LVAD under two settings:

Djordje G Jakovljevic; Robert S George; David Nunan; Gay Donovan; Robert S Bougard; Magdi H Yacoub; Emma J Birks; David A Brodie

2010-01-01

47

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. PMID:22883134

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

48

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. PMID:19837897

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

2009-01-01

49

Natakalim improves post-infarction left ventricular remodeling by restoring the coordinated balance between endothelial function and cardiac hypertrophy  

PubMed Central

Endothelial dysfunction can lead to congestive heart failure and the activation of endothelial ATP-sensitive potassium (KATP) channels may contribute to endothelial protection. Therefore, the present study was carried out to investigate the hypothesis that natakalim, a novel KATP channel opener, ameliorates post-infarction left ventricular remodeling and failure by correcting endothelial dysfunction. The effects of myocardial infarction were assessed 8 weeks following left anterior descending coronary artery occlusion in male Wistar rats. Depressed blood pressure, cardiac dysfunction, evidence of left ventricular remodeling and congestive heart failure were observed in the rats with myocardial infarction. Treatment with natakalim at daily oral doses of 1, 3 or 9 mg/kg/day for 8 weeks prevented these changes. Natakalim also prevented the progression to cardiac failure, which was demonstrated by the increase in right ventricular weight/body weight (RVW/BW) and relative lung weight, signs of cardiac dysfunction, as well as the overexpression of atrial and brain natriuretic peptide mRNAs. Our results also demonstrated that natakalim enhanced the downregulation of endothelium-derived nitric oxide, attenuated the upregulation of inducible nitric oxide synthase-derived nitric oxide (NO), inhibited the upregulated endothelin system and corrected the imbalance between prostacyclin and thromboxane A2. Overall, our findings suggest that natakalim prevents post-infarction hypertrophy and cardiac failure by restoring the coordinated balance between endothelial function and cardiac hypertrophy. PMID:25215478

ZHOU, HONG-MIN; ZHONG, MING-LI; ZHANG, YAN-FANG; CUI, WEN-YU; LONG, CHAO-LIANG; WANG, HAI

2014-01-01

50

Natakalim improves post-infarction left ventricular remodeling by restoring the coordinated balance between endothelial function and cardiac hypertrophy.  

PubMed

Endothelial dysfunction can lead to congestive heart failure and the activation of endothelial ATP-sensitive potassium (KATP) channels may contribute to endothelial protection. Therefore, the present study was carried out to investigate the hypothesis that natakalim, a novel KATP channel opener, ameliorates post-infarction left ventricular remodeling and failure by correcting endothelial dysfunction. The effects of myocardial infarction were assessed 8 weeks following left anterior descending coronary artery occlusion in male Wistar rats. Depressed blood pressure, cardiac dysfunction, evidence of left ventricular remodeling and congestive heart failure were observed in the rats with myocardial infarction. Treatment with natakalim at daily oral doses of 1, 3 or 9 mg/kg/day for 8 weeks prevented these changes. Natakalim also prevented the progression to cardiac failure, which was demonstrated by the increase in right ventricular weight/body weight (RVW/BW) and relative lung weight, signs of cardiac dysfunction, as well as the overexpression of atrial and brain natriuretic peptide mRNAs. Our results also demonstrated that natakalim enhanced the downregulation of endothelium-derived nitric oxide, attenuated the upregulation of inducible nitric oxide synthase-derived nitric oxide (NO), inhibited the upregulated endothelin system and corrected the imbalance between prostacyclin and thromboxane A2. Overall, our findings suggest that natakalim prevents post-infarction hypertrophy and cardiac failure by restoring the coordinated balance between endothelial function and cardiac hypertrophy. PMID:25215478

Zhou, Hong-Min; Zhong, Ming-Li; Zhang, Yan-Fang; Cui, Wen-Yu; Long, Chao-Liang; Wang, Hai

2014-11-01

51

The Effects of Training on the Time Components of the Left Ventricle, and Cardiac Time Components: Sedentary versus Active Individuals.  

ERIC Educational Resources Information Center

A review of previous research was completed to determine (a) the response of the cardiac time components of the left ventricle to varying types and intensities of training programs, (b) the probable physiological explanations for these responses, and (c) the significance of the changes which did or did not occur. It was found that, at rest,…

Plowman, Sharon Ann

52

Left ventricular geometric remodeling in relation to non-ischemic scar pattern on cardiac magnetic resonance imaging.  

PubMed

Left ventricular (LV) remodeling and myocardial fibrosis have been linked to adverse heart failure outcomes. Mid wall late gadolinium enhancement (MW-LGE) on cardiac magnetic resonance (CMR) imaging is well-associated with non-ischemic cardiomyopathy (NICM), but prevalence in ischemic cardiomyopathy (ICM) and association with remodeling are unknown. The population comprised patients with systolic dysfunction [LV ejection fraction (LVEF ? 40 %)]. CMR was used to identify MW-LGE, conventionally defined as fibrosis of the mid-myocardial or epicardial aspect of the LV septum. 285 patients were studied. MW-LGE was present in 12 %, and was tenfold more common with NICM (32 %) versus ICM (3 %, p < 0.001). However, owing to higher prevalence of ICM, 15 % of patients with MW-LGE had ICM. LV wall stress was higher (p = 0.02) among patients with, versus those without, MW-LGE despite similar systolic blood pressure (p = 0.24). In multivariate analysis, MW-LGE was associated with CMR-quantified LV end-diastolic volume (p = 0.03) independent of LVEF and mass. Incorporation of clinical and imaging variables demonstrated MW-LGE to be associated with higher LV end-diastolic volume (OR 1.13, CI 1.004-1.27 per 10 ml/m(2), p = 0.04) after controlling for presence of NICM (OR 16.0, CI 5.8-44.1, p < 0.001). While more common in NICM, MW-LGE can occur in ICM and is a marker of LV chamber dilation irrespective of cardiomyopathic etiology. PMID:25008088

Kim, Jiwon; Kochav, Jonathan D; Gurevich, Sergey; Afroz, Anika; Petashnick, Maya; Volo, Samuel; Diaz, Belen; Okin, Peter M; Horn, Evelyn; Devereux, Richard B; Weinsaft, Jonathan W

2014-12-01

53

Differences Between Left and Right Ventricular Chamber Geometry Affect Cardiac Vulnerability to Electric Shocks  

E-print Network

electrical activity. The goal of this study was to use optical imaging experiments and 3-D bidomain of externally-applied field (RV­ or LV­ shocks) alters the shape of the vulnerability area (VA), the 2-D grid linked. A large body of research has demonstrated that ventricular fibrillation induction

54

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. PMID:20378644

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

2010-01-01

55

Simultaneous noninvasive measurement of blood flow in the great cardiac vein and left anterior descending artery.  

PubMed

Magnetic resonance (MR) flow mapping can be used to quantify flow velocity and volume flow in the coronary vessels noninvasively. The close anatomic relationship of the left anterior descending artery (LAD) with the great cardiac vein (GCV) allows imaging of both in one view. We examined the feasibility to discriminate between these two vessels based on the flow pattern and to measure the flow quantitatively. Eleven individuals with a normal LAD and 8 patients with a diseased LAD underwent MR imaging. From MR angiograms using connectivity to the aortic root, differentiation between the LAD and GCV was obtained. Perpendicular to both vessels, phase-contrast velocity mapping was performed to measure phasic and mean volume flow. After correction for cardiac motion of the vessel, GCV flow was found to be mainly systolic and pointing in the inverse direction as the predominantly diastolic flow in the LAD. These criteria appeared valid in all subjects, even in cases of highly stenotic arteries. The volume flow measurements corrected for body surface area were 31+/-15 ml/min/m2 in the normal LAD (n = 11) and 21+/-10 ml/min/m2 in the diseased LAD (n = 7). The volume flow measurements in the GCV corrected for body surface area were 23+/-19 ml/min/m2 in the normal vessels and 19+/-16 ml/min/m2 in the diseased vessels. In the patient with an occluded LAD and collaterals, the volume flow in the GCV was 7 ml/min/m2. MR is a unique tool for noninvasive simultaneous measurement of the flow pattern and volume flow in the GCV and the LAD, showing a clear distinction between arterial and venous flow. PMID:11816619

Bedaux, W L; Hofman, M B; Visser, C A; van Rossum, A C

2001-01-01

56

Scintigraphic evaluation of left ventricular function and correlation with autonomic cardiac neuropathy in diabetic patients.  

PubMed

Left ventricular function of 20 diabetic patients was investigated at rest and during hand-grip test using radionuclide ventriculography. The aim of the study was to discuss the correlation of cardiac function with autonomic cardiac neuropathy (ACN) in diabetic subjects. ACN was tested using heart rate response to valsalva maneuver, standing up, deep breathing; blood pressure response to standing up, sustained hand-grip, and additionally corrected QT (QTc) measurements. Plasma glucose regulation was screened with fructosamine levels. Ejection fraction (EF), peak ejection (PER) and filling rates (PFR), times to peak ejection (TPE) and filling (TPF), time to endsystole (TES), TES/T, TPE/T, TPF/T, 1/3 PER, 1/3 PFR, 1/3 EF, 1/3 FF (filling fraction) we calculated. Thirteen patients had ACN. Six patients (30%) had a low EF at rest. As a response to hand-grip, 14 patients (70%) showed a decrease in EF (9 ACN). PFR was low in 10 patients (50%) at rest and in 12 (60%) during hand-grip. The mean rest PER value of ACN+ patients (4.4 +/- 1.3) was significantly higher than that of controls (2.9 +/- 0.5) and patients without ACN (3.4 +/- 0.4; p < 0.05) as well as the mean 1/3 PER value (1.7 +/- 0.5 vs. 1.3 +/- 0.5; p < 0.05). Fourteen patients (70%) had a fall in PER 10 ACN) as a response to hand-grip. The mean TES/T value of patients with ACN (0.44 +/- 0.05) was significantly higher than of those without ACN (0.38 +/- 0.05; p < 0.05). In conclusion, diastolic dysfunction was detected frequently at rest. Systolic parameters were markedly impaired as a response to hand-grip in patients with ACN. Sympathetic overactivity was noted in ACN+ group at rest. Our results indicated that the patients with diabetes and ACN have subclinical left ventricular diastolic dysfunction and symphatic overactivity. PMID:1335838

Erbas, T; Erbas, B; Gedik, O; Biberoglu, S; Bekdik, C F

1992-01-01

57

Stimulus Intensity in Left Ventricular Leads and Response to Cardiac Resynchronization Therapy  

PubMed Central

Background Increased left ventricular (LV) stimulus intensity has been shown to improve conduction velocity and cardiac output. However, high-output pacing would shorten device battery life. Our prospective trial analyzed the clinical effects of high- versus low-output LV pacing. Methods and Results Thirty-nine patients undergoing initial cardiac resynchronization therapy device implantation with bipolar LV leads were assigned to 3 months of either high-output LV pacing (Hi) or low-output LV pacing (Lo) in a randomized, blinded crossover fashion. Hi and Lo settings were determined with a rigorous intraoperative protocol specific to each patient. Clinical and echocardiographic data were obtained at randomization, at 3 months, and a subsequent 3 months after crossover. Mean age was 66.4±9.8 years, and mean QRS duration was 159.3±23.1 ms. Compared to baseline, both arms had significant improvements in Minnesota Living With Heart Failure score (given as mean [95% confidence interval]) (baseline versus Lo: 43.3 [35.5 to 51.1] versus 21.3 [14.6 to 28.0], P<0.01; baseline versus Hi: 43.3 [35.5 to 51.1] versus 23.6 [16.1 to 31.1], P<0.01) and 6-minute walk distance (baseline versus Lo: 692 ft [581 to 804] versus 995 ft [876 to 1114], P<0.01; baseline versus Hi: 699 ft [585 to 813] versus 982 ft [857 to 1106], P<0.01). Although both Hi and Lo arms had some echocardiographic parameters that significantly improved compared to baseline (baseline end-diastolic diameter 5.7 cm [5.5 to 6.0] versus Lo 5.5 cm [5.1 to 5.8], P<0.01; baseline end-systolic diameter 4.9 cm [4.6 to 5.3] versus Hi 4.7 cm [4.3 to 5.0], P<0.05), there were no significant differences observed when comparing the Hi- versus Lo-output arms. Conclusions Low-output LV pacing with a relatively narrow safety margin above capture threshold affords significant improvement from baseline and is clinically equivalent to high-output LV pacing. These data support a strategy of minimizing the programmed LV safety margin to increase battery life in cardiac resynchronization therapy devices. Clinical Trial Registration Information URL: http://www.clinicaltrials.gov. Unique identifier: NCT01060449 PMID:23316285

Bavikati, Venkata V.; Langberg, Jonathan J.; Williams, B. Robinson; Kella, Danesh; Lloyd, Michael S.

2012-01-01

58

Anomalous left coronary artery connected to the pulmonary artery associated with other cardiac defects: a difficult joint diagnosis.  

PubMed

Anomalous left coronary artery connected to the pulmonary artery (ALCAPA) can be associated rarely with other congenital heart defects. The preoperative joint diagnosis is challenging. From 1987 to 2012, a retrospective bicentric assessment of 12 patients with ALCAPA related to other cardiac defects focused on the associated heart defect, the moment of complete diagnosis related to surgery, and outcome. Coarctation was the most frequently associated heart defect (n = 5) followed by tetralogy of Fallot with or without pulmonary atresia (n = 3). The study group comprised one case of hypoplastic left heart syndrome, one right aortic arch, one congenital mitral malformation, and one infant with divided left atrium and anomalous pulmonary venous return. Only four patients had a complete diagnosis of both the cardiac defect and the coronary abnormality before surgery. In two cases, the coronary anomaly was discovered during surgery performed for another cardiac defect and treated at the same time. The diagnosis of the six remaining patients was determined after cardiac repair. Of the 12 patients, 7 (58 %) died after surgery. Half of these patients died within the first 30 days after repair. At this writing, the remaining patients are in good health after a median follow-up period of 5.4 years (range, 2.1-8.5 years). This study confirmed that ALCAPA associated with other cardiac defects often is misdiagnosed before surgery, mostly due to specific hemodynamics masking myocardial ischemia preoperatively. Survival was compromised due to the unrecognized diagnosis of an associated coronary abnormality but also because of midterm complications related to the other cardiac defects. PMID:24898291

Laux, Daniela; Bertail, Claire; Bajolle, Fanny; Houyel, Lucile; Boudjemline, Younes; Bonnet, Damien

2014-10-01

59

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. PMID:23138590

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

2012-01-01

60

Surviving sudden cardiac death secondary to anomalous left coronary artery from the pulmonary artery: a case report and literature review.  

PubMed

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is an uncommon type of congenital coronary anomaly. In adults, the clinical picture of ALCAPA varies widely between being asymptomatic, presenting similarly to other heart diseases, or as malignant arrhythmias. Patients who have cardiac arrest are usually young and do not exhibit prior warning symptoms. In this article we describe a case of a 22-year-old healthy male, who experienced cardiac arrest during exertion. He was then diagnosed with ALCAPA, which was surgically corrected. PMID:25012636

Alsara, Osama; Kalavakunta, Jagadeesh K; Hajjar, Victor; Alsarah, Ahmad; Cho, Nam; Dhar, Gaurav

2014-01-01

61

Effect of right ventricular pacing lead on left ventricular dyssynchrony in patients receiving cardiac resynchronization therapy.  

PubMed

Right ventricular (RV) pacing-induced left ventricular (LV) dyssynchrony can be 1 reason of nonresponse to cardiac resynchronization therapy (CRT) by potentially interfering with spontaneous dyssynchrony. We investigated the effect of the RV pacing lead on LV dyssynchrony in patients receiving CRT. LV radial dyssynchrony was assessed in a 16-segment model by using the novel speckle-tracking imaging before CRT and after the procedure, when the device was randomized to biventricular and RV pacing with crossover after 48 hours. LV lead tip was localized under fluoroscopic guidance. Of 43 patients, 30 (70%) acutely responded to CRT by a decrease in end-systolic volume >10%. RV pacing did not significantly increase the magnitude but altered the pattern of intraventricular dyssynchrony in the overall study group. During RV pacing, major shifts in the latest activated region occurred in 20 patients. However, LV radial dyssynchrony during spontaneous rhythm, but not the 1 induced by RV pacing, predicted response to CRT. When lead localization was optimal according to spontaneous dyssynchrony, response rate was 89% compared with 50% when lead localization was not optimal (p = 0.01). In contrast, when lead localization was optimal according to RV pacing-induced dyssynchrony, response rate was 81% compared with 67% when lead localization was not optimal (p = NS). In conclusion, RV apical pacing can alter the pattern of spontaneous LV dyssynchrony in patients receiving CRT. However, this alteration does not detract from the value of assessing LV dyssynchrony during spontaneous rhythm to predict responders to CRT. PMID:19231336

Sade, Leyla Elif; Demir, Ozlem; Atar, Ilyas; Müderriso?lu, Haldun; Ozin, Bülent

2009-03-01

62

Unprotected left main coronary artery percutaneous coronary intervention in a pediatric patient with cardiac allograft vasculopathy.  

PubMed

Cardiac allograft vasculopathy (CAV) is an immunologically-mediated phenomenon that occurs in up to 50% of patients surviving to 10 years post orthotopic heart transplant (OHT). While the pediatric subgroup of OHT recipients has a lower overall prevalence of CAV, prognosis is poor after development, with a 24% mortality within 2 years of diagnosis. Medical therapy, including statins, remains the mainstay of treatment. Diffuse intimal thickening often precludes coronary artery bypass grafting, while repeat OHT is associated with inferior outcomes including increased mortality. Percutaneous coronary intervention (PCI) is a therapeutic option for CAV with excellent initial success rates, but higher rates of major adverse cardiovascular events. Despite these challenges, PCI may be performed safely and can serve as a palliative bridge for repeat OHT. There is a paucity of data on PCI for CAV of the unprotected left main coronary artery (ULMCA). We report the case of a 13-year-old female with CAV involving the distal bifurcation of the ULMCA who underwent PCI with drug-eluting stents. While these cases are technically challenging, strategies that may predict success include an appropriately selected patient, use of predictive models for outcomes assessment, and operator expertise. PMID:25364007

Tadwalkar, Rigved V; Lee, Michael S

2014-11-01

63

Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function  

PubMed Central

In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart. PMID:23743396

Yotti, Raquel; del Villar, Candelas Perez; del Alamo, Juan C.; Rodriguez-Perez, Daniel; Martinez-Legazpi, Pablo; Benito, Yolanda; Carlos Antoranz, J.; Mar Desco, M.; Gonzalez-Mansilla, Ana; Barrio, Alicia; Elizaga, Jaime; Fernandez-Aviles, Francisco

2013-01-01

64

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. PMID:20798785

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

2010-01-01

65

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein  

PubMed Central

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart. PMID:25379351

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

66

Association Between Tangential Beam Treatment Parameters and Cardiac Abnormalities After Definitive Radiation Treatment for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To examine the association between radiation treatment (RT) parameters, cardiac diagnostic test abnormalities, and clinical cardiovascular diagnoses among patients with left-sided breast cancer after breast conservation treatment with tangential beam RT. Methods and Materials: The medical records of 416 patients treated between 1977 and 1995 with RT for primary left-sided breast cancer were reviewed for myocardial perfusion imaging and echocardiograms. Sixty-two patients (62/416, 15%) underwent these cardiac diagnostic tests for cardiovascular symptoms and were selected for further study. Central lung distance and maximum heart width and length in the treatment field were determined for each patient. Medical records were reviewed for cardiovascular diagnoses and evaluation of cardiac risk factors. Results: At a median of 12 years post-RT the incidence of cardiac diagnostic test abnormalities among symptomatic left-sided irradiated women was significantly higher than the predicted incidence of cardiovascular disease in the patient population, 6/62 (9%) predicted vs. 24/62 (39%) observed, p 0.001. As compared with patients with normal tests, patients with cardiac diagnostic test abnormalities had a larger median central lung distance (2.6 cm vs. 2.2 cm, p = 0.01). Similarly, patients with vs. without congestive heart failure had a larger median central lung distance (2.8 cm vs. 2.3 cm, p = 0.008). Conclusions: Contemporary RT for early breast cancer may be associated with a small, but potentially avoidable, risk of cardiovascular morbidity that is associated with treatment technique.

Correa, Candace R. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Das, Indra J. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)], E-mail: Das@xrt.upenn.edu; Litt, Harold I. [Department of Radiology-Cardiovascular Imaging Section, University of Pennsylvania, Philadelphia, PA (United States); Ferrari, Victor [Department of Medicine-Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, PA (United States); Hwang, W.-T. [Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA (United States); Solin, Lawrence J.; Harris, Eleanor E. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)

2008-10-01

67

Cardiac Endothelin System Impairs Left Ventricular Function in Renin-Dependent Hypertension via Decreased Sarcoplasmic Reticulum Ca21 Uptake  

Microsoft Academic Search

Background—We evaluated the role of the cardiac endothelin (ET) system in compensated hypertensive left ventricular (LV) hypertrophy (LVH) and after the transition toward LV dysfunction. Methods and Results—Hypertensive transgenic rats overexpressing the Ren2 gene (Ren2 rats) were investigated between the ages of 10 and 30 weeks (Ren2-10 and Ren2-30 groups, respectively) and compared with age-matched normotensive Sprague-Dawley (SD) rats (SD-10

Lars Rothermund; Yigal M. Pinto; Berthold Hocher; Roland Vetter; Stefan Leggewie; Hans-Dieter Orzechowski; Reinhold Kreutz; Martin Paul

68

Effect of cardiac resynchronization therapy in patients without left intraventricular dyssynchrony  

PubMed Central

Aims To evaluate the effects of cardiac resynchronization therapy (CRT) on long-term survival of patients without baseline left ventricular (LV) mechanical dyssynchrony. Methods and results A total of 290 heart failure patients (age 67 ± 10 years, 77% males) without significant baseline LV dyssynchrony (<60 ms as assessed with tissue Doppler imaging) were treated with CRT. Patients were divided according to the median LV dyssynchrony measured after 48 h of CRT into two groups. All-cause mortality was compared between the subgroups. In addition, the all-cause mortality rates of these subgroups were compared with the all-cause mortality of 290 heart failure patients treated with CRT who showed significant LV dyssynchrony (?60 ms) at baseline. In the group of patients without significant LV dyssynchrony, median LV dyssynchrony increased from 22 ms (inter-quartile range 16–34 ms) at baseline to 40 ms (24–56 ms) 48 h after CRT. The cumulative mortality rates at 1-, 2-, and 3-year follow-up of patients with LV dyssynchrony ?40 ms 48 h after CRT implantation were significantly higher when compared with patients with LV dyssynchrony <40 ms (10, 17, and 23 vs. 3, 8, and 10%, respectively; log-rank P< 0.001). Finally, the cumulative mortality rates at 1-, 2-, and 3-year follow-up of patients with baseline LV dyssynchrony were 3, 8, and 11%, respectively (log-rank P= 0.375 vs. patients with LV dyssynchrony <40 ms). Induction of LV dyssynchrony after CRT was an independent predictor of mortality (hazard ratio: 1.247; P= 0.009). Conclusion In patients without significant LV dyssynchrony, the induction of LV dyssynchrony after CRT may be related to a less favourable long-term outcome. PMID:22279110

Auger, Dominique; Bleeker, Gabe B.; Bertini, Matteo; Ewe, See H.; van Bommel, Rutger J.; Witkowski, Tomasz G.; Ng, Arnold C.T.; van Erven, Lieselot; Schalij, Martin J.; Bax, Jeroen J.; Delgado, Victoria

2012-01-01

69

Effects of cyclooxygenase-2 gene inactivation on cardiac autonomic and left ventricular function in experimental diabetes  

PubMed Central

Glucose-mediated oxidative stress and the upregulation of cyclooxygenase (COX)-2 pathway activity have been implicated in the pathogenesis of several vascular complications of diabetes including diabetic neuropathy. However, in nondiabetic subjects, the cardiovascular safety of selective COX-2 inhibition is controversial. The aim of this study was to explore the links between hyperglycemia, oxidative stress, activation of the COX-2 pathway, cardiac sympathetic integrity, and the development of left ventricular (LV) dysfunction in experimental diabetes. R wave-to-R wave interval (R-R interval) and parameters of LV function measured by echocardiography using 1% isoflurane, LV sympathetic nerve fiber density, LV collagen content, and markers of myocardial oxidative stress, inflammation, and PG content were assessed after 6 mo in control and diabetic COX-2-deficient (COX-2?/?) and littermate, wild-type (COX-2+/+) mice. There were no differences in blood glucose, LV echocardiographic measures, collagen content, sympathetic nerve fiber density, and markers of oxidative stress and inflammation between nondiabetic (ND) COX-2+/+ and COX-2?/? mice at baseline and thereafter. After 6 mo, diabetic COX-2+/+ mice developed significant deteriorations in the R-R interval and signs of LV dysfunction. These were associated with a loss of LV sympathetic nerve fiber density, increased LV collagen content, and a significant increase in myocardial oxidative stress and inflammation compared with those of ND mice. Diabetic COX-2?/? mice were protected against all these biochemical, structural, and functional deficits. These data suggest that in experimental diabetes, selective COX-2 inactivation confers protection against sympathetic denervation and LV dysfunction by reducing intramyocardial oxidative stress, inflammation, and myocardial fibrosis. PMID:19060127

Kellogg, Aaron P.; Converso, Kimber; Wiggin, Tim; Stevens, Martin; Pop-Busui, Rodica

2009-01-01

70

Effects of cyclooxygenase-2 gene inactivation on cardiac autonomic and left ventricular function in experimental diabetes.  

PubMed

Glucose-mediated oxidative stress and the upregulation of cyclooxygenase (COX)-2 pathway activity have been implicated in the pathogenesis of several vascular complications of diabetes including diabetic neuropathy. However, in nondiabetic subjects, the cardiovascular safety of selective COX-2 inhibition is controversial. The aim of this study was to explore the links between hyperglycemia, oxidative stress, activation of the COX-2 pathway, cardiac sympathetic integrity, and the development of left ventricular (LV) dysfunction in experimental diabetes. R wave-to-R wave interval (R-R interval) and parameters of LV function measured by echocardiography using 1% isoflurane, LV sympathetic nerve fiber density, LV collagen content, and markers of myocardial oxidative stress, inflammation, and PG content were assessed after 6 mo in control and diabetic COX-2-deficient (COX-2(-/-)) and littermate, wild-type (COX-2(+/+)) mice. There were no differences in blood glucose, LV echocardiographic measures, collagen content, sympathetic nerve fiber density, and markers of oxidative stress and inflammation between nondiabetic (ND) COX-2(+/+) and COX-2(-/-) mice at baseline and thereafter. After 6 mo, diabetic COX-2(+/+) mice developed significant deteriorations in the R-R interval and signs of LV dysfunction. These were associated with a loss of LV sympathetic nerve fiber density, increased LV collagen content, and a significant increase in myocardial oxidative stress and inflammation compared with those of ND mice. Diabetic COX-2(-/-) mice were protected against all these biochemical, structural, and functional deficits. These data suggest that in experimental diabetes, selective COX-2 inactivation confers protection against sympathetic denervation and LV dysfunction by reducing intramyocardial oxidative stress, inflammation, and myocardial fibrosis. PMID:19060127

Kellogg, Aaron P; Converso, Kimber; Wiggin, Tim; Stevens, Martin; Pop-Busui, Rodica

2009-02-01

71

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. PMID:23248509

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

2012-01-01

72

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

73

Correlation-based discrimination between cardiac tissue and blood for segmentation of the left ventricle in 3-D echocardiographic images.  

PubMed

For automated segmentation of 3-D echocardiographic images, incorporation of temporal information may be helpful. In this study, optimal settings for calculation of temporal cross-correlations between subsequent time frames were determined, to obtain the maximum cross-correlation (MCC) values that provided the best contrast between blood and cardiac tissue over the entire cardiac cycle. Both contrast and boundary gradient quality measures were assessed to optimize MCC values with respect to signal choice (radiofrequency or envelope data) and axial window size. Optimal MCC values were incorporated into a deformable model to automatically segment the left ventricular cavity. MCC values were tested against, and combined with, filtered, demodulated radiofrequency data. Results reveal that using envelope data in combination with a relatively small axial window (0.7-1.25 mm) at fine scale results in optimal contrast and boundary gradient between the two tissues over the entire cardiac cycle. Preliminary segmentation results indicate that incorporation of MCC values has additional value for automated segmentation of the left ventricle. PMID:24412178

Saris, Anne E C M; Nillesen, Maartje M; Lopata, Richard G P; de Korte, Chris L

2014-03-01

74

Quantitative analysis of cardiac left ventricular variables obtained by MRI at 3 T: a pre- and post-contrast comparison  

PubMed Central

Short-axis cine images are acquired during cardiac MRI in order to determine variables of cardiac left ventricular (LV) function such as ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and LV mass. In cardiac perfusion assessments this imaging can be performed in the temporal window between first pass perfusion and the acquisition of delayed enhancement images in order to minimise overall scanning time. The objective of this study was to compare pre- and post-contrast short-axis LV variables of 15 healthy volunteers using a two-dimensional cardiac-gated segmented cine true fast imaging with steady state precession sequence and a 3.0 T MRI unit in order to determine the possible effects of contrast agent on the calculated cardiac function variables. Image analysis was carried out using semi-automated software. The calculated mean LV mass was lower when derived from the post-contrast images, relative to those derived pre-contrast (102 vs 108.1 g, p<0.0001). Small but systematic significant differences were also found between the mean pre- and post-contrast values of EF (69.4% vs 68.7%, p<0.05), EDV (142.4 vs 143.7 ml, p<0.05) and ESV (44.2 vs 45.5 ml, p<0.005), but no significant differences in SV were identified. This study has highlighted that contrast agent delivery can influence the numerical outcome of cardiac variables calculated from MRI and this was particularly noticeable for LV mass. This may have important implications for the correct interpretation of patient data in clinical studies where post-contrast images are used to calculate LV variables, since LV normal ranges have been traditionally derived from pre-contrast data sets. PMID:22745212

Matthew, S; Gandy, S J; Nicholas, R S; Waugh, S A; Crowe, E A; Lerski, R A; Dunn, M H; Houston, J G

2012-01-01

75

Acute Impact of Pacing at Different Cardiac Sites on Left Ventricular Rotation and Twist in Dogs  

PubMed Central

Objectives We evaluated the acute impact of different cardiac pacing sites on two-dimensional speckle-tracking echocardiography (STE) derived left ventricular (LV) rotation and twist in healthy dogs. Methods Twelve dogs were used in this study. The steerable pacing electrodes were positioned into right heart through the superior or inferior vena cava, into LV through aorta across the aortic valve. The steerable pacing electrodes were positioned individually in the right atrium (RA), right ventricular apex (RVA), RV outflow tract (RVOT), His bundle (HB), LV apex (LVA) and LV high septum (LVS), individual pacing mode was applied at 10 minutes interval for at least 5 minutes from each position under fluoroscopy and ultrasound guidance and at stabilized hemodynamic conditions. LV short-axis images at the apical and basal levels were obtained during sinus rhythm and pacing. Offline STE analysis was performed. Rotation, twist, time to peak rotation (TPR), time to peak twist (TPT), and apical-basal rotation delay (rotational synchronization index, RSI) values were compared at various conditions. LV pressure was monitored simultaneously. Results Anesthetic death occurred in 1 dog, and another dog was excluded because of bad imaging quality. Data from 10 dogs were analyzed. RVA, RVOT, HB, LVA, LVS, RARV (RA+RVA) pacing resulted in significantly reduced apical and basal rotation and twist, significantly prolonged apical TPR, TPT and RSI compared to pre-pacing and RA pacing (all P<0.05). The apical and basal rotation and twist values were significantly higher during HB pacing than during pacing at ventricular sites (all P<0.05, except basal rotation at RVA pacing). The apical TPR during HB pacing was significantly shorter than during RVOT and RVA pacing (both P<0.05). The LV end systolic pressure (LVESP) was significantly lower during ventricular pacing than during pre-pacing and RA pacing. Conclusions Our results show that RA and HB pacing results in less acute reduction on LV twist, rotation and LVESP compared to ventricular pacing. PMID:25340769

Yu, Yi; Guo, Kai; Li, Wei; Zhang, Rui; Zhang, Peng-Pai; Li, Yi-Gang

2014-01-01

76

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

77

A young patient with coronary artery anomaly, whose left anterior descending artery originated from the pulmonary artery, underwent cardiac arrest.  

PubMed

A rare congenital anomaly of the coronary arteries, in which the left coronary arterial system starts from the arteria pulmonalis, is known as Bland-White-Garland (BWG) syndrome. Isolated left anterior descending (LAD) or circumflex (Cx) arteries originating from the pulmonary artery are even more rare. These anomalies may cause myocardial ischaemia, myocardial infarction, arrhythmia and sudden death. Even if the patient is asymptomatic, he/she should undergo corrective surgery. Here we present the case of an 18-year-old male who survived sudden cardiac arrest during exercise. We identified intra-myocardial blood flow from transthoracic echocardiography, and performed coronary and computed tomographic (CT) angiography, which showed that all the coronary arteries were ectatic and curly and there were disseminated collaterals among the coronary arteries. We diagnosed 'anomalous left coronary artery from the pulmonary artery' (ALCAPA) syndrome, as additionally, the LAD originated from the pulmonary artery. We treated the patient with a left internal mammarian artery - left anterior descending artery (LIMA-LAD) graft. PMID:23044527

Sahin, Tayfun; Bozyel, Serdar; Acar, Eser; Bildirici, Ulas; Yavuz, Sadan; Baris, Ozgur; Ural, Ertan; Ural, Dilek

2012-09-01

78

Increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (Igf-I) expression accompany low heart rate in hibernating grizzly bears.  

PubMed

Grizzly bears (Ursus arctos horribilis) tolerate extended periods of extremely low heart rate during hibernation without developing congestive heart failure or cardiac chamber dilation. Left ventricular atrophy and decreased left ventricular compliance have been reported in this species during hibernation. We evaluated the myocardial response to significantly reduced heart rate during hibernation by measuring relative myosin heavy-chain (MyHC) isoform expression and expression of a set of genes important to muscle plasticity and mass regulation in the left atria and left ventricles of active and hibernating bears. We supplemented these data with measurements of systolic and diastolic function via echocardiography in unanesthetized grizzly bears. Atrial strain imaging revealed decreased atrial contractility, decreased expansion/reservoir function (increased atrial stiffness), and decreased passive-filling function (increased ventricular stiffness) in hibernating bears. Relative MyHC-? protein expression increased significantly in the atrium during hibernation. The left ventricle expressed 100% MyHC-? protein in both groups. Insulin-like growth factor (IGF-I) mRNA expression was reduced by ?50% in both chambers during hibernation, consistent with the ventricular atrophy observed in these bears. Interestingly, mRNA expression of the atrophy-related ubiquitin ligases Muscle Atrophy F-box (MAFBx) and Muscle Ring Finger 1 did not increase, nor did expression of myostatin or hypoxia-inducible factor 1? (HIF-1?). We report atrium-specific decreases of 40% and 50%, respectively, in MAFBx and creatine kinase mRNA expression during hibernation. Decreased creatine kinase expression is consistent with lowered energy requirements and could relate to reduced atrial emptying function during hibernation. Taken together with our hemodynamic assessment, these data suggest a potential downregulation of atrial chamber function during hibernation to prevent fatigue and dilation due to excessive work against an optimally filled ventricle, a response unpredicted by the Frank-Starling mechanism. PMID:21117961

Barrows, N D; Nelson, O L; Robbins, C T; Rourke, B C

2011-01-01

79

Truncus Arteriosus with Persistent Left Superior Vena Cava: Cardiac Computed Tomography Findings in an Unrepaired Adult Patient  

PubMed Central

Truncus arteriosus (TA), a rare complex congenital cardiac disease in which systemic pulmonary and coronary circulations originate from a common vessel, develops due to failure of separation of the common trunk during embryonic life. In this case report, we discuss a 24-year-old patient with TA in whom a computed tomography angiography was performed. To the best of our knowledge, no case has been reported so far where an adult had combined left superior vena cava and pulmonary vein anomaly. PMID:24228215

Genc, Berhan; Okur, Faik Fevi; Tavl?, Vedide; Solak, Aynur

2013-01-01

80

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

81

Mesenchymal stem cells overexpressing integrin-linked kinase attenuate left ventricular remodeling and improve cardiac function after myocardial infarction.  

PubMed

In the present study, we investigated whether mesenchymal stem cells (MSCs) overexpressing integrin-linked kinase (ILK) might regulate ventricular remodeling and cardiac function in a porcine myocardial infarction model. ILK-modified MSCs (ILK-MSCs) (n = 8), MSCs (n = 8) or placebo (n = 8) were injected into peri-infarct myocardium 7 days after ligation of the left anterior descending coronary artery. ILK expression was confirmed by immunofluorescence, real-time PCR, Western blot analysis, and flow cytometry. In vitro assays indicated increased proliferation and reduced apoptosis of MSCs due to overexpression of ILK. Echocardiographic, single-photon emission computed tomography and positron emission tomography analyses demonstrated preserved cardiac function and myocardial perfusion. Reduced fibrosis, increased cardiomyocyte proliferation, and enhanced angiogenesis were observed in the ILK-MSC group. Reduced apoptosis, as demonstrated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling analysis, was also noted. In conclusion, ILK promotes MSC proliferation and suppresses apoptosis. ILK-MSC transplantation improves ventricular remodeling and cardiac function in pigs after MI. It is associated with increased angiogenesis, reduced apoptosis, and increased cardiomyocyte proliferation. This may represent a new approach to the treatment of post-infarct remodeling and subsequent heart failure. PMID:25134935

Mao, Qing; Lin, Chengxi; Gao, Jianshu; Liang, Xiulin; Gao, Wei; Shen, Li; Kang, Lina; Xu, Biao

2014-12-01

82

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. PMID:24817308

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

2014-01-01

83

Quantitative assessment of left ventricular function with dual-source CT in comparison to cardiac magnetic resonance imaging: initial findings.  

PubMed

Cardiac magnetic resonance imaging and echocardiography are currently regarded as standard modalities for the quantification of left ventricular volumes and ejection fraction. With the recent introduction of dual-source computedtomography (DSCT), the increased temporal resolution of 83 ms should also improve the assessment of cardiac function in CT. The aim of this study was to evaluate the accuracy of DSCT in the assessment of left ventricular functional parameters with cardiac magnetic resonance imaging (MRI) as standard of reference. Fifteen patients (two female, 13 male; mean age 50.8 +/- 19.2 years) underwent CT and MRI examinations on a DSCT (Somatom Definition; Siemens Medical Solutions, Forchheim, Germany) and a 3.0-Tesla MR scanner (Magnetom Trio; Siemens Medical Solutions), respectively. Multiphase axial CT images were analysed with a semiautomatic region growing algorithms (Syngo Circulation; Siemens Medical Solutions) by two independent blinded observers. In MRI, dynamic cine loops of short axis slices were evaluated with semiautomatic contour detection software (ARGUS; Siemens Medical Solutions) independently by two readers. End-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF) and stroke volume (SV) were determined for both modalities, and correlation coefficient, systematic error, limits of agreement and inter-observer variability were assessed. In DSCT, EDV and ESV were 135.8 +/- 41.9 ml and 54.9 +/- 29.6 ml, respectively, compared with 132.1 +/- 40.8 ml EDV and 57.6 +/- 27.3 ml ESV in MRI. Thus, EDV was overestimated by 3.7 ml (limits of agreement -46.1/+53.6), while ESV was underestimated by 2.6 ml (-36.6/+31.4). Mean EF was 61.6 +/- 12.4% in DSCT and 57.9 +/- 9.0% in MRI, resulting in an overestimation of EF by 3.8% with limits of agreement at -14.7 and +22.2%. Rank correlation rho values were 0.81 for EDV (P = 0.0024), 0.79 for ESV (P = 0.0031) and 0.64 for EF (P = 0.0168). The kappa value of inter-observer variability were amounted to 0.85 for EDV, ESV and EF. DSCT offers the possibility to quantify left ventricular function from coronary CT angiography datasets with sufficient diagnostic accuracy, adding to the value of the modality in a comprehensive cardiac assessment. The observed differences in the measured values may be due to different post-processing methods and physiological reactions to contrast material injection without beta-blocker medication. PMID:17909817

Busch, S; Johnson, T R C; Wintersperger, B J; Minaifar, N; Bhargava, A; Rist, C; Reiser, M F; Becker, C; Nikolaou, K

2008-03-01

84

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

85

Deformable left-ventricle mesh model for motion-compensated filtering in cardiac gated SPECT  

PubMed Central

Purpose: In this article, the authors present a motion-compensated spatiotemporal processing algorithm to reduce noise in cardiac gated SPECT. Cardiac gated SPECT data are particularly noisy because the acquired photon data are divided among a number of time frames (gates). Classical spatial reconstruction and processing techniques offer noise reduction but they are usually applied on each frame separately and fail to utilize temporal correlation between frames. Methods: In this work, the authors present a motion-compensated spatiotemporal postreconstruction filter offering noise reduction while minimizing motion-blur artifacts. The proposed method can be used regardless of the type of image-reconstruction method (analytical or iterative). The between-frame volumetric myocardium motion is estimated using a deformable mesh model based on the model of the myocardial surfaces. The estimated motion is then used to perform spatiotemporal filtering along the motion trajectories. Both the motion-estimation and spatiotemporal filtering methods seek to maintain the wall brightening seen during cardiac contraction. Wall brightening is caused by the partial volume effect, which is usually viewed as an artifact; however, wall brightening is a useful signature in clinical practice because it allows the clinician to visualize wall thickening. Therefore, the authors seek in their method to preserve the brightening effect. Results: The authors find that the proposed method offers better noise reduction than several existing methods as quantitatively evaluated by signal-to-noise ratio, bias-variance plots, and ejection fraction analysis as well as on tested clinical data. Conclusions: The proposed method mitigates for noise in cardiac gated SPECT images using a postreconstruction motion-compensated filtering approach. Visual as well as quantitative evaluation show considerable improvement in image quality. PMID:21089783

Marin, Thibault; Brankov, Jovan G.

2010-01-01

86

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

87

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. PMID:24987265

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

2014-01-01

88

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. PMID:25031849

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

2014-01-01

89

Investigation of oxyhemoglobin and carboxyhemoglobin ratios in right and left cardiac blood for diagnosis of fatal hypothermia and death by fire.  

PubMed

Few large-scale investigations have looked at the oxyhemoglobin ratio (%O2-Hb) or the carboxyhemoglobin ratio (%CO-Hb) in fatal hypothermia and death by fire as applicable to forensic medicine. We therefore retrospectively examined right and left cardiac blood samples for both %O2-Hb and %CO-Hb in 690 forensic autopsy cases. We therefore sought to establish reference values for the above forensic diagnoses, to compare %O2-Hb in fatal hypothermia with or without cardiopulmonary resuscitation (CPR), and to compare the relationship between %CO-Hb and smoking history. All %O2-Hb and %CO-Hb data were obtained during or immediately after autopsies using a portable CO-oximeter. Death by carbon monoxide (CO) intoxication and death by fire were excluded from the analysis involving smoking history. In fatal hypothermia, %O2-Hb in the left cardiac blood was significantly higher than that in the right cardiac blood, providing important evidence for fatal hypothermia. Furthermore, %O2-Hb in the left cardiac blood increases with CPR but that in the right cardiac blood increases in parallel. No correlation was observed between rectal temperature and %O2-Hb in the right and left cardiac blood, indicating that it is unlikely that postmortem cooling increases %O2-Hb in cardiac blood. %CO-Hb in smokers was significantly higher than that in non-smokers, although the number of cigarettes smoked did not appear to be significant. When assessing death by fire, we identified that %CO-Hb of >10% was a reliable marker of antemortem CO inhalation, regardless of smoking history. PMID:25048514

Kanto-Nishimaki, Yuko; Saito, Haruka; Watanabe-Aoyagi, Miwako; Toda, Ritsuko; Iwadate, Kimiharu

2014-11-01

90

High Prevalence of Cardiac Parvovirus B19 Infection in Patients With Isolated Left Ventricular Diastolic Dysfunction  

Microsoft Academic Search

Background—The etiology of left ventricular (LV) isolated diastolic dysfunction often remains unclear. In the present study, we report a strong association between parvovirus B19 (PVB19) genomes and isolated LV diastolic dysfunction. Methods and Results—In 70 patients (meanSD age, 4311 years) admitted with exertional dyspnea and\\/or reduced exercise tolerance despite preserved LV systolic contractility (ejection fraction68%), isolated diastolic dysfunction was clinically

C. Tschöpe; C.-T. Bock; M. Kasner; M. Noutsias; D. Westermann; P.-L. Schwimmbeck; M. Pauschinger; W.-C. Poller; U. Kühl; R. Kandolf; H.-P. Schultheiss

2010-01-01

91

Effects of Dobutamine on Left Ventricular Performance, Coronary Dynamics, and Distribution of Cardiac Output in Conscious Dogs  

PubMed Central

The effects of dobutamine ([±]-4-[2-[[3-(p-hydroxyphenyl)-1-methyl propyl] amino] ethyl] pyrocatechol hydrochloride), a new synthetic cardioactive sympathomimetic amine, were examined on direct and continuous measurements of left ventricular (LV) diameter (D), pressures (P), velocity of shortening (V), dP/dt, dP/dt/P, arterial pressure, cardiac output, and regional blood flows in the left circumflex coronary, mesenteric, renal, and iliac beds in healthy, conscious dogs. At the highest dose of dobutamine examined, 40 ?g/kg/min, the drug increased dP/dt/P from 65±3 to 128±4 s-1 and isolength velocity from 72±4 to 120±7 mm/s without affecting LV end diastolic D significantly. Mean arterial P rose from 92±2 to 104±3 mm Hg and heart rate from 78±3 to 111±7 beats/min, while LV end systolic D fell from 24.1±1.4 to 19.9±1.8 mm, reflecting a rise in stroke volume from 30±4 to 42±3 ml. Cardiac output rose from 2.41±0.23 to 4.35±0.28 liter/min, while calculated total peripheral resistance declined from 0.042±0.005 to 0.028±0.003 mm Hg/ml/min. The greatest increases in flow and decreases in calculated resistance occurred in the iliac and coronary beds, and the least occurred in the renal bed. Propranolol blocked the inotropic and beta2 dilator responses while vasoconstricting effects mediated by alpha adrenergic stimulation remained in each of the beds studied. When dobutamine was infused after a combination of practolol and phentolamine, dilatation occurred in each of the beds studied. These observations indicate that dobutamine is a potent positive inotropic agent with relatively slight effects on preload, afterload, or heart rate, and thus may be a potentially useful clinical agent. The one property of this drug which is not ideal is its tendency to cause a redistribution of cardiac output favoring the muscular beds at the expense of the kidney and visceral beds. Images PMID:4825224

Vatner, Stephen F.; McRitchie, Robert J.; Braunwald, Eugene

1974-01-01

92

Relation of Natriuretic Peptides and Midregional Proadrenomedullin to Cardiac Chamber Volumes by Computed Tomography in Patients without Heart Failure: From the ROMICAT Trial  

PubMed Central

BACKGROUND Stress myocyte biomarkers are used prognostically in patients with cardiovascular disease. We examined associations between amino-terminal pro–B-type natriuretic peptide (NT-proBNP), midregional pro–A-type natriuretic peptide (MR-proANP), and midregional proadrenomedullin (MR-proADM) concentrations and cardiac chamber volumes in chest pain patients without heart failure by use of computed tomography (CT). METHODS At the time of 64-slice CT scan, we acquired plasma and serum samples for these biomarkers from 346 patients [mean (SD) age 53 (12) years, 65% men]. Left atrial volume (LAV) and left ventricular volumes at end-diastole (LVEDV) and end-systole (LVESV) were measured and indexed to body surface area (LAVI, LVEDI, LVESI). RESULTS Concentrations of both natriuretic peptides were correlated with LAV and LAVI (r=0.19–0.32, all P ? 0.0005) and MR-proADM with LV volumes and indices (r=?0.14 to ?0.21, all P ? 0.01). NT-proBNP and MR-proANP concentrations were higher in the top quartiles of patients than the lowest quartiles using LAV and LAVI, whereas MR-proADM concentrations were lower in the top quartiles of LV measures. In adjusted analyses, patients had 2- to 4-fold increased risk of LA enlargement for every incremental increase in log10NT-proBNP [LAV odds ratio (OR) 2.4, P = 0.03; LAVI OR 4.0, P = 0.003] and 10- to 13-fold increased risk of LA enlargement for every incremental increase in log10MR-proANP (LAV OR 10.7, P = 0.009; LAVI OR 13.1, P = 0.004). CONCLUSIONS In patients without heart failure, both NT-proBNP and MR-proANP concentrations are independently associated with LA enlargement, whereas MR-proADM concentrations are correlated with LV volumes. This may partially explain the well-recognized value of natriuretic peptides for use in risk stratification. PMID:20185624

Truong, Quynh A.; Siegel, Emily; Karakas, Mahir; Januzzi, James L.; Bamberg, Fabian; Mahabadi, Amir A.; Dasdemir, Selcuk; Brady, Thomas J.; Bergmann, Andreas; Kunde, Jan; Nagurney, John T.; Hoffmann, Udo; Koenig, Wolfgang

2010-01-01

93

Cardiac Imaging in a Patient with Anomalous Origin of the Left Coronary Artery from the Pulmonary ArteryA Case Report  

Microsoft Academic Search

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

Ryosuke Noda; Hisataka Sasao; Michifumi Kyuma; Yoshihiko Ichikawa; Tohru Hasegawa; Akita Endo; Hiroshi Oimatsu; Takehito Takada

2001-01-01

94

A comparison of left ventricular mass between two-dimensional echocardiography, using fundamental and tissue harmonic imaging, and cardiac MRI in patients with hypertension  

Microsoft Academic Search

Purpose: To compare left ventricular mass (LVM) as measured by two-dimensional (2D) echocardiography using two different calculation methods: truncated ellipse (TE) and area length (AL), in both fundamental and tissue harmonic imaging frequencies, to LVM as measured by, the current gold standard, cardiac magnetic resonance imaging (MRI). Turbo gradient echo (TGE) pulse sequence was utilized for MRI. Materials and methods:

Khaled Alfakih; Tim Bloomer; Samantha Bainbridge; Gavin Bainbridge; John Ridgway; Gordon Williams; Mohan Sivananthan

2004-01-01

95

Loss of Opposite Left Ventricular Basal and Apical Rotation Predicts Acute Response to Cardiac Resynchronization Therapy and is Associated With Long-Term Reversed Remodeling  

Microsoft Academic Search

BackgroundNormal left ventricular (LV) torsion is caused by opposite basal and apical rotation. Opposite rotation can be lost in heart failure, but might be restored by pacing; therefore, the predictive value of the loss of opposite base-apex rotation in heart failure patients for the response to cardiac resynchronization therapy (CRT) was studied.

Iris K. Rüssel; Marco J. W. Götte; Gerben J. de Roest; J. Tim Marcus; Sandra R. Tecelão; Cornelis P. Allaart; Carel C. de Cock; Robert M. Heethaar; Albert C. van Rossum

2009-01-01

96

Management of high-risk patients with hypertension and left ventricular hypertrophy in Germany: differences between cardiac specialists in the inpatient and outpatient setting  

Microsoft Academic Search

BACKGROUND: Among patients with hypertension, those with established left ventricular hypertrophy (LVH) represent a high risk cohort with poor prognosis. We aimed to investigate differences in characteristics and health care management of such patients treated as inpatients or outpatients by cardiac specialists. METHODS: Prospective cross-sectional study in patients with hypertension and LVH who were referred to either inpatient care (rehabilitation

Heinz Völler; Frank J Sonntag; Joachim Thiery; Karl Wegscheider; Friedrich C Luft; Kurt Bestehorn

2006-01-01

97

Comparison of Echocardiographic and Cardiac Magnetic Resonance Imaging in Hypertrophic Cardiomyopathy Sarcomere Mutation Carriers Without Left Ventricular Hypertrophy  

PubMed Central

Background Left ventricular hypertrophy (LVH) typically manifests during or after adolescence in sarcomere mutation carriers at risk for developing hypertrophic cardiomyopathy. Guidelines recommend serial imaging of mutation carriers without LVH (G+/LVH?) to monitor for phenotypic evolution, but the optimal strategy is undefined. Compared with echocardiography (echo), cardiac MRI (CMR) offers improved endocardial visualization and potential to assess scar. However, the incremental advantage offered by CMR for early diagnosis of hypertrophic cardiomyopathy is unclear. Therefore, we systematically compared echo and CMR in G+/LVH? subjects. Methods and Results A total of 40 sarcomere mutation carriers with normal echo wall thickness (<12 mm or z score <2.5 in children) underwent concurrent CMR. Mean age was 21.7±11.1 years, 55% were female. If left ventricular wall thickness seemed nonuniform, the size and location of relatively thickened segments were noted. Late gadolinium enhancement was assessed with CMR. Diagnostic agreement between echo and CMR was good (90%), although CMR measurements of left ventricular wall thickness were ?19% lower than echo. Four subjects had mild hypertrophy (12.6–14 mm; ?2 segments) appreciated by CMR but not echo. No subjects had late gadolinium enhancement. During median 35-month follow-up, 2 subjects developed overt hypertrophic cardiomyopathy, including 1 with mild LVH by CMR at baseline. Conclusions Echo is unlikely to miss substantial LVH; however, CMR identified mild hypertrophy in ?10% of mutation carriers with normal echo wall thickness. CMR may be a useful adjunct in hypertrophic cardiomyopathy family screening, particularly in higher risk situations, or if echocardiographic images are suboptimal or suggest borderline LVH. PMID:23690394

Valente, Anne Marie; Lakdawala, Neal K.; Powell, Andrew J.; Evans, Sarah P.; Cirino, Allison L.; Orav, E. John.; MacRae, Calum A.; Colan, Steven D.; Ho, Carolyn Y.

2014-01-01

98

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

99

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

100

Sudden Cardiac Arrest with Acute Myocardial Infarction Induced by Left Subclavian Artery Occlusion in a Patient with Prior Coronary Artery Bypass Surgery  

PubMed Central

Multivascular preventive and therapeutic approaches are necessary in patients with coronary artery disease because atherosclerosis has a common systemic pathogenesis. We present a rare case of sudden cardiac arrest with acute myocardial infarction induced by the total occlusion of left subclavian artery (LSCA) in a patient with a history of previous coronary artery bypass surgery using the left internal mammary artery. We initially performed blind-puncture of left brachial artery, attempting percutaneous coronary intervention because pulses were absent in both upper and lower extremities. However, the cause of sudden cardiac arrest was atherosclerotic total occlusion of LSCA. The patient was stabilized after successful revascularization of LSCA by percutaneous transluminal angioplasty with stent insertion. PMID:23323128

Won, Ki-Bum; Cho, Yun-Hyeong

2012-01-01

101

Does left ventricular tissue Doppler peak systolic velocity (Sm) reflect cardiac output in the critically ill?  

PubMed

Cardiac output (CO) is dependent on a number of factors, in particular, the systolic function of the heart. Tissue Doppler (TD) is a modality in echocardiography that measures myocardial velocity and is related to contractility. TD can therefore be used to measure the systolic function of the heart. This study sought to establish whether the systolic component of TD can be used to estimate CO in critically ill patients. Retrospective data was obtained from a total of 80 patients: 29 patients with a normal echocardiogram, and 51 intensive care unit patients; 28 septic and 23 with heart failure. The mean TD peak systolic velocity (Sm) was significantly lower in the heart failure patients (P <0.05) compared to both normal and septic group. The mean CO was significantly higher in septic patients when compared to heart failure patients. A mild to moderate positive correlation was found between Sm and CO in the heart failure group and with all patients combined (r2=0.19, P <0.001). Subsequent analysis of Sm versus stroke volume again showed a mild positive correlation in the heart failure group and combined results (r2=0.18, P <0.001). Sm was weakly correlated to heart rate only in the normal group but not in the combined cohort. Our data confirms a weak to moderate correlation between Sm and CO, probably resulting from a positive correlation of Sm and stroke volume. This correlation is not strong enough to support the use of an individual's Sm to estimate CO in intensive care patients. PMID:23808508

Golowenko, A R; Nalos, M; Huang, S J

2013-07-01

102

Quantification of the temporal component of left ventricular asynergy by gated cardiac blood pool scans  

SciTech Connect

Fourier analysis (F) has demonstrated that left ventricular (LV) dysfunction can be analyzed in two separate component: an amplitude (AM) and a temporal (T) component. Although the former dominates in hypokinesis and akinesis, and the latter in dyskinesis, they are almost always associated and combine to determine the clinical form of asynergy (AS). The mechanical consequences of the T component cannot be assessed continuously by F which requires setting of a threshold. In this study, the authors have analyzed the potential of a new index; the stroke volume efficiency (SV Eff) to evaluate the importance of T AS in patients (pts) with coronary artery disease studied by gated blood pool scans. The authors have studied 14 controls, 8 pts with coronary artery disease without infarction, 56 pts with myocardial infarction (MI) and 21 pts with LV aneurysm. The SV Eff was calculated as follows after normalization and smoothing of the series: maximum and minimum images were created first and a LV region of interest was traced using the F AM image. The SV Eff ratio was calculated within the LV region of interest as ''diastolic counts - systolic counts/maximum counts - minimum counts''. The SV Eff in controls was 94% +- 2. The authors conclude that SV Eff provides a quantitative measurement of T component of LV dysfunction and an estimate of the dyskinetic component in pts with LV aneurysm. It should prove useful to study these patients serially.

Solot, G.; Chevigne, M.; Rigo, P.

1985-05-01

103

Accurate segmentation framework for the left ventricle wall from cardiac cine MRI  

NASA Astrophysics Data System (ADS)

We propose a novel, fast, robust, bi-directional coupled parametric deformable model to segment the left ventricle (LV) wall borders using first- and second-order visual appearance features. These features are embedded in a new stochastic external force that preserves the topology of LV wall to track the evolution of the parametric deformable models control points. To accurately estimate the marginal density of each deformable model control point, the empirical marginal grey level distributions (first-order appearance) inside and outside the boundary of the deformable model are modeled with adaptive linear combinations of discrete Gaussians (LCDG). The second order visual appearance of the LV wall is accurately modeled with a new rotationally invariant second-order Markov-Gibbs random field (MGRF). We tested the proposed segmentation approach on 15 data sets in 6 infarction patients using the Dice similarity coefficient (DSC) and the average distance (AD) between the ground truth and automated segmentation contours. Our approach achieves a mean DSC value of 0.926+/-0.022 and AD value of 2.16+/-0.60 compared to two other level set methods that achieve 0.904+/-0.033 and 0.885+/-0.02 for DSC; and 2.86+/-1.35 and 5.72+/-4.70 for AD, respectively.

Sliman, H.; Khalifa, F.; Elnakib, A.; Soliman, A.; Beache, G. M.; Gimel'farb, G.; Emam, A.; Elmaghraby, A.; El-Baz, A.

2013-10-01

104

Double left ventricular pacing following accidental malpositioning of the right ventricular electrode during implantation of a cardiac resynchronization therapy device.  

PubMed

Accidental malpositioning of a right ventricular (RV) electrode has not been previously reported in the context of cardiac resynchronization therapy (CRT).The case of a 75-year old male patient with dilative cardiomyopathy, left ventricular (LV) ejection fraction 23%, New York Heart Association functional heart failure status stage III, left bundle branch block (LBBB) with QRS width of 136 ms, and misplacement of the RV lead to the LV apex during implantation of a CRT defibrillator is described.Following unremarkable implantation, routine interrogation of the CRT device on the first day after the implantation revealed uneventful technical findings. The 12-lead surface electrocardiogram (ECG) showed biventricular stimulation featuring a narrow QRS complex with incomplete right bundle branch block (RBBB) and R>S in V1. The biplane postoperative chest X-ray was graded normal. On routine follow-up one month later, a transthoracic echocardiogram revealed an increased ejection fraction of 51% but the RV lead was placed in the LV apex. An additional transesophageal echocardiogram exhibited an Eustachian valve guiding the lead via the patent foramen ovale through the mitral valve into the LV apex. Operative revision was scheduled and the active fixation lead was uneventful removed from the LV. A new electrode was inserted and placed in the RV apex.Accidental malplacement of the RV electrode to the LV may be difficult to diagnose in the context of CRT patients as a stimulated biventricular ECG with incomplete RBBB appearance is expected in this situation. Careful analysis of lateral radiographic views during the operation is important to ensure correct lead positioning. As timely revision is the preferred procedure, early routine transthoracic echocardiography may be considered for detection of malplacement. PMID:23806123

Dissmann, Ruediger; Wolthoff, Udo; Zabel, Markus

2013-01-01

105

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

106

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. PMID:24367544

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

2013-01-01

107

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. PMID:24868514

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

2014-01-01

108

Off-pump coronary artery bypass grafting for a left main lesion due to cardiac allograft vasculopathy in Japan: first report of a case.  

PubMed

Cardiac allograft vasculopathy (CAV) is a major cause of mortality after transplantation. We treated a 44-year-old female with off-pump coronary artery bypass grafting (OPCAB) 4 years after heart transplantation. Annual examinations, including coronary angiography and intravenous ultrasound (IVUS), revealed a severe lesion in the left main trunk. The left internal mammary artery was successfully anastomosed to the left anterior descending artery in an off-pump manner. To ensure that patients have a good long-term outcome after heart transplantation, routine examinations, including IVUS, are crucial, because of the nature of CAV. OPCAB is a good option for a left main trunk lesion due to CAV. PMID:23821318

Fujita, Tomoyuki; Kobayashi, Junjiro; Hata, Hiroki; Murata, Yoshihiro; Seguchi, Osamu; Yanase, Masanobu; Shimahara, Yusuke; Sato, Shunsuke; Nakatani, Takeshi

2014-10-01

109

What is the Lowest Value of Left Ventricular Baseline Ejection Fraction that Predicts Response to Cardiac Resynchronization Therapy?  

PubMed Central

Background Cardiac resynchronization therapy (CRT) is an effective treatment option for patients with refractory heart failure. However, many patients do not respond to therapy. Although it has been thought that there was no relation between response to CRT and baseline ejection fraction (EF), the response rate of patients with different baseline LVEF to CRT has not been evaluated in severe left ventricular systolic dysfunction. We aimed to investigate any difference in response to CRT between the severe heart failure patients with different baseline LVEF. Material/Methods In this study, 141 consecutive patients (mean age 59±13 years; 89 men) with severe heart failure and complete LBBB were included. Patients were divided into 3 groups according to their baseline LVEF: 5–15%, Group 1; 15–25%, Group 2, and 25–35%, Group 3. NYHA functional class, LVEF, LV volumes, and diameters were assessed at baseline and after 6 months of CRT. A response to CRT was defined as a decrease in LVSVi (left ventricular end-systolic volume index) ?10% on echocardiography at 6 months. Results After 6 months, a significant increase of EF and a significant decrease of LVESVi and LVEDVi after 6 months of CRT were observed in all groups. Although the magnitude of improvement in EF was biggest in the first group, the percentage of decrease in LVESVi and LVEDVi was similar between the groups. The improvement in NYHA functional class was similar in all EF subgroups. At 6-month follow-up, 100 (71%) patients showed a reduction of >10% in LVESVi (mean reduction: ?15.5±26.1 ml/m2) and were therefore classified as responders to CRT. Response rate to CRT was similar in all groups. It was 67%, 75%, and 70% in Group 1, 2, and 3, respectively, at 6-month follow-up (p>0.05). There was no statistically significant relation between the response rate to CRT and baseline LVEF, showing that the CRT has beneficial effects even in patients with very low LVEF. Conclusions It seems there is no lower limit for baseline LVEF to predict non-response to CRT in eligible patients according to current guidelines. PMID:25218410

Agir, Aysen Agacdiken; Celikyurt, Umut; Sahin, Tayfun; Yilmaz, Irem; Karauzum, Kurtulus; Bozyel, Serdar; Ural, Dilek; Vural, Ahmet

2014-01-01

110

Cardiac steatosis and left ventricular hypertrophy in patients with generalized lipodystrophy as determined by magnetic resonance spectroscopy and imaging.  

PubMed

Generalized lipodystrophy is a rare disorder characterized by marked loss of adipose tissue with reduced triglyceride storage capacity, leading to a severe form of metabolic syndrome including hypertriglyceridemia, insulin resistance, type 2 diabetes mellitus, and hepatic steatosis. Recent echocardiographic studies suggest that concentric left ventricular (LV) hypertrophy is another characteristic feature of this syndrome, but the mechanism remains unknown. It has recently been hypothesized that the LV hypertrophy could be an extreme clinical example of "lipotoxic cardiomyopathy": excessive myocyte accumulation of triglyceride leading to adverse hypertrophic signaling. To test this hypothesis, the first cardiac magnetic resonance study of patients with generalized lipodystrophy was performed, using magnetic resonance imaging and localized proton spectroscopy to detect excessive triglyceride content in the hypertrophied myocytes. Six patients with generalized lipodystrophy and 6 healthy controls matched for age, gender, and body mass index were studied. As hypothesized, myocardial triglyceride content was threefold higher in patients than controls: 0.6 ± 0.2% versus 0.2 ± 0.1% (p = 0.004). The presence of pericardial fat was also found, representing a previously undescribed adipose depot in generalized lipodystrophy. Patients with generalized lipodystrophy, compared with controls, also had a striking degree of concentric LV hypertrophy, independent of blood pressure: LV mass index 101.0 ± 18.3 versus 69.0 ± 17.7 g/m(2), respectively (p = 0.02), and LV concentricity 1.3 ± 0.3 versus 0.99 ± 0.1 g/ml, respectively (p = 0.04). In conclusion, these findings advance the lipotoxicity hypothesis as a putative underlying mechanism for the dramatic concentric LV hypertrophy found in generalized lipodystrophy. PMID:23800548

Nelson, Michael D; Victor, Ronald G; Szczepaniak, Edward W; Simha, Vinaya; Garg, Abhimanyu; Szczepaniak, Lidia S

2013-10-01

111

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

112

Conduction Patterns in the Cardiac Veins: Electrophysiologic Characteristics of the Connections Between Left Atrial and Coronary Sinus Musculature  

Microsoft Academic Search

Introduction: Fractionated electrograms and double potentials have been well described within the coronary sinus (CS) in humans. The pattern of circumferential activation in the CS has not been investigated. Furthermore, no data exist on conduction characteristics within the great cardiac vein (GCV) or the middle cardiac vein (MCV).

Demosthenes G. Katritsis; Eleftherios Giazitzoglou; Socrates Korovesis; Evangelia Karvouni; Constantine E. Anagnostopoulos; A. John Camm

2004-01-01

113

Predictive Value of Beat-to-Beat QT Variability Index across the Continuum of Left Ventricular Dysfunction: Competing Risks of Non-cardiac or Cardiovascular Death, and Sudden or Non-Sudden Cardiac Death  

PubMed Central

Background The goal of this study was to determine the predictive value of beat-to-beat QT variability in heart failure (HF) patients across the continuum of left ventricular dysfunction. Methods and Results Beat-to-beat QT variability index (QTVI), heart rate variance (LogHRV), normalized QT variance (QTVN), and coherence between heart rate variability and QT variability have been measured at rest during sinus rhythm in 533 participants of the Muerte Subita en Insuficiencia Cardiaca (MUSIC) HF study (mean age 63.1±11.7; males 70.6%; LVEF >35% in 254 [48%]) and in 181 healthy participants from the Intercity Digital Electrocardiogram Alliance (IDEAL) database. During a median of 3.7 years of follow-up, 116 patients died, 52 from sudden cardiac death (SCD). In multivariate competing risk analyses, the highest QTVI quartile was associated with cardiovascular death [hazard ratio (HR) 1.67(95%CI 1.14-2.47), P=0.009] and in particular with non-sudden cardiac death [HR 2.91(1.69-5.01), P<0.001]. Elevated QTVI separated 97.5% of healthy individuals from subjects at risk for cardiovascular [HR 1.57(1.04-2.35), P=0.031], and non-sudden cardiac death in multivariate competing risk model [HR 2.58(1.13-3.78), P=0.001]. No interaction between QTVI and LVEF was found. QTVI predicted neither non-cardiac death (P=0.546) nor SCD (P=0.945). Decreased heart rate variability (HRV) rather than increased QT variability was the reason for increased QTVI in this study. Conclusions Increased QTVI due to depressed HRV predicts cardiovascular mortality and non-sudden cardiac death, but neither SCD nor excracardiac mortality in HF across the continuum of left ventricular dysfunction. Abnormally augmented QTVI separates 97.5% of healthy individuals from HF patients at risk. PMID:22730411

Tereshchenko, Larisa G.; Cygankiewicz, Iwona; McNitt, Scott; Vazquez, Rafael; Bayes-Genis, Antoni; Han, Lichy; Sur, Sanjoli; Couderc, Jean-Philippe; Berger, Ronald D.; de Luna, Antoni Bayes; Zareba, Wojciech

2012-01-01

114

A Comprehensive Analysis of Cardiac Dose in Balloon-Based High-Dose-Rate Brachytherapy for Left-Sided Breast Cancer  

SciTech Connect

Purpose: To investigate radiation dose to the heart in 60 patients with left-sided breast cancer who were treated with balloon-based high-dose-rate brachytherapy using MammoSite or Contura applicators. Methods and Materials: We studied 60 consecutive women with breast cancer who were treated with 34 Gy in 10 twice-daily fractions using MammoSite (n = 37) or Contura (n = 23) applicators. The whole heart and the left and right ventricles were retrospectively delineated, and dose-volume histograms were analyzed. Multiple dosimetrics were reported, such as mean dose (D{sub mean}); relative volume receiving 1.7, 5, 10, and 20 Gy (V1.7, V5, V10, and V20, respectively); dose to 1 cc (D{sub 1cc}); and maximum point dose (D{sub max}). Biologic metrics, biologically effective dose and generalized equivalent uniform dose were computed. The impact of lumpectomy cavity location on cardiac dose was investigated. Results: The average {+-} standard deviation of D{sub mean} was 2.45 {+-} 0.94 Gy (range, 0.56-4.68) and 3.29 {+-} 1.28 Gy (range, 0.77-6.35) for the heart and the ventricles, respectively. The average whole heart V5 and V10 values were 10.2% and 1.3%, respectively, and the heart D{sub max} was >20 Gy in 7 of 60 (11.7%) patients and >25 Gy in 3 of 60 (5%) patients. No cardiac tissue received {>=}30 Gy. The V1.7, V5, V10, V20, and D{sub mean} values were all higher for the ventricles than for the whole heart. For balloons located in the upper inner quadrant of the breast, the average whole heart D{sub mean} was highest. The D{sub mean}, biologically effective dose, and generalized equivalent uniform dose values for heart and ventricles decreased with increasing minimal distance from the surface of the balloon. Conclusions: On the basis of these comprehensive cardiac dosimetric data, we recommend that cardiac dose be routinely reported and kept as low as possible in balloon-based high-dose-rate brachytherapy treatment planning for patients with left-sided breast cancer so the correlation with future cardiac toxicity data can be investigated.

Valakh, Vladimir, E-mail: vladimir@valakh.com [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Kim, Yongbok; Werts, E. Day; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, PA (United States); Drexel University College of Medicine, Allegheny Campus, Pittsburgh, PA (United States)

2012-04-01

115

3D left ventricular extracellular volume fraction by low-radiation dose cardiac CT: Assessment of interstitial myocardial fibrosis  

PubMed Central

Background Myocardial fibrosis leads to impaired cardiac function and events. Extracellular volume fraction (ECV) assessed with an iodinated contrast agent and measured by cardiac CT may be a useful noninvasive marker of fibrosis. Objective The purpose of this study was to develop and evaluate a 3-dimensional (3D) ECV calculation toolkit (ECVTK) for ECV determination by cardiac CT. Methods Twenty-four subjects (10 systolic heart failure, age, 60 ± 17 years; 5 diastolic failure, age 56 ± 20 years; 9 matched healthy subjects, age 59 ± 7 years) were evaluated. Cardiac CT examinations were done on a 320-multidetector CT scanner before and after 130 mL of iopamidol (Isovue-370; Bracco Diagnostics, Plainsboro, NJ, USA) was administered. A calcium score type sequence was performed before and 7 minutes after contrast with single gantry rotation during 1 breath hold and single cardiac phase acquisition. ECV was calculated as (?HUmyocardium/?HUblood) × (1 ? Hct) where Hct is the hematocrit, and ?HU is the change in Hounsfield unit attenuation = HUafter iodine ? HUbefore iodine. Cardiac magnetic resonance imaging was performed to assess myocardial structure and function. Results Mean 3D ECV values were significantly higher in the subjects with systolic heart failure than in healthy subjects and subjects with diastolic heart failure (mean, 41% ± 6%, 33% ± 2%, and 35% ± 5%, respectively; P = 0.02). Interobserver and intraobserver agreements were excellent for myocardial, blood pool, and ECV (intraclass correlation coefficient, >0.90 for all). Higher 3D ECV by cardiac CT was associated with reduced systolic circumferential strain, greater end-diastolic and -systolic volumes, and lower ejection fraction (r = 0.70, r = 0.60, r = 0.73, and r = ?0.68, respectively; all P < 0.001). Conclusion 3D ECV by cardiac CT can be performed with ECVTK. We demonstrated increased ECV in subjects with systolic heart failure compared with healthy subjects. Cardiac CT results also showed good correlation with important functional heart biomarkers, suggesting the potential for myocardial tissue characterization with the use of 3D ECV by cardiac CT. This trial is registered at www.ClinicalTrials.gov as NCT01160471. PMID:23333188

Nacif, Marcelo Souto; Liu, Yixun; Yao, Jianhua; Liu, Songtao; Sibley, Christopher T.; Summers, Ronald M.; Bluemke, David A.

2014-01-01

116

Impact of left ventricular lead position on the incidence of ventricular arrhythmia and clinical outcome in patients with cardiac resynchronization therapy  

Microsoft Academic Search

Purpose  The aim of the study was to evaluate the incidence of ventricular arrhythmia and clinical outcome in patients receiving a\\u000a cardiac resynchronization therapy (CRT) depending on the left ventricular (LV) lead position.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A total of 187 consecutive patients with advanced heart failure who received a CRT-implantable cardioverter defibrillator\\u000a were analyzed. Forty patients (21%) had a LV lead in the anterior\\/apical

Thomas Kleemann; Torsten Becker; Margit Strauss; Ngoc Dyck; Steffen Schneider; Udo Weisse; Werner Saggau; Bernd Cornelius; Günter Layer; Karlheinz Seidl

2010-01-01

117

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

118

Atrial high rate episodes in patients with dual-chamber cardiac implantable electronic devices: unmasking silent atrial fibrillation.  

PubMed

Assessment of the prevalence of silent paroxysmal atrial fibrillation (AF) represents a challenge, since the arrhythmia may be brief, completely asymptomatic, and difficult to detect. Lack of symptoms from AF should not be equated to lack of risk of thromboembolic complications. Today's cardiac implantable electronic devices (CIED) diagnostics include system diagnostics accurately revealing asymptomatic cardiac arrhythmias as atrial high rate episodes (AHRE). The presence of AHRE has been related to increased risk of stroke and systemic embolism. The application of anticoagulation therapy in patients with device-detected AHRE is yet unclear and challenging in the absence of randomized studies. Until further studies are available, anticoagulation therapy should be individualized and promoted attending to the CHADS2 score. Future guidelines should deal with this peculiar AF scenario to make professionals who routinely perform CIED follow-ups aware of these relevant episodes and their clinical implications. PMID:24888216

Benezet-Mazuecos, Juan; Rubio, José Manuel; Farré, Jerónimo

2014-08-01

119

Left lower lobe atelectasis and consolidation following cardiac surgery: the effect of topical cooling on the phrenic nerve  

SciTech Connect

Retrospective and prospective analyses of chest radiographs of patients following coronary artery bypass surgery were undertaken. Left lower lobe pulmonary infiltrate and/or atelectasis developed in 13 of 40 (32.5%) patients who were operated upon without topical cooling of the heart with ice, and in 77 of 122 (63.1%) patients in one group and 34 of 40 (85.0%) patients in another group who were operated upon with topical cooling of the heart with ice. This difference was highly significant (p<0.001). Of the patients in one group in whom left lower lobe abnormality developed, 69.2% had paralysis or paresis of the left hemidiaphragm. It is evident that application of ice to the phrenic nerve can lead to temporary paralysis of the left leaf of the diaphragm, with subsequent development of left lower lobe pulmonary infiltrate and/or atelectasis.

Benjamin, J.J.; Cascade, P.N.; Rubenfire, M.; Wajszczuk, W.; Kerin, N.Z.

1982-01-01

120

Double inlet left ventricle  

MedlinePLUS

... born with this condition have only one working pumping chamber (ventricle) in their heart. ... condition generally have a large left ventricle (the pumping chamber of the heart that supplies the body ...

121

A Rare Case of Congenital Heart Disease with Bifid Cardiac Apex: A Unique Finding in Left Ventricle  

PubMed Central

Bifid cardiac apex is a rare anomaly of human hearts. We report of the case of a 34-year-old man with a previous history of ventricular septal defect (VSD) and subvalvular pulmonary stenosis. He had undergone pulmonary commissurotomy and VSD closure 22 years before he was referred to our center for evaluation of progressive dyspnea. Transthoracic echocardiography revealed atrial septal defect (ASD), multiple VSDs, severe pulmonary regurgitation, and a bifid cardiac apex. The patient was referred for re-do surgery for ASD and VSD closure along with pulmonary valve replacement, but he refused the surgery. PMID:24396366

Maleki, Majid; Esmaeilzadeh, Maryam; Alizadeasl, Azin; Hashemi, Arash

2013-01-01

122

The number of cardiac myocytes in the hypertrophic and hypotrophic left ventricle of the obese and calorie-restricted mouse heart.  

PubMed

Changes in body mass due to varying amounts of calorie intake occur frequently with obesity and anorexia/cachexia being at opposite sides of the scale. Here, we tested whether a high-fat diet or calorie restriction (CR) decreases the number of cardiac myocytes and affects their volume. Ten 6-8-week-old mice were randomly assigned to a normal (control group, n?=?5) or high-fat diet (obesity group, n?=?5) for 28?weeks. Ten 8-week-old mice were randomly assigned to a normal (control group, n?=?5) or CR diet (CR group, n?=?5) for 7?days. The left ventricles of the hearts were prepared for light and electron microscopy, and analysed by design-based stereology. In CR, neither the number of cardiac myocytes, the relationship between one- and multinucleate myocytes nor their mean volume were significantly different between the groups. In contrast, in the obese mice we observed a significant increase in cell size combined with a lower number of cardiomyocytes (P?cardiac myocyte reflected the hypertrophic and hypotrophic remodelling in obesity and CR, respectively, but were only significant in the obese mice, indicating a more profound effect of the obesity protocol than in the CR experiments. Taken together, our data indicate that long-lasting obesity is associated with a loss of cardiomyocytes of the left ventricle, but that short-term CR does not alter the number of cardiomyocytes. PMID:25322944

Schipke, Julia; Banmann, Ewgenija; Nikam, Sandeep; Voswinckel, Robert; Kohlstedt, Karin; Loot, Annemarieke E; Fleming, Ingrid; Mühlfeld, Christian

2014-11-01

123

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

124

N-Terminal Pro-B-Type Natriuretic Peptide Plasma Levels as a Potential Biomarker for Cardiac Damage After Radiotherapy in Patients With Left-Sided Breast Cancer  

SciTech Connect

Purpose: Adjuvant radiotherapy (RT) after breast-conserving surgery has been associated with increased cardiovascular mortality. Cardiac biomarkers may aid in identifying patients with radiation-mediated cardiac dysfunction. We evaluated the correlation between N-terminal pro-B-type natriuretic peptide (NT-proBNP) and troponin (TnI) and the dose of radiation to the heart in patients with left-sided breast cancer. Methods and Materials: NT-proBNP and TnI plasma concentrations were measured in 30 left-sided breast cancer patients (median age, 55.0 years) 5 to 22 months after RT (Group I) and in 30 left-sided breast cancer patients (median age, 57.0 years) before RT as control group (Group II). Dosimetric and geometric parameters of heart and left ventricle were determined in all patients of Group I. Seventeen patients underwent complete two-dimensional echocardiography. Results: NT-proBNP levels were significantly higher (p = 0.03) in Group I (median, 90.0 pg/ml; range, 16.7-333.1 pg/ml) than in Group II (median, 63.2 pg/ml; range, 11.0-172.5 pg/ml). TnI levels remained below the cutoff threshold of 0.07 ng/ml in both groups. In patients with NT-proBNP values above the upper limit of 125 pg/ml, there were significant correlations between plasma levels and V{sub 3Gy}(%) (p = 0.001), the ratios D{sub 15cm{sup 3}}(Gy)/D{sub mean}(Gy) (p = 0.01), the ratios D{sub 15cm}{sup 3}/D{sub 50%} (Gy) (p = 0.008) for the heart and correlations between plasma levels and V{sub 2Gy} (%) (p = 0.002), the ratios D{sub 1cm{sup 3}}(Gy)/D{sub mean}(Gy) (p = 0.03), and the ratios D{sub 0.5cm{sup 3}}(Gy)/D{sub 50%}(Gy) (p = 0.05) for the ventricle. Conclusions: Patients with left-sided breast cancer show higher values of NT-pro BNP after RT when compared with non-RT-treated matched patients, increasing in correlation with high doses in small volumes of heart and ventricle. The findings of this study show that the most important parameters are not the mean doses but instead the small percentage of organ volumes (heart or ventricle) receiving high dose levels, supporting the notion that the heart behaves as a serial organ.

D'Errico, Maria P., E-mail: patderrico@libero.it [Department of Laboratory Medicine, 'A. Perrino' Hospital, Brindisi (Italy); Grimaldi, Luca [Department of Medical Physics, 'A. Perrino' Hospital, Brindisi (Italy); Petruzzelli, Maria F. [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Gianicolo, Emilio A.L. [Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy); Tramacere, Francesco [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Monetti, Antonio; Placella, Roberto [Department of Laboratory Medicine, 'A. Perrino' Hospital, Brindisi (Italy); Pili, Giorgio [Department of Medical Physics, 'A. Perrino' Hospital, Brindisi (Italy); Andreassi, Maria Grazia; Sicari, Rosa; Picano, Eugenio [Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy); Portaluri, Maurizio [Department of Radiation Oncology, 'A. Perrino' Hospital, Brindisi (Italy); Clinical Physiology Institute, National Research Council (IFC-CNR), Pisa-Lecce (Italy)

2012-02-01

125

A Rare Combination of the Left Circumflex Coronary Artery Fistula Connecting a Dilated Coronary Sinus with Persistent Left Superior Vena Cava and Multiple Arteriovenous Fistulae  

PubMed Central

Coronary artery fistula (CAF) is an abnormal communication between an epicardial coronary artery and a cardiac chamber, major vessel or other vascular structures. This report presents a rare case of CAF in which a dilated left main trunk and proximal circumflex coronary artery are connected to a dilated coronary sinus. There were also two other fistulae and persistent left superior vena cava. The coronary fistula was managed conservatively. PMID:23755085

Yeon, Myeong Ho; Choi, Young Rak; Lee, Sang Yeub; Bae, Jang Whan; Hwang, Kyung Kuk; Kim, Dong Woon; Cho, Myeong Chan

2013-01-01

126

Predictors of left ventricular reverse remodeling after cardiac resynchronization therapy for heart failure secondary to idiopathic dilated or ischemic cardiomyopathy  

Microsoft Academic Search

Biventricular pacing results in left ventricular (LV) reverse remodeling in heart failure patients with wide QRS complexes. This study examines potential predictors of reverse remodeling. Echocardiography with tissue Doppler imaging was performed at baseline and 3 months after biventricular pacing in 30 patients (21 men and 9 women, mean age 62 ± 14 years). There were 17 responders to reverse

Cheuk-Man Yu; Wing-Hong Fung; Hong Lin; Qing Zhang; John E Sanderson; Chu-Pak Lau

2003-01-01

127

Anomalous aortic origin of the left coronary artery: in-hospital cardiac arrest and death despite bed rest.  

PubMed

A ten-year-old female was admitted with syncope and a myocardial infarction, was resuscitated, and was diagnosed with anomalous left coronary artery from right aortic sinus. After initial stabilization, she was on bed rest in the intensive care unit awaiting surgery and experienced sudden arrest and could not be resuscitated, resulting in death. PMID:25324257

Law, Whitney; DiBardino, Daniel J; Raviendren, Raveen; Devaney, Eric; Davis, Christopher

2014-10-01

128

Significant left ventricular hypertrophy on SPECT imaging in a patient with hypertrophic cardiomyopathy: a comparative image with cardiac magnetic resonance  

Microsoft Academic Search

Hypertrophic cardiomyopathy (HCM) is a common genetically transmitted disease defined histologically by the presence of myocyte disarray and clinically by the presence of unexplained left ventricular hypertrophy in the absence of hemodynamic stress. 1-3 This disease has a varied clinical course and outcome, with many patients having few or no discernable cardiovascular symptoms whereas others have profound exercise limitation and

Akash Ghai; Evelyn Horn; Gregory Pearson; Sabahat Bokhari

2005-01-01

129

Finite element stress analysis of the human left ventricle whose irregular shape is developed from single plane cineangiocardiogram  

NASA Technical Reports Server (NTRS)

The three-dimensional left ventricular chamber geometrical model is developed from single plane cineangiocardiogram. This left ventricular model is loaded by an internal pressure monitored by cardiac catheterization. The resulting stresses in the left ventricular model chamber's wall are determined by computerized finite element procedure. For the discretization of this left ventricular model structure, a 20-node, isoparametric finite element is employed. The analysis and formulation of the computerised procedure is presented in the paper, along with the detailed algorithms and computer programs. The procedure is applied to determine the stresses in a left ventricle at an instant, during systole. Next, a portion (represented by a finite element) of this left ventricular chamber is simulated as being infarcted by making its active-state modulus value equal to its passive-state value; the neighbouring elements are shown to relieve the 'infarcted' element of stress by themselves taking on more stress.

Ghista, D. N.; Hamid, M. S.

1977-01-01

130

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

PubMed Central

Background Cardiac resynchronization therapy (CRT) is an established treatment in heart failure patients. However, a large proportion of patients remain nonresponsive to this pacing strategy. Left ventricular (LV) lead position is one of the main determinants of response to CRT. This study aims to clarify whether multimodality imaging guided LV lead placement improves clinical outcome after CRT. Methods/Design The ImagingCRT study is a prospective, randomized, patient- and assessor-blinded, two-armed trial. The study is designed to investigate the effect of imaging guided left ventricular lead positioning on a clinical composite primary endpoint comprising all-cause mortality, hospitalization for heart failure, or unchanged or worsened functional capacity (no improvement in New York Heart Association class and <10% improvement in six-minute-walk test). Imaging guided LV lead positioning is targeted to the latest activated non-scarred myocardial region by speckle tracking echocardiography, single-photon emission computed tomography, and cardiac computed tomography. Secondary endpoints include changes in LV dimensions, ejection fraction and dyssynchrony. A total of 192 patients are included in the study. Discussion Despite tremendous advances in knowledge with CRT, the proportion of patients not responding to this treatment has remained stable since the introduction of CRT. ImagingCRT is a prospective, randomized study assessing the clinical and echocardiographic effect of multimodality imaging guided LV lead placement in CRT. The results are expected to make an important contribution in the pursuit of increasing response rate to CRT. Trial registration Clinicaltrials.gov identifier NCT01323686. The trial was registered March 25, 2011 and the first study subject was randomized April 11, 2011. PMID:23782792

2013-01-01

131

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. PMID:22705587

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

132

Effects of tumour necrosis factor-? on left ventricular function in the rat isolated perfused heart: possible mechanisms for a decline in cardiac function  

PubMed Central

The cardiac depressant actions of TNF were investigated in the isolated perfused rat heart under constant flow (10?ml?min?1) and constant pressure (70?mmHg) conditions, using a recirculating (50?ml) mode of perfusion.Under constant flow conditions TNF (20?ng?ml?1) caused an early (<25?min) decrease in left ventricular developed pressure (LVDP), which was maintained for 90?min (LVDP after 90?min: control vs TNF; 110±4 vs 82±10?mmHg, P<0.01).The depression in cardiac function seen with TNF under constant flow conditions, was blocked by the ceramidase inhibitor N-oleoylethanolamine (NOE), 1??M, (LVDP after 90?min: TNF vs TNF with NOE; 82±10 vs 111±5?mmHg, P<0.05).In hearts perfused at constant pressure, TNF caused a decrease in coronary flow rate (change in flow 20?min after TNF: control vs TNF; ?3.0±0.9 vs ?8.7±1.2?ml?min?1, P<0.01). This was paralleled by a negative inotropic effect (change in LVDP 20?min after TNF: control vs TNF; ?17±7 vs ?46±6?mmHg, P<0.01). The decline in function was more rapid and more severe than that seen under conditions of constant flow.These data indicate that cardiac function can be disrupted by TNF on two levels, firstly via a direct, ceramidase dependant negative inotropic effect, and secondly via an indirect coronary vasoconstriction. PMID:10051135

Edmunds, N J; Lal, H; Woodward, B

1999-01-01

133

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

134

Atherosclerotic renal artery stenosis is prevalent in cardiorenal patients but not associated with left ventricular function and myocardial fibrosis as assessed by cardiac magnetic resonance imaging  

PubMed Central

Background Atherosclerotic renal artery stenosis (ARAS) is common in cardiovascular diseases and associated with hypertension, renal dysfunction and/or heart failure. There is a paucity of data about the prevalence and the role of ARAS in the pathophysiology of combined chronic heart failure (CHF) and chronic kidney disease (CKD). We investigated the prevalence in patients with combined CHF/CKD and its association with renal function, cardiac dysfunction and the presence and extent of myocardial fibrosis. Methods The EPOCARES study (ClinTrialsNCT00356733) investigates the role of erythropoietin in anaemic patients with combined CHF/CKD. Eligible subjects underwent combined cardiac magnetic resonance imaging (cMRI), including late gadolinium enhancement, with magnetic resonance angiography of the renal arteries (MRA). Results MR study was performed in 37 patients (median age 74?years, eGFR 37.4?±?15.6?ml/min, left ventricular ejection fraction (LVEF) 43.3?±?11.2%), of which 21 (56.8%) had ARAS (defined as stenosis >50%). Of these 21 subjects, 8 (21.6%) had more severe ARAS >70% and 8 (21.6%) had a bilateral ARAS >50% (or previous bilateral PTA). There were no differences in age, NT-proBNP levels and medication profile between patients with ARAS versus those without. Renal function declined with the severity of ARAS (p?=?0.03), although this was not significantly different between patients with ARAS versus those without. Diabetes mellitus was more prevalent in patients without ARAS (56.3%) against those with ARAS (23.8%) (p?=?0.04). The presence and extent of late gadolinium enhancement, depicting myocardial fibrosis, did not differ (p?=?0.80), nor did end diastolic volume (p?=?0.60), left ventricular mass index (p?=?0.11) or LVEF (p?=?0.15). Neither was there a difference in the presence of an ischemic pattern of late enhancement in patients with ARAS versus those without. Conclusions ARAS is prevalent in combined CHF/CKD and its severity is associated with a decline in renal function. However, its presence does not correlate with a worse LVEF, a higher left ventricular mass or with the presence and extent of myocardial fibrosis. Further research is required for the role of ARAS in the pathophysiology of combined chronic heart and renal failure. PMID:22989293

2012-01-01

135

Pathological findings in cardiac apex removed during implantation of left ventricular assist devices (LVAD) are non-specific: 13-year-experience at a German Heart Center  

PubMed Central

Background and aim: Ventricular assist devices (VAD) have become an established therapy for patients with end-stage heart failure. The two main reasons for this development are the shortage of appropriate donor organs and the increasing number of patients waiting for heart transplantation (HTX). Furthermore, the enormous advances in the technical equipment and the rising clinical experience have improved the implantation technique, the durability and the long-term patient outcomes. Methods: We reviewed all cases of left ventricular assist device (LVAD) implantation at our Erlangen Heart Center during January 2000-July 2013. The main aim of this study was to analyze the underlying pathology from the cardiac apex removed during the implantation. From all patients, we created a follow-up, analyzed the pathological features with the clinical diagnoses and described the overall outcome. Results: VAD implantation was performed in 266 cases at our center in the last 13 years (2.2% of the total of 12254 cardiac surgical operations in that period). From these patients, 223 underwent LVAD or biventricular (BVAD) implantation; the remaining received a right (RVAD) implantation. The most frequent underlying clinical diagnoses were dilated (n = 84, 37.7%, DCM) or ischemic (n = 61, 27.4%, ICM) cardiomyopathy. The pathological findings in the apex biopsy were generally non-specific and showed variable interstitial myocardial fibrosis with evidence of fibre loss, fatty degeneration and variable irregular atrophy of muscle fibres, consistent with dilated and ischemic cardiomyopathies as the most frequent causes of heart failure in these patients. Only a few cases showed other specific features such as myocarditis and AL-amyloidosis. Conclusions: Pathological findings in cardiac apex removed during LVAD implantation are rather non-specific and they generally reflect the late stage or consequences of chronic myocardial damage in cases of dilated or ischemic cardiomyopathies. Variable patchy chronic inflammatory changes may be observed in cardiomyopathies as a non-specific reaction caused by myocardial fiber damage and should not lead to misinterpretation as evidence of myocarditis or revision of original diagnosis. PMID:25337196

Strecker, Thomas; Rosch, Johannes; Weyand, Michael; Agaimy, Abbas

2014-01-01

136

Impact of epoetin alfa on left ventricular structure, function, and pressure volume relations as assessed by cardiac magnetic resonance: the heart failure preserved ejection fraction (HFPEF) anemia trial.  

PubMed

Anemia, a common comorbidity in older adults with heart failure and a preserved ejection fraction (HFPEF), is associated with worse outcomes. The authors quantified the effect of anemia treatment on left ventricular (LV) structure and function as measured by cardiac magnetic resonance (CMR) imaging. A prospective, randomized single-blind clinical trial (NCT NCT00286182) comparing the safety and efficacy of epoetin alfa vs placebo for 24 weeks in which a subgroup (n=22) had cardiac magnetic resonance imaging (MRI) at baseline and after 3 and 6 months to evaluate changes in cardiac structure and function. Pressure volume (PV) indices were derived from MRI measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVAiso), were calculated. Patients (75±10 years, 64% women) with HFPEF (EF=63%±15%) with an average hemoglobin of 10.3±1.1 gm/dL were treated with epoetin alfa using a dose-adjusted algorithm that increased hemoglobin compared with placebo (P<.0001). As compared with baseline, there were no significant changes in end-diastolic (-7±8 mL vs -3±8 mL, P=.81) or end-systolic (-0.4±2 mL vs -0.7±5 mL, P=.96) volumes at 6-month follow-up between epoetin alfa compared with placebo. LV function as measured based on EF (-1.5%±1.6% vs -2.6%±3.3%, P=.91) and pressure volume indices (PVAiso-EDP at 30 mm Hg, -5071±4308 vs -1662±4140, P=.58) did not differ between epoetin alfa and placebo. Administration of epoetin alfa to older adult patients with HFPEF resulted in a significant increase in hemoglobin, without evident change in LV structure, function, or pressure volume relationships as measured quantitatively using CMR imaging. PMID:23517485

Green, Philip; Babu, Benson A; Teruya, Sergio; Helmke, Stephen; Prince, Martin; Maurer, Mathew S

2013-01-01

137

Degree and distribution of left ventricular hypertrophy as a determining factor for elevated natriuretic peptide levels in patients with hypertrophic cardiomyopathy: insights from cardiac magnetic resonance imaging.  

PubMed

Whether the left ventricular (LV) mass index (LVMI) and LV volumetric parameters are associated independently with natriuretic peptide levels is unclear in hypertrophic cardiomyopathy (HCM). Therefore, we investigated which parameters have an independent relationship with N-terminal pro-B type natriuretic peptide (NT-proBNP) levels in HCM patients using echocardiography and cardiac magnetic resonance imaging (CMR). A total of 103 patients with HCM (82 men, age 53 ± 12 years) were evaluated. Echocardiographic evaluations included left atrial volume index (LAVI) and early diastolic mitral inflow E velocity to early annular Ea velocity ratio (E/Ea). LVMI, maximal wall thickness and LV volumetric parameters were measured using CMR. The median value of NT-proBNP level was 387.0 pg/ml. The mean NT-proBNP level in patients with non-apical HCM (n = 69; 36 patients with asymmetric septal hypertrophy, 11 with diffuse, and 22 with mixed type) was significantly higher than in those with apical HCM (n = 34, P < 0.001). NT-proBNP level was negatively correlated with LV end-diastolic volume (LVEDV) (r = -0.263, P = 0.007) and positively with LVMI (r = 0.225, P = 0.022) and maximal wall thickness (r = 0.495, P < 0.001). Among the echocardiographic variables, LAVI (r = 0.492, P < 0.001) and E/Ea (r = 0.432, P < 0.001) were correlated with NT-proBNP. On multivariable analysis, non-apical HCM, increased maximal wall thickness and LAVI were independently related with NT-proBNP. Severity of LV hypertrophy and diastolic parameters might be important in the elevation of NT-proBNP level in HCM. Therefore, further evaluation of these parameters in HCM might be warranted. PMID:21516440

Park, Jeong Rang; Choi, Jin-Oh; Han, Hye Jin; Chang, Sung-A; Park, Sung-Ji; Lee, Sang-Chol; Choe, Yeon Hyeon; Park, Seung Woo; Oh, Jae K

2012-04-01

138

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

139

Off-pump anteroapical aneurysm plication following left ventricular postinfarction aneurysm: effect on cardiac function, clinical status and survival  

PubMed Central

Background In patients with coronary disease and aneurysm, ventricular reconstruction with revascularization is a surgical option. Details of patient selection and optimal surgical technique are still debated. We report our results with off-pump aneurysm plication after ventricular aneurysm with relative wall thinning. Methods We retrospectively reviewed the records of 248 patients who had an operation for postinfarction left ventricular aneurysm. Reconstruction was accomplished by off-pump anteroapical aneurysm plication. The following variables were recorded: preoperative clinical, angiographic and echocardiographic findings and operative procedures. Outcomes were early mortality, long-term survival and poor 5-year result, defined as the need for transplantation or repeated hospitalization for congestive heart failure. Risk factors were pinpointed using the t test and survival curves. Independent risk factors were identified using Cox regression methods. Results Hospital mortality was low (2.0%). Mean follow-up was 5.8 (standard deviation [SD] 3.8) years. Actuarial survival at 1 and 5 years was 94% and 84%. Among the 232 survivors, 200 were in functional class I or II, and the average increase in ejection fraction was 14.0% (SD 3.1%). As determined by multivariable analysis, factors predicting poor outcome were advanced age, ejection fraction less than 0.35, conicity index less than 1, end-systolic volume index greater than 80 mL/m2, advanced New York Heart Association functional class and congestive heart failure. Conclusion Using wall thinning as a criterion for patient selection, the technique of off-pump anteroapical aneurysm plication can be performed with low operative mortality and provides good symptomatic relief and long-term survival. PMID:23351499

Huang, Xin-sheng; Gu, Cheng-xiong; Yang, Jun-feng; Wei, Hua; Li, Jing-xing; Zhou, Qi-wen

2013-01-01

140

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

141

Motor current waveforms as an index for evaluation of native cardiac function during left ventricular support with a centrifugal blood pump.  

PubMed

Control of ventricular assist devices (VADs) for native heart preservation should be attempted, and it could be one strategy for dealing with the shortage of donors in the future. In the application of a nonpulsatile blood pump for ventricular assistance from its apex to the aorta, the bypass flow and hence motor current of the pumps change in response to the ventricular pressure change. Utilizing these intrinsic characteristics of the continuous flow pumps, this study investigated whether or not motor current could be used as an index for continuous monitoring of native cardiac function. In Study 1, a centrifugal blood pump (CFP) VAD was installed between the apex and descending aorta of a mock circulatory loop. In this model, a baseline with a preload of 10 mm Hg, afterload of 40 mm Hg, and left ventricular (LV) systolic pressure of 40 mm Hg was used. The pump rpm were fixed at 1,300, 1,500, and 1,700, and LV systolic pressure was increased up to 140 mm Hg by a step of 20 mm Hg while observing the changes in LV pressure, motor current, pump flow, and aortic pressure. In Study 2, in vivo experiments were performed using 5 sheep. A left heart bypass model was created using a centrifugal pump from the ventricular apex to the descending aorta. The LV pressure was varied through administration of dopamine while observing the changes in LV pressure, pump flow, motor current, and aortic pressure at 1,500 and 1,700 rpm. An excellent correlation was observed both in vitro and in vivo studies in the relationship between motor current and LV pressure. In Study 1, the correlation coefficients were 0.77, 0.92, and 0.99 for 1,300, 1,500, and 1,700 rpm, respectively. In Study 2, they were 0.90 (Animal 1), 0.82 (Animal 2), 0.89 (Animal 3), 0.93 (Animal 4), and 0.70 (Animal 5) respectively for 1,500 rpm, and 0.94 (Animal 2), 0.85 (Animal 3), 0.94 (Animal 4), and 0.89 (Animal 5) respectively, for 1,700 rpm. The relationship between motor current and pump flow and LV pressure showed an unstable correlation in an in vivo study. These results suggest that motor current amplitude monitoring could be useful as an index for the control of VADs for native heart preservation. PMID:11722346

Kikugawa, D

2001-09-01

142

Simulation of Left Atrial Function Using a Multi-Scale Model of the Cardiovascular System  

PubMed Central

During a full cardiac cycle, the left atrium successively behaves as a reservoir, a conduit and a pump. This complex behavior makes it unrealistic to apply the time-varying elastance theory to characterize the left atrium, first, because this theory has known limitations, and second, because it is still uncertain whether the load independence hypothesis holds. In this study, we aim to bypass this uncertainty by relying on another kind of mathematical model of the cardiac chambers. In the present work, we describe both the left atrium and the left ventricle with a multi-scale model. The multi-scale property of this model comes from the fact that pressure inside a cardiac chamber is derived from a model of the sarcomere behavior. Macroscopic model parameters are identified from reference dog hemodynamic data. The multi-scale model of the cardiovascular system including the left atrium is then simulated to show that the physiological roles of the left atrium are correctly reproduced. This include a biphasic pressure wave and an eight-shaped pressure-volume loop. We also test the validity of our model in non basal conditions by reproducing a preload reduction experiment by inferior vena cava occlusion with the model. We compute the variation of eight indices before and after this experiment and obtain the same variation as experimentally observed for seven out of the eight indices. In summary, the multi-scale mathematical model presented in this work is able to correctly account for the three roles of the left atrium and also exhibits a realistic left atrial pressure-volume loop. Furthermore, the model has been previously presented and validated for the left ventricle. This makes it a proper alternative to the time-varying elastance theory if the focus is set on precisely representing the left atrial and left ventricular behaviors. PMID:23755183

Pironet, Antoine; Dauby, Pierre C.; Paeme, Sabine; Kosta, Sarah; Chase, J. Geoffrey; Desaive, Thomas

2013-01-01

143

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)

2011-01-18

144

Cardiac Health Risk Stratification System (CHRiSS): A Bayesian-Based Decision Support System for Left Ventricular Assist Device (LVAD) Therapy  

PubMed Central

This study investigated the use of Bayesian Networks (BNs) for left ventricular assist device (LVAD) therapy; a treatment for end-stage heart failure that has been steadily growing in popularity over the past decade. Despite this growth, the number of LVAD implants performed annually remains a small fraction of the estimated population of patients who might benefit from this treatment. We believe that this demonstrates a need for an accurate stratification tool that can help identify LVAD candidates at the most appropriate point in the course of their disease. We derived BNs to predict mortality at five endpoints utilizing the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) database: containing over 12,000 total enrolled patients from 153 hospital sites, collected since 2006 to the present day, and consisting of approximately 230 pre-implant clinical variables. Synthetic minority oversampling technique (SMOTE) was employed to address the uneven proportion of patients with negative outcomes and to improve the performance of the models. The resulting accuracy and area under the ROC curve (%) for predicted mortality were 30 day: 94.9 and 92.5; 90 day: 84.2 and 73.9; 6 month: 78.2 and 70.6; 1 year: 73.1 and 70.6; and 2 years: 71.4 and 70.8. To foster the translation of these models to clinical practice, they have been incorporated into a web-based application, the Cardiac Health Risk Stratification System (CHRiSS). As clinical experience with LVAD therapy continues to grow, and additional data is collected, we aim to continually update these BN models to improve their accuracy and maintain their relevance. Ongoing work also aims to extend the BN models to predict the risk of adverse events post-LVAD implant as additional factors for consideration in decision making. PMID:25397576

Loghmanpour, Natasha A.; Druzdzel, Marek J.; Antaki, James F.

2014-01-01

145

Pressure overload-induced mild cardiac hypertrophy reduces left ventricular transmural differences in mitochondrial respiratory chain activity and increases oxidative stress  

PubMed Central

Objective: Increased mechanical stress and contractility characterizes normal left ventricular (LV) subendocardium (Endo) but whether Endo mitochondrial respiratory chain complex activities is reduced as compared to subepicardium (Epi) and whether pressure overload-induced LV hypertrophy (LVH) might modulate transmural gradients through increased reactive oxygen species (ROS) production is unknown. Methods: LVH was induced by 6 weeks abdominal aortic banding and cardiac structure and function were determined with echocardiography and catheterization in sham-operated and LVH rats (n = 10 for each group). Mitochondrial respiration rates, coupling, content and ROS production were measured in LV Endo and Epi, using saponin-permeabilized fibers, Amplex Red fluorescence and citrate synthase activity. Results: In sham, a transmural respiratory gradient was observed with decreases in endo maximal oxidative capacity (?36.7%, P < 0.01) and complex IV activity (?57.4%, P < 0.05). Mitochondrial hydrogen peroxide (H2O2) production was similar in both LV layers. Aortic banding induced mild LVH (+31.7% LV mass), associated with normal LV fractional shortening and end diastolic pressure. LVH reduced maximal oxidative capacity (?23.6 and ?33.3%), increased mitochondrial H2O2 production (+86.9 and +73.1%), free radical leak (+27.2% and +36.3%) and citrate synthase activity (+27.2% and +36.3%) in Endo and Epi, respectively. Transmural mitochondrial respiratory chain complex IV activity was reduced in LVH (?57.4 vs. ?12.2%; P = 0.02). Conclusions: Endo mitochondrial respiratory chain complexes activities are reduced compared to LV Epi. Mild LVH impairs mitochondrial oxidative capacity, increases oxidative stress and reduces transmural complex IV activity. Further studies will be helpful to determine whether reduced LV transmural gradient in mitochondrial respiration might be a new marker of a transition from uncomplicated toward complicated LVH. PMID:22934079

Kindo, Michel; Gerelli, Sebastien; Bouitbir, Jamal; Charles, Anne-Laure; Zoll, Joffrey; Hoang Minh, Tam; Monassier, Laurent; Favret, Fabrice; Piquard, Francois; Geny, Bernard

2012-01-01

146

Resting Heart Rate and Risk of Sudden Cardiac Death in the General Population: Influence of Left Ventricular Systolic Dysfunction and Heart Rate-Modulating Drugs  

PubMed Central

Background Higher levels of resting heart rate (HR) have been associated with sudden cardiac death (SCD) but mechanisms are poorly understood. We hypothesized that severe left ventricular systolic dysfunction (LVSD) and rate-modulating drugs explain the HR-SCD relationship. Objective We evaluated the relationship between HR, severe LVSD, rate-affecting medications and SCD in the community, using a case-control approach. Methods From the ongoing Oregon Sudden Unexpected Death Study, SCD cases (n=378) aged ?35 years and with EKG-documented resting HR, were compared to 378 age- and gender-matched control subjects with coronary artery disease (68±13 years, 69% male). Associations with SCD were assessed using multivariable logistic regression. Results Mean resting HR was significantly higher among SCD cases compared to controls (7.5bpm difference, p<0.0001). Heart rate was a significant determinant of SCD after adjustment for significant co-morbidities and medications [OR for 10 bpm increase = 1.26; 95% CI (1.14 – 1.38); p<0.0001]. After considering LVSD, resting HR was slightly attenuated but remained significantly associated with SCD (p=0.005). In addition to diabetes, and digoxin as well as pulmonary and renal disease, LVSD was also independently associated with SCD (OR 1.79, 95% CI 1.11–2.87, p=0.02). Conclusion Contrary to expectations, the significant relationship between increased resting HR and SCD persisted even after adjustment for LVSD and rate-modulating drugs. These findings suggest a potential role for additional, novel interventions/therapies that modulate autonomic tone. PMID:23680897

Teodorescu, Carmen; Reinier, Kyndaron; Uy-Evanado, Audrey; Gunson, Karen; Jui, Jonathan; Chugh, Sumeet S.

2013-01-01

147

Late Gadolinium Enhancement in Cardiac MRI in Patients with Severe Aortic Stenosis and Preserved Left Ventricular Systolic Function Is Related to Attenuated Improvement of Left Ventricular Geometry and Filling Pressure after Aortic Valve Replacement  

PubMed Central

Background and Objectives We investigated echocardiographic predictors: left ventricular (LV) geometric changes following aortic valve replacement (AVR) according to the late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) in patients with severe aortic stenosis (AS) and preserved LV systolic function. Subjects and Methods We analyzed 41 patients (24 males, 63.1±8.7 years) with preserved LV systolic function who were scheduled to undergo AVR for severe AS. All patients were examined with transthoracic echocardiography (TTE), CMR before and after AVR (in the hospital) and serial TTEs (at 6 and 12 months) were repeated. Results The group with LGE (LGE+) showed greater wall thickness (septum, 14.3±2.6 mm vs. 11.5±2.0 mm, p=0.001, posterior; 14.3±2.5 mm vs. 11.4±1.6 mm, p<0.001), lower tissue Doppler image (TDIS', 4.4±1.4 cm/s vs. 5.5±1.2 cm/s, p=0.021; TDI E', 3.2±0.9 cm/s vs. 4.8±1.4 cm/s, p=0.002), and greater E/e' (21.8±10.3 vs. 15.4±6.3, p=0.066) than those without LGE (LGE-). Multivariate analysis show that TDI e' (odds ratio=0.078, 95% confidence interval=0.007-0.888, p=0.040) was an independent determinant of LGE+. In an analysis of the 6- and 12-month follow-up compared with pre-AVR, LGE- showed decreased LV end-diastolic diameter (48.3±5.0 mm vs. 45.8±3.6 mm, p=0.027; 48.3±5.0 mm vs. 46.5±3.4 mm, p=0.019). Moreover, E/e' (at 12 months) showed further improved LV filling pressure (16.0±6.6 vs. 12.3±4.3, p=0.001) compared with pre-AVR. However, LGE+ showed no significant improvement. Conclusion The absence of LGE is associated with favorable improvements in LV geometry and filling pressure. TDI E' is an independent determinant of LGE in patients with severe AS and preserved LV systolic function. PMID:25278984

Park, Junbeom; Choi, Jung-Ho; Yang, Pil-Sung; Lee, Sang-Eun; Heo, Ran; Shin, Sanghoon; Cho, In-Jeong; Kim, Young-Jin; Shim, Chi Young; Hong, Geu-Ru; Chung, Namsik

2014-01-01

148

Adult teleost heart expresses two distinct troponin C paralogs: cardiac TnC and a novel and teleost-specific ssTnC in a chamber- and temperature-dependent manner.  

PubMed

The teleost-specific whole genome duplication created multiple copies of genes allowing for subfunctionalization of isoforms. In this study, we show that the teleost cardiac Ca2+-binding troponin C (TnC) is the product of two distinct genes: cardiac TnC (cTnC, TnnC1a) and a fish-specific slow skeletal TnC (ssTnC, TnnC1b). The ssTnC gene is novel to teleosts as mammals have a single gene commonly referred as cTnC but which is also expressed in slow skeletal muscle. In teleosts, the data strongly indicate that these are two TnC genes are different paralogs. Because we determined that ssTnC exists across many teleosts but not in basal ray-finned fish (e.g., bichir), we propose that these paralogs are the result of an ancestral tandem gene duplication persisting only in teleosts. Quantification of mRNA levels was used to demonstrate distinct expression localization patterns of the paralogs within the chambers of the heart. In the adult zebrafish acclimated at 28°C, ssTnC mRNA levels are twofold greater than cTnC mRNA levels in the atrium, whereas cTnC mRNA was almost exclusively expressed in the ventricle. Meanwhile, rainbow trout acclimated at 5°C showed cTnC mRNA levels in both chambers significantly greater than ssTnC. Distinct responses to temperature acclimation were also quantified in both adult zebrafish and rainbow trout, with mRNA in both chambers shifting to express higher levels of cTnC in 18°C acclimated zebrafish and 5°C acclimated trout. Possible subfunctionalization of TnC isoforms may provide insight into how teleosts achieve physiological versatility in chamber-specific contractile properties. PMID:23881286

Genge, Christine E; Davidson, William S; Tibbits, Glen F

2013-09-16

149

Characterization of Respiratory and Cardiac Motion from Electro-Anatomical Mapping Data for Improved Fusion of MRI to Left Ventricular Electrograms  

PubMed Central

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

150

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. PMID:22270108

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

2012-01-01

151

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

NASA Astrophysics Data System (ADS)

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 ten 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.

2012-10-01

152

Institutional report - Cardiac general Surgery of left ventricular aneurysm: a propensity score-matched study of outcomes following different repair techniques  

Microsoft Academic Search

To evaluate early and late outcomes of modified left ventricular reconstruction (VR) and linear repair (LR) of post-infarct left ventricular aneurysm (LVA ). A total of 514 patients were consecutively operated on for LVA with modified VR technique in 145 and LR in 352 patients. Using the propensity score-matching method, we selected 202 patients (101 LRs vs. 101 VRs) with

Zhe Zheng; Hongguang Fan; Wei Feng; Shiju Zhang; Xin Yuan; Liqing Wang; Yunhu Song; Shengshou Hu

153

Chapter 2 Background and Method Overview The cardiac left ventricle is one of the most crucial and thoroughly studied structures in the  

E-print Network

tissue, but this occurs without the normal increase in wall thickness. Thus, as a pump the heart may be given by chest compressions during cardiopulmonary resuscitation or by external or implanted pumps cardiac contraction generally causes concentric sections of the myocardial wall to move inward, thereby

Stetten, George

154

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

155

Congenital coronary artery fistula in an intercoronary communication between the left main and the diagonal branch of the left anterior descending coronary artery: an interesting case report.  

PubMed

Intercoronary communication is a very rare coronary artery anomaly. It is defined as an open-ended circulation with bidirectional blood flow between two coronary arteries. Coronary artery fistulas are abnormal communications between a coronary artery and a cardiac chamber or major vessel. A 62-year-old man was admitted to our hospital with sudden development of general weakness, dizziness and a sensation of compression in his chest. At presentation his blood pressure was 80/40 mmHg and heart rate was 65 beats/min. The ECG revealed sinus rhythm and 1-2 mm ST elevation in the anterior leads. The patient was taken to the catheterization laboratory for percutaneous coronary intervention. The left main and left circumflex coronary arteries were normal. Coronary angiography showed a communication between the left main and the diagonal branch of the left anterior descending and a fistula between the intercoronary connection and the left atrium. The other coronary arteries were normal. Laboratory test results, including cardiac troponin I and creatine kinase-MB levels, were normal. The angina symptoms disappeared and the ST elevation resolved within four hours. We report an interesting case of congenital coronary artery fistula in an intercoronary communication between the left main and the diagonal branch of the left anterior descending coronary artery presenting as an acute coronary syndrome. To the best of our knowledge, this is the first case in the literature involving a coronary artery fistula in an intercoronary communication. PMID:24411822

Turker, Yasin; Tibilli, Hakan

2014-01-01

156

A Rare Case of Left Ventricular Intramural Hemangioma Diagnosed Using 1.5-T Cardiac MRI with Histopathological Correlation and Successfully Treated by Surgery  

SciTech Connect

Hemangiomas are vascular tumors composed of blood vessels, frequently localized in the skin and subcutaneous muscles; their localization in the heart is exceptional. The most common localizations are the lateral walls of the left ventricle, the anterior wall, and the septum. Mostly, these tumors grow intracavitarily, rarely intramurally. We describe a singular case of left ventricular intramural hemangioma, detected and diagnosed using newer magnetic resonance imaging (MRI) modalities, confirmed by histopathological results, and treated successfully by surgery.

Marrone, Gianluca, E-mail: gmarrone@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Diagnostic and Interventional Radiology (Italy); Sciacca, Sergio, E-mail: ssciacca@ismett.edu; D'Ancona, Giuseppe, E-mail: gdancona@ismett.edu; Pilato, Michele, E-mail: mpilato@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Division of Cardiac Surgery (Italy); Luca, Angelo, E-mail: aluca@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Diagnostic and Interventional Radiology (Italy); Gridelli, Bruno, E-mail: bgridelli@ismett.ed [Mediterranean Institute of Transplantation and High Specialization Therapy (ISMETT), Division of Surgery (Italy)

2010-02-15

157

Cardiac-Specific Inhibition of Kinase Activity in Calcium/Calmodulin-Dependent Protein Kinase Kinase-? Leads to Accelerated Left Ventricular Remodeling and Heart Failure after Transverse Aortic Constriction in Mice  

PubMed Central

Background The mechanism of cardiac energy production against sustained pressure overload remains to be elucidated. Methods and Results We generated cardiac-specific kinase-dead (kd) calcium/calmodulin-dependent protein kinase kinase-? (CaMKK?) transgenic (?-MHC CaMKK?kd TG) mice using ?-myosin heavy chain (?-MHC) promoter. Although CaMKK? activity was significantly reduced, these mice had normal cardiac function and morphology at baseline. Here, we show that transverse aortic binding (TAC) in ?-MHC CaMKK?kd TG mice led to accelerated death and left ventricular (LV) dilatation and dysfunction, which was accompanied by significant clinical signs of heart failure. CaMKK? downstream signaling molecules, including adenosine monophosphate-activated protein kinase (AMPK), were also suppressed in ?-MHC CaMKK?kd TG mice compared with wild-type (WT) mice. The expression levels of peroxisome proliferator-activated receptor-? coactivator (PGC)-1?, which is a downstream target of both of CaMKK? and calcium/calmodulin kinases, were also significantly reduced in ?-MHC CaMKK?kd TG mice compared with WT mice after TAC. In accordance with these findings, mitochondrial morphogenesis was damaged and creatine phosphate/?-ATP ratios assessed by magnetic resonance spectroscopy were suppressed in ?-MHC CaMKK?kd TG mice compared with WT mice after TAC. Conclusions These data indicate that CaMKK? exerts protective effects on cardiac adaptive energy pooling against pressure-overload possibly through phosphorylation of AMPK and by upregulation of PGC-1?. Thus, CaMKK? may be a therapeutic target for the treatment of heart failure. PMID:25255457

Watanabe, Shin; Horie, Takahiro; Nagao, Kazuya; Kuwabara, Yasuhide; Baba, Osamu; Nishi, Hitoo; Sowa, Naoya; Narazaki, Michiko; Matsuda, Tetsuya; Takemura, Genzou; Wada, Hiromichi; Hasegawa, Koji; Kimura, Takeshi; Ono, Koh

2014-01-01

158

Preoperative levosimendan decreases mortality and the development of low cardiac output in high-risk patients with severe left ventricular dysfunction undergoing coronary artery bypass grafting with cardiopulmonary bypass  

PubMed Central

BACKGROUND: The calcium sensitizer levosimendan has been used in cardiac surgery for the treatment of postoperative low cardiac output syndrome (LCOS) and difficult weaning from cardiopulmonary bypass (CPB). OBJECTIVES: To evaluate the effects of preoperative treatment with levosimendan on 30-day mortality, the risk of developing LCOS and the requirement for inotropes, vasopressors and intra-aortic balloon pumps in patients with severe left ventricular dysfunction. METHODS: Patient with severe left ventricular dysfunction and an ejection fraction <25% undergoing coronary artery bypass grafting with CPB were admitted 24 h before surgery and were randomly assigned to receive levosimendan (loading dose 10 ?g/kg followed by a 23 h continuous infusion of 0.1?g/kg/min) or a placebo. RESULTS: From December 1, 2002 to June 1, 2008, a total of 252 patients were enrolled (127 in the levosimendan group and 125 in the control group). Individuals treated with levosimendan exhibited a lower incidence of complicated weaning from CPB (2.4% versus 9.6%; P<0.05), decreased mortality (3.9% versus 12.8%; P<0.05) and a lower incidence of LCOS (7.1% versus 20.8%; P<0.05) compared with the control group. The levosimendan group also had a lower requirement for inotropes (7.9% versus 58.4%; P<0.05), vasopressors (14.2% versus 45.6%; P<0.05) and intra-aortic balloon pumps (6.3% versus 30.4%; P<0.05). CONCLUSION: Patients with severe left ventricle dysfunction (ejection fraction <25%) undergoing coronary artery bypass grafting with CPB who were pretreated with levosimendan exhibited lower mortality, a decreased risk for developing LCOS and a reduced requirement for inotropes, vasopressors and intra-aortic balloon pumps. Studies with a larger number of patients are required to confirm whether these findings represent a new strategy to reduce the operative risk in this high-risk patient population. PMID:23620700

Levin, Ricardo; Degrange, Marcela; Del Mazo, Carlos; Tanus, Eduardo; Porcile, Rafael

2012-01-01

159

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. PMID:21967903

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

2013-01-01

160

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. PMID:24748728

Murugan, Ponniah Senthil; Selvam, Govindan Sadasivam

2014-01-01

161

Time Components of the Left Ventricle.  

ERIC Educational Resources Information Center

The purpose of this study was to examine the relationship of the time components of the left ventricle. Since one of the ways to investigate cardiac function is to analyze the time intervals between particular events of the cardiac cycle, various time intervals of systole and diastole of the left ventricle were measured from simultaneous…

Franks, B. Don

162

Four patients with Sillence type I osteogenesis imperfecta and mild bone fragility, complicated by left ventricular cardiac valvular disease and cardiac tissue fragility caused by type I collagen mutations.  

PubMed

Osteogenesis imperfecta (OI) type I is a hereditary disorder of connective tissue (HDCT) characterized by blue or gray sclerae, variable short stature, dentinogenesis imperfecta, hearing loss, and recurrent fractures from infancy. We present four examples of OI type I complicated by valvular heart disease and associated with tissue fragility. The diagnosis of a type I collagen disorder was confirmed by abnormal COL1A1 or COL1A2 gene sequencing. One patient was investigated with electrophoresis of collagens from cultured skin fibroblasts, showing structurally abnormal collagen type I, skin biopsy showed unusual histology and abnormal collagen fibril ultra-structure at electron microscopy. The combined clinical, surgical, histological, ultra-structural, and molecular genetic data suggest the type I collagen defect as contributory to cardiac valvular disease. The degree of tissue fragility experienced at cardiac surgery in these individuals, also reported in a small number of similar case reports, suggests that patients with OI type I need careful pre-operative assessment and consideration of the risks and benefits of cardiac surgery. PMID:24311407

Vandersteen, Anthony M; Lund, Allan M; Ferguson, David J P; Sawle, Philip; Pollitt, Rebecca C; Holder, Susan E; Wakeling, Emma; Moat, Neil; Pope, F Michael

2014-02-01

163

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

164

Dietary saturated fat and docosahexaenoic acid differentially effect cardiac mitochondrial phospholipid fatty acyl composition and Ca(2+) uptake, without altering permeability transition or left ventricular function.  

PubMed

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 Ca(2+)-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 Ca(2+) 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. PMID:24303101

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

2013-06-01

165

Effects of Verapamil on Top of Trandolapril on Exercise Tolerance and Cardiac Performance in Patients with Hypertension and Reduced Left Ventricular Function  

Microsoft Academic Search

Calcium antagonists and angiotensin-converting enzyme (ACE) inhibitors act synergistically in reducing blood pressure through additive hemodynamic and vasculoprotective effects. Objectives: The aim of this study was to investigate the hemodynamic and neurohumoral effects of combined verapamil SR plus trandolapril treatment (verapamil SR\\/trandolapril) versus trandolapril monotherapy at rest and during exercise in patients with essential hypertension (WHO I–II) and mild left

V. Mitrovic; D. Djuric; W. D. Patyna; B. Urgatz; M. Parzeller; T. Notter

2001-01-01

166

Cardiac sympathetic denervation does not change the load dependence of the left ventricular end-systolic pressure\\/volume relationship in dogs  

Microsoft Academic Search

It has been shown that in the intact canine heart the left-ventricular end-systolic pressure\\/volume relation (ESPVR) depends on loading conditions: an increase in arterial vascular resistance causes a leftwards shift and a steeper slope of the ESPVR, suggesting an increased inotropic state. Our purpose was to investigate the possible contribution of the sympathetic nervous system to this load sensitivity of

Inger B. Schipper; Paul Steendijk; Robert J. M. Klautz; Enno T. van der Velde; Jan Baan

1993-01-01

167

Beneficial effects of elevating cardiac preload on left-ventricular diastolic function and volume during heat stress: implications toward tolerance during a hemorrhagic insult.  

PubMed

Volume loading normalizes tolerance to a simulated hemorrhagic challenge in heat-stressed individuals, relative to when these individuals are thermoneutral. The mechanism(s) by which this occurs is unknown. This project tested two unique hypotheses; that is, the elevation of central blood volume via volume loading while heat stressed would 1) increase indices of left ventricular diastolic function, and 2) preserve left ventricular end-diastolic volume (LVEDV) during a subsequent simulated hemorrhagic challenge induced by lower-body negative pressure (LBNP). Indices of left ventricular diastolic function were evaluated in nine subjects during the following conditions: thermoneutral, heat stress, and heat stress after acute volume loading sufficient to return ventricular filling pressures toward thermoneutral levels. LVEDV was also measured in these subjects during the aforementioned conditions prior to and during a simulated hemorrhagic challenge. Heat stress did not change indices of diastolic function. Subsequent volume infusion elevated indices of diastolic function, specifically early diastolic mitral annular tissue velocity (E') and early diastolic propagation velocity (E) relative to both thermoneutral and heat stress conditions (P < 0.05 for both). Heat stress reduced LVEDV (P < 0.05), while volume infusion returned LVEDV to thermoneutral levels. The reduction in LVEDV to LBNP was similar between thermoneutral and heat stress conditions, whereas the reduction after volume infusion was attenuated relative to both conditions (P < 0.05). Absolute LVEDV during LBNP after volume loading was appreciably greater relative to the same level of LBNP during heat stress alone. Thus, rapid volume infusion during heat stress increased indices of left ventricular diastolic function and attenuated the reduction in LVEDV during LBNP, both of which may serve as mechanisms by which volume loading improves tolerance to a combined hyperthermic and hemorrhagic challenge. PMID:25163916

Brothers, R M; Pecini, Redi; Dalsgaard, M; Bundgaard-Nielsen, Morten; Wilson, Thad E; Secher, Niels H; Crandall, Craig G

2014-10-15

168

Age and gender-specific differences in left and right ventricular cardiac function and mass determined by cine magnetic resonance imaging  

Microsoft Academic Search

.   We examined possible age- and gender-specific differences in the function and mass of left (LV) and right (RV) ventricles\\u000a in 36 healthy volunteers using cine gradient-recalled echo magnetic resonance imaging. Subjects were divided into four groups\\u000a (nine men and nine women in each): men aged under 45 years (32 ± 7), women aged under 45 (27 ± 6), men

J. Sandstede; C. Lipke; M. Beer; S. Hofmann; T. Pabst; W. Kenn; S. Neubauer; D. Hahn

2000-01-01

169

Biomechanics of Early Cardiac Development  

PubMed Central

Biomechanics affect early cardiac development, from looping to the development of chambers and valves. Hemodynamic forces are essential for proper cardiac development, and their disruption leads to congenital heart defects. A wealth of information already exists on early cardiac adaptations to hemodynamic loading, and new technologies, including high resolution imaging modalities and computational modeling, are enabling a more thorough understanding of relationships between hemodynamics and cardiac development. Imaging and modeling approaches, used in combination with biological data on cell behavior and adaptation, are paving the road for new discoveries on links between biomechanics and biology and their effect on cardiac development and fetal programming. PMID:22760547

Goenezen, Sevan; Rennie, Monique Y.

2012-01-01

170

Wire chamber  

DOEpatents

A wire chamber or proportional counter device, such as Geiger-Mueller tube or drift chamber, improved with a gas mixture providing a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor.

Atac, Muzaffer (Wheaton, IL)

1989-01-01

171

Surgical treatment of systemic embolization by cardiac metastasis of lung cancer.  

PubMed

Pulmonary vein infiltration from a malignant lung neoplasm is a serious condition that may result in a constant source of systemic emboli. Although surgery is often indicated to prevent recurrent embolism, aggressive approaches have shown a high rate of perioperative morbidity. We herein report the case of a patient diagnosed with lung cancer infiltrating the cardiac chambers through the left superior pulmonary vein, who was treated by left pulmonary vein patch closure as a preventive and less invasive measure to reduce the thromboembolic risk. PMID:24887850

Santise, Gianluca; Raffa, Giuseppe Maria; Pilato, Michele

2014-11-01

172

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

173

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

174

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

175

RELATIONSHIP OF LEFT VENTRICULAR SIZE TO LEFT ATRIAL AND LEFT ATRIAL APPENDAGE SIZE IN SINUS RHYTHM PATIENTS WITH DILATED CARDIOMYOPATHY  

PubMed Central

Introduction: Thromboembolic events are a frequent cause of mortality in patients with congestive heart failure. The aim of or study was to evaluate the relationship of left ventricular end diastolic diameter (LVEDD) to left atrial (LA) size and left atrial appendage (LAA) size in patients with dilated cardiomyopathy in sinus rhythm, as well as to determine the prevalence of thrombi in LV and LA /LAA. Methods: This was a prospective cross-sectional study, conducted from December 2009 until December 2011. The study included 95 patients with dilated cardiomyopathy in sinus rhythm. Patients with swallowing problems, acute myocardial infarction, atrial fibrillation/flatter, severe systolic dysfunction, and/or patients who were taking oral anticoagulation therapy were excluded. Results: Mean patient age was 58.6 ± 12.2 years and 68.4% were men. Mean LVEDD of our population was 66.5 ± 6.5 mm, while mean LA atrium, LA volume and LAA maximal area were 46 ± 5.1 mm, 87.2 ± 38.7 cm3 and 4.7 ± 1.2 cm2, respectively. LA diameter (p<0.001) and LAA maximal area (p=0.01) showed to be independent predictors of LV size. LV thrombus was detected in 13 (13.7%) patients, while LAA thrombus in 46 (48.4%) patients of our study population. Conclusions: In conclusion, dilated LV size is associated with enlarged LA and LAA size. On the other hand, dilation of LV, LA and LAA is related to high prevalence of left chamber cardiac thrombi. PMID:23322961

Bakalli, Aurora; Georgievska-Ismail, Ljubica; Musliu, Nebi; Kocinaj, Dardan; Gashi, Zaim; Zeqiri, Nexhmi

2012-01-01

176

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

177

Nervous activity of afferent cardiac sympathetic fibres with atrial and ventricular endings  

PubMed Central

1. We recorded the electrical activity of single afferent cardiac fibres isolated from the third and fourth left thoracic sympathetic rami communicantes of anaesthetized cats. Their conduction velocities ranged from 12 to 32 m/sec. 2. The endings of each fibre were localized to one cardiac chamber by mechanical probing of the opened heart performed at the end of the experiment. 3. The impulse activity was spontaneous and, in fibres with atrial or ventricular endings, it was in phase with a particular atrial or ventricular event. 4. This nervous activity increased during increases in pressure occurring in the chamber where the endings were located. Conversely, decreases in pressure were accompanied by decreased nervous discharge. 5. In some experiments the left coronary artery was perfused at different flows and pressures. Brief decreases or increases in coronary flow and pressure decreased or increased, respectively, the discharge of fibres with atrial or ventricular endings. Fibres were excited by intracoronary injections of veratridine. 6. Cessation of coronary pump flow increased the discharge of fibres with atrial or ventricular endings only when myocardial ischaemia was accompanied by signs of heart failure. 7. These afferent cardiac sympathetic fibres which provide the spinal cord with continuous specific information on cardiac events are likely to contribute to the neural control of circulation. PMID:4724832

Malliani, A.; Recordati, G.; Schwartz, P. J.

1973-01-01

178

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

179

Hybrid procedures in pediatric cardiac surgery  

Microsoft Academic Search

Hybrid pediatric cardiac surgery is an emerging field that combines skills and techniques used by pediatric cardiac surgeons and interventional pediatric cardiologists. This article describes the emerging indications and techniques in hybrid pediatric cardiac surgery and discusses potential future applications. It focuses on peratrial and perventricular septal defect closure, intraoperative stenting, hybrid stage I palliation for hypoplastic left heart syndrome,

Emile A. M. Bacha; Ziyad M. Hijazi

2005-01-01

180

Contrast echocardiography for assessment of left ventricular thrombi.  

PubMed

The diagnosis of intracardiac thrombi remains clinically relevant, with associated risks of systemic embolization and implications for antithrombotic management. Intravenously injected ultrasound contrast agents, composed of microbubbles smaller than red blood cells, have become established essential adjunctive tools for performance of state-of-the-art echocardiography, providing important information on cardiac structure and function. Despite advances in other imaging modalities, echocardiography remains the initial tool for diagnosis and risk stratification in patients predisposed to developing cardiac thrombi. Ultrasound contrast agents are approved for left ventricular (LV) opacification and endocardial border definition. Additionally, the use of contrast echocardiography facilitates LV thrombus detection by providing contrast opacification within the cardiac chambers to clearly show the "filling defect" of an intracardiac thrombus. Furthermore, contrast perfusion echocardiography can provide an assessment of the tissue characteristics of LV masses suspicious for intracardiac thrombi and, by differentiating an avascular thrombus from a tumor, results in improved diagnostic performance of echocardiography. This article presents a clinical vignette highlighting the sound judgment of using contrast echocardiography to aid in the diagnosis of LV thrombi and will review recent advances in imaging modalities for intracardiac thrombus detection. PMID:25063398

Abdelmoneim, Sahar S; Pellikka, Patricia A; Mulvagh, Sharon L

2014-08-01

181

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

PubMed Central

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.

2013-01-01

182

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. PMID:24782967

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

2014-01-01

183

Anomalous Left Coronary Artery From the Pulmonary Artery (ALCAPA)  

Microsoft Academic Search

Anomalous left coronary artery from the pulmonary artery, or ALCAPA, is a rare, congenital cardiac anomaly. The condition causes ischemia and, if left untreated, can lead to death. It is important for cardiac sonographers to recognize the signs, symptoms, and sonographic characteristics of ALCAPA. A case of ALCAPA diagnosed by echocardiography is presented.

Kristen Hallmark

2005-01-01

184

Cardiac lipofibromatosis.  

PubMed

We present a case of cardiac lipofibromatosis associated with atrial fibrillation and complete heart block requiring permanent pacemaker implantation. Multimodality cardiac imaging including transthoracic echocardiography and cardiac magnetic resonance were useful for tissue characterization of this rare cardiac diagnosis. PMID:23146562

Shen, Seeger; Rizkallah, Jacques; Kirkpatrick, Iain D C; Khadem, Ali; Jassal, Davinder S

2013-04-01

185

Multiple Papillary Fibroelastomas and Thrombus in the Left Heart  

PubMed Central

Cardiac papillary fibroelastomas (CPF) are benign cardiac tumors and usually discovered incidentally during echocardiography. This report describes the case of a 68-year-old man, referred to cardiology for multiple masses of the left ventricle and left atrium. The transthoracic echocardiography revealed multiple oscillating masses in the left ventricle and aortic valve, non-mobile mass in the left atrium with severe mitral stenosis and moderate aortic regurgitation. The patient underwent surgical resection of the masses with valve replacements. Histopathologic examination confirmed the diagnosis of CPF in the left ventricle and aortic valve, thrombus in the left atrium. PMID:24753809

Seo, Guang-Won; Park, Bo-Min; Kim, Tae-Jin; Kim, Jae-Kyun; Song, Pil-Sang; Kim, Dong-Kie; Kim, Ki-Hun; Kim, Yeon Mee; Kim, Doo-Il

2014-01-01

186

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

187

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

188

Chamber propagation  

SciTech Connect

Propagation of a heavy ion beam to the target appears possible under conditions thought to be realizable by several reactor designs. Beam quality at the lens is believed to provide adequate intensity at the target -- but the beam must pass through chamber debris and its self fields along the way. This paper reviews present consensus on propagation modes and presents recent results on the effects of photoionization of the beam ions by thermal x-rays from the heated target. Ballistic propagation through very low densities is a conservative mode. The more-speculative self-pinched mode, at 1 to 10 Torr, offers reactor advantages and is being re-examined by others. 13 refs.

Langdon, B.

1991-01-16

189

Chamber transport  

SciTech Connect

Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

OLSON,CRAIG L.

2000-05-17

190

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. PMID:24814127

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

2014-01-01

191

Malignant phyllodes tumor of the left atrium.  

PubMed

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. PMID:24814127

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

2014-01-01

192

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

193

Cardiac Transplantation in Friedreich Ataxia  

PubMed Central

In this paper, we describe a 14-year-old boy with a confirmed diagnosis of Friedreich ataxia who underwent cardiac transplantation for left ventricular failure secondary to dilated cardiomyopathy with restrictive physiology. His neurological status prior to transplantation reflected early signs of neurologic disease, with evidence of dysarthria, weakness, mild gait impairment, and limb ataxia. We review the ethical issues considered during the process leading to the decision to offer cardiac transplantation. PMID:22752490

Yoon, Grace; Soman, Teesta; Wilson, Judith; George, Kristen; Mital, Seema; Dipchand, Anne I.; McCabe, Jane; Logan, William; Kantor, Paul

2013-01-01

194

Effects of dynamic cardiomyoplasty on left ventricular performance and myocardial mechanics in dilated cardiomyopathy.  

PubMed

We tested the hypothesis that dynamic cardiomyoplasty produces beneficial changes in the functional mechanics of the dilated, failing left ventricle. Chronic dilated cardiomyopathy was induced in seven mongrel dogs by rapid ventricular pacing (260 beats/min) for 3 to 4 weeks. After completion of the induction period, dynamic cardiomyoplasty was performed with the left latissimus dorsi muscle, paced synchronously with the R waves of the electrocardiogram (Medtronic SP1005). Instruments included an aortic flow probe, a left ventricular Millar pressure catheter, and piezoelectric sonomicrometric crystals on the left ventricle for measurements of wall thickness and minor and major axis dimensions. Data were obtained with the stimulator off and on. Statistical comparisons were made with Student's t test for paired data. Dynamic cardiomyoplasty increased the cardiac output of the failing heart (966 +/- 124 versus 1166 +/- 112 ml/min; p less than 0.01). Systolic shortening of both minor and major axis dimensions increased (3.1 +/- 0.3 versus 4.7 +/- 0.3 mm, p less than 0.01, and 4.6 +/- 0.3 versus 7.3 +/- 0.9 mm, p less than 0.05, respectively). Left ventricular end-diastolic pressure decreased by 16% (18 +/- 1 versus 15 +/- 1 mm Hg, p less than 0.01). Although skeletal muscle contraction increased the pressure development in the left ventricular chamber, mean systolic wall stress was diminished by concomitant changes in left ventricular dimensions (116,144 +/- 11,530 versus 101,268 +/- 7464 dynes/cm2, p less than 0.05). At end-systole, wall thickness increased (11.8 +/- 1.1 versus 12.7 +/- 1.1 mm, p less than 0.01), minor axis dimension decreased (51.3 +/- 1.4 versus 49.2 +/- 1.8 mm, p less than 0.01), and major axis dimension also decreased (85.6 +/- 3.3 versus 79.0 +/- 2.3 mm, p less than 0.05). Our detailed evaluation of left ventricular chamber mechanics suggests that dynamic cardiomyoplasty may have a role in ameliorating the functional and mechanical derangements associated with progression of dilated cardiomyopathy both by augmenting cardiac performance and by diminishing determinants of myocardial oxygen consumption. (All values are expressed as mean +/- standard error of the mean.) PMID:2072710

Lee, K F; Dignan, R J; Parmar, J M; Dyke, C M; Benton, G; Yeh, T; Abd-Elfattah, A S; Wechsler, A S

1991-07-01

195

Videoscope-assisted cardiac surgery  

PubMed Central

Videoscope-assisted cardiac surgery (VACS) offers a minimally invasive platform for most cardiac operations such as coronary and valve procedures. It includes robotic and thoracoscopic approaches and each has strengths and weaknesses. The success depends on appropriate hardware setup, staff training, and troubleshooting efficiency. In our institution, we often use VACS for robotic left-internal-mammary-artery takedown, mitral valve repair, and various intra-cardiac operations such as tricuspid valve repair, combined Maze procedure, atrial septal defect repair, ventricular septal defect repair, etc. Hands-on reminders and updated references are provided for reader’s further understanding of the topic. PMID:24455172

Chen, Robert Jeen-Chen

2014-01-01

196

Functional Modulation of Cardiac Form through Regionally Confined Cell Shape  

Microsoft Academic Search

Developing organs acquire a specific three-dimensional form that ensures their normal function. Cardiac function, for example, depends upon properly shaped chambers that emerge from a primitive heart tube. The cellular mechanisms that control chamber shape are not yet understood. Here, we demonstrate that chamber morphology develops via changes in cell morphology, and we determine key regulatory influences on this process.

Heidi J. Auman; Hope Coleman; Heather E. Riley; Felix Olale; Huai-Jen Tsai; Deborah Yelon

197

Cardiac myxosarcoma with thoracic spinal metastasis.  

PubMed

Echocardiography revealed a left atrial tumor in a 59-year-old man with back pain that concurrently worsened with left foot drop and loss of the left ankle reflex soon after admission to our hospital. Magnetic resonance imaging of the spine revealed an epidural tumor extending from Th5 with spinal cord compression. The patient was immediately treated by emergency Th4-5 laminectomy and epidural decompression. One month later, a cardiac tumor excised via the left atrial approach was histopathologically diagnosed as myxosarcoma, and the Th5 tumor was consistent with this finding. This is the first report to describe spinal metastasis of cardiac myxosarcoma. PMID:23677508

Kimura, Mitsuhiro; Kikuchi, Chizuo; Takahashi, Yoshiki; Kanazawa, Hiroshi; Nakazawa, Satoshi

2014-07-01

198

Cardiac abnormalities in young women with anorexia nervosa.  

PubMed Central

OBJECTIVE--To identify the characteristics of cardiac involvement in the self-induced starvation phase of anorexia nervosa. METHODS--Doppler echocardiographic indices of left ventricular geometry, function, and filling were examined in 21 white women (mean (SD) 22 (5) years) with anorexia nervosa according to the DSMIII (Diagnostic and Statistical Manual of Mental Disorders) criteria, 19 women (23 (2) years) of normal weight, and 22 constitutionally thin women (21 (4) years) with body mass index < 20. RESULTS--13 patients (62%) had abnormalities of mitral valve motion compared with one normal weight woman and two thin women (p < 0.001) v both control groups). Left ventricular chamber dimension and mass were significantly less in women with anorexia nervosa than in either the women of normal weight or the thin women, even after standardisation for body size or after controlling for blood pressure. There were no substantial changes in left ventricular shape. Midwall shortening as a percentage of the values predicted from end systolic stress was significantly lower in the starving patients than in women of normal weight: when endocardial shortening was used as the index this difference was overestimated. The cardiac index was also significantly reduced in anorexia nervosa because of a low stroke index and heart rate. The total peripheral resistance was significantly higher in starving patients than in both control groups. The left atrial dimension was significantly smaller in anorexia than in the women of normal weight and the thin women, independently of body size. The transmitral flow velocity E/A ratio was significantly higher in anorexia than in both the control groups because of the reduction of peak velocity A. When data from all three groups were pooled the flow velocity E/A ratio was inversely related to left atrial dimension (r = -0.43, p < 0.0001) and cardiac output (r = -0.64, p < 0.0001) independently of body size. CONCLUSIONS--Anorexia nervosa caused demonstrable abnormalities of mitral valve motion and reduced left ventricular mass and filling associated with systolic dysfunction. PMID:8142200

de Simone, G.; Scalfi, L.; Galderisi, M.; Celentano, A.; Di Biase, G.; Tammaro, P.; Garofalo, M.; Mureddu, G. F.; de Divitiis, O.; Contaldo, F.

1994-01-01

199

Optimal vortex formation as an index of cardiac health  

Microsoft Academic Search

Heart disease remains a leading cause of death worldwide. Previous research has indicated that the dynamics of the cardiac left ventricle (LV) during diastolic filling may play a critical role in dictating overall cardiac health. Hence, numerous studies have aimed to predict and evaluate global cardiac health based on quantitative parameters describing LV function. However, the inherent complexity of LV

Morteza Gharib; Edmond Rambod; Arash Kheradvar; David J. Sahn; John O. Dabiri

2006-01-01

200

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

201

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. PMID:22778489

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

202

Alterations in left ventricular volumes induced by Valsalva manoeuvre  

NASA Technical Reports Server (NTRS)

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

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

1974-01-01

203

Malignant arrhythmia with benign tumour: fibrolipoma of the left ventricle.  

PubMed

We report a case of young male referred for evaluation of recent onset recurrent syncope. Inhospital electrocardiogram revealed an episode of ventricular flutter which reverted spontaneously to sinus rhythm. Transthoracic echocardiogram showed hyperechoic mass in the left ventricle. For further tissue characterization a cardiac magnetic resonance imaging was done which revealed a left ventricular mass with predominant fat content. The tumor was surgically resected. Histopathological examination confirmed the diagnosis of cardiac fibrolipoma. The patient recovered and is currently asymptomatic. PMID:25309694

Sajeev, Chakanalil Govindan; Kalathingathodika, Sajeer; Nair, Anishkumar; Muneer, Kader; Rajesh, Gopalan Nair; Deshabandhu, Vinayakumar; Subramaniam, Gomathy; Pillai, Rajesh Sadanandan; Kuriakose, Kudakkachira Mathew; Krishnan, Mangalath Narayanan

2014-09-01

204

Malignant Arrhythmia with Benign Tumour: Fibrolipoma of the Left Ventricle  

PubMed Central

We report a case of young male referred for evaluation of recent onset recurrent syncope. Inhospital electrocardiogram revealed an episode of ventricular flutter which reverted spontaneously to sinus rhythm. Transthoracic echocardiogram showed hyperechoic mass in the left ventricle. For further tissue characterization a cardiac magnetic resonance imaging was done which revealed a left ventricular mass with predominant fat content. The tumor was surgically resected. Histopathological examination confirmed the diagnosis of cardiac fibrolipoma. The patient recovered and is currently asymptomatic.

Sajeev, Chakanalil Govindan; Nair, Anishkumar; Muneer, Kader; Rajesh, Gopalan Nair; Deshabandhu, Vinayakumar; Subramaniam, Gomathy; Pillai, Rajesh Sadanandan; Kuriakose, Kudakkachira Mathew; Krishnan, Mangalath Narayanan

2014-01-01

205

Cardiac metastases  

Microsoft Academic Search

Tumours metastatic to the heart (cardiac metastases) are among the least known and highly debated issues in oncology, and few systematic studies are devoted to this topic. Although primary cardiac tumours are extremely uncommon (various postmortem studies report rates between 0.001% and 0.28%), secondary tumours are not, and at least in theory, the heart can be metastasised by any malignant

R Bussani; F De-Giorgio; A Abbate; F Silvestri

2007-01-01

206

Cardiac asthma.  

PubMed

Cardiac dyspnea, especially if present only with exercise, is often confused with asthma and exercise-induced bronchospasm. Cardiac dyspnea or asthma is the consequence of pulmonary edema due to pulmonary venous hypertension and not due to asthmatic bronchoconstriction. In overt, acute congestive heart failure, the diagnosis may be readily made by history and physical examination and pertinent laboratory and imaging data. PMID:23337063

Buckner, Kern

2013-02-01

207

An integrated platform for image-guided cardiac resynchronization therapy  

NASA Astrophysics Data System (ADS)

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

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

2012-05-01

208

The cardiac malpositions.  

PubMed

Dextrocardia was known in the 17th century and was 1 of the first congenital malformations of the heart to be recognized. Fifty years elapsed before Matthew Baillie published his account of complete transposition in a human of the thoracic and abdominal viscera to the opposite side from what is natural. In 1858, Thomas Peacock stated that "the heart may be congenitally misplaced in various ways, occupying either an unusual position within the thorax, or being situated external to that cavity." In 1915, Maude Abbott described ectopia cordis, and Richard Paltauf's remarkable illustrations distinguished the various types of dextrocardia. In 1928, the first useful classification of the cardiac malpositions was proposed, and in 1966, Elliott et al's radiologic classification set the stage for clinical recognition. The first section of this review deals with the 3 basic cardiac malpositions in the presence of bilateral asymmetry. The second section deals with cardiac malpositions in the presence of bilateral left-sidedness or right-sidedness. Previous publications on cardiac malpositions are replete with an arcane vocabulary that confounds rather than clarifies. Even if the terms themselves are understood, inherent complexity weighs against clarity. This review was designed as a guided tour of an unfamiliar subject. PMID:21861958

Perloff, Joseph K

2011-11-01

209

Autotransplantation of the Heart for Primary Cardiac Malignancy  

PubMed Central

Primary cardiac malignancy presents an unusual and difficult surgical challenge. Malignant tumors of the left atrium have proved problematic due to their posterior location and difficulty of surgical exposure. The technique of cardiac explantation, ex vivo resection and cardiac reconstruction, and reimplantation—the cardiac autotransplantation procedure—was developed to solve this anatomic problem. Herein, we discuss the development of this approach and describe the surgical technique. (Tex Heart Inst J 2002;29:105–8) PMID:12075865

Conklin, Lori D.; Reardon, Michael J.

2002-01-01

210

Heart failure caused by congenital left-sided lesions.  

PubMed

There are diverse mechanisms by which congenital left-sided cardiac lesions can precipitate heart failure. Left heart outflow obstruction can impose abnormal pressure load on the left ventricle, inducing adverse remodeling, hypertrophy, and diastolic and systolic dysfunction. Abnormalities in left ventricular inflow can increase pulmonary venous pressure and predisposing to pulmonary edema. In addition, inborn abnormalities in left ventricular myocardial structure and function can impair both systolic and diastolic function and manifest as heart failure later in life. In this article, the different mechanisms, outcomes, and treatments of heart failure in patients with congenital left-sided lesions are discussed. PMID:24275301

Krieger, Eric V; Fernandes, Susan M

2014-01-01

211

Differential Gene Expression of Cardiac Ion Channels in Human Dilated Cardiomyopathy  

PubMed Central

Background Dilated cardiomyopathy (DCM) is characterized by idiopathic dilation and systolic contractile dysfunction of the cardiac chambers. The present work aimed to study the alterations in gene expression of ion channels involved in cardiomyocyte function. Methods and Results Microarray profiling using the Affymetrix Human Gene® 1.0 ST array was performed using 17 RNA samples, 12 from DCM patients undergoing cardiac transplantation and 5 control donors (CNT). The analysis focused on 7 cardiac ion channel genes, since this category has not been previously studied in human DCM. SCN2B was upregulated, while KCNJ5, KCNJ8, CLIC2, CLCN3, CACNB2, and CACNA1C were downregulated. The RT-qPCR (21 DCM and 8 CNT samples) validated the gene expression of SCN2B (p < 0.0001), KCNJ5 (p < 0.05), KCNJ8 (p < 0.05), CLIC2 (p < 0.05), and CACNB2 (p < 0.05). Furthermore, we performed an IPA analysis and we found a functional relationship between the different ion channels studied in this work. Conclusion This study shows a differential expression of ion channel genes involved in cardiac contraction in DCM that might partly underlie the changes in left ventricular function observed in these patients. These results could be the basis for new genetic therapeutic approaches. PMID:24339868

Molina-Navarro, Maria Micaela; Rosello-Lleti, Esther; Ortega, Ana; Tarazon, Estefania; Otero, Manuel; Martinez-Dolz, Luis; Lago, Francisca; Gonzalez-Juanatey, Jose Ramon; Espana, Francisco; Garcia-Pavia, Pablo; Montero, Jose Anastasio; Portoles, Manuel; Rivera, Miguel

2013-01-01

212

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

213

Cardiac nuclear medicine  

SciTech Connect

The book begins with a review of the radionuclide methods available for evaluating cardiac perfusion and function. The authors discuss planar and tomographic thallium myocardial imaging, first-pass and equilibrium radionuclide angiography, and imaging with infarct-avid tracers. Several common but more specialized procedures are then reviewed: nonogemetric measurement of left ventricular volume, phase (Fourier) analysis, stroke volume ratio, right ventricular function, and diastolic function. A separate chapter is devoted to drug interventions and in particular the use of radionuclide ventriculography to monitor doxorubicin toxicity and therapy of congestive heart failure. The subsequent chapters provide a comprehensive guide to test selection, accuracy, and results in acute myocardial infarction, in postmyocardial infarction, in chronic coronary artery disease, before and after medical or surgical revascularization, in valvular heart disease, in cardiomyopathies, and in cardiac trauma.

Gerson, M.C.

1987-01-01

214

Left ventricular noncompaction - a case report.  

PubMed

Left Ventricular (LV) noncompaction is a rare disorder of endomyocardial morphogenesis. It has got a high mortality rate. It is frequently missed during diagnosis because of lack of suspicion and lack of definite diagnostic criteria. We are reporting a case of LV noncompaction in a Bangladeshi patient. Patient presented to us with history of repeated syncope. She had family history of sudden cardiac death. Clinically, there had a systolic murmur in left parasternal area. Her ECG showed different arrhythmia like atrial fibrillation, sinus bradycardia and Ventricular tachycardia. Her echocardiography showed features consistent with 'left ventricular noncompaction'. This is the first case report of this type in a Bangladeshi patient. PMID:25178616

Ullah, M; Hossain, S; Majumder, A S

2014-07-01

215

Cardiac autonomic nerve distribution and arrhythmia?  

PubMed Central

OBJECTIVE: To analyze the distribution characteristics of cardiac autonomic nerves and to explore the correlation between cardiac autonomic nerve distribution and arrhythmia. DATA RETRIEVAL: A computer-based retrieval was performed for papers examining the distribution of cardiac autonomic nerves, using heart, autonomic nerve, sympathetic nerve, vagus nerve, nerve distribution, rhythm and atrial fibrillation as the key words. SELECTION CRITERIA: A total of 165 studies examining the distribution of cardiac autonomic nerve were screened, and 46 of them were eventually included. MAIN OUTCOME MEASURES: The distribution and characteristics of cardiac autonomic nerves were observed, and immunohistochemical staining was applied to determine the levels of tyrosine hydroxylase and acetylcholine transferase (main markers of cardiac autonomic nerve distribution). In addition, the correlation between cardiac autonomic nerve distribution and cardiac arrhythmia was investigated. RESULTS: Cardiac autonomic nerves were reported to exhibit a disordered distribution in different sites, mainly at the surface of the cardiac atrium and pulmonary vein, forming a ganglia plexus. The distribution of the pulmonary vein autonomic nerve was prominent at the proximal end rather than the distal end, at the upper left rather than the lower right, at the epicardial membrane rather than the endocardial membrane, at the left atrium rather than the right atrium, and at the posterior wall rather than the anterior wall. The main markers used for cardiac autonomic nerves were tyrosine hydroxylase and acetylcholine transferase. Protein gene product 9.5 was used to label the immunoreactive nerve distribution, and the distribution density of autonomic nerves was determined using a computer-aided morphometric analysis system. CONCLUSION: The uneven distribution of the cardiac autonomic nerves is the leading cause of the occurrence of arrhythmia, and the cardiac autonomic nerves play an important role in the occurrence, maintenance, and symptoms of arrhythmia.

Liu, Quan; Chen, Dongmei; Wang, Yonggang; Zhao, Xin; Zheng, Yang

2012-01-01

216

Morphology and beyond: CT of cardiac valves  

Microsoft Academic Search

Multi-detector row CT has developed into a valuable tool for noninvasive imaging of the heart. The major indication of cardiac\\u000a CT represents the diagnosis or exclusion of coronary artery disease. Owing to its cross-sectional nature, the same data obtained\\u000a for the coronary arteries contain morpho-anatomical information about the cardiac chambers and valves. When scanning in the\\u000a retrospectively electrocardiography-gated mode, data

Hatem Alkadhi

2008-01-01

217

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. PMID:25047923

2014-01-01

218

A Novel Technique While on Extracorporeal Membrane Oxygenation to Rule Out Anomalous Left Coronary Artery  

Microsoft Academic Search

The authors present an infant who required extracorporeal membrane oxygenation (ECMO) for treatment of cardiac failure. Echocardiography could not conclusively demonstrate the origin of the left coronary artery. To rule out anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) as the etiology of the cardiac failure, angiography was deemed necessary. Given the logistic issues involved in

William R. Wilson; Georgia E. Greer; Joseph D. Tobias

2002-01-01

219

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. PMID:24014420

Neeb, Zachary; Lajiness, Jacquelyn D.; Bolanis, Esther; Conway, Simon J

2014-01-01

220

[Cardiac angiosarcoma].  

PubMed

The paper outlines the authors'case of cardiac angiosarcoma. It provides the gross and microscopic characteristics of this tumor and procedures for its clinical and immunomorphological diagnosis. PMID:21695990

Kir'ianov, N A; Terekhov, M V; Sukhanov, S A; Lozhkin, E A; Nikolaeva, N B

2011-01-01

221

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.

222

Cardiac Cephalalgia  

Microsoft Academic Search

We report a patient with cardiac cephalalgia and review reported cases from the English-language literature based on the new diagnostic criteria published in the International Classification of Headache Disorders, ed 2. Twenty-two patients, including ours, with headaches of cardiac origin were reviewed. The cases fit three of the four new criteria well: Criteria B (acute myocardial ischemia has occurred, 100%),

Shih-Pin Chen; Jong-Ling Fuh; Wen-Chung Yu; Shuu-Jiun Wang

2004-01-01

223

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

224

A cortical potential reflecting cardiac function  

PubMed Central

Emotional trauma and psychological stress can precipitate cardiac arrhythmia and sudden death through arrhythmogenic effects of efferent sympathetic drive. Patients with preexisting heart disease are particularly at risk. Moreover, generation of proarrhythmic activity patterns within cerebral autonomic centers may be amplified by afferent feedback from a dysfunctional myocardium. An electrocortical potential reflecting afferent cardiac information has been described, reflecting individual differences in interoceptive sensitivity (awareness of one's own heartbeats). To inform our understanding of mechanisms underlying arrhythmogenesis, we extended this approach, identifying electrocortical potentials corresponding to the cortical expression of afferent information about the integrity of myocardial function during stress. We measured changes in cardiac response simultaneously with electroencephalography in patients with established ventricular dysfunction. Experimentally induced mental stress enhanced cardiovascular indices of sympathetic activity (systolic blood pressure, heart rate, ventricular ejection fraction, and skin conductance) across all patients. However, the functional response of the myocardium varied; some patients increased, whereas others decreased, cardiac output during stress. Across patients, heartbeat-evoked potential amplitude at left temporal and lateral frontal electrode locations correlated with stress-induced changes in cardiac output, consistent with an afferent cortical representation of myocardial function during stress. Moreover, the amplitude of the heartbeat-evoked potential in the left temporal region reflected the proarrhythmic status of the heart (inhomogeneity of left ventricular repolarization). These observations delineate a cortical representation of cardiac function predictive of proarrhythmic abnormalities in cardiac repolarization. Our findings highlight the dynamic interaction of heart and brain in stress-induced cardiovascular morbidity. PMID:17420478

Gray, Marcus A.; Taggart, Peter; Sutton, Peter M.; Groves, David; Holdright, Diana R.; Bradbury, David; Brull, David; Critchley, Hugo D.

2007-01-01

225

Facts about Hypoplastic Left Heart Syndrome  

MedlinePLUS

... ventricle becomes the main pumping chamber to the body. These surgeries do not cure hypoplastic left heart syndrome, but ... both the lungs and the rest of the body. This can be a very challenging surgery. After this procedure, an infantâ??s skin still might ...

226

Anomalous left coronary artery arising from the left pulmonary artery, aortic coarctation, and a large ventricular septal defect  

Microsoft Academic Search

e describe a case of large ventricular septal defect (VSD), coarctation of the aorta, anomalous left coronary artery arising from the left pulmonary artery (ALCALPA), and congenital diaphrag- matic hernia that was successfully managed surgically. Literature search revealed no report of a similar condition. Clinical Summary A baby girl was found to have a right-sided diaphragmatic hernia antenatally. Fetal cardiac

John Santosh; Kumar Murala; Steven Cooper; Barry Duffy; Elizabeth Argent; Graham Nunn

227

Anomalous Origin of Left Coronary Artery From Pulmonary Artery: Recovery of Left Ventricular Function After Dual Coronary Repair  

Microsoft Academic Search

Objectives. We reviewed our institutional experience with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) after dual coronary repair to assess preoperative variables predictive of outcome, the time course for postoperative recovery of cardiac function, the short- and long-term complications and our experience with left ventricular assist devices (LVAD) in these patients.Background. Outcome after surgical repair

Marcy L Schwartz; Richard A Jonas; Steven D Colan

1997-01-01

228

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. PMID:24570863

Hong, Seong Wook

2014-01-01

229

Oxytocin in cardiac ontogeny  

PubMed Central

Previous studies demonstrated the presence of oxytocin (OT) and oxytocin receptors (OTRs) in the heart. The present work provides results supporting a potential role of OT in cardiomyogenesis. Here, we show a maximal OT and OTR protein level in the developing rat heart at day 21 of gestation and postnatal days 1-4, when cardiac myocytes are at a stage of intense hyperplasia. Between postnatal days 1 and 66, OT decreased linearly in all heart chambers (4.1- to 6.6-fold). Correspondingly, immunocytochemistry demonstrated that OTRs, which were eminent in postnatal cardiomyocytes, declined with age to low levels in adults. Interestingly, in coronary vasculature, OTRs developed in endothelial cells at postnatal days 12 and 22 and achieved a plateau in adult rats. These findings suggest that OT can be involved in developmental formation of the coronary vessels. In vivo, the OT/OTR system in the fetal heart was sensitive to the actions of retinoic acid (RA), recognized as a major cardiac morphogen. RA treatment produced a significant increase (2- to 3-fold) both in the OT concentration and in the OT mRNA levels. Ex vivo, an OT antagonist inhibited RA-mediated cardiomyocyte differentiation of P19 embryonic stem cells. The decline of cardiac OT expression from infancy to adulthood of the rat and changes in cell types expressing OTR indicate a dynamic regulation of the OT system in the heart rather than constitutive expression. The results support the hypothesis that RA induces cardiomyogenesis by activation of the cardiac OT system. PMID:15316117

Jankowski, Marek; Danalache, Bogdan; Wang, Donghao; Bhat, Pangala; Hajjar, Fadi; Marcinkiewicz, Mieczyslaw; Paquin, Joanne; McCann, Samuel M.; Gutkowska, Jolanta

2004-01-01

230

Oxytocin in cardiac ontogeny.  

PubMed

Previous studies demonstrated the presence of oxytocin (OT) and oxytocin receptors (OTRs) in the heart. The present work provides results supporting a potential role of OT in cardiomyogenesis. Here, we show a maximal OT and OTR protein level in the developing rat heart at day 21 of gestation and postnatal days 1-4, when cardiac myocytes are at a stage of intense hyperplasia. Between postnatal days 1 and 66, OT decreased linearly in all heart chambers (4.1- to 6.6-fold). Correspondingly, immunocytochemistry demonstrated that OTRs, which were eminent in postnatal cardiomyocytes, declined with age to low levels in adults. Interestingly, in coronary vasculature, OTRs developed in endothelial cells at postnatal days 12 and 22 and achieved a plateau in adult rats. These findings suggest that OT can be involved in developmental formation of the coronary vessels. In vivo, the OT/OTR system in the fetal heart was sensitive to the actions of retinoic acid (RA), recognized as a major cardiac morphogen. RA treatment produced a significant increase (2- to 3-fold) both in the OT concentration and in the OT mRNA levels. Ex vivo, an OT antagonist inhibited RA-mediated cardiomyocyte differentiation of P19 embryonic stem cells. The decline of cardiac OT expression from infancy to adulthood of the rat and changes in cell types expressing OTR indicate a dynamic regulation of the OT system in the heart rather than constitutive expression. The results support the hypothesis that RA induces cardiomyogenesis by activation of the cardiac OT system. PMID:15316117

Jankowski, Marek; Danalache, Bogdan; Wang, Donghao; Bhat, Pangala; Hajjar, Fadi; Marcinkiewicz, Mieczyslaw; Paquin, Joanne; McCann, Samuel M; Gutkowska, Jolanta

2004-08-31

231

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

232

About Cardiac Arrest  

MedlinePLUS

... High Blood Pressure Tools & Resources Stroke More About Cardiac Arrest Updated:Sep 10,2014 What is cardiac arrest? ... to heart disease and stroke. Start exploring today ! Cardiac Arrest • Home • About Cardiac Arrest • Understand Your Risk for ...

233

Anomalous left anterior descending artery to coronary sinus fistula with associated localized ischemia: A clinical dilemma  

PubMed Central

Patient: Female, 57 Final Diagnosis: Coronary sinus – venous fistula Symptoms: Dispnoea Medication: — Clinical Procedure: — Specialty: Cardiology Objective: Rare disease Background: Coronary arterial fistula, or arteriovenous malformation (AVM), is a connection between the coronary tree and a cardiac chamber or great vessel, having bypassed the myocardial capillary bed. Known complications from coronary artery fistulas may include “steal” from the adjacent myocardium, resulting in myocardial ischemia. Case Report: We report the case of a 57-year-old Hispanic woman with abnormal preoperative electrocardiogram (ECG) and symptoms of dyspnea on exertion, who underwent a stress echocardiography demonstrating inferior distribution hypokinesis at peak exercise. Coronary computed tomography angiography (CCTA) demonstrated a venous fistula connecting the coronary sinus (CS) with the distal portion of the left anterior descending artery (LAD), occupying the territory of a left posterior descending artery (L-PDA) and corresponding in distribution with the patient’s stress-induced wall motion abnormalities. Conclusions: Anomalous left anterior descending artery to coronary sinus fistula with associated ischemia is a rare clinical dilemma with limited experience of success with either surgical or medical options. PMID:24644528

Russo, Frank D.; Ahmadian, Homayoun R.; Slim, Ahmad M.

2014-01-01

234

Left heart ventricular angiography  

MedlinePLUS

... left side of the heart and, sometimes, the coronary arteries. ... Angiography - left heart; Left ventriculography ... side of the heart or the heart valves. Coronary angiography may be needed when blockage of the coronary ...

235

An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET  

NASA Astrophysics Data System (ADS)

Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6? ± ?3.3?mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4?ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3? ± ?1.3?mm) compared to cardiac-gated images (11.3? ± ?1.3?mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes.

Koivumäki, Tuomas; Nekolla, Stephan G.; Fürst, Sebastian; Loher, Simone; Vauhkonen, Marko; Schwaiger, Markus; Hakulinen, Mikko A.

2014-10-01

236

An integrated bioimpedance-ECG gating technique for respiratory and cardiac motion compensation in cardiac PET.  

PubMed

Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6? ± ?3.3?mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4?ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3? ± ?1.3?mm) compared to cardiac-gated images (11.3? ± ?1.3?mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes. PMID:25295531

Koivumäki, Tuomas; Nekolla, Stephan G; Fürst, Sebastian; Loher, Simone; Vauhkonen, Marko; Schwaiger, Markus; Hakulinen, Mikko A

2014-10-01

237

Cardiac Regeneration  

PubMed Central

The heart is a pump that is comprised of cardiac myocytes and other cell types and whose proper function is critical to quality of life. The ability to trigger regeneration of heart muscle following injury eludes adult mammals, a deficiency of great clinical impact. Major research efforts are attempting to change this through advances in cell therapy or activating endogenous regenerative mechanisms that exist only early in life. By contrast with mammals, lower vertebrates like zebrafish demonstrate an impressive natural capacity for cardiac regeneration throughout life. This review will cover recent progress in the field of heart regeneration with a focus on endogenous regenerative capacity and its potential manipulation. PMID:22449849

Choi, Wen-Yee; Poss, Kenneth D.

2012-01-01

238

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

239

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 heart transplant or a lung transplant Angina Heart failure The ...

240

Hypoxia training attenuates left ventricular remodeling in rabbit with myocardial infarction  

PubMed Central

Objective Previous studies showed that hypoxia preconditioning could protect cardiac function against subsequent myocardial infarction injury. However, the effect of hypoxia on left ventricular after myocardial infarction is still unclear. This study therefore aims to investigate the effects of hypoxia training on left ventricular remodeling in rabbits post myocardial infarction. Methods Adult male rabbits were randomly divided into three groups: group SO (sham operated), group MI (myocardial infarction only) and group MI-HT (myocardial infarction plus hypoxia training). Myocardial infarction was induced by left ventricular branch ligation. Hypoxia training was performed in a hypobaric chamber (having equivalent condition at an altitude of 4000 m, FiO214.9%) for 1 h/day, 5 days/week for four weeks. At the endpoints, vascular endothelial growth factor (VEGF) in the plasma was measured. Infarct size and capillary density were detected by histology. Left ventricular remodeling and function were assessed by echocardiography. Results After the 4-week experiment, compared with the group SO, plasma VEGF levels in groups MI (130.27 ± 18.58 pg/mL, P < 0.01) and MI-HT (181.93 ± 20.29 pg/mL, P < 0.01) were significantly increased. Infarct size in Group MI-HT (29.67% ± 7.73%) was deceased remarkably, while its capillary density (816.0 ± 122.2/mm2) was significantly increased. For both groups MI and MI-HT, left ventricular end-diastolic and end-systolic dimensions were increased whereas left ventricular ejection fraction was decreased. However, compared with group MI, group MI-HT diminished left ventricular end-diastolic (15.86 ± 1.09 mm, P < 0.05) and end-systolic dimensions (12.10 ± 1.20 mm, P < 0.01) significantly and improved left ventricular ejection fraction (54.39 ± 12.74 mm, P < 0.05). Conclusion Hypoxia training may improve left ventricular function and reduce remodeling via angiogenesis in rabbits with MI. PMID:25278973

Wan, Chun-Xiao; Lan, Yun-Feng; Jiang, Hui; Huang, Jie; Li, Rui-Sheng; Bi, Sheng; Li, Jian-An

2014-01-01

241

Hypoplastic left heart syndrome secondary to intrauterine rhabdomyoma necessitating single ventricle palliation  

PubMed Central

Rhabdomyoma, a benign hamartomatous tumor of the cardiac embryonic myocyte, is the most common intrauterine cardiac tumor and accounts for 0.12% of prenatal fetal studies. Fetal cardiac rhabdomyomas increase in size during second and early third trimester and spontaneously regress postnatally. The clinical presentation is usually benign, however, compromise of the ventricular outflow tract leading to decreased cardiac output and fetal death have been reported. We present a case of large cardiac rhabdomyoma in a fetus that might have caused complete left ventricular outflow tract obstruction and development of hypoplastic left heart syndrome (HLHS) necessitating postnatal single ventricle palliation therapy. The clinical course and outcomes of prenatally diagnosed cardiac rhabdomyoma are reviewed and theories of the development of hypoplastic left heart syndrome are explored.

Mir, Arshid; Ikemba, Catherine Minor; Veeram Reddy, Surendranath R

2014-01-01

242

Hypoplastic left heart syndrome secondary to intrauterine rhabdomyoma necessitating single ventricle palliation.  

PubMed

Rhabdomyoma, a benign hamartomatous tumor of the cardiac embryonic myocyte, is the most common intrauterine cardiac tumor and accounts for 0.12% of prenatal fetal studies. Fetal cardiac rhabdomyomas increase in size during second and early third trimester and spontaneously regress postnatally. The clinical presentation is usually benign, however, compromise of the ventricular outflow tract leading to decreased cardiac output and fetal death have been reported. We present a case of large cardiac rhabdomyoma in a fetus that might have caused complete left ventricular outflow tract obstruction and development of hypoplastic left heart syndrome (HLHS) necessitating postnatal single ventricle palliation therapy. The clinical course and outcomes of prenatally diagnosed cardiac rhabdomyoma are reviewed and theories of the development of hypoplastic left heart syndrome are explored. PMID:25298697

Mir, Arshid; Ikemba, Catherine Minor; Veeram Reddy, Surendranath R

2014-09-01

243

Left-symmetric algebroids  

E-print Network

In this paper, we introduce a notion of a left-symmetric algebroid, which is a generalization of a left-symmetric algebra from a vector space to a vector bundle. The left multiplication gives rise to a representation of the corresponding sub-adjacent Lie algebroid. We construct left-symmetric algebroids from $\\mathcal O$-operators on Lie algebroids. We study phase spaces of Lie algebroids in terms of left-symmetric algebroids. Representations of left-symmetric algebroids are studied in detail. At last, we study deformations of left-symmetric algebroids, which could be controlled by the second cohomology class in the deformation cohomology.

Jiefeng Liu; Yunhe Sheng; Chengming Bai; Zhiqi Chen

2013-12-23

244

Proven cardiac changes during death-feigning (tonic immobility) in rabbits (Oryctolagus cuniculus).  

PubMed

Tonic immobility (TI) is a response to fear or threat by remaining motionless, principally when attacked by predators from which there is no possibility of escape. Thus, here we demonstrate a way of easily reproducing this phenomenon in a laboratory setting and characterize the cardiac electromechanical alterations during TI. We observed a significant decrease in heart rate (HR) and changes of rhythm in electrocardiogram during TI in rabbits. Echocardiogram showed a significant increase in the left ventricle chamber diameter during systole and a consequent decrease in fractional shortening and ejection fraction, in addition to the HR and rhythm changes. There was also a significant decrease in aortic and pulmonary artery blood flow. Diastolic functional changes included a significant decrease of the peak atrial contraction velocity (A peak) and consequent increase in the ratio of peak early diastolic velocity to A peak and increased isovolumetric relaxation time. We were able to prove that TI changes the cardiac function considerably. Although the "fight-or-flight" response is the most common response to fear, which is characterized by the action of sympathetic nervous system with tachycardia and increased physical activity, TI is an alternative anti-predator behavior causing cardiac changes opposite to the "fight-or-flight" phenomenon. PMID:24515628

Giannico, Amália Turner; Lima, Leandro; Lange, Rogério Ribas; Froes, Tilde Rodrigues; Montiani-Ferreira, Fabiano

2014-04-01

245

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

246

Static diffusion cloud chambers  

NASA Astrophysics Data System (ADS)

The chamber geometry and optical arrangement are described. The supersaturation range is given and consists of readings taken at five fixed points: 0.25%, 0.5%, 0.75%, 1.0%, and 1.25%. The detection system is described including light source, cameras, and photocell detectors. The temperature control and the calibration of the chamber are discussed.

Ayers, G.

1981-11-01

247

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

248

Semiconductor drift chambers  

SciTech Connect

Semiconductor drift chambers for position and energy measurements have been invented, built and tested. A short 'Ccount is here given on the principles of the drift chamber and on the experimental results. Detailed reports have been written on the quoted bibliography and new reports will be published shortly.

Lutz, G.; Goulding, F.; Luke, P.N.; Madden, N.W.; Waltor, J.; Wylie, A.

1985-04-01

249

IEEE TRANSACTIONS ON MEDICAL IMAGING 1 Four-Chamber Heart Modeling and Automatic  

E-print Network

-chamber heart seg- mentation system for the quantitative functional analysis of the heart from cardiac computed about the heart chambers, large vessels, and coronary arter- ies [1]. Therefore, CT is an important must be obtained from the IEEE by sending a request to pubs-permissions@ieee.org. quantitative

Barbu, Adrian

250

Left Ventricular Septal Aneurysm in Association with Bicuspid Aortic ValveA Case Report  

Microsoft Academic Search

Diverticula of the left ventricle are rare cardiac anomalies. Most cases arise from the apex of the left ventricle and are usually found in children. Only a few cases have been documented in adults. The authors report a case of a 38-year-old woman who presented with dyspnea and chest pain. She was found to have a septal left ventricular diverticulum

Aylin Yildirir; Mustafa Kemal Batur; Giray Kabakci

2001-01-01

251

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

252

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

253

Reproducibility of cine displacement encoding with stimulated echoes (DENSE) cardiovascular magnetic resonance for measuring left ventricular strains, torsion, and synchrony in mice  

PubMed Central

Background Advanced measures of cardiac function are increasingly important to clinical assessment due to their superior diagnostic and predictive capabilities. Cine DENSE cardiovascular magnetic resonance (CMR) is ideal for quantifying advanced measures of cardiac function based on its high spatial resolution and streamlined post-processing. While many studies have utilized cine DENSE in both humans and small-animal models, the inter-test and inter-observer reproducibility for quantification of advanced cardiac function in mice has not been evaluated. This represents a critical knowledge gap for both understanding the capabilities of this technique and for the design of future experiments. We hypothesized that cine DENSE CMR would show excellent inter-test and inter-observer reproducibility for advanced measures of left ventricular (LV) function in mice. Methods Five normal mice (C57BL/6) and four mice with depressed cardiac function (diet-induced obesity) were imaged twice, two days apart, on a 7T ClinScan MR system. Images were acquired with 15–20 frames per cardiac cycle in three short-axis (basal, mid, apical) and two long-axis orientations (4-chamber and 2-chamber). LV strain, twist, torsion, and measures of synchrony were quantified. Images from both days were analyzed by one observer to quantify inter-test reproducibility, while inter-observer reproducibility was assessed by a second observer’s analysis of day-1 images. The coefficient of variation (CoV) was used to quantify reproducibility. Results LV strains and torsion were highly reproducible on both inter-observer and inter-test bases with CoVs???15%, and inter-observer reproducibility was generally better than inter-test reproducibility. However, end-systolic twist angles showed much higher variance, likely due to the sensitivity of slice location within the sharp longitudinal gradient in twist angle. Measures of synchrony including the circumferential (CURE) and radial (RURE) uniformity of strain indices, showed excellent reproducibility with CoVs of 1% and 3%, respectively. Finally, peak measures (e.g., strains) were generally more reproducible than the corresponding rates of change (e.g., strain rate). Conclusions Cine DENSE CMR is a highly reproducible technique for quantification of advanced measures of left ventricular cardiac function in mice including strains, torsion and measures of synchrony. However, myocardial twist angles are not reproducible and future studies should instead report torsion. PMID:23981339

2013-01-01

254

Cardiac optogenetics  

PubMed Central

Optogenetics is an emerging technology for optical interrogation and control of biological function with high specificity and high spatiotemporal resolution. Mammalian cells and tissues can be sensitized to respond to light by a relatively simple and well-tolerated genetic modification using microbial opsins (light-gated ion channels and pumps). These can achieve fast and specific excitatory or inhibitory response, offering distinct advantages over traditional pharmacological or electrical means of perturbation. Since the first demonstrations of utility in mammalian cells (neurons) in 2005, optogenetics has spurred immense research activity and has inspired numerous applications for dissection of neural circuitry and understanding of brain function in health and disease, applications ranging from in vitro to work in behaving animals. Only recently (since 2010), the field has extended to cardiac applications with less than a dozen publications to date. In consideration of the early phase of work on cardiac optogenetics and the impact of the technique in understanding another excitable tissue, the brain, this review is largely a perspective of possibilities in the heart. It covers the basic principles of operation of light-sensitive ion channels and pumps, the available tools and ongoing efforts in optimizing them, overview of neuroscience use, as well as cardiac-specific questions of implementation and ideas for best use of this emerging technology in the heart. PMID:23457014

2013-01-01

255

Cardiac Surgery  

PubMed Central

Well into the first decades of the 20th century, medical opinion held that any surgical attempts to treat heart disease were not only misguided, but unethical. Despite such reservations, innovative surgeons showed that heart wounds could be successfully repaired. Then, extracardiac procedures were performed to correct patent ductus arteriosus, coarctation of the aorta, and tetralogy of Fallot. Direct surgery on the heart was accomplished with closed commissurotomy for mitral stenosis. The introduction of the heart-lung machine and cardiopulmonary bypass enabled the surgical treatment of other congenital and acquired heart diseases. Advances in aortic surgery paralleled these successes. The development of coronary artery bypass grafting greatly aided the treatment of coronary heart disease. Cardiac transplantation, attempts to use the total artificial heart, and the application of ventricular assist devices have brought us to the present day. Although progress in the field of cardiovascular surgery appears to have slowed when compared with the halcyon times of the past, substantial challenges still face cardiac surgeons. It can only be hoped that sufficient resources and incentive can carry the triumphs of the 20th century into the 21st. This review covers past developments and future opportunities in cardiac surgery. PMID:22163121

Weisse, Allen B.

2011-01-01

256

Calcified amorphous tumor in left atrium presenting with cerebral infarction  

PubMed Central

Calcified amorphous tumor (CAT) of the heart is an extremely rare cardiac mass. We describe a case of cardiac CAT in a 70-year-old Korean female who presented with acute onset dysarthria and right side weakness. Echocardiography and chest computed tomography revealed a left atrial mass that originated from the interatrial septum. The patient underwent surgical resection and pathologic examination demonstrated CAT. Postoperative course was uneventful and she was followed without recurrence.

Suh, Jong Hui; Kwon, Jong Bum; Park, Kuhn

2014-01-01

257

Calcified amorphous tumor in left atrium presenting with cerebral infarction.  

PubMed

Calcified amorphous tumor (CAT) of the heart is an extremely rare cardiac mass. We describe a case of cardiac CAT in a 70-year-old Korean female who presented with acute onset dysarthria and right side weakness. Echocardiography and chest computed tomography revealed a left atrial mass that originated from the interatrial septum. The patient underwent surgical resection and pathologic examination demonstrated CAT. Postoperative course was uneventful and she was followed without recurrence. PMID:25276375

Suh, Jong Hui; Kwon, Jong Bum; Park, Kuhn; Park, Chan Beom

2014-09-01

258

Hypoplastic left heart syndrome: parent support for early decision making.  

PubMed

Hypoplastic left heart syndrome is a life threatening congenital cardiac anomaly. After a child has been diagnosed with hypoplastic left heart syndrome, parents must make life or death decisions within days of birth. Healthcare providers must provide appropriate education so that parents are able to make informed, timely decisions. Information regarding the diagnosis, treatment options, and parental decision making process for initial decision making for hypoplastic left heart syndrome are provided to guide nurses who work with these families. The challenging decision making process that parents must go through after diagnosis of hypoplastic left heart syndrome will be described. PMID:23246301

Toebbe, Sarah; Yehle, Karen; Kirkpatrick, Jane; Coddington, Jennifer

2013-01-01

259

Multiple cerebral aneurysms as manifestations of cardiac myxoma: Brain imaging, digital subtraction angiography, and echocardiography  

Microsoft Academic Search

We report a patient with left side atrial myxoma who initially presented with neurological symptoms. Cerebral magnetic resonance imaging and angiography revealed multiple aneurysms with enhancement leading to the final diagnosis of cardiac myxoma. We showed distinctive findings from brain magnetic resonance imaging, digital subtraction angiography, and cardiac echography and the final pathological appearance of cardiac myxoma in this patient.

Kuo-Hsien Chiang; Hua-Ming Cheng; Bee-Song Chang; Cheng-Hui Chiu; Pao-Sheng Yen

2011-01-01

260

Cardiac nociceptive reflexes after transmyocardial laser revascularization: Implications for the neural hypothesis of angina relief  

Microsoft Academic Search

Objective: The mechanism by which transmyocardial laser revascularization relieves angina is not understood. One theory is that laser-induced thermal damage to cardiac nerves results in cardiac denervation. This study examined the acute effects of transmyocardial laser revascularization on reflex responses mediated by cardiac nociceptors, the left ventricular receptors with sympathetic afferent fibers that are thought to mediate anginal chest pain.

Anthony J. Minisi; On Topaz; M. Susan Quinn; Laxmi B. Mohanty

2001-01-01

261

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

262

The cost-utility of left ventricular assist devices for end-stage heart failure patients ineligible for cardiac transplantation: a systematic review and critical appraisal of economic evaluations  

PubMed Central

Background A health technology assessment (HTA) of left ventricular assist devices (LVADs) as destination therapy in patients with end-stage heart failure was commissioned by the Dutch Health Care Insurance Board [College voor Zorgverzekeringen (CVZ)]. In this context, a systematic review of the economic literature was performed to assess the procedure’s value for money. Methods A systematic search (updated in December 2013) for economic evaluations was performed by consulting various databases: the HTA database produced by the Centre for Reviews and Dissemination (CRD HTA), websites of HTA institutes, CRD’s National Health Service Economic Evaluation Database (NHS EED), Medline (OVID) and EMBASE. No time or language restrictions were imposed and pre-defined selection criteria were used. The two-step selection procedure was performed by two people. References of the selected studies were checked for additional relevant citations. Results Six relevant studies were selected. Four economic evaluations relied on the results of the REMATCH trial to compare a pulsatile-flow LVAD with optimal medical therapy (OMT). These evaluations were performed before the publication of the HeartMate II (HM-II) Destination Therapy Trial which compared a pulsatile-flow with a continuous-flow LVAD. Two more recent economic evaluations combined the results of both trials to make an indirect comparison of a continuous-flow LVAD with OMT. In all studies, the largest part of the incremental cost was due to the reimplantation cost of an LVAD, with a device cost of €58,000-€75,000 and about €55,000 for the surgical procedure. The survival gain was highest with a continuous-flow LVAD, up to about three life-years gained (LYG) versus OMT in the most optimistic study. Quality of life (QoL) was improved but measures with a generic utility instrument were lacking, making estimates on quality-adjusted life-years (QALYs) gained more uncertain. Incremental cost-effectiveness ratios of the two most recent studies were on average €107,600 and $198,184 (ca.€145,800) per QALY gained. Conclusions Although LVAD destination therapy improves survival and QoL, it remains questionable as to whether it offers value for money. This conclusion may alter if the price of the device/procedure decreases sufficiently, in combination with further improved outcomes for mortality, adverse events and QoL.

Van den Bruel, Ann; Smit, Yolba; De Jonge, Nicolaas; Vlayen, Joan

2014-01-01

263

Post-exercise left ventricular dysfunction measured after a long-duration cycling event  

PubMed Central

Background In this research, an extension to our previous work published in the Clinical Journal of Sports Medicine in 2009, we studied subjects that differed in terms of age and training status and assessed the impact of prolonged exercise on systolic and left ventricular diastolic function and cardiac biomarkers levels, recognized as identifiers of cardiac damage and dysfunction. We also assessed the possible influence of event duration, exercise intensity and weight loss (dehydration) on left ventricular diastolic function. Findings Ninety-one male cyclists were assessed by echocardiography and serum biomarkers before and after the 2005 Quebrantahuesos cycling event (206 km long and with an accumulated slope of 3800 m). Cardiac function was assessed by echocardiography and cardiac biomarkers were assessed in blood serum. Echocardiograms measured left ventricular internal dimension during diastole and systole, left ventricular posterior wall thickness during diastole, interventricular septum thickness during diastole, left ventricular ejection fraction and diastolic filling. The heart rate of 50 cyclists was also monitored during the race to evaluate exercise intensity. Echocardiograph results indicated that left ventricular diastolic and systolic function decreased after the race, with systolic function reduced to a significant degree. Left ventricular ejection fraction was below 55% in 29 cyclists. The decrease in left ventricular systolic and diastolic function did not correlate with age, training status, race duration, weight loss or exercise intensity. Conclusions Left ventricular systolic and diastolic function was reduced and cardiac biomarkers were increased after the cycling event, but the mechanisms behind such outcomes remain unclear. PMID:23706119

2013-01-01

264

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...

265

Mercury Chamber Considerations  

E-print Network

Mercury Chamber Considerations V. Graves IDS-NF Target Studies July 2011 #12;2 Managed by UT-Battelle for the U.S. Department of Energy Mercury Chamber Considerations, July 2011 Flow Loop Review · 1 cm dia nozzle, 20 m/s jet requires 1.57 liter/sec mercury flow (94.2 liter/min, 24.9 gpm). · MERIT experiment

McDonald, Kirk

266

Multislice CT imaging of ruptured left sinus of Valsalva aneurysm with fistulous track between left sinus and right atrium.  

PubMed

Sinus of valsalva aneurysm is a rare condition arising from any of the three aortic sinuses. Among them, an aneurysm arising from the left coronary sinus is the rarest. Most of these cases were earlier diagnosed using echocardiography and conventional angiography. But with the availability of advanced imaging modalities like 64 slice cardiac CT and MR modalities, this condition can be accurately assessed noninvasively. We report a case of ruptured aneurysm originating from the left coronary sinus with a long windsock type of fistulous track between the aneurysm and right atrium evaluated by 64 slice cardiac CT imaging. This was later confirmed perioperatively. PMID:22470808

Pampapati, Praveenkumar; Rao, Hejmadi Tati Gururaj; Radhesh, Srinivasan; Anand, Hejjaji Krishnamurthy; Praveen, Lokkur Srinivasamurthy

2011-01-01

267

Depiction of ruptured sinus of Valsalva aneurysms by cardiac computed tomography angiography  

PubMed Central

Ruptured sinus of Valsalva aneurysm is an uncommon condition with variable manifestation that results in aortocardiac shunt. The presentation may range from an asymptomatic murmur to cardiogenic shock. The initial diagnosis is established or suspected by two-dimensional echocardiography and colour flow Doppler. Transesophageal echocardiography is especially helpful in delineating the anatomy of the aneurysm and its connections to other chambers. The gold standard diagnostic method for ruptured sinus of Valsalva aneurysm is cardiac catheterization and aortography. Recent reports have suggested a potential role of cardiac computed tomography in establishing diagnosis in such cases. The high spatial resolution of cardiac computed tomography provides anatomical details of the ruptured aneurysm by depicting a jet of contrast materials extending from the aneurysm and adjacent cardiac chamber. In addition, cardiac computed tomography provides a comprehensive cardiac evaluation including coronary artery anatomy, and the presence of other associated cardiac or vascular anomalies. PMID:23620709

Fathala, Ahmed

2012-01-01

268

Depiction of ruptured sinus of Valsalva aneurysms by cardiac computed tomography angiography.  

PubMed

Ruptured sinus of Valsalva aneurysm is an uncommon condition with variable manifestation that results in aortocardiac shunt. The presentation may range from an asymptomatic murmur to cardiogenic shock. The initial diagnosis is established or suspected by two-dimensional echocardiography and colour flow Doppler. Transesophageal echocardiography is especially helpful in delineating the anatomy of the aneurysm and its connections to other chambers. The gold standard diagnostic method for ruptured sinus of Valsalva aneurysm is cardiac catheterization and aortography. Recent reports have suggested a potential role of cardiac computed tomography in establishing diagnosis in such cases. The high spatial resolution of cardiac computed tomography provides anatomical details of the ruptured aneurysm by depicting a jet of contrast materials extending from the aneurysm and adjacent cardiac chamber. In addition, cardiac computed tomography provides a comprehensive cardiac evaluation including coronary artery anatomy, and the presence of other associated cardiac or vascular anomalies. PMID:23620709

Fathala, Ahmed

2012-09-01

269

Autologous heart cell transplantation improves cardiac function after myocardial injury  

Microsoft Academic Search

Background. Fetal ventricular cardiomyocyte transplantation into a cardiac scar improved ventricular function, but these cells were eventually eliminated by rejection. We therefore examined the feasibility of autologous adult heart cell transplantation.Methods. A transmural scar was produced in the left ventricular free wall of adult rats by cryoinjury. The left atrial appendage was harvested, and the atrial heart cells were cultured

Tetsuro Sakai; Ren-Ke Li; Richard D Weisel; Donald A. G Mickle; Eung-Joong Kim; Shinji Tomita; Zhi-Qian Jia; Terrence M Yau

1999-01-01

270

Appearance of recurrent cardiac myxofibrosarcoma on FDG PET/CT.  

PubMed

Primary cardiac sarcomas are extremely rare tumors. In this case report, we presented the condition of a 37-year-old male patient diagnosed with myxofibrosarcoma after histopathologic evaluation of the left atrium mass excision. FDG PET/CT was performed and showed recurrent hypermetabolic lesions in the left atrial wall and right anterior mediastinal region. PMID:24662649

Erdo?an, Ezgi Basak; Asa, Sertac; Aksoy, Sabire Yilmaz; Ozhan, Meftune; Halac, Metin

2014-06-01

271

Cardiac sympathetic afferent denervation attenuates cardiac remodeling and improves cardiovascular dysfunction in rats with heart failure.  

PubMed

The enhanced cardiac sympathetic afferent reflex (CSAR) contributes to the exaggerated sympathoexcitation in chronic heart failure (CHF). Increased sympathoexcitation is positively related to mortality in patients with CHF. However, the potential beneficial effects of chronic CSAR deletion on cardiac and autonomic function in CHF have not been previously explored. Here, we determined the effects of chronic CSAR deletion on cardiac remodeling and autonomic dysfunction in CHF. To delete the transient receptor potential vanilloid 1 receptor-expressing CSAR afferents selectively, epicardial application of resiniferatoxin (50 ?g/mL), an ultrapotent analog of capsaicin, was performed during myocardium infarction surgery in rats. This procedure largely abolished the enhanced CSAR, prevented the exaggerated renal and cardiac sympathetic nerve activity and improved baroreflex sensitivity in CHF rats. Most importantly, we found that epicardial application of resiniferatoxin largely prevented the elevated left ventricle end-diastolic pressure, lung edema, and cardiac hypertrophy, partially reduced left ventricular dimensions in the failing heart, and increased cardiac contractile reserve in response to ?-adrenergic receptor stimulation with isoproterenol in CHF rats. Molecular evidence showed that resiniferatoxin attenuated cardiac fibrosis and apoptosis and reduced expression of fibrotic markers and transforming growth factor-? receptor I in CHF rats. Pressure-volume loop analysis showed that resiniferatoxin reduced the end-diastolic pressure volume relationships in CHF rats, indicating improved cardiac compliance. In summary, cardiac sympathetic afferent deletion exhibits protective effects against deleterious cardiac remodeling and autonomic dysfunction in CHF. These data suggest a potential new paradigm and therapeutic potential in the management of CHF. PMID:24980663

Wang, Han-Jun; Wang, Wei; Cornish, Kurtis G; Rozanski, George J; Zucker, Irving H

2014-10-01

272

Communication between the left ventricle and right atrium  

PubMed Central

A further 15 patients with left ventricular/right atrial communication are reported, 14 of whom were treated surgically. The clinical triad of a ventricular septal defect murmur, cardiac enlargement, and an arteriovenous shunt at atrial level is characteristic of the malformation. Of the 14 patients accorded surgical treatment, one died soon after operation. The remainder are well, with both the electrocardiographic signs of left ventricular hypertrophy and the radiographic evidence of cardiomegaly having undergone regression. Images PMID:4227847

Barclay, R. S.; Reid, J. M.; Coleman, E. N.; Stevenson, J. G.; Welsh, T. M.; McSwan, N.

1967-01-01

273

Cardiac Arrhythmia Detection By ECG Feature Extraction  

NASA Astrophysics Data System (ADS)

Electrocardiogram (ECG) is a noninvasive technique used as a primary diagnostic tool for detecting cardiovascular diseases. One of the important cardiovascular diseases is cardiac arrhythmia. Computer-assisted cardiac arrhythmia detection and classification can play a significant role in the management of cardiac disorders. This paper presents an algorithm developed using Python 2.6 simulation tool for the detection of cardiac arrhythmias e.g. premature ventricular contracture (PVC), right bundle branch block (R or RBBB) and left bundle branch block (L or LBBB) by extracting various features and vital intervals (i.e. RR, QRS, etc) from the ECG waveform. The proposed method was tested over the MIT-BIH Arrhythmias Database.

Mane, Rameshwari S.; Cheeran, A. N.; Awandekar, Vaibhav D.; Rani, Priya

2013-03-01

274

Cardiac asthma: new insights into an old disease.  

PubMed

Cardiac asthma has been defined as wheezing, coughing and orthopnea due to congestive heart failure. The clinical distinction between bronchial asthma and cardiac asthma can be straight forward, except in patients with chronic lung disease coexisting with left heart disease. Pulmonary edema and pulmonary vascular congestion have been thought to be the primary causes of cardiac asthma but most patients have a poor response to diuretics. There appears to be limited effectiveness of classical asthma medications like bronchodilators or corticosteroids in treating cardiac asthma. Evidence suggests that circulating inflammatory factors and tissue growth factors also lead to airway obstruction suggesting the possibility of developing novel therapies. PMID:23234454

Tanabe, Tsuyoshi; Rozycki, Henry J; Kanoh, Soichiro; Rubin, Bruce K

2012-12-01

275

Using the Nova target chamber for high-yield targets  

SciTech Connect

The existing 2.2-m-radius Nova aluminum target chamber, coated and lined with boron-seeded carbon shields, is proposed for use with 1000-MJ-yield targets in the next laser facility. The laser beam and diagnostic holes in the target chamber are left open and the desired 10/sup -2/ Torr vacuum is maintained both inside and outside the target chamber; a larger target chamber room is the vacuum barrier to the atmosphere. The hole area available is three times that necessary to maintain a maximum fluence below 12 J/cm/sup 2/ on optics placed at a radius of 10 m. Maximum stress in the target chamber wall is 73 MPa, which complies with the intent of the ASME Pressure Vessel Code. However, shock waves passing through the inner carbon shield could cause it to comminute. We propose tests and analyses to ensure that the inner carbon shield survives the environment. 13 refs.

Pitts, J.H.

1987-09-28

276

Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery in a Premature Infant with Preserved Left Ventricular Function  

Microsoft Academic Search

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare condition. The majority of cases\\u000a present with impaired left ventricular function. We report on a premature infant who was diagnosed at a gestational age near\\u000a term with ALCAPA during routine cardiac examination. The patient showed no signs of myocardial ischemia and is doing well\\u000a after

L. Grosse-Wortmann; T. Wenzl; H. H. Hoevels-Guerich

2006-01-01

277

Effect of anemia correction on left ventricular structure and filling pressure in anemic patients without overt heart disease  

PubMed Central

Background/Aims There are few data on the effects of low hemoglobin levels on the left ventricle (LV) in patients without heart disease. The objective of this study was to document changes in the echocardiographic variables of LV structure and function after the correction of anemia without significant cardiovascular disease. Methods In total, 34 iron-deficiency anemia patients (35 ± 11 years old, 32 females) without traditional cardiovascular risk factors or cardiovascular disease and 34 age- and gender-matched controls were studied. Assessments included history, physical examination, and echocardiography. Of the 34 patients with anemia enrolled, 20 were followed and underwent echocardiography after correction of the anemia. Results There were significant differences between the anemia and control groups in LV diameter, left ventricular mass index (LVMI), left atrial volume index (LAVI), peak mitral early diastolic (E) velocity, peak mitral late diastolic (A) velocity, E/A ratio, the ratio of mitral to mitral annular early diastolic velocity (E/E'), stroke volume, and cardiac index. Twenty patients underwent follow-up echocardiography after treatment of anemia. The follow-up results showed significant decreases in the LV end-diastolic and end-systolic diameters and LVMI, compared with baseline levels. LAVI, E velocity, and E/E' also decreased, suggesting a decrease in LV filling pressure. Conclusions Low hemoglobin level was associated with larger cardiac chambers, increased LV, mass and higher LV filling pressure even in the subjects without cardiovascular risk factors or overt cardiovascular disease. Appropriate correction of anemia decreased LV mass, LA volume, and E/E'. PMID:25045292

Cho, In-Jeong; Mun, Yeung Chul; Shin, Gil Ja

2014-01-01

278

Antipollution combustion chamber  

SciTech Connect

The invention concerns a combustion chamber for turbojet engines. The combustion chamber is of the annular type and consists of two coaxial flame tubes opening into a common dilution and mixing zone. The inner tube is designed for low operating ratings of the engine, the outer tube for high ratings. Air is injected as far upstream as possible into the dilution zone, to enhance the homogenization of the gaseous flow issuing from the two tubes prior to their passage into the turbine and to assure the optimum radial distribution of temperatures. The combustion chamber according to the invention finds application in a particularly advantageous manner in turbojet engines used in aircraft propulsion because of the reduced emission of pollutants it affords.

Caruel, J.E.; Gastebois, P.M.

1981-01-27

279

Emergency ligation of anomalous left coronary artery arising from the pulmonary artery  

Microsoft Academic Search

We report two cases of successful emergency ligation of anomalous left coronary artery arising from the pulmonary artery (ALCAPA) in patients with previous cardiac arrest. Both patients had regained marginal cardiac output after cardiopulmonary resuscitation and had maximal doses of inotropic support. The ALCAPA ligation was then performed as a life-saving procedure in the absence of any kind of mechanical

Christian Kreutzer; Andres J Schlichter; Maria Ines Roman; Guillermo O Kreutzer

2000-01-01

280

Filament wound rocket motor chambers  

NASA Technical Reports Server (NTRS)

The design, analysis, fabrication and testing of a Kevlar-49/HBRF-55A filament wound chamber is reported. The chamber was fabricated and successfully tested to 80% of the design burst pressure. Results of the data reduction and analysis from the hydrotest indicate that the chamber design and fabrication techniques used for the chamber were adequate and the chamber should perform adequately in a static test.

1976-01-01

281

Origins of Cardiac Fibroblasts  

PubMed Central

Cardiac fibroblasts play a critical role in maintenance of normal cardiac function. They are indispensable for damage control and tissue remodeling on myocardial injury and principal mediators of pathological cardiac remodeling and fibrosis. Despite their manyfold functions, cardiac fibroblasts remain poorly characterized in molecular terms. Evidence is evolving that cardiac fibroblasts are a heterogeneous population and likely derive from various distinct tissue niches in health and disease. Here, we review our emerging understanding of where cardiac fibroblasts come from, as well as how we can possibly use this knowledge to develop novel therapies for cardiac fibrosis. PMID:21106947

Zeisberg, Elisabeth M.; Kalluri, Raghu

2011-01-01

282

Uremia Aggravates Left Ventricular Remodeling after Myocardial Infarction  

Microsoft Academic Search

Background: Renal failure is a well-established cardiovascular risk factor. We hypothesized that uremia negatively affects post-myocardial infarction (MI) remodeling and left ventricular (LV) function and examined the pathohistological correlations. Methods: Subtotally nephrectomized rats (SNX) and controls with MI only (MIC) were examined 1, 4 and 8 weeks after MI. MI size, ejection fraction (EF), cardiac fibrosis, vascular density and cardiomyocyte

Ralf Dikow; Ulrike Schmidt; Lars P. Kihm; Matthias Schaier; Vedat Schwenger; Marie-Luise Gross; Hugo A. Katus; Martin Zeier; Stefan E. Hardt

2010-01-01

283

Thrombophilia, Left Ventricular Dysfunction and Intracardiac Thrombi in Children  

PubMed Central

Background and Objectives Reports on the incidence of intracardiac thrombi (ICT) have increased over the last few decades, but ICT are still relatively rare among children. Left ventricular systolic dysfunction and dilatation may contribute to the formation of ICT, especially when a hypercoagulable state exists. The aim of this study was to describe the incidence of ICT in children suffering from cardiac failure with left ventricular dysfunction and to identify risk factors on admission for developing ICT. Subjects and Methods We conducted a retrospective chart review of children up to 18 years of age admitted to the Pediatric Intensive Care Unit due to cardiac failure with left ventricular dysfunction between January 1, 2003 and December 31, 2008. Results Twenty-one patients were admitted with clinical signs of cardiac failure and echocardiographic findings compatible with dilated cardiomyopathy or acute myocarditis. Dilated cardiomyopathy was diagnosed in 11 patients (52%). Adenoviruses and enteroviruses were suspected to be the cause of acute myocarditis in 5 cases. The personal or family history of hypercoagulable states were obtained from 19 out of 21 patients (90%). Among patients with a hypercoagulable state, 3 out of 7 developed ICT compared with none out of 12 among patients without hypercoagulability (p=0.043). Two of these 3 patients experienced an embolic event. Conclusion Cardiac failure with left ventricular dysfunction may predispose the patient to ICT and increase the risk of thromboembolism, especially when an underlying hypercoagulable state exists. The hypercoagulable state must be carefully evaluated on admission in these patients. PMID:21949529

Baram, Shaul; Kozer, Eran; Klin, Baruch; Eshel, Gideon

2011-01-01

284

The renin-angiotensin system in left ventricular remodeling  

Microsoft Academic Search

Left ventricular remodeling is a dynamic process that occurs in reaction to an insult to the myocardium. The response to either loss of cells, as may occur following myocardial infarction, or to hemodynamic overload, as may occur in aortic stenosis, is an attempt to maintain cardiac output and normalize wall tension. This is accomplished through the activation of the renin-angiotensin

Ira S. Blaufarb; Edmund H. Sonnenblick

1996-01-01

285

Computational modeling and analysis for left ventricle motion using CT/Echo image fusion  

NASA Astrophysics Data System (ADS)

In order to diagnose heart disease such as myocardial infarction, 2D strain through the speckle tracking echocardiography (STE) or the tagged MRI is often used. However out-of-plane strain measurement using STE or tagged MRI is inaccurate. Therefore, strain for whole organ which are analyzed by simulation of 3D cardiac model can be applied in clinical diagnosis. To simulate cardiac contraction in a cycle, cardiac physical properties should be reflected in cardiac model. The myocardial wall in left ventricle is represented as a transversely orthotropic hyperelastic material, with the fiber orientation varying sequentially from the epicardial surface, through about 0° at the midwall, to the endocardial surface. A time-varying elastance model is simulated to contract myocardial fiber, and physiological intraventricular systolic pressure curves are employed for the cardiac dynamics simulation in a cycle. And an exact description of the cardiac motion should be acquired in order that essential boundary conditions for cardiac simulation are obtained effectively. Real time cardiac motion can be acquired by using echocardiography and exact cardiac geometrical 3D model can be reconstructed using 3D CT data. In this research, image fusion technology from CT and echocardiography is employed in order to consider patient-specific left ventricle movement. Finally, longitudinal strain from speckle tracking echocardiography which is known to fit actual left ventricle deformation relatively well is used to verify these results.

Kim, Ji-Yeon; Kang, Nahyup; Lee, Hyoung-Euk; Kim, James D. K.

2014-03-01

286

Calcific left atrium: A rare consequence of endocarditis  

PubMed Central

Usually, cardiac calcifications are observed in aortic and mitral valves, atrio-ventricular plane, mitral annulus, coronary arteries, pericaridium (usually causing constrictive pericarditis) and cardiac masses. Calcifications of atrial walls are unusual findings that can be identified only using imaging with high spatial resolution, such as cardiac magnetic resonance and computed tomography. We report a case of a 43-year-old patient with no history of heart disease that underwent cardiac evaluation for mild dyspnoea. The echocardiogram showed a calcific aortic valve and a hyper-echogenic lesion located in atrio-ventricular plane. The patient was submitted to cardiac magnetic resonance and to computed tomography imaging to better characterize the localization of mass. The clinical features and location of calcified lesion suggest an infective aetiology causing an endocarditis involving the aortic valve, atrio-ventricular plane and left atrium. Although we haven’t data to support a definite and clear diagnosis, the clinical features and location of the calcified lesion suggest an infective aetiology causing an endocarditis involving the aortic valve, atrio-ventricular plane and left atrium. The patient was followed for 12 mo both clinically and by electrocardiogram and echocardiography without worsening of clinical, electrocardiographic and echocardiographic data. Cardiac magnetic resonance imaging and computed tomography are ideal methods for identifying and following over time patients with calcific degeneration in the heart.

Dattilo, Giuseppe; Anfuso, Carmelo; Casale, Matteo; Giugno, Vincenza; Camarda, Lorenzo; Lagana, Natascia; Di Bella, Gianluca

2014-01-01

287

Transthoracic echocardiographic predictors of left atrial hypertension in patients on venoarterial extracorporeal membrane oxygenation.  

PubMed

Decompression of the left heart in patients supported with extracorporeal membrane oxygenation (ECMO) is often warranted to protect the myocardium and facilitate recovery. We studied the ability of standard echocardiographic parameters to predict left atrial hypertension by reviewing 3 cardiac patients supported with ECMO who subsequently underwent left atrial decompression. We found that standard echocardiographic parameters poorly predict the need for left atrial decompression on ECMO. Following a more specific diagnostic algorithm to estimate left-sided filling pressure in patients with depressed ejection fraction may significantly improve the ability of echocardiography to accurately predict left atrial hypertension and the need for decompression. PMID:24403357

Eckhauser, Aaron W; Jones, Chris; Witte, Madolin K; Puchalski, Michael D

2014-01-01

288

Echocardiographic assessment of cardiac disease  

NASA Technical Reports Server (NTRS)

The physical principles and current applications of echocardiography in assessment of heart diseases are reviewed. Technical considerations and unresolved points relative to the use of echocardiography in various disease states are stressed. The discussion covers normal mitral valve motion, mitral stenosis, aortic regurgitation, atrial masses, mitral valve prolapse, and idiopathic hypertrophic subaortic stenosis. Other topics concern tricuspic valve abnormalities, aortic valve disease, pulmonic valve, pericardial effusion, intraventricular septal motion, and left ventricular function. The application of echocardiography to congenital heart disease diagnosis is discussed along with promising ultrasonic imaging systems. The utility of echocardiography in quantitative evaluation of cardiac disease is demonstrated.

Popp, R. L.

1976-01-01

289

Hypoplastic left heart syndrome in PAGOD syndrome.  

PubMed

Chromosomal abnormalities as well as non-cardiac anomalies have been identified as independent risk factors for surgical morbidity and mortality in Fontan palliation. The combination of malformations consisting of pulmonary hypoplasia, agonadism (sex reversal), omphalocele, and diaphragmatic defect is compatible with pulmonary artery and lung hypoplasia, agonadism, omphalocele, and diaphragmatic defect (PAGOD). Most cases have been associated with cardiac disease, particularly hypoplastic left heart syndrome (HLHS) that is potentially destined for Fontan palliation. Reported herein is the case of a Japanese female infant diagnosed with PAGOD syndrome along with HLHS (mitral atresia and aortic atresia), in whom intractable respiratory failure manifested as bilateral eventration of the diaphragm and presumed right lung hypoplasia. These characteristic pulmonary lesions associated with the syndrome precluded use of the Fontan pathway. PMID:24894929

Takahashi, Kazuhiro; Miyake, Akira; Nakayashiro, Mami

2014-06-01

290

Bubble Chamber Site  

NSDL National Science Digital Library

This substantial site features a large number of photos of bubble chamber (BC) tracks, many with a discussion of the physics. There is a description of how the BC works and also useful tutorial on reading BC pictures. The high quality of the images and the explanations of the events that are shown make this site especially valuable.

2006-06-19

291

Phototherapy irradiation chamber  

Microsoft Academic Search

A phototherapy irradiation chamber having substantial uniformity of irradiance therewithin comprises an array of vertical fluorescent lamps surrounding the irradiation space. Reflectors are located within the array at the top and bottom thereof. The ends of the lamps extend beyond the reflectors. 8 claims.

1978-01-01

292

The KLOE drift chamber  

Microsoft Academic Search

The stringent requirements of the KLOE experiment on dimensions, efficiency, resolution and transparency of its drift chamber led to building a tracking device which can be considered innovative from many points of view.Details of the design and construction of this detector, together with preliminary results from the test of its full scale prototype, constructed and operated under a test beam

A. Andryakov; A. Antonelli; R. Baldini-Ferroli; G. Bencivenni; L. Bucci; A. Calcaterra; P. L Campana; S Dell'Agnello; R De Sangro; P De Simone; G. Felici; C. Forti; G. Finocchiaro; V. Kulikov; S. Moccia; A. Nedosekin; V. Patera; M. Piccolo; A. Denig; M. Imhof; W. Kluge; U Von Hagel; S. Weseler; G. Cataldi; P. Creti; V. Elia; V. Golovatyuk; E. Gorini; F. Grancagnolo; M. Panareo; M. Primavera; S. Spagnolo; C. Bacci; F. Ceradini; E De Lucia; F La Cava; C. Luisi; G. Margutti; D. Picca; L. Pontecorvo; R. Messi; L. Paoluzi; E. Pasqualucci; P. Valente

1996-01-01

293

Improved wire chamber  

DOEpatents

An improved gas mixture for use with proportional counter devices, such as Geiger-Mueller tubes and drift chambers. The improved gas mixture provides a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor. 2 figs.

Atac, M.

1987-05-12

294

Liquid Wall Chambers  

SciTech Connect

The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

Meier, W R

2011-02-24

295

Quantitative coronary and left ventricular cineangiography  

SciTech Connect

The first section, with 12 chapters, deals with the detailed methods of computer analysis of images obtained from coronary vessels and the left ventricle. Basic principles of x-ray image formation are described, followed by details of the computer-based Cardiovascular Angiography Analysis system (CAAs) and the left-ventricular angioprocessing system (Contouromat), with their degree of validity. Other chapters discuss contour analysis, edge detection, densitometry, digital image processing, three-dimensional reconstruction, and the current status of structural analysis of the entire coronary tree. The second edition section contains 11 chapters, each exemplifying the application of these computer-based systems to almost the entire sphere of interventional cardiac imaging. Applications include intracoronary effects of nifedipine on coronary motility, left-ventricular function and myocardial oxygen consumption, various aspects of percutaneous transluminal coronary angioplasty (including left-ventricular wall stiffness), adjuvant thrombolysis, comparison of contour versus densitometric area measurements of coronary obstructions before and after percutaneous transluminal coronary angioplasty, and left-ventricular performance including lactate metabolism during vessel occlusion.

Reiber, J.H.C.; Serruys, P.W.; Slager, C.J.

1986-01-01

296

Transseptal fine needle aspiration of a large left atrial tumour.  

PubMed

The diagnosis of cardiac tumours is often based on images without tissue diagnosis or tissue obtained at surgery. Percutaneous myocardial biopsy via a transvenous approach has been described in literatures but this technique is not feasible with left atrial tumours. We report a patient presenting with heart failure and left atrial tumour. The diagnosis of spindle cell neoplasm was established pre-operatively via successful transseptal fine needle aspiration of cells from a left atrial tumour. We believe this technique worth consideration to aid pre-surgery diagnosis. PMID:19656723

Wong, Chi Wing; Ruygrok, Peter; Sutton, Timothy; Ding, Patricia; van Vliet, Chris; Occleshaw, Christopher; Smith, Warren

2010-07-01

297

Left Ventricular Functional Analysis Using 64Slice Multidetector Row Computed Tomography: Comparison with Left Ventriculography and Cardiovascular Magnetic Resonance  

Microsoft Academic Search

Objective: The progress in computed tomography (CT) has improved temporal resolution and shortened the acquisition time. We compared cardiac function using 64-slice CT with left ventriculography (LVG) and cardiovascular magnetic resonance (CMR). Methods: A head-to-head comparison between CT, LVG and CMR was performed in 41 patients. In global LV function, CMR served as the reference. Regional wall motion was compared

Yen-Wen Wu; Eiji Tadamura; Shotaro Kanao; Masaki Yamamuro; Satoshi Okayama; Neiko Ozasa; Masanao Toma; Takeshi Kimura; Toru Kita; Akira Marui; Masashi Komeda; Kaori Togashi

2008-01-01

298

[Cardiac changes in mediastinal seminoma].  

PubMed

Primary pure cell seminoma of the mediastinum is a rare and potentially fatal lesion. Encroachment or invasion of adjacent structures is common, as are distant metastases. We present an unusual case of mediastinal seminoma with directly intracavitary invasion into the right atrium and extension to the left atrium. A 22-year-old male with right side chest pain, progressive cough, dyspnea, fever and right arm swelling lasting about a month is presented. Chest radiography on admission revealed a large mass in the anterior mediastinum. A cardiac ultrasonographic examination showed right atrial compression by the mass, with invasion of the right atrium wall. We also found polyp-like (about 2.5 cm in diameter) masses in left atrium near the area of the right pulmonary veins and a circumferential pericardial effusion. Percutaneous needle biopsy revealed mediastinal seminoma. To our knowledge, no similar case has been previously reported. PMID:15058221

Ivanovi?, Branislava; Vujisi?-Tesi?, Bosiljka; Jovanovi?, Dragana; Kalinovska-Ostri?, Dimitra

2003-01-01

299

Electrical stimulation systems for cardiac tissue engineering.  

PubMed

We describe a protocol for tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cells with the application of pulsatile electrical fields designed to mimic those present in the native heart. Tissue culture is conducted in a customized chamber built to allow for cultivation of (i) engineered three-dimensional (3D) cardiac tissue constructs, (ii) cell monolayers on flat substrates or (iii) cells on patterned substrates. This also allows for analysis of the individual and interactive effects of pulsatile electrical field stimulation and substrate topography on cell differentiation and assembly. The protocol is designed to allow for delivery of predictable electrical field stimuli to cells, monitoring environmental parameters, and assessment of cell and tissue responses. The duration of the protocol is 5 d for two-dimensional cultures and 10 d for 3D cultures. PMID:19180087

Tandon, Nina; Cannizzaro, Christopher; Chao, Pen-Hsiu Grace; Maidhof, Robert; Marsano, Anna; Au, Hoi Ting Heidi; Radisic, Milica; Vunjak-Novakovic, Gordana

2009-01-01

300

Electrical stimulation systems for cardiac tissue engineering  

PubMed Central

We describe a protocol for tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cells with the application of pulsatile electrical fields designed to mimic those present in the native heart. Tissue culture is conducted in a customized chamber built to allow for cultivation of (i) engineered three-dimensional (3D) cardiac tissue constructs, (ii) cell monolayers on flat substrates or (iii) cells on patterned substrates. This also allows for analysis of the individual and interactive effects of pulsatile electrical field stimulation and substrate topography on cell differentiation and assembly. The protocol is designed to allow for delivery of predictable electrical field stimuli to cells, monitoring environmental parameters, and assessment of cell and tissue responses. The duration of the protocol is 5 d for two-dimensional cultures and 10 d for 3D cultures. PMID:19180087

Tandon, Nina; Cannizzaro, Christopher; Chao, Pen-Hsiu Grace; Maidhof, Robert; Marsano, Anna; Au, Hoi Ting Heidi; Radisic, Milica; Vunjak-Novakovic, Gordana

2009-01-01

301

Left ventricular basal region involvement in noncompaction cardiomyopathy.  

PubMed

A previously healthy 16-year-old woman experienced progressive dyspnea on exertion. The echocardiogram and cardiac magnetic resonance imaging showed a significant increase in cardiac chambers, severe biventricular systolic dysfunction, and prominent ventricular trabeculations suggesting noncompaction cardiomyopathy (NCC). The patient underwent heart transplantation 5 years after the NCC diagnosis, and the anatomopathological examination evidenced diffuse biventricular hypertrabeculation compromise, including the basal region of the biventricular wall. There is no consensus about the gold-standard diagnostic criteria, which demands a conceptual review and attention to another point: the relation of trabeculation volume and prognosis. PMID:23797018

de Melo, Marcelo Dantas Tavares; Benvenuti, Luiz A; Mady, Charles; Kalil-Filho, Roberto; Salemi, Vera M C

2013-01-01

302

Left Business Observer  

NSDL National Science Digital Library

Edited by Wall Street author Doug Henwood, the Left Business Observer site features selected articles from the print journal by the same name (1992-present). The site provides special reports on current political issues, in addition to a discussion forum and US labor statistics with commentary from a "left" perspective.

303

CARDIAC MUSCLE  

PubMed Central

With light and electron microscopy a comparison has been made of the morphology of ventricular (V) and Purkinje (P) fibers of the hearts of guinea pig, rabbit, cat, dog, goat, and sheep. The criteria, previously established for the rabbit heart, that V fibers are distinguished from P fibers by the respective presence and absence of transverse tubules is shown to be true for all animals studied. No evidence was found of a permanent connection between the sarcoplasmic reticulum and the extracellular space. The sarcoplasmic reticulum (SR) of V fibers formed couplings with the sarcolemma of a transverse tubule (interior coupling) and with the peripheral sarcolemma (peripheral coupling), whereas in P fibers the SR formed only peripheral couplings. The forms of the couplings were identical. The significance, with respect to excitation-contraction coupling, of the difference in the form of the couplings in cardiac versus skeletal muscle is discussed together with the electrophysiological implications of the differing geometries of bundles of P fibers from different animals. PMID:5645545

Sommer, Joachim R.; Johnson, Edward A.

1968-01-01

304

Multi-chamber deposition system  

DOEpatents

A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

1989-10-17

305

Multi-chamber deposition system  

DOEpatents

A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

1989-06-27

306

Combustor with fuel preparation chambers  

NASA Technical Reports Server (NTRS)

An annular combustor having fuel preparation chambers mounted in the dome of the combustor. The fuel preparation chamber comprises an annular wall extending axially from an inlet to an exit that defines a mixing chamber. Mounted to the inlet are an air swirler and a fuel atomizer. The air swirler provides swirled air to the mixing chamber while the atomizer provides a fuel spray. On the downstream side of the exit, the fuel preparation chamber has an inwardly extending conical wall that compresses the swirling mixture of fuel and air exiting the mixing chamber.

Zelina, Joseph (Inventor); Myers, Geoffrey D. (Inventor); Srinivasan, Ram (Inventor); Reynolds, Robert S. (Inventor)

2001-01-01

307

Limitations of Current Echocardiographic Nomograms for Left ventricular, Valvular and Arterial Dimensions in Children: a Critical Review  

Microsoft Academic Search

An echocardiographic quantitative evaluation of the cardiac and vascular structures is often of critical importance for diagnosis and management of congenital heart diseases. We reviewed the accuracy and limits of published echocardiographic nomograms for cardiac chambers, valve and main vessel dimensions in children, with special attention to the neonatal age.A computerized literature search in the National Library of Medicine using

Massimiliano Cantinotti; Marco Scalese; Molinaro Sabrina; Bruno Murzi; Claudio Passino

308

Left ventricular pseudoaneurysm: A case report and review of the literature  

PubMed Central

Left ventricular (LV) pseudoaneurysm is a rare complication that is reported in less than 0.1% of all patients with myocardial infarction. It is the result of cardiac rupture contained by the pericardium and is characterized by the absence of myocardial tissue in its wall unlike true aneurysm which involves full thickness of the cardiac wall. The clinical presentation of these patients is nonspecific, making the diagnosis challenging. Transthoracic echocardiogram and cardiac magnetic resonance imaging are the noninvasive modalities whereas coronary arteriography and left ventriculography are invasive modalities used for the diagnosis. As this condition is lethal, prompt diagnosis and timely management is vital. PMID:24749118

Alapati, Lavanya; Chitwood, W Randolph; Cahill, John; Mehra, Sanjay; Movahed, Assad

2014-01-01

309

Multiwire proportional chamber development  

NASA Technical Reports Server (NTRS)

The development of large area multiwire proportional chambers, to be used as high resolution spatial detectors in cosmic ray experiments is described. A readout system was developed which uses a directly coupled, lumped element delay-line whose characteristics are independent of the MWPC design. A complete analysis of the delay-line and the readout electronic system shows that a spatial resolution of about 0.1 mm can be reached with the MWPC operating in the strictly proportional region. This was confirmed by measurements with a small MWPC and Fe-55 X-rays. A simplified analysis was carried out to estimate the theoretical limit of spatial resolution due to delta-rays, spread of the discharge along the anode wire, and inclined trajectories. To calculate the gas gain of MWPC's of different geometrical configurations a method was developed which is based on the knowledge of the first Townsend coefficient of the chamber gas.

Doolittle, R. F.; Pollvogt, U.; Eskovitz, A. J.

1973-01-01

310

Scimitar syndrome with absence of the right pulmonary artery: A case with volume-induced, reversible, left-sided pulmonary hypertension  

Microsoft Academic Search

An infant with scimitar syndrome, absent right pulmonary artery, and systemic blood supply to the right lung presented in severe cardiac failure. Cardiac catheterization revealed suprasystemic pressure of the left pulmonary artery and a high pulmonary vascular resistance. Right-sided pneumonectomy abolished cardiac failure and normalized both pulmonary artery pressure and resistance. Pure volume load affecting one lung—as in this case

Albrecht Beitzke; Gerfried Zobel; Bruno Rigler; Jörg Ingolf Stein; Christa Suppan

1992-01-01

311

In vivo monitoring of acetylcholine release from cardiac vagal nerve endings in anesthetized mice.  

PubMed

We applied a microdialysis technique to the left ventricular myocardium of anesthetized mice and tried to monitor acetylcholine (ACh) release from cardiac vagal nerves. Transection of bilateral cervical vagal nerves decreased dialysate ACh concentration. Electrical stimulation of the left cervical vagal nerve increased dialysate ACh concentration in proportion to the frequency of stimulation. Intravenous administration of hexamethonium, prevented the increase in dialysate ACh concentration during vagal nerve stimulation, indicating that ACh in the dialysate primarily reflects ACh released from post-ganglionic cardiac vagal nerves. Microdialysis permits monitoring of ACh release from post-ganglionic cardiac vagal nerves that are most likely to be innervating the left ventricle in mice. PMID:23499513

Zhan, Dong-Yun; Du, Cheng-Kun; Akiyama, Tsuyoshi; Sonobe, Takashi; Tsuchimochi, Hirotsugu; Shimizu, Shuji; Kawada, Toru; Shirai, Mikiyasu

2013-06-01

312

Left renal atrophy  

PubMed Central

Background: We tried to understand whether or not there is a higher risk of left renal atrophy in human being. Methods: All patients applying to the Hematology Service with any underlying complaint were studied. Results: The study included 2,417 cases (1,248 females). The mean ages were 47.3 versus 50.7 years in females and males, respectively (p<0.000). There were 33 cases (1.3%) with the left renal atrophy against five cases (0.2%) with the right (p<0.001). The left renal atrophy cases have splenomegaly (SM) in 51.5%, thalassemia minors (TMs) in 30.3%, sickle cell diseases (SCDs) in 27.2%, myeloproliferative disorders in 18.1%, chronic lymphocytic leukemia in 6.0%, cirrhosis in 6.0%, solid organ malignancies in 6.0%, chronic obstructive pulmonary disease in 3.0%, multiple myeloma in 3.0%, and Waldenström’s macroglobulinemia in 3.0%. Similarly, the right renal atrophy cases have SM in 20.0%, TMs in 40.0%, and SCDs in 20.0%. Conclusion: Left renal atrophy may be significantly higher than the right side in human being. Aortic pressure induced flow disorders in the left renal vein, structural anomalies of the left renal vein, and possibly the higher arterial pressure of the left kidney due to the shorter distance to the heart as an underlying cause of atherosclerosis may be some of the possible causes. Due to the stronger arterial wall protecting itself from compression and high prevalences of SM and left varicocele in population, SM induced flow disorders of the left renal vein may be the most common cause. PMID:25035786

Davran, Ramazan; Helvaci, Mehmet Rami; Davarci, Mursel

2014-01-01

313

Cardiac arrest during percutaneous coronary intervention in a patient 'resistant' to clopidogrel - successful 50-minute mechanical chest compression  

PubMed Central

We report a case of 72-year-old female patient with end-stage chronic kidney disease, undergoing percutaneous coronary intervention (PCI) that resulted in a cardiac arrest caused by a thrombus mediated flow limitation in the left coronary artery. With mechanical cardiopulmonary resuscitation (CPR) PCI of the left main artery was performed successfully during 50 min cardiac arrest. The patient was discharged from the hospital without compromising cardiac function and neurological deficits. PMID:24570760

Szymkiewicz, Pawel; Sciborski, Krzysztof; Orda, Alina; Karolko, Bozena; Jonkisz, Anna; Lebioda, Arleta; Mysiak, Andrzej

2013-01-01

314

Successful extracorporeal circulatory support after aortic reimplantation of anomalous left coronary artery  

Microsoft Academic Search

The development of severe heart failure is the main cause of postoperative mortality after the surgical treatment of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). Two patients with ALCAPA who developed low cardiac output and could not be weaned from cardiopulmonary bypass (CPB) after aortic reimplantation of the the anomalous left coronary artery were successfully

V. Alexi-Meskishvili; R. Hetzer; Y. Weng; M. Loebe; P. E. Lange; K. Ishino

1994-01-01

315

Anomalous left coronary artery from the pulmonary artery: Case report and review of the literature  

Microsoft Academic Search

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is an uncommon occurrence, usually diagnosed at a young age. We report a 71-year-old patient who died suddenly of acute bilateral bronchopneumonia, and was found to have ALCAPA at autopsy. The patient had reported no cardiac symptoms during his lifetime. Autopsy revealed collateral connections between the left coronary

Shaun W. Leong; Aidan J. Borges; Jessica Henry; Jagdish Butany

2009-01-01

316

TWO-CORONARY REPAIR FOR ANOMALOUS LEFT CORONARY ARTERY FROM PULMONARY ARTERY  

Microsoft Academic Search

Between January 1989 and December 1998, 13 patients (7 males) aged 3 months to 32 years, underwent surgery for anomalous left coronary artery from the pulmonary artery. Eight presented with congestive cardiac failure and all had evidence of left ventricular dysfunction. One patient had associated tetralogy of Fallot. Preoperative diagnosis was established by echocardiography and cineangiography. Nine patients underwent Takeuchi

Sachin Talwar; Anil Bhan; Rajesh Sharma; Shiv Kumar Choudhary; Balram Airan; Anita Saxena; Shyam Sunder Kothari; Rajnish Juneja

317

Left Ventricular Systolic Unloading and Augmentation of Intracoronary Pressure and Doppler Flow During Enhanced External Counterpulsation  

Microsoft Academic Search

Background—Enhanced external counterpulsation (EECP) is a noninvasive, pneumatic technique that provides beneficial effects for patients with chronic, symptomatic angina pectoris. However, the physiological effects of EECP have not been studied directly. We examined intracoronary and left ventricular hemodynamics in the cardiac catheterization laboratory during EECP. Methods and Results—Ten patients referred for diagnostic evaluation underwent left heart catheterization and coronary angiography

Andrew D. Michaels; Michel Accad; Thomas A. Ports; William Grossman

318

Echocardiographic left ventricular systolic function and volumes in young adults: Distribution and factors influencing variability  

Microsoft Academic Search

Low left ventricular ejection fraction (LVEF), a measure of global systolic left ventricular dysfunction, is associated with an increased risk of recurrent coronary events or death in persons with cardiac disease. There are few data on the distribution of resting LVEF and component volumes in healthy young adults or on any associaton of LVEF with coronary risk factors. LVEF and

Nathan D. Wong; Julius M. Gardin; Tom Kurosaki; Hoda Anton-Culver; Stephen Sidney; Jeffrey Roseman; Samuel Gidding

1995-01-01

319

Impact of Acute Changes of Left Ventricular Contractility on the Transvalvular Impedance: Validation Study by Pressure-Volume Loop Analysis in Healthy Pigs  

PubMed Central

Background The real-time and continuous assessment of left ventricular (LV) myocardial contractility through an implanted device is a clinically relevant goal. Transvalvular impedance (TVI) is an impedentiometric signal detected in the right cardiac chambers that changes during stroke volume fluctuations in patients. However, the relationship between TVI signals and LV contractility has not been proven. We investigated whether TVI signals predict changes of LV inotropic state during clinically relevant loading and inotropic conditions in swine normal heart. Methods The assessment of RVTVI signals was performed in anesthetized adult healthy anesthetized pigs (n?=?6) instrumented for measurement of aortic and LV pressure, dP/dtmax and LV volumes. Myocardial contractility was assessed with the slope (Ees) of the LV end systolic pressure-volume relationship. Effective arterial elastance (Ea) and stroke work (SW) were determined from the LV pressure-volume loops. Pigs were studied at rest (baseline), after transient mechanical preload reduction and afterload increase, after 10-min of low dose dobutamine infusion (LDDS, 10 ug/kg/min, i.v), and esmolol administration (ESMO, bolus of 500 µg and continuous infusion of 100 µg·kg?1·min?1). Results We detected a significant relationship between ESTVI and dP/dtmax during LDDS and ESMO administration. In addition, the fluctuations of ESTVI were significantly related to changes of the Ees during afterload increase, LDDS and ESMO infusion. Conclusions ESTVI signal detected in right cardiac chamber is significantly affected by acute changes in cardiac mechanical activity and is able to predict acute changes of LV inotropic state in normal heart. PMID:24260431

Lionetti, Vincenzo; Romano, Simone Lorenzo; Bianchi, Giacomo; Bernini, Fabio; Dushpanova, Anar; Mascia, Giuseppe; Nesti, Martina; Di Gregorio, Franco; Barbetta, Alberto; Padeletti, Luigi

2013-01-01

320

Right or Left?  

NSDL National Science Digital Library

This activity challenges students to visualize compound transformations of hexahedral dice to determine their right- or left-handedness. Ideas for implementation and support are included along with printable sheets of both types of dice.

2004-06-01

321

Left heart catheterization  

MedlinePLUS

Catheterization - left heart ... to carefully guide the catheters up into your heart and arteries. Dye will be injected into your ... in the blood vessels that lead to your heart. The catheter is the moved through the aortic ...

322

Cardiac Syndrome X  

MedlinePLUS

Related terms: angina, microvascular angina Cardiac syndrome X patients have the pain of angina , but they do not have coronary artery disease ( CAD ). So even though patients with cardiac syndrome X ...

323

Cardiac imaging and functional assessment in pregnancy.  

PubMed

There are multiple imaging modalities available for the assessment of pregnant women with known or suspected cardiac disease. Because of its safety and general availability, echocardiography is the preferred study of choice for the evaluation of ventricular function, valvular heart disease, congenital heart disease, evaluation of the aorta, and the estimation of cardiac hemodynamics in a pregnant patient. Cardiac MRI can be performed, especially for diseases of the aorta and complex congenital heart disease. Radiation exposure for the fetus and the mother will be discussed in the use of CT angiography, nuclear imaging, and left-heart catheterization including coronary angiography for specific indications in the pregnant woman. The use of exercise testing during pregnancy for functional assessment will be presented. PMID:25037513

Waksmonski, Carol A

2014-08-01

324

Determinants of Right Ventricular Muscle Mass in Idiopathic Dilated Cardiomyopathy: Impact of Left Ventricular Muscle Mass and Pulmonary Hypertension  

PubMed Central

Introduction: Although chronic pulmonary hypertension and right ventricular (RV) function carry important functional and prognostic implications in idiopathic dilated cardiomyopathy (IDC), little information on RV muscle mass (RVMM) and its determinants has been published. Methods: Our study comprised thirty-five consecutive patients with IDC, left ventricular (LV) ejection fraction <40% and NYHA class ?2. Hemodynamic data and parameters on LV and RV geometry were derived from right heart catheterisation and cardiac magnetic resonance imaging. Results: RVMM was normalized to body size using a common linear, body surface area based approach (RVMMI) and by an allometric index (RVMM-AI) incorporating adjustment for age, height and weight. Stepwise multiple regression analysis revealed that pulmonary artery pressure and left ventricular muscle mass were independent predictors of RVMM-AI. The interventricular mass ratio of RV and LV mass (IVRM) was closely related to RVMM (r = 0.79, p < 0.001) and total muscle mass (r = 0.39, p < 0.02). However, there was no significant relationship between LVMM and IVMR (r = 0.17, p = 0.32). Conclusion: Our data suggest that an increase in RV mass in IDC may be explained by two mechanisms: First, as a consequence of the myopathic process itself resulting in a balanced hypertrophy of both ventricles. Second, due to the chamber specific burden of pulmonary artery pressure rise, resulting in unbalanced RV hypertrophy. PMID:24936147

Vormbrock, Julia; Liebeton, Jeanette; Wirdeier, Sophia; Meissner, Axel; Butz, Thomas; Trappe, Hans-Joachim; Plehn, Gunnar

2014-01-01

325

Ionization chamber dosimeter  

DOEpatents

A method for fabricating an ion chamber dosimeter collecting array of the type utilizing plural discrete elements formed on a uniform collecting surface which includes forming a thin insulating layer over an aperture in a frame having surfaces, forming a predetermined pattern of through holes in the layer, plating both surfaces of the layer and simultaneously tilting and rotating the frame for uniform plate-through of the holes between surfaces. Aligned masking and patterned etching of the surfaces provides interconnects between the through holes and copper leads provided to external circuitry.

Renner, Tim R. (Berkeley, CA); Nyman, Mark A. (Berkeley, CA); Stradtner, Ronald (Kensington, CA)

1991-01-01

326

Cardiogenetics, Neurogenetics, and Pathogenetics of Left Ventricular Hypertrabeculation\\/Noncompaction  

Microsoft Academic Search

Background  Left ventricular hypertrabeculation (LVHT), also known as noncompaction or spongy myocardium, is a cardiac abnormality of\\u000a unknown etiology and pathogenesis frequently associated with genetic cardiac and noncardiac disorders, particularly genetic\\u000a neuromuscular disease. This study aimed to review the current knowledge about the genetic or pathogenetic background of LVHT.\\u000a \\u000a \\u000a \\u000a Methods  A literature review of all human studies dealing with the association of

Josef Finsterer

2009-01-01

327

Doppler echocardiographic parameters of evaluation of left ventricular systolic function.  

PubMed

The authors suggest a new method using Doppler echocardiography for the evaluation of cardiac performance. Doppler echocardiography permits the calculation of left ventricular (LV) ejection force (according to Newton's second law of motion). The ejection force was calculated in 36 patients with heart failure subgrouped into 3 groups based on ejection fraction (EF) (> 60%; 41-60%; < 40%) compared to 11 normal subjects. The LV ejection force showed a good linear correlation with LV ejection fraction (r = 0.86). Data of the study suggest that the LV ejection force is a valuable and accurate index for the assessment of cardiac performance, especially in early stages of disease. PMID:8130754

Dr?gulescu, S I; Ro?u, D; Abazid, J; Ionac, A

1993-01-01

328

Carotid-cardiac baroreflex response and LBNP tolerance following resistance training  

NASA Technical Reports Server (NTRS)

The purpose of this study was to examine the effect of lower body resistance training on cardiovascular control mechanisms and blood pressure maintenance during an orthostatic challenge. Lower body negative pressure (LBNP) tolerance, carotid-cardiac baroreflex function (using neck chamber pressure), and calf compliance were measured in eight healthy males before and after 19 wk of knee extension and leg press training. Resistance training sessions consisted of four or five sets of 6-12 repetitions of each exercise, performed two times per week. Training increased strength 25 +/- 3 (SE) percent (P = 0.0003) and 31 +/- 6 percent (P = 0.0004), respectively, for the leg press and knee extension exercises. Average fiber size in biopsy samples of m. vastus lateralis increased 21 +/- 5 percent (P = 0.0014). Resistance training had no significant effect on LBNP tolerance. However, calf compliance decreased in five of the seven subjects measured, with the group average changing from 4.4 +/- 0.6 ml.mm Hg-1 to 3.9 +/- 0.3 ml.mm Hg-1 (P = 0.3826). The stimulus-response relationship of the carotid-cardiac baroreflex response shifted to the left on the carotid pressure axis as indicated by a reduction of 6 mm Hg in baseline systolic blood pressure (P = 0.0471). In addition, maximum slope increased from 5.4 +/- 1.3 ms.mm Hg-1 before training to 6.6 +/- 1.6 ms.mm Hg-1 after training (P = 0.0141). Our results suggest the possibility that high resistance, lower extremity exercise training can cause a chronic increase in sensitivity and resetting of the carotid-cardiac baroreflex.

Tatro, D. L.; Dudley, G. A.; Convertino, V. A.

1992-01-01

329

Anomalous origin of the left coronary artery: the effects of aortocoronary vein bypass on left ventricular function  

PubMed Central

The diagnosis, angiographic evaluation and surgical treatment by aortocoronary vein bypass are described in a 3½-year-old girl with anomalous origin of the left coronary artery from the pulmonary artery. The anomaly had resulted in cardiac dilatation, diminished left ventricular contractility, an aneurysm of the left ventricular free wall and mitral regurgitation. At the postoperative cardiac catheterization the graft was demonstrated to be patent, but a significant proportion of the flow to the left coronary artery was derived from anastomotic connections with the right coronary artery. The most striking evidence of improvement was obtained from the left ventricular volume studies which showed that the end systoiic volume had decreased from 85 to 49 ml./m.2 with an increase in ejection fraction from 0.39 to 0.62, suggesting enhanced left ventricular contractility after surgery. The patient continues to do well and is free from symptoms. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5FIG. 6FIG. 7FIG. 8 PMID:5041933

Tyrrell, Michael J.; Bharadwaj, Baikunth

1972-01-01

330

[Cardiac failure in a child during anesthetic induction with sevoflurane].  

PubMed

A five-year-old boy with recurring tonsillitis and sleep apnea was admitted for tonsillectomy and tympanic membrane tubing. He presented with a history of bronchial asthma and hereditary spherocytosis without obvious cardiac failure symptoms. Anesthetic agents for induction included nitrous oxide, oxygen, and sevoflurane. Because oxygen saturation decreased immediately to 90%, tracheal intubation was performed. The patient began to wheeze. Sevoflurane concentration was increased but cardiac murmur (gallop), cold limbs and jugular vein distension were noted. Acute cardiac failure was diagnosed following a chest X-ray and cardiac echo showing an enlarged heart, CTR of 80%, left ventricular dilation, and contractile failure. Tympanic membrane tubing only was performed. Sevoflurane was discontinued and the patient was treated for the cardiac failure under an ICU oxygen tent. The patient was discharged when his general condition improved. He showed elevated levels of viral antibodies, suggesting myocarditis. Later he was treated for dilating cardiomyopathy before undergoing a heart transplant. PMID:16984022

Oto, Hirotaka; Nakamura, Tadaho; Nakamura, Kyouichi; Tani, Makiko; Kobayashi, Osamu; Takahashi, Yukio

2006-09-01

331

Ventricular hemodynamics using cardiac computed tomography and optical flow method.  

PubMed

Ventricular hemodynamics plays an important role in assessing cardiac function in clinical practice. The aim of this study was to determine the ventricular hemodynamics based on contrast movement in the left ventricle (LV) between the phases in a cardiac cycle recorded using an electrocardiography (ECG) with cardiac computed tomography (CT) and optical flow method. Cardiac CT data were acquired at 120 kV and 280 mA with a 350 ms gantry rotation, which covered one cardiac cycle, on the 640-slice CT scanner with ECG for a selected patient without heart disease. Ventricular hemodynamics (mm/phase) were calculated using the optical flow method based on contrast changes with ECG phases in anterior-posterior, lateral and superior-inferior directions. Local hemodynamic information of the LV with color coating was presented. The visualization of the functional information made the hemodynamic observation easy. PMID:24463391

Lin, Yang-Hsien; Huang, Yung-Hui; Lin, Kang-Ping; Liu, Juhn-Cherng; Huang, Tzung-Chi

2014-01-01

332

Artificial Left Ventricle  

E-print Network

This Artificial left ventricle is based on a simple conic assumption shape for left ventricle where its motion is made by attached compressed elastic tubes to its walls which are regarded to electrical points at each nodal .This compressed tubes are playing the role of myofibers in the myocardium of the left ventricle. These elastic tubes have helical shapes and are transacting on these helical bands dynamically. At this invention we give an algorithm of this artificial left ventricle construction that of course the effect of the blood flow in LV is observed with making beneficiary used of sensors to obtain this effecting, something like to lifegates problem. The main problem is to evaluate powers that are interacted between elastic body (left ventricle) and fluid (blood). The main goal of this invention is to show that artificial heart is not just a pump, but mechanical modeling of LV wall and its interaction with blood in it (blood movement modeling) can introduce an artificial heart closed to natural heart...

Ranjbar, Saeed; Meybodi, Mahmood Emami

2014-01-01

333

[Malignant cardiac tumors].  

PubMed

Cardiac neoplasms are a rare occurrence in clinical practice. The various frequencies of primary and secondary malignant tumors vary from report to report, approximately 1% in most autopsy series and 4% in cancer patient's autopsies. Cardiac malignancies account for less 1% of cardiac surgery and about for 0.1% of cardiac echographic studies. The presence of metastatic tumor to the heart usually indicates widespread metastases. Lung carcinomas are the most commonly encountered tumor followed by breast and pancreas cancer and melanoma. Apart from primary pericardial mesothelioma, primary cardiac tumors are high-grade sarcomas with a high metastatic potency that often becomes evident early after surgery. Symptoms are non specific, occur late in the disease and affect few patients; especially secondary neoplasms of the heart take their course so fast that they cannot become symptomatic. The signs of cardiac neoplasms are divided into systemic symptoms (fever, arthralgias and myalgias), cardiac symptoms (congestive heart failure, arrhythmia, chest pain) and uncommon embolisms. Diagnosis is actually made easier with cardiac echography. Cardiac RMI is helpful to estimate vessels and pericardium involvement. Due to its poor prognosis, treatment of cardiac metastases is restricted to best supportive care. For primary cardiac neoplasms, surgery must be carefully discussed because operative intervention is often followed by rapid widespread metastases that adjuvant chemotherapy cannot avoid in most cases. PMID:15899620

Debourdeau, Philippe; Gligorov, Joseph; Teixeira, Luis; Aletti, Marc; Zammit, Christine

2004-11-01

334

Cardiac disease after radiation therapy for Hodgkin's disease: analysis of 48 patients  

SciTech Connect

Occult or overt but delayed cardiac disease after thoracic radiotherapy for Hodgkin's disease may be common. Detailed cardiac evaluations were performed in 48 patients with Hodgkin's disease at risk a mean of 97 months after radiotherapy. The study protocol included echocardiography, gated radionuclide ventriculography, and cardiac catheterization. Cardiac disease was found in 46 patients (96%) and included constrictive or occult constrictive pericarditis (24 patients), an abnormal hemodynamic response to a fluid challenge (14 patients), coronary artery disease (6 patients), and left ventricular dysfunction (2 patients). Most patients (53%) had normal echocardiograms. Gated blood pool radionuclide angiocardiography was performed in 42 patients. Excluding patients with occlusive coronary artery disease, the left ventricular ejection fraction at rest (mean 59%) and during exercise (mean 69%) was within normal limits. Thus (1) delayed cardiac disease after radiotherapy is common, (2) chronic pericardial disorders are the most frequent manifestations of this disease, and (3) the prognosis for patients who have radiation-induced cardiac disease is generally favorable.

Applefeld, M.M.; Wiernik, P.H.

1983-06-01

335

The left ventricular apex is the optimal site for pediatric pacing: correlation with animal experience.  

PubMed

Pacing at the commonly used right ventricular (RV) apex results in impaired ventricular performance. Previous animal studies indicated that the left ventricular (LV) apex is a superior pacing site. The purpose of this study was to investigate in dogs whether this good performance is associated with a more synchronous electrical activation pattern of the LV and whether the LV apex is also a good pacing site in children. In 11 healthy dogs and 8 children undergoing cardiac surgery, dual chamber pacing was performed at the RV apex, LV apex and LV lateral free wall (LVFW). In dogs, a basket electrode was inserted into the LV to assess pattern and timing of LV endocardial activation. In the children, hemodynamic measurements were performed immediately after recovery from cardiopulmonary bypass. In dogs, LV apex pacing resulted in synchronous activation around the LV circumference whereas RV apex and LVFW pacing resulted in asynchrony of activation between the septum and LVFW. In both canine and children's hearts most hemodynamic variables remained at sinus rhythm level during LV apex pacing, but LVdPdtmax, stroke work (dogs), and pulse pressure (children) were reduced as compared with sinus rhythm during RV apex and LVFW pacing. LV apex pacing results in synchronous activation of the LV and is, in adult dogs and in children, associated with superior hemodynamic performance. PMID:15189513

Vanagt, Ward Y; Verbeek, Xander A; Delhaas, Tammo; Mertens, Luc; Daenen, Willem J; Prinzen, Frits W

2004-06-01

336

The LIM protein fhlA is essential for heart chamber development in zebrafish embryos.  

PubMed

Four-and-a-half LIM proteins FHL1-3 play important roles in cardiovascular pathophysiology. However, their roles in heart development remain unclear. Here, we report that fhlA, the zebrafish homolog of human FHL1, was found to be expressed around the 22-somite stage. After 24 hpf, expression was restricted to the heart. fhlA knockdown caused an enlarged cardiac chamber phenotype with up-regulated expression of the cardiac markers, but fhlA overexpression reduced the sizes of the cardiac chambers and down-regulated expression of the markers. The morphology associated with the cmlc2, amhc, and vmhc expression patterns at the 22 somite and 24 hpf stages included a broadened domain in embryos lacking fhlA and a smaller domain in embryos overexpressing fhlA. The changes in the sizes of the chambers were attributed to the changes in the number of ventricular and atrial cells. Loss of fhlA caused a longer heart period and pause between heartbeats in M-modes than in controls, but fhlA overexpression caused shorter systolic and diastolic intervals. Abnormal cardiac chambers and physiological function were found to be largely rescued. We also showed the expression of fhlA in the heart to be increased by retinoic acid (RA) and decreased by the RA synthase inhibitor DEAB. Both fhlA and RA signaling caused a phenotype characterized by the morphological alterations in the chamber sizes, suggesting that the role of fhlA in heart development is probably regulated by RA signaling. Taken together, these results showed that fhlA regulates the size of the heart chamber by reducing the number of cardiac cells. PMID:23438903

Xie, H; Fan, X; Tang, X; Wan, Y; Chen, F; Wang, X; Wang, Y; Li, Y; Tang, M; Liu, D; Jiang, Z; Liu, X; Yuan, W; Li, G; Ye, X; Zhou, J; Mo, X; Deng, Y; Wu, X

2013-07-01

337

Late onset oral treatment with tranilast following large myocardial infarction has no beneficial effects on cardiac remodeling and mortality in rats  

PubMed Central

Tranilast (Tra) reduces intracardiac interstitial fibrosis in the animal models of hypertensive heart failure and diabetic cardiomyopathy by inhibiting cardiac fibroblasts. The present study examined whether Tra has long-term effects on the cardiac remodeling in the remote area of the left ventricle (LV) following myocardial infarction (MI) in the rat. Treatment with Tra (n=40; 150 mg/kg twice daily) or placebo (Plac, n=36) was started at day 28 after induction of a large MI or sham-operation (ShO, n=18) in female Lewis rats. Collagen content was determined using high-performance liquid chromatography. Large MI led to a significant hypertrophy of the two ventricles, a severe dilatation of the LV and a shift of the chamber stiffness variables in the pressure volume curves. The six-month survival rates were Tra, 62.5%; Plac, 75%; and ShO, 100%. No significant difference was identified between Tra and Plac regarding survival rate and collagen content. Treatment with the anti-inflammatory and antifibrotic drug, Tra, started four weeks after the induction of a large MI in the rat, did not attenuate or positively influence remodeling in chronic ischemic heart failure and survival. Further studies are required to explore the effects of Tra on cardiac myocytes post-MI in more detail. PMID:25371734

BETGE, STEFAN; KUNZ, CHRISTIAN; FIGULLA, HANS; JUNG, CHRISTIAN

2014-01-01

338

Through the looking glass: primary epithelioid angiosarcoma in the left atrium, a unique site for a rare malignancy.  

PubMed

Malignant cardiac tumours occurring on the left side are vanishingly rare entities. We describe a case of a 73-year-old male who underwent surgery for a left-sided cardiac tumour following initial presentation with transient ischaemic attacks. In addition to the unusual presentation and subsequent metastatic pattern to the femur, the tumour's pathological diagnosis was that of an epithelioid variant of an angiosarcoma which has not been previously described in this anatomical location. PMID:23331275

Hynes, Sean O; Attah, Chike B; Ingoldsby, Helen; Kolcow, Walenty; Macneill, Briain; Veerasingam, Dave; Orosz, Zsolt

2013-07-01

339

Hypothyroidism and its rapid correction alter cardiac remodeling.  

PubMed

The cardiovascular effects of mild and overt thyroid disease include a vast array of pathological changes. As well, thyroid replacement therapy has been suggested for preserving cardiac function. However, the influence of thyroid hormones on cardiac remodeling has not been thoroughly investigated at the molecular and cellular levels. The purpose of this paper is to study the effect of hypothyroidism and thyroid replacement therapy on cardiac alterations. Thirty Wistar rats were divided into 2 groups: a control (n?=?10) group and a group treated with 6-propyl-2-thiouracil (PTU) (n?=?20) to induce hypothyroidism. Ten of the 20 rats in the PTU group were then treated with L-thyroxine to quickly re-establish euthyroidism. The serum levels of inflammatory markers, such as C-reactive protein (CRP), tumor necrosis factor alpha (TNF-?), interleukin 6 (IL6) and pro-fibrotic transforming growth factor beta 1 (TGF-?1), were significantly increased in hypothyroid rats; elevations in cardiac stress markers, brain natriuretic peptide (BNP) and cardiac troponin T (cTnT) were also noted. The expressions of cardiac remodeling genes were induced in hypothyroid rats in parallel with the development of fibrosis, and a decline in cardiac function with chamber dilation was measured by echocardiography. Rapidly reversing the hypothyroidism and restoring the euthyroid state improved cardiac function with a decrease in the levels of cardiac remodeling markers. However, this change further increased the levels of inflammatory and fibrotic markers in the plasma and heart and led to myocardial cellular infiltration. In conclusion, we showed that hypothyroidism is related to cardiac function decline, fibrosis and inflammation; most importantly, the rapid correction of hypothyroidism led to cardiac injuries. Our results might offer new insights for the management of hypothyroidism-induced heart disease. PMID:25333636

Hajje, Georges; Saliba, Youakim; Itani, Tarek; Moubarak, Majed; Aftimos, Georges; Farès, Nassim

2014-01-01

340

Hypothyroidism and Its Rapid Correction Alter Cardiac Remodeling  

PubMed Central

The cardiovascular effects of mild and overt thyroid disease include a vast array of pathological changes. As well, thyroid replacement therapy has been suggested for preserving cardiac function. However, the influence of thyroid hormones on cardiac remodeling has not been thoroughly investigated at the molecular and cellular levels. The purpose of this paper is to study the effect of hypothyroidism and thyroid replacement therapy on cardiac alterations. Thirty Wistar rats were divided into 2 groups: a control (n?=?10) group and a group treated with 6-propyl-2-thiouracil (PTU) (n?=?20) to induce hypothyroidism. Ten of the 20 rats in the PTU group were then treated with L-thyroxine to quickly re-establish euthyroidism. The serum levels of inflammatory markers, such as C-reactive protein (CRP), tumor necrosis factor alpha (TNF-?), interleukin 6 (IL6) and pro-fibrotic transforming growth factor beta 1 (TGF-?1), were significantly increased in hypothyroid rats; elevations in cardiac stress markers, brain natriuretic peptide (BNP) and cardiac troponin T (cTnT) were also noted. The expressions of cardiac remodeling genes were induced in hypothyroid rats in parallel with the development of fibrosis, and a decline in cardiac function with chamber dilation was measured by echocardiography. Rapidly reversing the hypothyroidism and restoring the euthyroid state improved cardiac function with a decrease in the levels of cardiac remodeling markers. However, this change further increased the levels of inflammatory and fibrotic markers in the plasma and heart and led to myocardial cellular infiltration. In conclusion, we showed that hypothyroidism is related to cardiac function decline, fibrosis and inflammation; most importantly, the rapid correction of hypothyroidism led to cardiac injuries. Our results might offer new insights for the management of hypothyroidism-induced heart disease. PMID:25333636

Itani, Tarek; Moubarak, Majed; Aftimos, Georges; Fares, Nassim

2014-01-01

341

Chapter 13. No Watt Left Behind No Watt Left Behind  

E-print Network

Chapter 13. No Watt Left Behind 13-1 No Watt Left Behind Academic and Research Staff Professor. No Watt Left Behind 13-2 RLE Progress Report 152 solve equipment failures and problems, and to facilitate, Jose Cruz, EECS Technical and Support Staff Denise Stewart, Administrative Assistant 1. No Watt Left

342

Iran Chamber Society  

NSDL National Science Digital Library

In 2001, the Iran Chamber Society was created in order to provide a non-partisan, non-commercial, comprehensive source of information on Iran. The website's "About Us" section states that their aim is to "create a global awareness about Iranian society and eradicate the misunderstandings and misconceptions about Iranian society, and to play an educational role as well." Visitors will find the website divided up into "Art and Culture", "History", "Society" and "Iran's Guide". The "Exhibitions and Conferences" link on the right side of the homepage leads visitors to a number of exhibitions, including the fascinating "Artistic Murals of Tehran's Metro Stations", which offers a dozen pictures of the beautifully handcrafted murals made of pottery, metal, cement and other materials. The "History" section offers pictures and documents, including some disturbing graphic photos from the Iran-Iraq War in 1980-1988 that appear at the end of the Historic Periods and Events section.

343

Impact of obesity and weight loss on cardiac performance and morphology in adults.  

PubMed

Obesity, particularly severe obesity is capable of producing hemodynamic alterations that predispose to changes in cardiac morphology and ventricular function. These include increased cardiac output, left ventricular hypertrophy and diastolic and systolic dysfunction of both ventricles. Facilitated by co-morbidities such as hypertension, the sleep apnea/obesity hypoventilation syndrome, and possibly certain neurohormonal and metabolic alterations, these abnormalities may predispose to left and right heart failure, a disorder known as obesity cardiomyopathy. PMID:24438730

Alpert, Martin A; Omran, Jad; Mehra, Ankit; Ardhanari, Sivakumar

2014-01-01

344

Modification of cardiac function in cirrhotic patients with and without ascites  

Microsoft Academic Search

OBJECTIVES:Abnormalities in cardiac function have been reported in liver cirrhosis, suggesting a latent cardiomyopathy in these patients. In this study we investigated cardiac function in cirrhotic patients and in controls.METHODS:A total of 20 cirrhotic patients without previous or ongoing ascites, 20 cirrhotic patients with moderate-to-severe ascites, and 10 healthy controls were studied by two-dimensional Doppler echocardiography. Cardiac dimensions and left

Valentina Valeriano; Stefania Funaro; Raffaella Lionetti; Oliviero Riggio; Giovanna Pulcinelli; Pierluigi Fiore; Andrea Masini; Stefano De Castro; Manuela Merli

2000-01-01

345

A rare case of anomalous left coronary artery from the pulmonary artery (ALCAPA) presenting congestive heart failure in an adult  

Microsoft Academic Search

A 41-year-old woman with no modifiable coronary risk factors presented with a progressive exertional dyspnea. Chest radiography showed an enlarged cardiac silhouette with reinforced pulmonary vasculature in bilateral lower lung fields and both pleural effusion. Echocardiography revealed a dilated, globally hypokinetic left ventricle with an ejection fraction of 40%. Multislice cardiac computed tomography revealed abnormal origin of LCA from the

Woong Chol Kang; Wook-Jin Chung; Chang Hyu Choi; Kook Yang Park; Mi Jin Jeong; Tae Hoon Ahn; Eak Kyun Shin

2007-01-01

346

Assessment of Global Cardiac Function in MSCT Imaging Using Fuzzy Connectedness Segmentation  

E-print Network

and with a high spatial resolution, 3D dynamic images of cardiac walls and cavities and of coronary ves- sels global 3D quantitative parameters are extracted to describe the left cardiac func- tion. Several MRI [10]. Multi-agent approaches have also been considered for the analysis of brain images [11

Paris-Sud XI, Université de

347

Cardiac Effects of SlowRelease Lanreotide, a Slow Release Somatostatin Analog, in Acromegalic Patients  

Microsoft Academic Search

Cardiac involvement, mostly characterized by left ventricular hy- pertrophy associated with various degrees of cardiac dysfunction, greatly contributes to the increased mortality and morbidity observed in acromegaly. Lanreotide is a new SRIF analog characterized by a slow-release (SR) formulation with the peculiarity of a 30-mg im administration every 10 -14 days. In this study, 13 patients with postoperative active acromegaly

ROBERTO BALDELLI; ELISABETTA FERRETTI; MARIE-LISE JAFFRAIN-REA; GIANLUCA IACOBELLIS; GIUSEPPE MINNITI; BARBARA CARACCIOLO; CARLO MORONI; ROSARIO CASSONE; ALBERTO GULINO; GUIDO TAMBURRANO

348

The Juelich large Aerosol Chamber  

Microsoft Academic Search

The large Aerosol Chamber is designed for the investigation of nighttime atmospheric chemistry. The Aerosol Chamber is a dark chamber and is operated at ambient temperature and pressure conditions. It is constructed as a double wall system: a fully welded aluminum box (7m x 7m x 5.3m) and an equally sized fully heat sealed Teflon bag hanging from the ceiling.

Th. Mentel; A. Wahner; M. Folkers

2003-01-01

349

Motion tracking of left ventricle and coronaries in 4D CTA  

NASA Astrophysics Data System (ADS)

In this paper, we present a novel approach for simultaneous motion tracking of left ventricle and coronary arteries from cardiac Computed Tomography Angiography (CTA) images. We first use the multi-scale vesselness filter proposed by Frangi et al.1 to enhance vessels in the cardiac CTA images. The vessel centrelines are then extracted as the minimal cost path from the enhanced images. The centrelines at end-diastolic (ED) are used as prior input for the motion tracking. All other centrelines are used to evaluate the accuracy of the motion tracking. To segment the left ventricle automatically, we perform three levels of registration using a cardiac atlas obtained from MR images. The cardiac motion is derived from cardiac CTA sequences by using local-phase information to derive a non-rigid registration algorithm. The CTA image at each time frame is registered to the ED frame by maximising the proposed similarity function and following a serial registration scheme. Once the images have been aligned, a dynamic motion model of the left ventricle can be obtained by applying the computed free-form deformations to the segmented left ventricle at ED phase. A similar propagation method also applies to the coronary arteries. To validate the accuracy of the motion model we compare the actual position of the coronaries and left ventricle in each time frame with the predicted ones as estimated from the proposed tracking method.

Zhang, Dong Ping; Zhuang, Xiahai; Ourselin, Sebastien; Rueckert, Daniel

2011-03-01

350

Berberine attenuates cardiac dysfunction in hyperglycemic and hypercholesterolemic rats.  

PubMed

The positive effects of berberine (30 mg/kg/day, i.g. for 6 weeks) on cardiac dysfunction were evaluated in the rat model of hyperglycemia and hypercholesterolemia. Hyperglycemia and hypercholesterolemia were induced by feeding high-sucrose/fat diet (HSFD) consisting of 20% sucrose, 10% lard, 2.5% cholesterol, 1% bile salt for 12 weeks and streptozotocin (30 mg/kg, i.p.). The plasma sugar, total cholesterol, and triglyceride levels were significantly increased (422, 194 and 82%, respectively) in the HSFD/streptozotocin-treated rats, when compared with control animals receiving normal diet and vehicle. Berberine treatment reduced the plasma sugar and lipid levels by 24-69% in the rat model of hyperglycemia and hypercholesterolemia. Cardiac functions signed as values of cardiac output, left ventricular systolic pressure, the maximum rate of myocardial contraction (+dp/dtmax), left ventricular end diastolic pressure and the maximum rate of myocardial diastole (-dp/dtmax) were injured by 16-55% in the hyperglycemic/hypercholesterolemic rats. Berberine increased cardiac output, left ventricular systolic pressure and +dp/dtmax by 64, 16 and 79%, but decreased left ventricular end diastolic pressure and -dp/dtmax by 121 and 61% in the rats receiving HSFD/streptozotocin, respectively, when compared with the drug-untreated rats of hyperglycemia and hypercholesterolemia. Berberine caused significant increase in cardiac fatty acid transport protein-1 (159%), fatty acid transport proteins (56%), fatty acid beta-oxidase (52%), as well as glucose transporter-4 and peroxisome proliferator-activated receptor-? (PPAR?), but decrease in PPAR? mRNA and protein expression in hyperglycemic/hypercholesterolemic rats. These results indicated that berberine exerted protective effects on cardiac dysfunction induced by hyperglycemia/hypercholesterolemia through alleviating cardiac lipid accumulation and promoting glucose transport. PMID:21458442

Dong, Shi-Fen; Hong, Ying; Liu, Ming; Hao, Ying-Zhi; Yu, Hai-Shi; Liu, Yang; Sun, Jian-Ning

2011-06-25

351

No Watt Left Behind  

Microsoft Academic Search

More generally, at any point in the life of a building, mechanical and electrical equipment - the services infrastructure - may be poorly operated. Equipment may be inadvertently left in operation when not needed: lights and fans running all night or air conditioning in unoccupied spaces. Or equipment may be operated in ignorance of the cost, a problem exacerbated by

Steven Leeb; James L. Kirtley; Les K. Norford

352

Left or Right?  

Microsoft Academic Search

In discussing the situation that prevails in the Socialist Party of the United States at the present time it is hardly accurate to refer to the two parties to the controversy as Left and Right, at least in the European sense of those terms. The American Socialist move- ment has had, in the crisis through which it has just passed,

Ludwig Lore

353

The Children Left Behind  

ERIC Educational Resources Information Center

This article explores some of the deficits in our educational system in regard to non-hearing students. It has become agonizingly clear that non-hearing students are being left out of the gallant sweep to enrich our children's educations. The big five areas of literacy, at best, present unique challenges for non-hearing students and, in some…

Gillard, Sarah A.; Gillard, Sharlett

2012-01-01

354

No Adult Left Behind  

ERIC Educational Resources Information Center

Left out of the conversation for education reform, at least on the level of grade school, secondary school, and college are the adult education programs provided across the country. These programs receive a fraction of the funds and respect as mainstream programs do. However, they are sorely needed in Northwest Indiana. The region's early 21st…

Arndt, Jason

2010-01-01

355

Accountability Left Behind  

ERIC Educational Resources Information Center

This article describes the reversal of the dismissal of an "unfunded-mandates" challenge to the No Child Left Behind Act (NCLB) brought by the National Education Association (NEA), several of its affiliates, and a number of school districts by the United States Court of Appeals for the Sixth Circuit. The decision in "School District of the City of…

Testani, Rocco E.; Mayes, Joshua A.

2008-01-01

356

No Community Left Behind  

ERIC Educational Resources Information Center

The debate over the reauthorization of No Child Left Behind (NCLB) generally overlooks--or looks past--what may be the most fundamental flaw in that legislation. As the law is now written, decisions regarding what the young should know and be able to do are removed from the hands of parents and local community leaders and turned over to officials…

Schlechty, Phillip C.

2008-01-01

357

No Child Left Inside  

NSDL National Science Digital Library

Earth Science Week (ESW) 2008 encourages people around the globe to open doors and investigate new opportunities. This year's theme, "No Child Left Inside," is a call to explore our natural environments. The celebration urges everyone--especially young people--to venture outdoors and experience Earth science firsthand.

Benbow, Ann E.; Camphire, Geoff

2008-09-01

358

No Child Left Inside!  

NSDL National Science Digital Library

Earth Science Week (ESW) 2008 encourages people around the globe to open doors and investigate new opportunities. This year's theme, "No Child Left Inside," is a call to explore our natural environments. The celebration urges everyone--especially young people--to venture outdoors and experience Earth science firsthand.

Benbow, Ann E.; Camphire, Geoff

2008-09-01

359

Emergency cardiac support with extracorporeal membrane oxygenation for cardiac arrest.  

PubMed

A 46-year-old woman with no major medical history presented to the emergency department with chest pain and evidence of anterior, anterolateral, and inferior ST-elevation myocardial infarction. Her condition quickly deteriorated into cardiogenic shock with ventricular arrhythmia. Despite revascularization of the left anterior descending artery and intravenous inotrope and antiarrhythmic therapy, her unstable hemodynamics and arrhythmias persisted. Early emergency initiation of venoarterial extracorporeal membrane oxygenation (ECMO) led to prompt hemodynamic and rhythm stability; however, adequate endogenous cardiac output did not ensue, and she was not able to be weaned from ECMO until hospital day 8. She subsequently recovered and continues to do well in the outpatient setting. This case demonstrates the remarkable hemodynamic and rhythm stability that early initiation of ECMO can provide in the setting of unstable myocardial infarction. PMID:23809321

Tweet, Marysia S; Schears, Gregory J; Cassar, Andrew; Sheldon, Seth H; McGlinch, Brian P; Sandhu, Gurpreet S

2013-07-01

360

Anomalous left coronary artery arising from the pulmonary artery.  

PubMed

A 24-year-old female presented to her general practitioner with shortness of breath. She was referred for an echocardiogram, which demonstrated features suggestive of a right coronary artery fistula, and referred to our institute. We performed a contrast-enhanced, prospectively triggered cardiac CT angiogram, which demonstrated the primary and secondary features of anomalous left coronary artery arising from the pulmonary artery (ALCAPA), also known as the Bland-White-Garland syndrome, a rare congenital abnormality of the origin of the left main coronary artery. PMID:23044529

Durand, M; Nguyen, E T; Crean, A M

2012-09-01

361

Bicameral repair of right pulmonary artery to left atrial communication.  

PubMed

A right pulmonary artery to left atrial communication is a very rare vascular congenital anomaly. Patients most commonly present in the neonatal period with congestive cardiac failure or at a later stage with central cyanosis and its complications. Various diagnostic modalities are available but angiography is the most important decision-making tool for the management of this lesion. We present an unusual case of right pulmonary artery to left atrial communication in a 14-year-old patient, who underwent successful surgical repair through a bicameral approach. PMID:21692017

Gajjar, T P; Desai, N B

2012-04-01

362

Cantrell's Syndrome with left ventricular diverticulum: a case report.  

PubMed

Congenital left ventricular diverticulum is a rare condition. When found, it is usually accompanied by other intracardiac malformations, so that again further examination is indicated. Furthermore, it is usually associated with thoracoabdominal wall defect, as seen in the spectrum of Cantrell's pentalogy, a congenital anomaly consisting of a lower sternal defect, diastasis recti, pericardial defect, anterior diaphragmatic hernia and cardiac malformation. This paper reports a case of Cantrell's Syndrome with left ventricular diverticulum. Successful total correction of ventricular diverticulum, ventricular defects and diastasi recti, was performed at two years of age. The clinical features, ambryology and surgical management of these defects are discussed. PMID:23422578

Manieri, S; Adurno, G; Iorio, F; Tomasco, B; Vairo, U

2013-02-01

363

HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HATCH CONNECTING TEMPERED AIR CHAMBER AND HOT AIR CHAMBER OF PLENUM WITH ATTACHED DRAFT REGULATOR. - Hot Springs National Park, Bathhouse Row, Superior Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

364

Mathematical modeling applied to the left ventricle of heart  

E-print Network

Background: How can mathematics help us to understand the mechanism of the cardiac motion? The best known approach is to take a mathematical model of the fibered structure, insert it into a more-or-less complex model of cardiac architecture, and then study the resulting fibers of activation that propagate through the myocardium. In our paper, we have attempted to create a novel software capable of demonstrate left ventricular (LV) model in normal hearts. Method: Echocardiography was performed on 70 healthy volunteers. Data evaluated included: velocity (radial, longitudinal, rotational and vector point), displacement (longitudinal and rotational), strain rate (longitudinal and circumferential) and strain (radial, longitudinal and circumferential) of all 16 LV myocardial segments. Using these data, force vectors of myocardial samples were estimated by MATLAB software, interfaced in the echocardiograph system. Dynamic orientation contraction (through the cardiac cycle) of every individual myocardial fiber could ...

Ranjbar, Saeed

2014-01-01

365

Isolated left ventricular diastolic collapse in pericardial tamponade: an uncommon echocardiographic finding.  

PubMed

A case of circumferential moderate pericardial effusion causing isolated collapse of left ventricular cavity on two-dimensional echocardiography is reported. Pericardial effusion, mostly of infective etiology, is relatively common in this part of the world. When large enough to cause tamponade, collapse of right atrium, right ventricle, and uncommonly left atrium can be seen. Left ventricular collapse is rare, both due to the larger muscle mass and higher chamber pressure. PMID:24919444

Singh, Vikas; Dwivedi, Sudhanshu K; Chandra, Sharad; Sanguri, Ritesh; Saran, Ram Kirti

2014-08-01

366

Pyopericardium complicated with cardiac tamponade: an unusual presenting manifestation of primary pyomyositis.  

PubMed

Primary pyomyositis is an infective condition mainly involving the skeletal muscles. Various cardiac complications reported are acute bacterial endocarditis, pyogenic pericarditis, pancarditis and, very rarely, pyopericardium presenting as cardiac tamponade. We report a case of 15-year-old boy presenting with complaints of fever, progressive shortness of breath and retrosternal pleuritic chest pain. He also complained of painful swellings of left arm, left side of neck and left thigh extending up to the knee joint. Ultrasonography showed collections in the: bilateral sternocleidomastoid; subclavius; left thigh muscles; and left knee joint. Echocardiography showed evidence of cardiac tamponade. He underwent emergent pericardiocentesis and frank pus was drained. Pus culture grew Methicillin resistant Staphylococcous aureus. With drainage and the appropriate antibiotics, he improved. PMID:23550203

Kumar, Susheel; Sharma, Navneet; Singh, Rajveer; Bhalla, Ashish; Varma, Subhash

2013-01-01

367

Postoperative hemodynamics after norwood palliation for hypoplastic left heart syndrome  

Microsoft Academic Search

Hemodynamics after Norwood palliation for hypoplastic left heart syndrome (HLHS) have been incompletely characterized, although emphasis has been placed on the role that an excess pulmonary-to-systemic blood flow ratio (Qp\\/Qs) may play in causing hemodynamic instability. Studies suggest that maximal oxygen delivery occurs at a Qp\\/Qs <1. However, it remains unclear to what extent cardiac output can increase with increasing

John R Charpie; Mary K Dekeon; Caren S Goldberg; Ralph S Mosca; Edward L Bove; Thomas J Kulik

2001-01-01

368

Stretch of contracting cardiac muscle abruptly decreases the rate of phosphate release at high and low calcium.  

PubMed

The contractile performance of the heart is linked to the energy that is available to it. Yet, the heart needs to respond quickly to changing demands. During diastole, the heart fills with blood and the heart chambers expand. Upon activation, contraction of cardiac muscle expels blood into the circulation. Early in systole, parts of the left ventricle are being stretched by incoming blood, before contraction causes shrinking of the ventricle. We explore here the effect of stretch of contracting permeabilized cardiac trabeculae of the rat on the rate of inorganic phosphate (P(i)) release resulting from ATP hydrolysis, using a fluorescent sensor for P(i) with millisecond time resolution. Stretch immediately reduces the rate of P(i) release, an effect observed both at full calcium activation (32 ?mol/liter of Ca(2+)), and at a physiological activation level of 1 ?mol/liter of Ca(2+). The results suggest that stretch redistributes the actomyosin cross-bridges toward their P(i)-containing state. The redistribution means that a greater fraction of cross-bridges will be poised to rapidly produce a force-generating transition and movement, compared with cross-bridges that have not been subjected to stretch. At the same time stretch modifies the P(i) balance in the cytoplasm, which may act as a cytoplasmic signal for energy turnover. PMID:22692210

Mansfield, Catherine; West, Tim G; Curtin, Nancy A; Ferenczi, Michael A

2012-07-27

369

Left ventricular mural thrombus  

SciTech Connect

The identification of mural thrombus in patients with left ventricular aneurysm and mural thrombus probably warrants consideration of long-term anticoagulation. In patients with acute, large, anterior or anteroapical, transmural myocardial infarctions, serial noninvasive examinations are warranted to define a group of patients at high risk for the development of left ventricular aneurysm and/or mural thrombus. Anticoagulants should be considered in patients in whom mural thrombi develop as a complication of their infarction. Patients with congestive cardiomyopathy should be considered for long-term anticoagulation. These recommendations are all tempered by the realization that the use of anticoagulant therapy is not without its own risks. The decision to anticoagulate must be balanced against each individual patient's suitability for such therapy and the individual likelihood of the development of side effects.

Nixon, J.V.

1983-08-01

370

Diabetes mellitus and cardiac function.  

PubMed

Cardiovascular complications are the most common causes of morbidity and mortality in diabetic patients. Coronary atherosclerosis is enhanced in diabetics, whereas myocardial infarction represents 20% of deaths of diabetic subjects. Furthermore, re-infarction and heart failure are more common in the diabetics. Diabetic cardiomyopathy is characterized by an early diastolic dysfunction and a later systolic one, with intracellular retention of calcium and sodium and loss of potassium. In addition, diabetes mellitus accelerates the development of left ventricular hypertrophy in hypertensive patients and increases cardiovascular mortality and morbidity. Treating the cardiovascular problems in diabetics must be undertaken with caution. Special consideration must be given with respect to the ionic and metabolic changes associated with diabetes. For example, although ACE inhibitors and calcium channel blockers are suitable agents, potassium channel openers cause myocardial preconditioning and decrease the infarct size in animal models, but they inhibit the insulin release after glucose administration in healthy subjects. Furthermore, potassium channel blockers abolish myocardial preconditioning and increase infarct size in animal models, but they protect the heart from the fatal arrhythmias induced by ischemia and reperfusion which may be important in diabetes. For example, diabetic peripheral neuropathy usually presents with silent ischemia and infarction. Mechanistically, parasympathetic cardiac nerve dysfunction, expressed as increased resting heart rate and decreased respiratory variation in heart rate, is more frequent than the sympathetic cardiac nerve dysfunction expressed as a decrease in the heart rate rise during standing. PMID:9546631

Mahgoub, M A; Abd-Elfattah, A S

1998-03-01

371

An apical left ventricular aneurysm rupture presenting as left breast mass 11 years after surgical repair.  

PubMed

Left ventricular (LV) pseudoaneurysm is a rare entity and, consequently, there is limited knowledge of the condition's natural history. The most frequent mode of presentation for LV pseudoaneurysm is heart failure with chest pain. However, the variable presentation of this condition requires a high index of suspicion for diagnosis. We report the case of a 75-year-old woman who had suffered an acute myocardial infarction 23 years previously, which resulted in a calcified LV apical aneurysm. Three weeks prior to being referred to our hospital, she was noted by her general practitioner to have a left-sided breast mass although mammography was negative. One week later, she attended the accident and emergency department; she was haemodynamically unstable but was resuscitated successfully. Contrast enhanced computed tomography showed a large haematoma located in the left chest wall communicating with the left ventricle. She underwent emergency cardiac surgical repair. On arrival at the intensive care unit following surgery, her haemodynamic status was unstable, and she deteriorated rapidly and died. With this report, we aim to raise the level of awareness for an apical LV pulsatile mass that could anatomically expand and present as a breast mass or tumour. An early diagnosis and timely surgical intervention is essential in order to achieve better outcomes and avoid detrimental complications. PMID:25245713

Fok, M; Bashir, M; Hammoud, I; Harrington, D; Kuduvalli, M; Field, M; Oo, A

2014-10-01

372

[Clinical application of image processing system and quantitative analysis of left ventriculogram and coronary arteriogram].  

PubMed

Currently cine left ventriculography and coronary arteriography are still one of the most important methods in the diagnosis of coronary heart disease and other coronary arterial diseases. An image processing system, called "IA-87 Medical Image Processing System", for quantitative analysis of cine-coronary and left ventricular angiograms has been developed using IBM-PC/AT computer. The major functions of this system are: (1) left ventricular volume determination, i.e. left ventricular contour can be drawn automatically or semi-automatically, the systolic and diastolic volume of the left ventricle are calculated by Simpson's, length-area and chord-length methods. (2) left ventricular segmental wall motion analysis, using rectilinear and polar method, the segmental ejection fraction and normalized segmental contraction are determined. (3) dynamic display of the cardiac cycle. (4) coronary arterial lesion, such as stenosis, can be quantitatively analysed. In a series of cases free from cardiac disease the normal coronary artery (40 cases) and left ventricle (30 cases) were quantitatively analysed using "IA-87 Medical Image Processing System", and the normal value of coronary artery diameter and left ventricular function among Chinese obtained. At the same time, in a series of 45 cases with coronary heart disease (including anterior, posterior wall infarction, and left ventricular aneurysm in 15 respectively), quantitative analysis of the left ventricle was made. The results showed that the system is of significant value for quantitative diagnosis of ischemic heart disease as well as evaluation of therapeutic effect and prediction of prognosis. PMID:1879318

Dai, R

1991-04-01

373

Cardiac function in patients with cystic fibrosis: evaluation by two-dimensional and Doppler echocardiography.  

PubMed

Two-dimensional and Doppler echocardiography were performed in 17 consecutive hospitalized patients with cystic fibrosis aged 6 to 38 years (mean 21 +/- 9) and in 10 normal subjects aged 24 +/- 7 years. Left ventricular and right ventricular ejection fraction were measured by a computerized light pen system and Simpson's rule from two-dimensional echocardiographic apical four and two chamber views. Right ventricular wall thickness, inferior vena cava size and the presence of tricuspid regurgitation by Doppler recording were also assessed. National Institutes of Health (NIH) score of clinical severity ranged from 22 to 72 (mean 51 +/- 15) (100 = excellent, 0 = poor). Four patients, all with an NIH score of 40 or less, died of respiratory failure within 1 year of the echocardiographic study. There was no significant difference between patients with cystic fibrosis and normal subjects with regard to right ventricular ejection fraction (59 +/- 11 versus 61 +/- 10%), left ventricular ejection fraction (67 +/- 8 versus 70 +/- 8%) and right ventricular systolic (5 +/- 1 versus 5 +/- 0.5 mm) and diastolic (2.4 +/- 0.5 versus 2.5 +/- 0.5 mm) wall thicknesses. A dilated inferior vena cava and mild tricuspid regurgitation by Doppler recording were detected in only one patient. A poor correlation was found between right ventricular ejection fraction and NIH clinical score (r = 0.26), chest X-ray score (r = 0.29) and pulmonary function tests. It is concluded that right and left ventricular systolic function is preserved in patients with moderately severe cystic fibrosis; clinical status in these patients is probably determined by the pulmonary rather than cardiac involvement. PMID:4031283

Panidis, I P; Ren, J F; Holsclaw, D S; Kotler, M N; Mintz, G S; Ross, J

1985-09-01

374

Proton beam monitor chamber calibration  

NASA Astrophysics Data System (ADS)

The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences—of the order of 3%—were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth—i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers—rather than cylindrical chambers—for the reference dosimetry of pseudo-monoenergetic proton beams.

Gomà, C.; Lorentini, S.; Meer, D.; Safai, S.

2014-09-01

375

Three dimensional flow in the human left atrium  

PubMed Central

BACKGROUND—Abnormal flow patterns in the left atrium in atrial fibrillation or mitral stenosis are associated with an increased risk of thrombosis and systemic embolisation; the characteristics of normal atrial flow that avoid stasis have not been well defined.?OBJECTIVES—To present a three dimensional particle trace visualisation of normal left atrial flow in vivo, constructed from flow velocities in three dimensional space.?METHODS—Particle trace visualisation of time resolved three dimensional magnetic resonance imaging velocity measurements was used to provide a display of intracardiac flow without the limitations of angle sensitivity or restriction to imaging planes. Global flow patterns of the left atrium were studied in 11 healthy volunteers.?RESULTS—In all subjects vortical flow was observed in the atrium during systole and diastolic diastasis (mean (SD) duration of systolic vortex, 280 (77) ms; and of diastolic vortex, 256 (118) ms). The volume incorporated and recirculated within the vortices originated predominantly from the left pulmonary veins. Inflow from the right veins passed along the vortex periphery, constrained between the vortex and the atrial wall.?CONCLUSIONS—Global left atrial flow in the normal human heart comprises consistent patterns specific to the phase of the cardiac cycle. Separate paths of left and right pulmonary venous inflow and vortex formation may have beneficial effects in avoiding left atrial stasis in the normal subject in sinus rhythm.???Keywords: atrium; blood flow; magnetic resonance imaging; haemodynamics PMID:11559688

Fyrenius, A; Wigstrom, L; Ebbers, T; Karlsson, M; Engvall, J; Bolger, A

2001-01-01

376

Right atrial myxoma with a large tumor embolus in the left pulmonary artery  

PubMed Central

Cardiac myxoma, the most common primary cardiac tumor, usually develops in the left atrium. Right atrial myxomas are rare, especially those accompanied by pulmonary tumor embolism. We describe a case of a right atrial myxoma with a large tumor embolus in the left pulmonary artery. A 74-year-old man was referred to our hospital for the treatment of a right atrial tumor. Upon echocardiography, the right atrial tumor was revealed to have a mobile and tail-like surface projection. In addition, computed tomography showed that an embolus was wedged into the left pulmonary artery. We performed an emergency surgery to remove both the right atrial tumor and the pulmonary embolus. Histopathological examination revealed them both to be myxoma. Right atrial myxoma with a large pulmonary tumor embolus is a serious condition and emergency surgery to remove both cardiac tumors and pulmonary emboli should be performed to avoid the risk of sudden death. PMID:25352579

Ikeda, Akihiko; Tsukada, Toru; Konishi, Taisuke; Matsuzaki, Kanji; Jikuya, Tomoaki; Hiramatsu, Yuji

2014-01-01

377

Right atrial myxoma with a large tumor embolus in the left pulmonary artery.  

PubMed

Cardiac myxoma, the most common primary cardiac tumor, usually develops in the left atrium. Right atrial myxomas are rare, especially those accompanied by pulmonary tumor embolism. We describe a case of a right atrial myxoma with a large tumor embolus in the left pulmonary artery. A 74-year-old man was referred to our hospital for the treatment of a right atrial tumor. Upon echocardiography, the right atrial tumor was revealed to have a mobile and tail-like surface projection. In addition, computed tomography showed that an embolus was wedged into the left pulmonary artery. We performed an emergency surgery to remove both the right atrial tumor and the pulmonary embolus. Histopathological examination revealed them both to be myxoma. Right atrial myxoma with a large pulmonary tumor embolus is a serious condition and emergency surgery to remove both cardiac tumors and pulmonary emboli should be performed to avoid the risk of sudden death. PMID:25352579

Ikeda, Akihiko; Tsukada, Toru; Konishi, Taisuke; Matsuzaki, Kanji; Jikuya, Tomoaki; Hiramatsu, Yuji

2014-01-01

378

Sudden cardiac death in athletes: a case review  

Microsoft Academic Search

IntroductionCardiomyopathies are diseases of the heart muscle. The WHO defined the disorder in 1980 as ‘heart muscle disease of unknown cause’.The particular type of cardiomyopathy most connected to sports athletes and to this particular case is that of hypertrophic cardiomyopathy (HCM). HCM is characterised by left and occasionally right ventricular hypertrophy. It is the most prevalent genetic cardiac abnomality, affecting

John Kirwan; Dara Lundon; B McNeill; Deirdre Ward

2011-01-01

379

Oxidative stress reversibly inactivates myocardial enzymes during cardiac arrest.  

PubMed

Oxidative stress during cardiac arrest may inactivate myocardial enzymes and thereby exacerbate ischemic derangements of myocardial metabolism. This study examined the impact of cardiac arrest on left ventricular enzymes. Beagles were subjected to 5 min of cardiac arrest and 5 min of open-chest cardiac compressions (OCCC) before epicardial direct current countershocks were applied to restore sinus rhythm. Glutathione/glutathione disulfide redox state (GSH/GSSG) and a panel of enzyme activities were measured in snap-frozen left ventricle. To test whether oxidative stress during arrest inactivated the enzymes, metabolic (pyruvate) or pharmacological (N-acetyl-l-cysteine) antioxidants were infused intravenously for 30 min before arrest. During cardiac arrest, activities of phosphofructokinase, citrate synthase, aconitase, malate dehydrogenase, creatine kinase, glucose-6-phosphate dehydrogenase, and glutathione reductase fell by 56, 81, 55, 34, 42, 55, and 45%, respectively, coincident with 50% decline in GSH/GSSG. OCCC effected full recovery of glutathione reductase and partial recovery of citrate synthase and aconitase, in parallel with GSH/GSSG. Phosphofructokinase, malate dehydrogenase, creatine kinase, and glucose-6-phosphate dehydrogenase recovered only after cardioversion. Antioxidant pretreatments augmented phosphofructokinase, aconitase, and malate dehydrogenase activities before arrest and enhanced these activities, as well as those of citrate synthase and glucose-6-phosphate dehydrogenase, during arrest. In conclusion, cardiac arrest reversibly inactivates several important myocardial metabolic enzymes. Antioxidant protection of these enzymes implicates oxidative stress as a principal mechanism of enzyme inactivation during arrest. PMID:16920803

Sharma, Arti B; Sun, Jie; Howard, Linda L; Williams, Arthur G; Mallet, Robert T

2007-01-01

380

Close view looking to left side of statue showing left ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Close view looking to left side of statue showing left hand, shield, and laurel wreath - U.S. Capitol, Statue of Freedom, Intersection of North, South, & East Capitol Streets & Capitol Mall, Washington, District of Columbia, DC

381

Neo-intimal development on textured biomaterial surfaces during clinical use of an implantable left ventricular assist device  

Microsoft Academic Search

Implantable left ventricular assist systems are being developed for long term clinical use. Prototype devices are currently used as extended mechanical bridges to cardiac transplantation. The Therm0 Cardiosystems Inc. (TCI) pneumatic pusher plate left ventricular assist device (LVAD) features textured blood contacting sur- faces to encourage the formation of an adherent fibrin - cellular coagulum. This serves as the foundation

T. R. Graham; K. Dasse; A. Coumbe; V. Salih; M. T. Marrinan; O FRAZIER; C LEWIS

1990-01-01

382

Sudden cardiac death  

Microsoft Academic Search

The rate of cardiac deaths that are sudden is approximately 50%, and decreases with age. The causes of sudden cardiac death are diverse, and are a function of age. In children and adolescents, coronary anomalies, hypertrophic cardiomyopathy and myocarditis are frequent substrates for lethal arrhythmias; in adults, coronary atherosclerosis and acquired forms of cardiomyopathy are the most common findings at

Renu Virmani; Allen P Burke; Andrew Farb

2001-01-01

383

Hybrid Pediatric Cardiac Surgery  

Microsoft Academic Search

Minimally invasive strategies can be expanded by combining standard surgical and interventional techniques. We performed a longitudinal prospective study of all pediatric patients who have undergone hybrid cardiac surgery at the University of Chicago Children's Hospital. Hybrid cardiac surgery was defined as combined catheter-based and surgical interventions in either one setting or in a planned sequential fashion within 24 hours.

E. A. Bacha; Z. M. Hijazi; Q. L. Cao; R. Abdulla; J. P. Starr; J. Quinones; P. Koenig; B. Agarwala

2005-01-01

384

Use of wave intensity analysis of carotid arteries in identifying and monitoring left ventricular systolic function dynamics in rabbits.  

PubMed

Wave intensity analysis (WIA) of the carotid artery was conducted to determine the changes that occur in left ventricular systolic function after administration of doxorubicin in rabbits. Each randomly selected rabbit was subject to routine ultrasound, WIA of the carotid artery, cardiac catheterization and pathologic examination every week and was followed for 16 wk. The first positive peak (WI1) of the carotid artery revealed that left ventricular systolic dysfunction occurred earlier than conventional indexes of heart function. WI1 was highly, positively correlated with the maximum rate of rise in left ventricular pressure in cardiac catheterization (r = 0.94, p < 0.01) and moderately negatively correlated with the apoptosis index of myocardial cells, an indicator of myocardial damage (r = -0.69, p < 0.01). Ultrasound WIA of the carotid artery sensitively reflects early myocardial damage and cardiac function, and the result is highly consistent with cardiac catheterization findings and the apoptosis index of myocardial cells. PMID:24361226

Zhang, Hui; Zheng, Rongqin; Qian, Xiaoxian; Zhang, Chengxi; Hao, Baoshun; Huang, Zeping; Wu, Tao

2014-03-01

385

Patient-specific left atrial wall-thickness measurement and visualization for radiofrequency ablation  

NASA Astrophysics Data System (ADS)

INTRODUCTION: For radiofrequency (RF) catheter ablation of the left atrium, safe and effective dosing of RF energy requires transmural left atrium ablation without injury to extra-cardiac structures. The thickness of the left atrial wall may be a key parameter in determining the appropriate amount of energy to deliver. While left atrial wall-thickness is known to exhibit inter- and intra-patient variation, this is not taken into account in the current clinical workflow. Our goal is to develop a tool for presenting patient-specific left atrial thickness information to the clinician in order to assist in the determination of the proper RF energy dose. METHODS: We use an interactive segmentation method with manual correction to segment the left atrial blood pool and heart wall from contrast-enhanced cardiac CT images. We then create a mesh from the segmented blood pool and determine the wall thickness, on a per-vertex basis, orthogonal to the mesh surface. The thickness measurement is visualized by assigning colors to the vertices of the blood pool mesh. We applied our method to 5 contrast-enhanced cardiac CT images. RESULTS: Left atrial wall-thickness measurements were generally consistent with published thickness ranges. Variations were found to exist between patients, and between regions within each patient. CONCLUSION: It is possible to visually determine areas of thick vs. thin heart wall with high resolution in a patient-specific manner.

Inoue, Jiro; Skanes, Allan C.; White, James A.; Rajchl, Martin; Drangova, Maria

2014-03-01

386

Functional cardiac tissue engineering  

PubMed Central

Heart attack remains the leading cause of death in both men and women worldwide. Stem cell-based therapies, including the use of engineered cardiac tissues, have the potential to treat the massive cell loss and pathological remodeling resulting from heart attack. Specifically, embryonic and induced pluripotent stem cells are a promising source for generation of therapeutically relevant numbers of functional cardiomyocytes and engineering of cardiac tissues in vitro. This review will describe methodologies for successful differentiation of pluripotent stem cells towards the cardiovascular cell lineages as they pertain to the field of cardiac tissue engineering. The emphasis will be placed on comparing the functional maturation in engineered cardiac tissues and developing heart and on methods to quantify cardiac electrical and mechanical function at different spatial scales. PMID:22397609

Liau, Brian; Zhang, Donghui; Bursac, Nenad

2013-01-01

387

Dissection of the left main coronary artery after blunt thoracic trauma: Case report and literature review.  

PubMed

Blunt chest trauma is commonly encountered by surgeons and is rarely associated with cardiac injuries. The incidence of cardiac injury is rare but can be rapidly fatal, requiring prompt recognition and treatment. We review the case of a 37 year-old male who was involved in a head-on motor vehicle collision at highway speed and was found to have an isolated left main coronary artery dissection. We then review the supporting literature for evaluation of blunt cardiac injuries and the treatment options for traumatic coronary dissection. PMID:20649988

James, Mollie M; Verhofste, Marnix; Franklin, Cass; Beilman, Greg; Goldman, Charles

2010-01-01

388

Increase in cardiac contractility during puberty.  

PubMed

Pubertal growth of heart was analyzed. Growth rates of "diastolic variables" of heart size were compared with that of 'systolic', and both with growth intensities of some body structures and functions that are related to cardiac growth. Longitudinal echocardiographic, ergometric and anthropometric measurements were performed in 84 healthy boys, aged 11.5 years at the beginning and 14.5 at the end of study. Diastolic thickness of left ventricular walls increased by a mean rate of 15% and systolic by 36% (p < 0.001). As a result, percent systolic wall thickening increased from 20% to 41% during the 3 years (p < 0.001). Other measures of cardiac contractility increased in the same manner. Increase in measures of cardiac preload and afterload corresponds to the increase in heart "diastolic" and "systolic" variables, respectively. The study gave evidences for an increase in cardiac contractility during puberty. Coexistence of two simultaneous growth models for pubertal heart: diastolic and systolic, is suggested. PMID:12974163

Milicevi?, Goran; Naranci?, Nina Smolej; Steiner, Robert; Rudan, Pavao

2003-06-01

389

[The implantable cardiac defibrillator: indications and complications].  

PubMed

The implantation of an implantable cardiac defibrillator (ICD) is indicated as a secondary prevention measure for sudden cardiac death in patients surviving a life-threatening ventricular arrhythmia that had no reversible or treatable cause. An ICD is indicated as a primary prevention measure for sudden cardiac death in patients with a left-ventricular ejection fraction (LVEF) ? 35%. A biventricular ICD is indicated in patients with heart failure class ? II according to the New York Heart Association classification, a widened QRS complex and an LVEF ? 35%. Guidelines do not differentiate between men and women or according to age, but there is no evidence in the literature for decreased mortality from applying ICD therapy in women and in patients older than 70-75 years. This is relevant in discussions over the cost-effectiveness of the treatment. Sudden cardiac death occurs most frequently in patients with an LVEF ? 35%; the effect of ICDs as a primary prevention measure in this patient group has, however, never been investigated. The most important complications following ICD implantation are inappropriate ICD shocks and lead dysfunction. Automated home-monitoring enables early detection of technical defects. PMID:24252404

Simmers, T A Tim; Bracke, Frank A L E

2013-01-01

390

Cardiac I-1c Overexpression With Reengineered AAV Improves Cardiac Function in Swine Ischemic Heart Failure.  

PubMed

Cardiac gene therapy has emerged as a promising option to treat advanced heart failure (HF). Advances in molecular biology and gene targeting approaches are offering further novel options for genetic manipulation of the cardiovascular system. The aim of this study was to improve cardiac function in chronic HF by overexpressing constitutively active inhibitor-1 (I-1c) using a novel cardiotropic vector generated by capsid reengineering of adeno-associated virus (BNP116). One month after a large anterior myocardial infarction, 20 Yorkshire pigs randomly received intracoronary injection of either high-dose BNP116.I-1c (1.0?×?10(13) vector genomes (vg), n = 7), low-dose BNP116.I-1c (3.0?×?10(12) vg, n = 7), or saline (n = 6). Compared to baseline, mean left ventricular ejection fraction increased by 5.7% in the high-dose group, and by 5.2% in the low-dose group, whereas it decreased by 7% in the saline group. Additionally, preload-recruitable stroke work obtained from pressure-volume analysis demonstrated significantly higher cardiac performance in the high-dose group. Likewise, other hemodynamic parameters, including stroke volume and contractility index indicated improved cardiac function after the I-1c gene transfer. Furthermore, BNP116 showed a favorable gene expression pattern for targeting the heart. In summary, I-1c overexpression using BNP116 improves cardiac function in a clinically relevant model of ischemic HF. PMID:25023328

Ishikawa, Kiyotake; Fish, Kenneth M; Tilemann, Lisa; Rapti, Kleopatra; Aguero, Jaume; Santos-Gallego, Carlos G; Lee, Ahyoung; Karakikes, Ioannis; Xie, Chaoqin; Akar, Fadi G; Shimada, Yuichi J; Gwathmey, Judith K; Asokan, Aravind; McPhee, Scott; Samulski, Jade; Samulski, Richard Jude; Sigg, Daniel C; Weber, Thomas; Kranias, Evangelia G; Hajjar, Roger J

2014-12-01

391

Strategies to improve cardiac resynchronization therapy.  

PubMed

Cardiac resynchronization therapy (CRT) emerged 2 decades ago as a useful form of device therapy for heart failure associated with abnormal ventricular conduction, indicated by a wide QRS complex. In this Review, we present insights into how to achieve the greatest benefits with this pacemaker therapy. Outcomes from CRT can be improved by appropriate patient selection, careful positioning of right and left ventricular pacing electrodes, and optimal timing of electrode stimulation. Left bundle branch block (LBBB), which can be detected on an electrocardiogram, is the predominant substrate for CRT, and patients with this conduction abnormality yield the most benefit. However, other features, such as QRS morphology, mechanical dyssynchrony, myocardial scarring, and the aetiology of heart failure, might also determine the benefit of CRT. No single left ventricular pacing site suits all patients, but a late-activated site, during either the intrinsic LBBB rhythm or right ventricular pacing, should be selected. Positioning the lead inside a scarred region substantially impairs outcomes. Optimization of stimulation intervals improves cardiac pump function in the short term, but CRT procedures must become easier and more reliable, perhaps with the use of electrocardiographic measures, to improve long-term outcomes. PMID:24839977

Vernooy, Kevin; van Deursen, Caroline J M; Strik, Marc; Prinzen, Frits W

2014-08-01

392

Cardiac involvement in chronic progressive external ophthalmoplegia.  

PubMed

Myocardial involvement has not been extensively investigated in mitochondrial myopathies. The aim of the study was to assess the myocardial morpho-functional changes in patients with chronic progressive external ophthalmoplegia (PEO). Twenty patients with PEO and 20 controls underwent standard echocardiography with tissue Doppler imaging (TDI) and integrated backscatter (IBS) analyses. These techniques are capable of providing non-invasively the early, subtle structural and functional changes of the myocardium. TDI myocardial systolic (Sm) and early (Em) and late (Am) diastolic velocities of left ventricular walls were determined. The systo-diastolic variation of IBS was also determined. Patients with PEO exhibited lower Sm, lower Em, and higher Am, and a reduced Em/Am ratio than controls (p<0.001 for all) at interventricular septum and lateral wall levels. In PEO patients, septal and posterior wall cyclic variations of IBS were significantly lower than those in controls (p<0.001). Patients with PEO showed myocardial wall remodeling characterized by increased fibrosis and early left ventricular systo-diastolic function abnormalities. Although cardiac involvement in PEO is generally considered to be limited to the cardiac conduction system, left ventricular dysfunction may be present and should receive more attention in the management of these patients. PMID:25139213

Galetta, Fabio; Franzoni, Ferdinando; Mancuso, Michelangelo; Orsucci, Daniele; Tocchini, Leonardo; Papi, Riccardo; Speziale, Giuseppe; Gaudio, Carlo; Siciliano, Gabriele; Santoro, Gino

2014-10-15

393

Feasibility of creating estimates of left ventricular flow-volume dynamics using echocardiography  

PubMed Central

Background This study explores the feasibility of non-invasive assessment of left ventricular volume and flow relationship throughout cardiac cycle employing echocardiographic methods. Methods Nine healthy individuals and 3 patients with severe left-sided valvular abnormalities were subject to resting echocardiography with automated endocardial border detection allowing real-time estimation of left ventricular volume throughout the cardiac cycle. Global and regional (6 different left ventricular segments) estimates of flow-volume loops were subsequently constructed by plotting acquired instantaneous left ventricular 2-D area data (left ventricular volume) vs. their first derivatives (flow). Results Flow-volume loop estimates were obtainable in 75% of all echocardiographic images and displayed in normal individuals some regional morphological variation with more pronounced isovolumic events in the paraseptal segments and significantly delayed maximal systolic flow paraapically. In patients with aortic stenosis, maximal systolic flow occurred at a lower estimated left ventricular systolic volume whereas in mitral stenosis, maximal diastolic flow was observed at a higher estimated left ventricular diastolic volume. Aortic regurgitation caused a complex alteration of the estimated flow-volume loop shape during diastole. Conclusion Non-invasive assessment of left ventricular flow-volume relationship with echocardiography is technically feasible and reveals the existence of regional variation in flow-volume loop morphology. Valvular abnormalities cause a clear and specific alteration of the estimates of the normal systolic or diastolic flow-volume pattern, likely reflecting the underlying pathophysiology. PMID:17074099

Söderqvist, Emil; Cain, Peter; Lind, Britta; Winter, Reidar; Nowak, Jacek; Brodin, Lars-Åke

2006-01-01

394

Operation Everest III (Comex '97): modifications of cardiac function secondary to altitude-induced hypoxia. An echocardiographic and Doppler study.  

PubMed

During Operation Everest III (Comex '97), to assess the consequences of altitude-induced hypoxia, eight volunteers were decompressed in a hypobaric chamber, with a decompression profile simulating the climb of Mount Everest. Cardiac function was assessed using a combination of M-mode and two-dimensional echocardiography, with continuous and pulsed Doppler at 5,000, 7,000, and 8,000 m as well as 2 d after return to sea level (RSL). On simulated ascent to altitude, aortic and left atrial diameters, left ventricular (LV) diameters, and right ventricular (RV) end-systolic diameter fell regularly. Heart rate (HR) increased at all altitudes accompanied by a decrease in stroke volume; in total, cardiac output (Q) remained unchanged. LV filling was assessed on transmitral and pulmonary venous flow profiles. Mitral peak E velocity decreased, peak A velocity increased, and E/A ratio decreased. Pulmonary venous flow velocities showed a decreased peak D velocity, a decreased peak S velocity, and a reduction of the D/S ratio. Systolic pulmonary arterial pressure (Ppa) showed a progressive and constant increase, as seen on the elevation of the right ventricular/right atrial (RV/RA) gradient pressure from 19.0 +/- 2.4 mm Hg at sea level up to 40.1 +/- 3.3 mm Hg at 8,000 m (p < 0.05), and remained elevated 2 d after recompression to sea level (SL) (not significant). In conclusion, this study confirmed the elevation of pulmonary pressures and the preservation of LV contractility secondary to altitude-induced hypoxia. It demonstrated a modification of the LV filling pattern, with a decreased early filling and a greater contribution of the atrial contraction, without elevation of LV end-diastolic pressure. PMID:10619830

Boussuges, A; Molenat, F; Burnet, H; Cauchy, E; Gardette, B; Sainty, J M; Jammes, Y; Richalet, J P

2000-01-01

395

Long-term wheel running compromises diaphragm function but improves cardiac and plantarflexor function in the mdx mouse  

PubMed Central

Dystrophin-deficient muscles suffer from free radical injury, mitochondrial dysfunction, apoptosis, and inflammation, among other pathologies that contribute to muscle fiber injury and loss, leading to wheelchair confinement and death in the patient. For some time, it has been appreciated that endurance training has the potential to counter many of these contributing factors. Correspondingly, numerous investigations have shown improvements in limb muscle function following endurance training in mdx mice. However, the effect of long-term volitional wheel running on diaphragm and cardiac function is largely unknown. Our purpose was to determine the extent to which long-term endurance exercise affected dystrophic limb, diaphragm, and cardiac function. Diaphragm specific tension was reduced by 60% (P < 0.05) in mice that performed 1 yr of volitional wheel running compared with sedentary mdx mice. Dorsiflexor mass (extensor digitorum longus and tibialis anterior) and function (extensor digitorum longus) were not altered by endurance training. In mice that performed 1 yr of volitional wheel running, plantarflexor mass (soleus and gastrocnemius) was increased and soleus tetanic force was increased 36%, while specific tension was similar in wheel-running and sedentary groups. Cardiac mass was increased 15%, left ventricle chamber size was increased 20% (diastole) and 18% (systole), and stroke volume was increased twofold in wheel-running compared with sedentary mdx mice. These data suggest that the dystrophic heart may undergo positive exercise-induced remodeling and that limb muscle function is largely unaffected. Most importantly, however, as the diaphragm most closely recapitulates the human disease, these data raise the possibility of exercise-mediated injury in dystrophic skeletal muscle. PMID:23823150

Acosta, Pedro; Sleeper, Meg M.; Barton, Elisabeth R.; Sweeney, H. Lee

2013-01-01

396

Long-term wheel running compromises diaphragm function but improves cardiac and plantarflexor function in the mdx mouse.  

PubMed

Dystrophin-deficient muscles suffer from free radical injury, mitochondrial dysfunction, apoptosis, and inflammation, among other pathologies that contribute to muscle fiber injury and loss, leading to wheelchair confinement and death in the patient. For some time, it has been appreciated that endurance training has the potential to counter many of these contributing factors. Correspondingly, numerous investigations have shown improvements in limb muscle function following endurance training in mdx mice. However, the effect of long-term volitional wheel running on diaphragm and cardiac function is largely unknown. Our purpose was to determine the extent to which long-term endurance exercise affected dystrophic limb, diaphragm, and cardiac function. Diaphragm specific tension was reduced by 60% (P < 0.05) in mice that performed 1 yr of volitional wheel running compared with sedentary mdx mice. Dorsiflexor mass (extensor digitorum longus and tibialis anterior) and function (extensor digitorum longus) were not altered by endurance training. In mice that performed 1 yr of volitional wheel running, plantarflexor mass (soleus and gastrocnemius) was increased and soleus tetanic force was increased 36%, while specific tension was similar in wheel-running and sedentary groups. Cardiac mass was increased 15%, left ventricle chamber size was increased 20% (diastole) and 18% (systole), and stroke volume was increased twofold in wheel-running compared with sedentary mdx mice. These data suggest that the dystrophic heart may undergo positive exercise-induced remodeling and that limb muscle function is largely unaffected. Most importantly, however, as the diaphragm most closely recapitulates the human disease, these data raise the possibility of exercise-mediated injury in dystrophic skeletal muscle. PMID:23823150

Selsby, Joshua T; Acosta, Pedro; Sleeper, Meg M; Barton, Elisabeth R; Sweeney, H Lee

2013-09-01

397

Cyclically controlled welding purge chamber  

NASA Technical Reports Server (NTRS)

An arrangement for butt-welding cylindrical sections of large, thin-wall tanks includes a rotatable mandrel with side-by-side sets of radial position adjusters. Each set of adjusters bears on one of the tank sections adjacent the seam, to prevent the sections from sagging out-of-round. The mandrel rotates relative to the welder, so that a continuous seam is formed. A purge chamber is fixed in position behind the seam at the weld head, and is flushed with inert gas. The purge chamber includes a two-sided structure which is contiguous with the cylindrical sections and a circumferential vane to form an open-ended tube-like structure, through which the radial position adjusters pass as the mandrel and cylindrical workpiece sections rotate. The tube-like structure is formed into a chamber by a plurality of movable gates which are controlled to maintain a seal while allowing adjusters to progress through the purge chamber.

Gallagher, Robert L. (Inventor)

1996-01-01

398

Gross anatomy of the cardiac blood vessels in the North American beaver (Castor canadensis).  

PubMed

The cardiac arteries and veins are described in the North American beaver (Castor canadensis) following the injection of the vessels of 15 hearts with either latex, vinyl plastic or barium sulfate. The left coronary artery gives off the typical circumflex and paraconal interventricular branches which supply the left atrium and ventricle and part of the right ventricle and interventricular septum. The right coronary artery vascularizes the right atrium and ventricule and by means of its subsinuosal interventricular branch, part of the left ventricle and interventricular septum. The paraconal interventricular branch of the left coronary artery lies within the myocardium and is not visible on the surface of the heart. There are no intercoronary anastomoses between the right and left vessels. The major cardiac veins open into the terminal end of the left cranial vena cava. Unlike the arteries, there are venous anastomoses interconnecting the great cardiac vein and the middle cardiac vein. It is concluded that the cardiac blood vessels in Castor canadensis are typically mammalian and resemble those of both land and aquatic mammals. PMID:7305001

Bisaillon, A

1981-01-01

399

Implantation of left ventricular assist device complicated by undiagnosed thrombophilia.  

PubMed

A patient with dilated cardiomyopathy and no history of thromboembolic events received a surgically implanted axial-flow left ventricular assist device. After implantation, transesophageal echocardiography revealed a giant thrombus on the lateral and anterior aspects of the left ventricle. The inflow cannula inserted through the apex of the left ventricle was not obstructed, and the device generated satisfactory blood flow. Laboratory screening for thrombophilia showed protein S deficiency, heterozygous factor V Leiden mutation, and heterozygous MTHFR C667T mutation. During the entire duration of circulatory support, no significant suction events were detected, and the patient was listed for heart transplantation. Ventricular assist device implantation can unmask previously undiagnosed thrombophilia; therefore, it should be necessary to identify thrombophilic patients before cardiac support implantation. PMID:23109751

Szarszoi, Ondrej; Maly, Jiri; Turek, Daniel; Urban, Marian; Skalsky, Ivo; Riha, Hynek; Maluskova, Jana; Pirk, Jan; Netuka, Ivan

2012-01-01

400

Giant lateral left ventricular wall aneurysm sparing the submitral apparatus  

PubMed Central

Left ventricular aneurysms are a frequent and serious complication following acute transmural myocardial infarction and are most commonly located at the ventricular apex. The majority of these patients presents with severe mitral insufficiency, congestive heart failure, systemic embolism and sudden cardiac death. Giant aneurysms occurring in a submitral position between anterior and posterior papillary muscles on the lateral ventricular wall constitute a minor entity and those leaving the mitral apparatus intact are extremely rare. Herein, we report the case of a 57 y/o Caucasian male patient with a past medical history of coronary artery disease and myocardial infarction with a giant left ventricular aneurysm measuring 15x10x8 cm in diameter. Despite the size of the aneurysm and its close topographical relation to the posterior mitral annulus the mitral apparatus was intact with a competent valve and normal left atrial size. He underwent successful surgical ventricular restoration. PMID:24172071

2013-01-01

401

Differential diagnosis between left ventricular hypertrophy and cardiomyopathy in childhood.  

PubMed

The sensitivity and specificity of the electrocardiogram for the diagnosis of left ventricular hypertrophy of different etiologies are described. The sensitivity of the electrocardiogram for detecting left ventricular pressure overload is substantially lower (<35%) than the sensitivity for detecting evidence of a cardiomyopathy (55% to around 87%). Attention is drawn to the finding that in many differing etiologies of left ventricular hypertrophy ST-T-wave changes commonly referred to as "strain"-pattern are a harbinger of an increased risk of malignant cardiac arrhythmias and sudden death. In the most common pediatric cause of sudden death, hypertrophic cardiomyopathy, a described ECG risk score, which scores both voltage and repolarization abnormalities, is the most powerful predictor hitherto described for predicting the risk of sudden death in this diagnosis. A point score over 5 points gives a relative risk for sudden death of 24.3 with a sensitivity of 96% and a specificity of 78% in childhood. PMID:25060129

Östman-Smith, Ingegerd

2014-01-01

402