The influence of reperfusin on infarct size after experimental coronary artery occlusion

Reperfusion following various intervals of coronary occlusion has produced conflicting results: increase in infarct size, especially with hemorrhage into the tissue, was reported as well as salvage of ischemic myocardium. To examine the problem and for the validation of our own method for infarct size measurement, which depends to a certain degree on reperfusion, we occluded two coronary arteries of the same heart in each of 12 open-chest dogs. One artery was reperfused, the other not. Comparable conditions for both occlusions were warranted by selection of small-to-medium sized arteries of equal size and by maintaining of constant MVO2. Reperfused and non-reperfused myocardium did not differ with regard to infarct size, neither after a three-hour nor after a six-hour occlusion. Reperfusion always led to hemorrhagic infarction when performed after six-hour occlusion, while nonreperfused infarctions showed no hemorrhage. Hemorrhage infarcts were not larger as compared to the non-hemorrhagic infarct in the same heart.