Reversibility and Pathohistological Basis of Left Ventricular Remodeling in Hibernating Myocardium

Abstract The phenomenon of left ventricular (LV) remodeling with dilatation, wall thinning, and increased muscle mass has previously been reported in pigs with 7-day myocardial hibernation. This study investigated cellular and extracellular basis and reversibility of the structural LV remodeling with hibernating myocardium. Five groups of pigs were included: Group A: 7-day myocardial hibernation with a fixed coronary stenosis; Group B: 7-day hibernation with subsequent 3-week reperfusion by release of the stenosis; Group C: control group with sham operation; Group D: 24-hour myocardial hibernation to define structural mechanism of initial wall thinning in the hibernating region without confounding factors of cell loss or hypertrophy, Group E: 4-week myocardial hibernation to exclude the possibility of spontaneous regression of LV remodeling with hibernation. LAD flow decreased by 38 ± 12% ( p p