Long-term follow-up after intracoronary streptokinase for myocardial infarction: A randomized, controlled study

Abstract

Intracoronary streptokinase (SK) may have beneficial effects on the in-hospital course of acute myocardial infarction (MI), but long-term outcome is unknown. We evaluated the outpatient course of 50 MI patients, randomly treated with either SK (n = 24) or standard therapy (n = 26), who presented within 2.7 ± 0.7 hours of symptoms. Coronary reperfusion occurred in 19 (79%) SK patients. Survivors were followed for a mean of 18.7 months (range 11 to 28.5); information was current in 48 patients (96%). Both groups received antiplatelet therapy for 3 months. A total of five deaths occurred in the control group and two in the SK group, including one posthospital death in each. Nonfatal MIs totaled five in control patients and three in SK patients, including five posthospital MIs (three control, one SK). Differences in major events (death or nonfatal MI) favoring SK did not quite reach statistical significance (10 control vs 5 SK). Bypass surgery was performed in seven SK and four control patients (NS). Angina occurred in more control (15) than SK (six) patients ( p < 0.01), and more control patients used long-acting nitrates (14 control, three SK; p < 0.01). Palpitations were noted by nine control and one SK patient ( p < 0.01), and documented late arrhythmias were present in four control patients and no SK survivors ( p < 0.05). Symptoms suggestive of heart failure were present in seven control and one SK patient ( p < 0.01); two control patients were hospitalized for failure. Use of beta blockers, calcium channel blockers, and other cardiac medications did not differ. Activity status was also similar. ECGs in surviving patients at 6 weeks revealed an average of 4.2 ± 2.4 Q waves in control vs 3.1 ± 1.5 in SK patients (trend NS). Early catheterization with application of SK within about 4 hours of MI was associated with continued favorable clinical trends after 1 1 2 years .