A randomized controlled trial of intravenous streptokinase in evolving acute myocardial infarction

To determine the efficacy of intravenous streptokinase in acute myocardial infarction, 52 patients were randomized to intravenous streptokinase or control groups. Time from onset of infarction to randomization was similar in the streptokinase group and control group, 4.9 ± 2.1 hours vs 5.4 ± 2.4 hours, respectively. The 28 streptokinase patients received an intravenous infusion of 700,000 units of streptokinase followed by full-dose anticoagulation. The 24 control patients received normal saline solution followed by full-dose anticoagulation. Of 28 streptokinase patients, 12 (43%) had noninvasive evidence of reperfusion by early peaking of serum creatine kinase (peak creatine kinase less than 16 hours after onset of infarction) vs 3 of 24 control patients (13%), p < 0.02. Two streptokinase patients (7%) had reperfusion arrhythmias during streptokinase infusion. One streptokinase patient (4%) and two control patients (8%) died during hospitalization. At angiography (16 ± 5 days after infarction) 22 of 26 streptokinase patients (85%) had a patent infarct-related coronary artery compared to 8 of 20 control patients (40%), p < 0.01. Comparison of radionuclide left ventricular ejection fraction assessed acutely (28 ± 10 hours after infarction) with left ventricular ejection fraction at hospital discharge (15 ± 3 days after infarction) showed no significant improvement in either the streptokinase or control group, 0% and +1%, respectively. At follow-up 13 ± 7 months after infarction, total mortality rate was similar in the streptokinase group and control group, 17.8% (5 of 28 streptokinase patients) and 20.8% (5 of 24 control patients), respectively. These results indicate that the incidence of a patent infarct-related coronary artery 2 to 3 weeks after acute myocardial inf arction was significantly greater in patients who received intravenous streptokinase compared to control patients.