Efficacy and safety of a new streptokinase regimen with Enoxaparin in acute myocardial infarction

Objective: To compare a new streptokinase regimen combined with either enoxaparin or unfractionated heparin (UFH) and the traditional streptokinase regimen combined with UFH in patients with acute myocardial infarction (AMI). Methods: 412 patients (< 75 years), hospitalized within 6 hours of the onset of chest pain, were allocated thrombolytic therapy by the treating physician: streptokinase 0.75 MU/10 minutes, repeated if no coronary reperfusion after one dose, plus enoxaparin 40 mg intravenously followed by 1 mg/kg bodyweight subcutaneously at 12-hour intervals for 5 - 7 days (n = 102); the same streptokinase regimen plus UFH 1000 IU/60 minutes intravenously for 48 - 72 hours ( n = 106); or streptokinase 1.5 MU/60 minutes plus the same UFH regimen ( n = 204). All patients received 250 - 325 mg aspirin/day. Coronary reperfusion rates, 30-day mortality and hemorrhagic complications were recorded. Results: Coronary reperfusion rates with 0.75 streptokinase + enoxaparin (78.4%) and 0.75 streptokinase + UFH (74.5%) were significantly higher than those with 1.5 streptokinase + UFH (62.2%), but there was no significant difference between the groups receiving the new regimen. Overall 30-day mortality (6.3%) was significantly lower than with 1.5 streptokinase + UFH (12.7%) ( p = 0.037). The incidence of major and minor hemorrhagic events was similar in all groups. Conclusions: The accelerated streptokinase regimen was well tolerated and resulted in a significantly higher coronary reperfusion rate and significantly lower mortality compared with the traditional regimen. The 0.75 streptokinase + enoxaparin combination was at least as efficacious as the 0.75 streptokinase + UFH combination and is preferred because of its ease of administration and predictable anticoagulant effect.