[Fibrinolytic treatment of acute myocardial infarction (author's transl)]

Fibrinolytic treatment of acute myocardial infarction with streptokinase and urokinase has now been under investigation for almost 20 years. Initially encouraging reports of beneficial effects of streptokinase were not substantiated by carefully controlled studies performed on coronary care and intensive care units. Studies carried out during the last tne years were characterized by non-uniform trial conditions and results. Similarly, to date no clearly beneficial effects of urokinase could be established. In order to provide more concise analysis, the "European Cooperative Study Group for Streptokinase Treatment in Myocardial Infarction" conducted a multi-center controlled trial. Patients were allocated to risk-groups. Three-hundred fifteen patients with medium and high risk were randomized to a 24-hour infusion of streptokinase or glucose. The overall mortality within six months was significantly lower in the streptokinase group (p less than 0.01) contributed primarily by eight of the eleven centers. Only 13.5% of patients with myocardial infarction, however, were eligible for the study. Interpretation of the results yielded no indication of the nature of the fibrinolytic effects nor how the benefit could be explained pathophysiologically. Furthermore, it remains questionable whether systemically-administered streptokinase can lyse coronary thrombosis or reduce the size of myocardial necrosis. An indirect effect of streptokinase through lowering of blood viscosity and subsequently, peripheral capillary resistance may represent a theoretical possibility. the indication of routine systemic administration of streptokinase has not yet been established. Recent reports of promising results obtained by direct, intracoronary infusion of thrombolytic agents indicate that this alternative may lead to realization of a specific effect in reduction of coronary thrombosis and, consequently, myocardial necrosis.