Stroke Prevention in Atrial Fibrillation: Pharmacologic Update

For nearly half a century, the therapeutic options for the risk reduction of stroke in atrial fibrillation have been stagnant with vitamin K antagonists, such as warfarin, being the primary therapy. Although antiplatelet agents have been investigated over this time, they were never shown to reduce the risk of stroke at the level warfarin has. Considering the limited therapeutic options, the main decision facing clinicians was not determining which agent to use, but whether a patient was at high enough risk of stroke to benefit from anticoagulation. The CHADS2 and, more recently, the CHADSVASC risk assessment schemes have been shown to be a simple and predicable tool in determining an individual's risk for stroke. Now, after nearly 50 years with limited alternatives, there has been a surge in therapies in the form of dabigatran, rivaroxaban and apixaban, which have been shown to be non-inferior and in some cases, superior to warfarin in their respective randomized controlled trials. This increase in available options is exciting but at the same time adds another layer of confusion to the process of selecting the appropriate agent for individual patients.