Intracoronary thrombolysis in patients with acute myocardial infarction: comparison of the efficacy of urokinase with streptokinase.

The efficacy of intracoronary urokinase and streptokinase were compared in 80 patients with acute myocardial infarction in a prospective, randomized, double-blind study. Urokinase was infused into the occluded coronary artery at 6000 U/min, and streptokinase was infused at 2000 U/min. Maximal duration of infusion was 2 hr. The frequency of successfully opening the artery was similar for patients receiving urokinase (27 of 45, 60%) and those receiving streptokinase (20 of 35, 57%). Fibrinogen levels after infusion were measured in 63 patients. Nineteen of 29 streptokinase recipients had fibrinogen levels less than 100 mg/dl compared with levels of two of 34 urokinase recipients (p less than .001). Five of 45 (11%) patients receiving urokinase and 10 of 35 receiving streptokinase (29%) had bleeding complications (p less than .05). Major bleeding after early coronary artery bypass surgery was more frequent in the streptokinase group (four of five compared with a similar group of patients receiving urokinase (none of five). This study demonstrates that while urokinase and streptokinase have equal intracoronary thrombolytic efficacy, patients receiving urokinase have less systemic fibrinolysis and less perioperative bleeding with early surgery than do patients receiving streptokinase.