[Reperfusion of the myocardium after acute ischemic lesion]

In a complex experimental study on 52 dogs the myocardium was examined after ischemia and reperfusion of various duration. Morphologic, metabolic, and functional findings proved that a short-term reperfusion after coronary occlusion for more than 2 hours has disadvantageous effects on the regression of ischemic lesions. During the early period (up to 3 days) this is caused by the "no-reflow" phenomenon. Combined qualitative and quantitative findings are required for correct appraisal of the ultrastructural alterations after reperfusion. In acute coronary occlusion, early revascularization after passing the crucial initial phase is advantageous, because the extent of myocardia necrosis is decreased by the prolonged reperfusion, thus leaving a larger myocardiac reserve in case of re-infarction. Clinical conclusions are drawn.