Abstract 5597: Does Warfarin-Based Anticoagulation Improve Outcomes After Acute Myocardial Infarction? A Meta-Analysis of Randomized Clinical Trials
Antiplatelet therapy is the principal component of the antithrombotic regimen after acute myocardial infarction (AMI). It remains unclear whether additional routine antithrombin therapy with chronic oral anticoagulation (OAC) improves outcomes. Using the Ovid SP and PubMed databases, we performed a comprehensive search for randomized clinical trials comparing warfarin-containing regimens with or without aspirin (OAC) with non-warfarin-containing regimens with or without aspirin (No OAC) for patients with recent AMI, regardless of reperfusion and adjunctive medical therapies provided during hospital stay. The studies had to provide follow-up for at least one month and have mortality as endpoint. Meta-analysis techniques were employed to calculate the relative risk (RR, fixed effect) for all-cause death at the longest interval of follow-up available. Between 1965 and 2006, 32 studies were identified and 11 were included in the meta-analysis. Among 23,803 patients, 13,070 were assigned to OAC and 10,733 to No OAC. The patients were followed for 3–79 months. Death occurred in 1,199 and 1,162 patients, respectively, RR 1.00 (0.995–1.010) (Figure⇓). After excluding studies without background aspirin therapy, death occurred in 1,057 and 993 patients, respectively (8 studies, RR 1.00 [0.992–1.008]). OAC with or without aspirin background therapy does not reduce mortality after AMI.