METAANALYSIS OF ALL AVAILABLE PUBLISHED CLINICAL-TRIALS (1958-1990) ON THROMBOLYTIC THERAPY FOR AMI - RELATIVE EFFICACY OF DIFFERENT THERAPEUTIC STRATEGIES

Data of approximately 100000 acute myocardial infarction (AMI) patients, having been treated in 300 clinical trials on thrombolysis for AMI, were included in a meta-analysis comparing the relative efficacy of currently employed plasminogen activators and investigating the influence of early versus late initiation of conjunctive heparin therapy. Early patency after thrombolysis with novel plasminogen activators or intracoronary lysis was significantly higher in comparison with standard streptokinase; this superiority however, did translate into significantly lower mortality rates only for rt-PA. Early initiation of heparin anticoagulation exerted only little influence on early patency, which appears to be determined by the thrombolytic strategy. Reocclusion rates showed a weak correlation with patency; a clear reduction of reocclusion rates was seen when heparin was initiated early. Cumulative in-hospital mortality rates ranged from 4% to 9%. The effects of heparin on mortality were variable; a statistically significant reduction of mortality was noted after rt-PA but not after streptokinase and APSAC, when early versus late conjunctive heparin was compared. Early initiation of anticoagulant therapy is mandatory after thrombolysis with rt-PA; the time of initiation of prophylactic anticoagulation after streptokinase or APSAC did not influence the outcome significantly. Thrombolytic therapy with i.v. rt-PA proved to be superior to all other thrombolytic strategies currently employed, provided, an effective antithrombotic treatment is coadministered.