Abstract
Oral anticoagulation is the most effective drug for stroke prevention in atrial fibrillation (AF). Until recently, the only oral anticoagulant drug class available for our clinical use is the Vitamin K antagonists (VKAs, e.g. warfarin). Nonetheless, warfarin use is limited by significant inter- and intra-patient variability, as well as the dis-utility of needing anticoagulation monitoring (to keep within a narrow therapeutic range) and the diet/drug/alcohol restrictions associated with these drugs. Thus, prior stroke risk stratification guidelines have tried to artificially divide patients into low, moderate and high stroke risk strata, eventhough these categories do not have good predictive ability. Given the dis-utility associated with the VKAs, uptake of oral anticoagulation is also limited, with high rates of discontinuation after initiation. With the availability of new oral anticoagulant drugs (either the oral direct thrombin inhibitors or oral Factor Xa inhibitors class of drugs), a paradigm shift has been made towards getting better at identifying truly low risk patients who do not need any antithrombotic therapy, whilst those patients with one or more stroke risk factors can be considered for oral anticoagulation. The latter can be given as well controlled warfarin, or one of the new oral anticoagulants. This approach is recommended within the 2010 European Society of Cardiology guidelines for the management of AF.
