Comparison of bleeding complications and 3-year survival with low-molecular-weight heparin versus unfractionated heparin for acute myocardial infarction: The FAST-MI registry

Background: Recent clinical studies suggest that low-molecular-weight heparin (LMWH) could be an effective and safe alternative to unfractionated heparin (UFH) for patients with acute myocardial infarction (AMI). Aims: To assess the impact of anticoagulant choice (LMWV vs UFH) on bleeding, the need for blood transfusion and 3-year clinical outcomes in AMI patients from the FAST-MI registry. Methods: FAST-MI was a nationwide registry compiled in France over 1 month in 2005, which included consecutive AMI patients admitted to an intensive care unit less than 48 hours from symptom onset in 223 participating centres. Results: A total of 2854 patients treated with heparins were included. The risks of major bleeding or transfusion (3.0% vs 7.0%) and in-hospital death (3.2% vs 9.2%) were lower with LMWH compared with UFH, a difference that persisted after multivariable adjustment (odds ratio [OR] 0.51, 95% confidence interval [CI] 0.34-0.76 and OR 0.53, 95% CI 0.37-0.76, respectively). Three-year survival, and stroke and reinfarction-free survival risks were also higher with LMWH compared with UFH (adjusted hazard ratio [HR] 0.73, 95% CI 0.61-0.87 and HR 0.73, 95% CI 0.62-0.85, respectively). In two cohorts of patients matched on propensity score for receiving LMWH and with similar baseline characteristics (834 patients per group), major bleeding and transfusion rates were lower while the 3-year survival rate was signicantly higher in patients receiving LMWH. Conclusion: Our data suggest that the use of LMWH in AMI patients may have a better benefit/risk profile than UFH, in terms of bleeding, need for transfusion and long-term survival.