The Impact of Novel Anticoagulants: Should All AF Patients Now Be Anticoagulated?

Atrial Fibrillation (AF) is accompanied by an increased risk for thromboembolic events in most affected patients. Current guidelines therefore recommend antithrombotic therapy with vitamin K antagonist (VKA) or non VKA oral anticoagulant (NOAC) in the majority of AF patients. Current AF treatment guidelines recommend that only patients younger than 65 years of age with lone AF, meaning without further concomitant risk factors for thromboembolic events should not be anticoagulated. NOACs, like the direct thrombin inhibitor dabigatran and the factor X inhibitors rivaroxaban, apixaban, and edoxaban have undergone large phase III clinical trials concerning treatment efficacy and bleeding risk in comparison to the VKA warfarin. In most cases, treatment with NOACs has been shown to decrease thromboembolic risk and/or decrease bleeding risk when compared with warfarin. Especially, as major hemorrhages like life threatening or intracranial bleeds are reduced, the question arises, if due to favourable adverse event ratios the indication for oral anticoagulation therapy should be broadened and all patients with diagnosed AF should be anticoagulated. This article gives a review on currently used thromboembolic and bleeding risk scores. Furthermore, the impact of NOAC therapy on stroke and bleeding risk is summarized, especially taking pharmacological interactions of NOAC therapy altering thromboembolic or bleeding risk into consideration. Differences of currently available guidelines are discussed. Finally, ongoing recent studies on treatment of low risk patients are debated.