BACKGROUND Myocyte apoptosis is seen in ischemic heart disease, but whether it can occur after reversible ischemia or independent of necrosis and replacement fibrosis is unknown. METHODS AND RESULTS Pigs were instrumented with a stenosis of the left anterior descending coronary artery to chronically reduce coronary flow reserve over a period of 3 months. At this time, there was viable dysfunc...

OBJECTIVES The goal of this study was to investigate the effects of ischemia-reperfusion on myocardial ultrastructure in patients with and without hibernating myocardium. BACKGROUND It is generally accepted that chronically dysfunctional, hibernating myocardium may remain nonetheless viable for a long time. It has been postulated that hibernating myocytes may survive, despite being subtended ...

(F-18 FDG) in the fasting state, in contrast to the relative absence of F-18 FDG uptake in normal myocardium with sufficient blood flow in the fasting state. Although many studies have attempted to use F-18 FDG uptake to discriminate ischemic but viable myocardium from scarred myocardium, little is known clinically about the correlation between blood flow and F-18 FDG uptake in ischemic myocard...

BACKGROUND Although the recent surgical treatment of ischemic heart failure substudy reported that revascularization of viable myocardium did not improve survival, these results were limited by the viability imaging technique used and the lack of inducible ischemia information. We examined the relative impact of stress-rest rubidium-82/F-18 fluorodeoxyglucose positron emission tomography identi...

Skeletal muscle derived stem cells (MDSCs) transplanted into injured myocardium can differentiate into fast skeletal muscle specific myosin heavy chain (sk-fMHC) and cardiac specific troponin-I (cTn-I) positive cells sustaining recipient myocardial function. We have recently found that MDSCs differentiate into a cardiomyocyte phenotype within a three-dimensional gel bioreactor. It is generally ...

BACKGROUND This study proposes 2 new echocardiographic indices with potential application in acute coronary artery occlusion to differentiate between viable and necrotic myocardium and to identify reperfusion. We investigated whether the ratio between systolic lengthening and combined late and postsystolic shortening (L-S ratio) could identify viable myocardium and whether systolic myocardial c...

BACKGROUND In congestive heart failure (idiopathic dilated cardiomyopathy), exercise is accompanied by a smaller-than-normal decrease in end-diastolic left ventricular volume, depressed peak rates of left ventricular pressure rise and fall, and depressed heart-rate-dependent potentiation of contractility (bowditch treppe). We studied contractile function of isolated left ventricular myocardium ...

Background To date, the underlying mechanism responsible for the restoration of the injured myocardium following transplantation of stem cells has not been clearly identified. Three major hypotheses have been previously proposed: cardiac differentiation of transplanted cells (de novo myocardial regeneration), paracrine effect on existing myocardium (myocardial salvage) or recruitment of cardiac...

Late gadolinium enhanced magnetic resonance imaging (MRI) is an established technique for quantification of dense myocardial fibrosis (1). Cohesive regions of myocardial fibrosis, such as infarcted myocardium, are characterized by expanded extracellular matrix due to replacement of normal myocytes with collagen. Gadolinium contrast agents perfuse into and wash out of normal myocardium relativel...