MY APPROACH to the use of NOACs for stroke prevention in patients with atrial fibrillation

Abstract

Stroke prevention is central to the management of atrial fibrillation (AF). The approach is to initially identify patients at a low risk for stroke (CHA2DS2-VASc score of 0 [men] or 1 [women]), who do not need any antithrombotic therapy. Subsequent to this step, patients with Z additional stroke risk factors (thus, CHA2DS2-VASc score of Z2, as well as men with a score of 1) can be offered effective stroke prevention. Effective stroke prevention essentially means oral anticoagulation (OAC), whether given as a well-controlled, adjusteddose vitamin K antagonist (VKA; e.g., warfarin), or one of the non-VKA oral anticoagulants (NOACs; previously referred to as new, or novel, OACs) [1]. If VKAs are used, the challenge is to maintain patients within an international normalized ratio (INR) of 2.0–3.0. Guidelines recommend good-quality anticoagulation control, as reflected by an average individual time in therapeutic range (TTR) of Z70% [2,3]. The TTR correlates with the efficacy and safety of VKAs, whereby a high TTR is associated with low risks for thromboembolism and bleeding, but a low TTR (i.e., o60%) is associated with a high risk for thromboembolism or hemorrhage [3,4]. For newly diagnosed anticoagulation-naive patients with AF, use of the SAMe-TT2R2 score can help identify those patients (SAMe-TT2R2 score of 0–2) who are likely to do well with a VKA (with TTR Z 70%). On the other hand, patients with a