Purpose of review: As anticoagulant therapy is a cornerstone in the early management of acute coronary syndrome, the question remains whether long-term anticoagulation after discharge will further improve outcome.
Recent findings: Major trials demonstrated benefit from routine oral anticoagulation with an attained international normalized ratio over 2.0 in patients after myocardial infarction. However, the benefit seen in these trials was achieved at the expense of increased bleeding and high dropout rate. In addition, a significant number of patients in both these trials had an international normalized ratio below the target range. Furthermore, the trials were performed before the clopidogrel era in which the great majority of patients with both non-ST-elevation and ST-elevation acute coronary syndromes are treated with an early invasive strategy. The benefit with warfarin therapy is in the range of benefit seen with clopidogrel, which is easier to administer, and there are no data assessing a possible benefit of warfarin therapy in patients taking aspirin and clopidogrel in whom the bleeding risk might be excessive. Very recently, direct oral thrombin blockade has been developed and found to be effective in venous thromboembolism and after myocardial infarction. In addition, oral direct factor Xa blockers are also good candidates for replacing warfarin.
Summary: Oral anticoagulation after myocardial infarction is beneficial but increases bleeding risk and is notoriously difficult to monitor. Novel oral anticoagulants are currently evaluated for this indication with aspirin and clopidogrel as background therapy.