A Systematic Approach to Stroke Prevention for Patients with Atrial Fibrillation
Strokes occurring as a result of atrial fibrillation are common and typically result in severe disability or death. Over the past half century, therapeutic options for stroke prophylaxis, based on either antiplatelet (typically acetylsalicylic acid) or warfarin therapy, have remained virtually unchanged. However, as of mid-2011, promising data have emerged and Health Canada has approved a novel oral anticoagulant, dabigatran. This article provides a systematic 4-step process to guide clinicians in assessing, implementing and monitoring stroke prophylaxis for individual patients. First, identify the patient's risk of stroke with user-friendly scoring systems (CHADS2 and CHA2DS2-VASc). Second, determine the patient's risk of major bleeding with a validated scoring system (HAS-BLED) and ongoing clinical evaluation. Third, balance these benefits and the risks of available agents as they pertain to the individual patient. Fourth, select the appropriate antithrombotic therapy, with an understanding of the key features of available agents, as well as the patient's characteristics and preferences. Regular monitoring and patient adherence with therapy are necessary to ensure the long-term appropriateness of therapy, given that most patients with atrial fibrillation will require lifelong stroke prophylaxis and an individual's stroke risk generally increases with age. The pharmacist is in an excellent position to provide this type of assessment and follow-up.