The phenomenon of multiple myocardial contractions during each single cardiac cycle, triggered by a single sinus node impulse, is the most intriguing echocardiographical topic among detectible modalities of irregular kinetics of interventricular septum. Tissue Doppler imaging based methods gave proofs of active contractions in cases presented herein. Broad spectrum of this phenomenon, which can...

Myocardial infarction after coronary artery bypass graft (CABG) surgery has been described clinically in up to 30% of patients but there is little morphologic information about the character and pathogenesis of this myocardial injury. We studied myocardium in the distribution of bypassed and nonbypassed coronary arteries for the presence of contraction band necrosis as compared to coagulation n...

Regional myocardial motion analysis is used in clinical routine to inspect cardiac contraction in myocardial diseases such as infarction or hypertrophy. Physicians/radiologists can recognize abnormal cardiac motion because they have knowledge about normal heart contraction. This paper explores the potential of Independent Component Analysis (ICA) to extract local myocardial contractility patter...

The effects of exogenous and endogenous. NO on myocardial functions such as contraction, relaxation and heart rate have recently gained considerable scientific interest. .NO stimulates myocardial soluble guanylate cyclase to produce cGMP, which activates two major target proteins. A small increase in cGMP levels predominantly inhibits phosphodiesterase III, while high cGMP levels activate cGMP-...

Introduction Myocardial contraction is a cyclic event. Contraction delay can be described in terms of mechanical dispersion or phase delay of velocity, displacement and local deformation (strain) of segments in apical views of the left ventricle. Our hypothesis was that an increase in the standard deviation of phase would be seen as a consequence of myocardial scar and that this effect could be...

BACKGROUND The index of myocardial performance has prognostic power in patients with cardiomyopathy and following myocardial infarction. As the index of myocardial performance has been shown to be preload and afterload dependent, the effect of altering contractility on IMP and its components with left ventricular dysfunction has been incompletely delineated. METHODS Chronic left ventricular d...

conclusions the results suggest the important role of the antioxidant system potentiation in the prevention of myocardial damage. results cell degenerative changes, pyknotic nuclei, contraction bands, edema, and loosening of collagen in between muscle fibers were observed during ischemia-reperfusion. myocardial architecture and cellular morphology were recovered in co-administration groups, esp...

Incomplete recovery of myocardial contraction after reperfusion following brief ischemia is called the "stunning phenomenon" in an animal experiment. A hydrophilic 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor (statin) does not affect this phenomenon, but lipophilic statins further reduce the contraction during reperfusion. The effects of novel hydrophilic rosuvastatin and...

Received July 15, 2008. Accepted for publication January 14, 2009. Introduction and objectives. Left ventricular filling begins in the ventricular isovolumic relaxation phase. According to the Torrent-Guasp myocardial band theory, this phase results from the contraction of the final portion of the myocardial band: the ascending segment of the apical loop. The objectives were to study the myocar...

There is increasing evidence that cocaine can have serious adverse effects on the heart. Angina, myocardial infarction, coronary artery spasm, arrhythmia, and sudden death have been reported in association with its use. There have been only two reports of actual myocardial pathology. In an attempt to clarify the pathophysiology of cocaine-associated cardiotoxicity and to search for pathologic c...