Thrombolytic therapy for acute myocardial infarction-effects, problems and strategies.

The effects and problems of coronary thrombolysis (CT) were investigated in 652 patients with initial acute myocardial infraction (AMI). Nosocomial mortality obtained by matching factors which determined prognosis was significantly lower in patients treated by CT (8.3%) than in those who did not undergo CT (18.1%). Regardless of whether the treatment was intracoronary arterial (ICT) or intravenous (IVCT), the primary cause of the decreased mortality was reperfusion of the coronary artery responsible for infarction (mortality 6.1% in the reperfused group vs 21.5% in the ineffective group). CT therapy improved left ventricular ejection fraction (LVEF), the nosocomial mortality rate, and regional wall motion at the site of infarction in cases that were reperfused less than 3 h, 3-6 h, and even 6 or more hours after the therapy. The long-term prognosis was significantly better in the reperfused group than in the ineffective group for 5 years and 7 months after therapy. However, CT was accompanied by both (1) poor prognosis in the ineffective group; and (2) unfavorable effects on the prognosis and on the daily life of patients with severe stenosis even after treatment. Accordingly, supplemental ICT and rescue PTCA (strategy (A)) were performed to treat the first problem, and deferred PTCA (strategy (B)) was conducted to treat the second problem in 80 patients with initial AMI. As a result, strategy (A) increased the coronary reperfusion rate to 94.3%, and strategies (A) and (B) together decreased the nosocomial mortality rate of 8.5% to 3.8%, and reduced the risk of death by 55.3%.