Presentation available
DISCUSSANT : Hamm, C.W.
Enoxaparin (Enox) has pharmacologic advantages over unfractionated heparin (UFH). Accordingly, it has been investigated in different scenarios when thrombotic processes play a role. The ExTRACT-TIMI 25 study compared a strategy of Enox versus UFH as adjunctive therapy for fibrinolysis among patients with ST-elevation myocardial infarctions. The present prospectively planned subanalysis evaluated the hypothesis that a strategy of Enox (7 days) is superior to UFH (at least 48 hours) among patients who subsequently undergo PCI. Out of 20.479 patients randomized 4.676 (22.8%) underwent subsequent PCI (~2.8% rescue) at the discretion of the treating physicians; 47% of patients were still blinded to the study drug. These patients were younger, had a lower TIMI risk score and a better adjunctive treatment (statins, GP IIb/IIIa antagonists, clopidogrel). Fewer patients underwent PCI through 30 days in the Enox vs UFH groups (22.8% vs 24.2%, p=0.027). By 30 days, the primary end point (death, non-fatal MI) occurred in 10.7% of the Enox and 13.8% of the UFH patients (0.77 relative risk [RR]; P<0.001) driven by delayed onset and reduced recurrence of MI. This was achieved without differences in bleeding complications. Despite the value of these findings for planning the PCI strategy post AMI reservations remain related to selection bias of patients, dosing of Enox, and length of treatment.