Anticoagulant therapy and atrial fibrillation

Summary

Atrial fibrillation is the most frequent supraventricular arrythmia and is associated with increased morbidity and mortality. Patients with any form of atrial fibrillation have significantly higher risk of stroke and systemic embolism. Therefore, anticoagulation therapy is needed to prevent and treat cardioembolic events in such patients. According to updated 2010 European Guidelines for Diagnosis and Treatment of atrial fibrillation, the patients should be stratified and indicated to anticoagulation therapy based on their risk of stroke using the CHA₂DS₂-VASc scoring system but with regards to their bleeding risk as calculated by the HAS-BLED score. Novel anticoagulant agents that interfere with the coagulation cascade at different levels and have markable advantages over vitamin K antagonist – warfarin have been developed. These include a direct thrombin inhibitor dabigatran (RE-LY study), factor Xa inhibitors rivaroxaban (Rocket AF study) and apixaban (AVERROES, ARISTOTLE studies). Another anti-Xa agent edoxaban is being tested in a large clinical trial (ENGAGE).

Keywords:
atrial fibrillation – CHA₂DS₂-VASc-VASc score – warfarin – novel anticoagulants – dabigatran – 
apixaban – rivaroxaban – edoxaban