The pivotal randomized clinical trials (RCTs) of non–vitamin K antagonist oral anticoagulants (NOACs) for stroke prevention in atrial fibrillation (AF) established the efficacy and safety of these drugs for patients with AF without mechanical prosthetic heart valves or significant (rheumatic) mitral valve stenosis.1 A clinical trial setting with strict inclusion and exclusion criteria was needed to obtain high-quality scientific evidence on the effects of NOACs compared with standard care (ie, warfarin), but these results in highly selected trial cohorts may not be fully applicable to a diversity of patients or clinical circumstances encountered in daily practice.
Potpara TS, Lip GYH. Postapproval Observational Studies of Non–Vitamin K Antagonist Oral Anticoagulants in Atrial Fibrillation. JAMA. 2017;317(11):1115-1116. doi:10.1001/jama.2017.1152