Atrial fibrillation (AF), the most common, clinically significant,
cardiac arrhythmia affects 1% of the general population and has important hemodynamic and thromboembolic complications that contribute to elevated morbidity and mortality. AF increases the overall risk of
stroke five-fold, accounting for approximately 15% of all
strokes and is associated with particularly severe
stroke. For the last 50 years, long-term anticoagulation with
vitamin K antagonists has been the most effective
therapy for preventing
stroke and systemic
embolism in patients with AF and other risk factors, but their use has a lot of limitations and drawbacks (frequent monitoring and dose adjustment, food and drug interactions, delayed onset of action etc). Nowadays, new oral
anticoagulants have emerged that seem to overcome those limitations.
Direct thrombin inhibitor dabigatran and
factor Xa inhibitors rivaroxaban and
apixaban have proven, in large, multicenter, randomized, phase III, clinical studies, to be at least as efficient as
warfarin in
stroke prevention in patients with AF. RELY and ROCKET AF trials have contributed to market approval of
dabigatran and
rivaroxaban, respectively and made them available to clinical practice. Another
factor Xa inhibitor,
edoxaban, is under evaluation in an ongoing phase III clinical trial and others such as
AZD0837,
betrixaban and
darexaban are still in safety and tolerability phase II studies. The oral anticoagulation landscape is changing rapidly and these new agents seem to be very promising. However future post-marketing studies and registries will help clarify their efficacy and safety.