Efficacy and Safety of Nonvitamin K Oral Anticoagulants following Cardiac Valve Replacement.

Abstract

To compare the efficacy and safety of nonvitamin K oral anticoagulants (NOACs) and vitamin K antagonists (VKAs) following bioprosthetic cardiac valve replacement. This was a retrospective analysis conducted at a community teaching hospital in the southeastern United States between August 2015 and August 2018. Patients 18 years of age and older who underwent cardiac valve replacement and were prescribed oral anticoagulation were screened for inclusion. Patients were excluded if they had a mechanical valve replacement, experienced a venous thromboembolism, cerebrovascular accident, or acute coronary syndrome within 1 month before valve replacement, changed oral anticoagulation during the study period, were lost to follow-up, or declined to participate in the follow-up survey. The primary outcome was a composite of thromboembolic events within 90 days following bioprosthetic cardiac valve replacement. The safety outcome was major bleeding within 180 days of bioprosthetic cardiac valve replacement. The primary outcome of a composite of thromboembolic events within 90 days following bioprosthetic cardiac valve replacement occurred in 1 patient (4.3%) in the VKA group and 4 patients (7.4%) in the NOAC group. Major bleeding occurred in 2 patients (8.7%) in the VKA group and 0 patients in the NOAC group. Our study is the first to report the efficacy and safety of NOACs compared with VKA therapy following bioprosthetic cardiac valve replacement irrespective of an atrial fibrillation diagnosis. Notably, two of the thromboembolic events in the NOAC group occurred while therapy was held or inappropriately dosed; when these events are removed, the rate of thromboembolism is 3.8%. This rate is consistent with the VKA group. Our study adds to a small pool of literature regarding the use of NOACs following bioprosthetic cardiac valve replacement and suggests that NOACs may have similar efficacy and improved safety as compared with VKA therapy. Large randomized controlled trials are warranted to confirm our observations.