Anticoagulation in atrial fibrillation : Current evidence and guideline recommendations

Atrial fibrillation (AF) is the most frequently encountered sustained arrhythmia with a prevalence of 0.5-10%, depending predominantly on age. The arrhythmia is associated with significant morbidity and mortality, mainly due to thromboembolic events including stroke and systemic embolisms. These complications can be effectively prevented with anticoagulation therapy either with vitamin K antagonists (VKA) or with non-vitamin K antagonists (NOAC). VKA therapy is effective in preventing strokes but these medications are difficult to use, are associated with significant bleeding risk, and have pharmacokinetic/dynamic properties that make their use cumbersome. NOACs-either factor II or factor Xa inhibitors-have been developed over the past two decades and have been tested against VKA in large randomized controlled trials. This trial evidence was complemented more recently by increasing real-world data comprising several 100,000 patients. Finally, NOACs have been examined for their use in specific clinical situations, for example, in patients undergoing cardioversion, catheter ablation, or coronary interventions. In all of these clinical scenarios, NOACs have been similarly effective or-in many instances-even superior to treatment with VKA. Recent guidelines, therefore, recommend NOAC therapy for stroke prevention in AF as first-line therapy.