Adopting the new anticoagulants: all aboard or all in good time?

Abstract

At last there is now more than 1 oral anticoagulant (OAC) available for stroke prevention in atrial fibrillation. Though more choice is a good thing, it does mandate knowing which drug is the most appropriate in a given clinical situation. Three novel OACs--dabigatran, rivaroxaban, and apixaban--are approved for use in atrial fibrillation in Canada. They have each been evaluated in large, randomized controlled trials where they have been shown to be noninferior, or in some cases superior, to warfarin (Coumadin). Prescription coverage for these drugs is increasingly available through third party and government drug plans. The major enhancements of the novel OACs relate to their rapid, consistent anticoagulant effect at fixed dosing and the lack of need for monitoring of anticoagulant effect. Nonetheless, their use is not foolproof and practitioners must be familiar with their limitations. On balance, we favour the use of novel OACs over warfarin in patients who are anticoagulant-naive, given their increased ease of use. However, we advocate switching from warfarin only if international normalized ratio control has been poor or if frequent monitoring is problematic.