Texas Heart Institute journal
-
Review Case Reports
Two cases of Bezold-Jarisch reflex induced by intra-arterial nitroglycerin in critical left main coronary artery stenosis.
The Bezold-Jarisch reflex, a well-described phenomenon, occurs upon the stimulation of intracardiac mechanoreceptors and is mediated by vagal afferent nerve fibers. Several factors can sensitize the cardiovascular system to develop this reflex, including acute myocardial ischemia, natriuretic peptides, and, rarely, nitroglycerin administration in the setting of acute myocardial infarction. The development of the Bezold-Jarisch reflex in the presence of severe coronary artery stenosis, specifically left main coronary artery stenosis, has not been described. ⋯ Coronary angiography revealed critical (>90%) left main coronary artery stenosis in both patients. Critical left main coronary artery stenosis might sensitize mechanoreceptors or vagal afferents to the development of the Bezold-Jarisch reflex after intra-arterial nitroglycerin use; however, the mechanism of this possible relationship is unclear. In addition to discussing our patients' cases, we review the medical literature relevant to the Bezold-Jarisch reflex.
-
Sudden cardiac death in athletes is a recurrent phenomenon at sporting events and during training. Recent studies have associated sudden cardiac death with such cardiovascular conditions as coronary artery anomalies, cardiomyopathies, and electrocardiographic abnormalities, most of which are screenable with modern imaging techniques. We recently inaugurated the Center for Coronary Artery Anomalies at the Texas Heart Institute, which is dedicated to preventing sudden cardiac death in the young and investigating coronary artery anomalies. ⋯ Eventually, we hope to use our findings to develop a more efficient method of preventing sudden cardiac death in athletes. We believe that these studies will help quantify sudden cardiac death risk factors and the relevance of associated physical activities--crucial information in evaluating the feasibility and affordability of cardiovascular magnetic resonance-based screening. We discuss the rationale for and methods of this long-term endeavor, in advance of reporting the results.
-
Is rheumatic mitral valve repair still a feasible alternative?: indications, technique, and results.
Rheumatic heart disease is still a major cause of mitral valve dysfunction in developing countries. We present our early results of rheumatic mitral valve repair. From August 2009 through July 2011, 60 patients (24 male and 36 female) with rheumatic disease underwent mitral repair. ⋯ Left ventricular end-diastolic diameter and left atrial diameter significantly decreased postoperatively (P=0.006 and P=0.001, respectively). The mean gradient over the mitral valve decreased significantly from 11 ± 5.9 mmHg to 3.5 ± 1.8 mmHg (P=0.001). Because current techniques of mitral repair can effectively correct valve dysfunction in most patients with rheumatic disease, the number of repair procedures should be increased in developing countries to prevent complications of mechanical valve placement.
-
Case Reports
Surgical approach to aortic valve replacement after previous bilateral internal thoracic artery grafting.
The authors present a manubrium-sparing sternotomy technique for aortic valve replacement in patients who have undergone previous myocardial revascularization with both internal thoracic arteries. They have found that preoperative 64-multislice computed tomographic imaging facilitates surgical planning by delineating the course of patent grafts and, in particular, the relationship between the sternum and the right internal thoracic artery graft. A manubrium-sparing sternotomy can in such instances avoid injury to the right internal thoracic artery graft during both resternotomy and adhesion dissection, thus reducing surgical risk and operative time.