Angiographic patency study of anistreplase versus streptokinase in acute myocardial infarction.

128 patients with acute myocardial infarction of duration 6 h or less were randomised in double-blind fashion to receive 30 U anistreplase over 5 min or 1.5 MU streptokinase over 1 h, both intravenously. Angiographic patency was assessed 90 min and 24 h from the start of therapy. 55% of patients who received anistreplase and 53% of patients who received streptokinase had patent infarct-related arteries (TIMI grade 2-3) at 90 min (95% CI 42-68% and 40-66%, respectively). At 24 h 81% and 87.5% of arteries were patent respectively (95% CI, 71-91% and 83.5-91.5%). Time to therapy had no significant effect on patency rates. There was one early reocclusion within 24 h in each treatment group and clinical evidence of reocclusion was recorded between 24 h and hospital discharge in a further 5 patients (streptokinase 3, anistreplase 2). With these regimens, therefore, anistreplase and streptokinase gave the same patency rates.