A Randomized Comparison of Double Bolus Urokinase versus Front-Loaded Alteplase Regimen for Acute Myocardial Infarction

Background : This study was performed to compare double bolus urokinase (UK) regimen with front-loaded alteplase regimen for acute myocardial infarction (AMI). Methods : In 26 hospitals, 618 patients with AMI within 6 hours after onset of pain were randomized to receive double bolus UK (UK 1.5 million units intravenous bolus injection, followed by UK 20,000 units /kg intravenous bolus injection 30 minutes after the first dose (up to 1.5 million units) or front-loaded alteplase. Coronary angiography was performed 90 min (N= 200) and/or 7 days (N=303) after thrombolytic therapy. The primary end point was a composite outcome of death, nonfatal reinfarction and nonfatal stroke within 30 days. There were no differences in baseline clinical characteristics. Results : TIMI grade 3 antegrade flow of infarct-related artery at 90 minutes was achieved after treatment with double bolus UK (69.9 %, 79/113) or front-loaded alteplase (67.8 %, 59/87) (p=NS). Angiographic patency at 7 days after thrombolytic therapy was also similar in both groups (81.7 % vs 77.8%). There was no significant difference in 30-day mortality between both groups (4.6 %, 16/350 vs 4.4 %, 12/268 p=NS). The rates of major hemorrhagic strokes was 0.3 % (1/350) in UK group and 1.1 % (3/268) in alteplase group (p=NS). No difference was observed in the rate ofreinfarction between both groups (3.1 %,11/350 vs 3. 4 %, 9/268 , p=NS). A composite outcome was also similar in both groups (8.0 % vs 8.9 %, p=NS ). Conclusions : Double bolus urokinase is an easy, safe and effective thrombolytic regimen with comparable results to standard front-loaded alteplase in the treatment of acute myocardial infarction.ope