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Cardiac Anatomy (cardiac + anatomy)
Selected AbstractsVolume Reduction Surgery for End-Stage Ischemic Heart DiseaseECHOCARDIOGRAPHY, Issue 7 2002Takahiro Shiota M.D. The Dor procedure, or infarction excision surgery, was first used in 1984. It is a surgical treatment option for patients with end-stage ischemic heart failure. In a recently published multicenter study that included a total of 439 patients, average ejection fraction increased from 29 ± 10% to 39 ± 12% after surgery. In our experience, the overall survival rate 18 months after surgery is 89%, and the preoperative mortality rate is 6.6%. These results are similar to the previous reports from Dor,s group, which confirmed the certain value of the surgery. Echocardiography, including intraoperative transesophageal echocardiography, plays an important role in clarifying cardiac anatomies, absolute left ventricular (LV) volumes, ejection fraction, and mitral regurgitation in patients with ischemic heart failure undergoing this surgery. With the development of ultrasound and computer technology, three-dimensional echocardiography may be preferred when evaluating the surgical results, including determination of absolute LV volumes. Communication between experienced cardiac surgeons and echocardiographers in the operating room is essential for successful outcomes and reliable evaluation of the surgery. [source] A Comparison of Echocardiographic Techniques in Determination of Arterial Elasticity in the Pediatric PopulationECHOCARDIOGRAPHY, Issue 5 2009Michael Fahey M.D. Background: Many methods are used to measure arterial elasticity in children using echocardiography. There is no data to support the equivalence of the different techniques. The goal of this study was to evaluate the reproducibility of several techniques used to measure arterial elasticity using echocardiography. Methods: Aortic distension in two different sites (arterial distension) through the cardiac cycle was measured by (four) two-dimensional (2D) and M-mode echocardiographic techniques in 20 children without significant structural heart disease. These measurements combined with noninvasive blood pressure measurements were used to calculate arterial elastic indices. Arterial elasticity was expressed in terms of distensibility and stiffness. Data were collected by two sonographers and interpreted by two reviewers. Paired Student's t-test and Pitman's test for equality of variance for correlated observations were used to detect differences between different sonographers, different reviewers, and different techniques. Results: No significant difference in the measured elasticity between sonographers or reviewers was observed. There was a somewhat increased variance in two of the four techniques evaluated. There was no significant difference in elasticity measured using different techniques to evaluate the same arterial site, although a significantly decreased elasticity was noted from measurements taken in the proximal ascending aorta as compared with the distal ascending aorta. Conclusions: Many echocardiographic techniques produce reproducible measurements of arterial elasticity. There may be intrinsic differences in arterial elasticity between different segments of the ascending aorta, which have not been previously described in children with normal cardiac anatomy. Comparisons of data from separate studies must take these differences into account. [source] Orthotopic Cardiac Transplantation: Comparison of Outcome Using Biatrial, Bicaval, and Total TechniquesJOURNAL OF CARDIAC SURGERY, Issue 1 2005Jeffrey A. Morgan M.D. More recently, however, bicaval and total techniques have been devised in an attempt to improve cardiac anatomy, physiology, and postoperative outcome. A bicaval approach preserves the donor atria and combines the standard left atrial anastomosis with a separate bicaval anastomosis. Total orthotopic heart transplantation involves complete excision of the recipient atria with separate bicaval end-to-end anastomoses, as well as pulmonary venous anastomoses. The aim of this study was to conduct a literature review of studies that compared the three surgical techniques (biatrial, bicaval, and total) for performing orthotopic cardiac transplantation. Numerous outcome variables were evaluated, and included post-transplant survival, atrial dimensions, atrioventricular valvular insufficiency, arrhythmias, pacing requirements, vasopressor requirements, and hospital stay. Methods: We conducted a Medline (Pubmed) search using the terms "biatrial and cardiac transplantation,""bicaval and cardiac transplantation," and "total technique and cardiac transplantation," which yielded 192 entries: 39 of these were studies that compared surgical techniques and were included in the review. Results: There was overwhelming evidence that the bicaval technique provided anatomic and functional advantages, with improvements in post-transplant survival, atrial geometry, and hemodynamics, as well as decreased valvular insufficiency, arrhythmias, pacing requirements, vasopressor requirements, and hospital stay. Conclusions: The bicaval technique was superior to both biatrial and total techniques for numerous outcome variables. To further elucidate this issue, a prospective randomized trial comparing the three techniques, with long-term follow-up, is warranted. [source] Techniques and Applications of Transcatheter Embolization Procedures in Pediatric CardiologyJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2003JAMES Y. SIM M.D. Transcatheter embolization of congenital or acquired superfluous vascular structure has become routine procedures performed by interventional pediatric cardiologists. Embolization procedure is often part of a collaborative effort with cardiac surgeons to palliate complex congenital heart defect, such as in embolizing aortopulmonary collateral arteries in patient with single ventricle physiology. In other cases, the procedure is the definitive treatment as in embolizing coronary artery fistula. Pediatric cardiologists performing embolization procedures should be familiar with available technologies as well as understand the underlying cardiac anatomy and pathophysiology. This article provides a comprehensive review of presently available embolization agents and technologies. Some of the technologies are used only by interventional radiologists but may be useful to pediatric cardiologists. Specific clinical applications in pediatric cardiology are also discussed with summary of current literature. With continue advancement in transcatheter technology and operator expertise, all unwanted vascular communication should be amenable to transcatheter embolization. (J Interven Cardiol 2003;16:425,448) [source] Magnetic resonance imaging for ischemic heart diseaseJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2007Hajime Sakuma MD Abstract Cardiac MRI has long been recognized as an accurate and reliable means of evaluating cardiac anatomy and ventricular function. Considerable progress has been made in the field of cardiac MRI, and cardiac MRI can provide accurate evaluation of myocardial ischemia and infarction (MI). Late gadolinium (Gd)-enhanced MRI can clearly delineate subendocardial infarction, and the assessment of transmural extent of infarction on late enhanced MRI has been shown to be useful in predicting functional recovery of dysfunctional myocardium in patients after MI. Stress first-pass contrast-enhanced (CE) myocardial perfusion MRI can be used to detect subendocardial ischemia, and recent studies have demonstrated the high diagnostic accuracy of stress myocardial perfusion MRI for detecting significant coronary artery disease (CAD). Free-breathing, whole-heart coronary MR angiography (MRA) was recently introduced as a method that can provide visualization of all three major coronary arteries within a single three-dimensional (3D) acquisition. With further improvements in MRI techniques and the establishment of a standardized study protocol, cardiac MRI will play a pivotal role in managing patients with ischemic heart disease. J. Magn. Reson. Imaging 2007;26:3,13. © 2007 Wiley-Liss, Inc. [source] The heart of the South American rattlesnake, Crotalus durissusJOURNAL OF MORPHOLOGY, Issue 9 2010Bjarke Jensen Abstract Most anatomical and physiological studies of the sauropsid heart have focused on species with extraordinary physiologies, and detailed anatomical descriptions of hearts from sauropsids with more common physiologies are therefore warranted. Here, we present a comprehensive study of the cardiac anatomy of the South American rattlesnake (Crotalus durissus). The cardiovascular physiology of this species has been investigated in a number of studies, whereas only a few cursory studies exist on the cardiac anatomy of viperid snakes. The heart of C. durissus is typically squamate in many regards. Both atria are thin-walled sacs, and the right atrium is the most voluminous. The single ventricle contains three major septa; the vertical septum, the muscular ridge (MR), and the bulbuslamelle. These partially divide the ventricle into three chambers; the systemic and left-sided cavum arteriosum (CA), the pulmonary and right-sided cavum pulmonale, and the medial cavum venosum (CV). The MR is the most developed septum, and several additional and minor septa are found within the CA and CV. An extraordinary thin cortical layer encloses the ventricle, and it is irrigated by a remarkably rich arborization of coronary arteries. Previous studies show high degrees of blood flow separation in the Crotalus heart, and this can only be explained by the coordinated actions of the septa and the prominent atrioventricular valves. J. Morphol. 271:1066-1077, 2010. © 2010 Wiley-Liss, Inc. [source] A Shock Lead Intentionally Placed in the Left VentriclePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2009KARIN KRAAIER M.D. The implantable cardioverter defibrillator is effective in reducing sudden cardiac death in high-risk patients. The implantation procedure is usually simple; however, in those patients who have congenital heart disease (CHD) placement of leads can be a challenge. In this report we present a patient with CHD where due to the complex cardiac anatomy it was decided to place the shock lead in the left ventricle. [source] Low Energy Biphasic Waveform Cardioversion of Atrial Arrhythmias in Pediatric Patients and Young AdultsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2006LEONARDO LIBERMAN M.D. Background: Low-dose biphasic waveform cardioversion has been used for the termination of atrial arrhythmias in adult patients. The energy required for termination of atrial arrhythmias in pediatric patients is not known. The objective of this study is to determine the minimum energy required for successful external cardioversion of atrial arrhythmias in pediatric patients using biphasic waveform current. Methods: Prospective study of all patients less than 24 years of age with and without congenital heart disease undergoing synchronized cardioversion for atrial arrhythmias. Patients were assigned to receive an initial biphasic energy shock of 0.2,0.5 J/kg and if unsuccessful in terminating the arrhythmia, subsequent sequential shocks of 1 and 2 J/kg would be administered until cardioversion was achieved. The end point of the cardioversion protocol was successful cardioversion or delivery of three shocks. Results: Between June 2005 and June 2006, 16 patients underwent biphasic cardioversion for atrial flutter or fibrillation. The mean age was 14.7 ± 6.4 years (range: 2 weeks to 24 years). The mean weight was 51 ± 21 kg (range: 3.8,82 kg). Seven patients had normal cardiac anatomy, three had a single ventricle (Fontan), two had a Senning operation; the remaining four patients had varied forms of congenital heart disease. The median length of time that the patients were in tachycardia was 12 hours (range: 5 minutes to 2 months). Using either transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE), no thrombi were identified in any patient. All patients were successfully cardioverted with biphasic waveform energy. The successful energy shock was 0.35 ± 0.19 J/kg (range: 0.2,0.9 J/kg). All but one patient were successfully cardioverted with less than 0.5 J/kg. The transthoracic impedance range was between 41 and 144 ,; one patient had an impedance of 506 , (2-week-old infant with a weight of 3.8 kg). The mean current delivered was 5.4 ± 2.2 A (range: 1,11 A). Conclusion: Low-dose energy using biphasic waveform shocks can be used for successful termination of atrial arrhythmias in pediatric patients with and without congenital heart disease. [source] Normal and abnormal fetal cardiac anatomyPRENATAL DIAGNOSIS, Issue 13 2004Andrew C. Cook Abstract The heart is often perceived as a difficult organ to understand by ultrasound during fetal life. This is undoubtedly reflected in the low detection rate of cardiac abnormalities as compared to those of most other organ systems in the fetus. In this article we start by updating classical concepts of cardiac embryology, many of which were previously difficult to understand since they were overly simplistic or purely observational. We then lead on to the structure and growth of the fully formed fetal heart where we review the anatomy and ultrasound appearances in detail and provide comparisons with major abnormalities. We emphasise the fact that a solid understanding of cardiac anatomy can enable those involved in fetal medicine to make full use of the views of the heart that are obtained by ultrasound and which are often only transient. Copyright © 2004 John Wiley & Sons, Ltd. [source] Introduction to the special issue on cardiac anatomyCLINICAL ANATOMY, Issue 1 2009Robert H. Anderson No abstract is available for this article. [source] An antidiabetic thiazolidinedione induces eccentric cardiac hypertrophy by cardiac volume overload in ratsCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 1-2 2004Kenji Arakawa Summary 1.,To assess the involvement of volume overload in the development of cardiac hypertrophy during treatment with an antidiabetic thiazolidinedione, changes in cardiac anatomy and parameters of cardiac volume overload were evaluated in female Sprague-Dawley rats treated with the thiazolidinedione derivative T-174. 2.,Two week administration of T-174 (13 and 114 mg/kg per day) increased absolute and relative heart weights by 11,24%, demonstrating the development of cardiac hypertrophy. There was no evidence of oedema in hearts from treated rats. 3.,Both plasma and blood volumes were increased in T-174-treated rats without any changes in systolic blood pressure and heart rate, whereas haematocrit was decreased. In accordance with the existence of volume overload, both left ventricular end-diastolic pressure and right atrial pressure were increased. Morphometric analysis of hearts revealed that T-174 induced eccentric heart hypertrophy, as characterized by a small increase in wall thickness and a large increase in the chamber volume, which is characteristic of volume overload. Volume overload is suggested as the possible trigger mechanism because blood volume expansion preceded cardiac hypertrophy and there was a high correlation between heart weight and blood volume. 4.,T-174-treated streptozotocin-induced diabetic rats also exhibited blood volume expansion and cardiac hypertrophy. 5.,These findings suggest that cardiac volume overload is induced by plasma volume expansion and contributes to the development of eccentric cardiac hypertrophy during treatment with antidiabetic thiazolidinediones. Although thiazolidinediones are insulin-sensitizing agents, these cardiac effects are likely to be mediated independently of insulin. [source] | |||||||||||||