Anticoagulation during the hospital phase of acute myocardial infarction reduced mean case fatality rates compared to control (15.4% vs 19.6%, a relative reduction of 21%; P<0.05).
Meta-Analysis
Do anticoagulants reduce case fatality in patients hospitalized for acute myocardial infarction?
Pooling of randomized trials shows that anticoagulation during hospitalization for acute myocardial infarction significantly reduces case fatality by 21%.
Effect estimate: Relative reduction 21%
Absolute Event Rate: 15.4% vs 19.6%
p-value: p=<0.05 or <0.001
Abstract Since the last comprehensive review of anticoagulation in acute myocardial infarction four additional randomized control trials have been reported. The overwhelming majority of all trials favored anticoagulation. Rates of thromboembolism were higher in the control, and hemorrhagic complications in the anticoagulated group. Pooling of all randomized control trials gives mean case fatality rates of 19.6 per cent for the control and 15.4 per cent for the anticoagulated group, a relative reduction of 21 per cent (P<0.05 or <0.001, depending on the analytic method). Five of six randomized control trials reported "no effect" because the difference favoring anticoagulation was not statistically significant. However, sample sizes in these "negative" papers were too small to protect against missing a 21 per cent reduction in true case fatality rate due to anticoagulation (β<0.10). All patients who present no specific contraindication should receive anticoagulants during hospitalization for infarction. (N Engl J Med 297:1091–1096, 1977)
Chalmers et al. (1977) conducted a meta-analysis in Acute Myocardial Infarction. Anticoagulants vs. Control was evaluated on Mean case fatality rate (Relative reduction 21%, p=<0.05 or <0.001). Anticoagulation during the hospital phase of acute myocardial infarction reduced mean case fatality rates compared to control (15.4% vs 19.6%, a relative reduction of 21%; P<0.05).