Stroke Prevention in Atrial Fibrillation
New Oral Anti-Coagulants
Atrial Fibrillation (AF) is a common sustained arrhythmia and can increase the risk of stroke by up to 20-fold. Strokes in AF assume special significance as they tend to be larger, recurrent and likely to produce significant disability or death. A formal risk stratification by tools like CHA2DS2-Vasc and HAS-BLED scoring systems, is recommended to correctly identify and treat such patients with long term anti-coagulation. Several New Oral Anti-coagulants (NOACs) have been developed as specific inhibitors to the clotting factors in the coagulation cascade (e.g. thrombin or Factor Xa). Four of them namely Dabigatran, Rivaroxaban, Apixaban and Edoxaban have completed phase III clinical trials and have been approved for clinical use in non-valvular AF for stroke prevention. NOACs in general are non-inferior (some even superior) to warfarin in reducing risk of stroke and thrombo-embolic complications, with equivalent or less bleeding complications, even without the need for regular INR monitoring.