Abstract
Atrial fibrillation (AF) is the most common significant cardiac rhythm disorder, and
its prevalence is increasing worldwide. Atrial fibrillation confers a fivefold increased
risk of stroke, and these strokes are associated with significant mortality and disability.
The vitamin K antagonist, warfarin, has been the mainstay of anticoagulant therapy
for patients with AF, reducing the risk of stroke by 65%. Despite its efficacy, warfarin
remains underused in clinical practice because of its variable dose response, diet
and medication interactions, and need for frequent monitoring. Stroke prevention in
AF has entered an exciting therapeutic era with new classes of targeted anticoagulants
that avoid the many pitfalls of the vitamin K antagonists. Dabigatran, an oral thrombin
inhibitor, and the factor Xa inhibitors, rivaroxaban and apixaban, have demonstrated
efficacy for stroke prevention and a reduced risk of intracranial hemorrhage relative
to warfarin. Translating the efficacy of clinical trials into effective use of these
novel agents in clinical practice will require an understanding of their pharmacokinetic
profiles, dose selection, and management in select clinical situations.
Keywords
atrial fibrillation - anticoagulation - stroke - hemorrhage
