New Oral Anticoagulants Versus Warfarin in Atrial Fibrillation After Early Postoperative Period in Patients With Bioprosthetic Aortic Valve

Background: The efficacy of novel nonvitamin K antagonist oral anticoagulants (NOACs) in nonvalvular atrial fibrillation (AF) to prevent stroke is well assessed, but NOACs use in AF that occurs after bioprosthetic aortic valve replacement (AVR) is not endorsed. This retrospective real-world study evaluated the efficacy and safety of NOACs prescribed no earlier than 4 months after AVR as an alternative to warfarin in patients with AF. Methods: We pooled 1032 patients from the databases of 5 centers. Ischemic/embolic events and major bleeding rates were compared between 340 patients assuming NOACs and 692 prescribed warfarin. Propensity score matching was performed to avoid the bias between groups. Results: The NOACs vs warfarin embolic/ischemic rate was 13.5% (46 of 340) vs 22.7% (157 of 692), respectively, (hazard ratio [HR], 0.5; 95% confidence interval [CI], 0.37-0.75; P < .001), and the incidence rate was 3.7% vs 6.9% patients/year, respectively (log-rank test P = .009). The major bleeding rate was 7.3% (25 of 340) vs 13% (90 of 692) (HR, 0.5; 95% CI, 0.33-0.84; P = .007), and the incidence rate was 2% vs 4% patients/year (log-rank test P = .002.) After propensity score matching, the NOACs vs warfarin embolic/ischemic rate was 13.1% (42 of 321) vs 21.8% (70 of 321) (HR, 0.6; 95% CI, 0.4-0.9; P = .02), and the incidence rate was 4.1% vs 6.7% patients/year (log rank test P = .01). The major bleeding rate was 7.8% (25 of /321) vs 13.7% (44 of 321) (HR, 0.5; 95% CI, 0.31-0.86; P = .01), and the incidence rate was 2.4% vs 4.2% patients/year (log-rank P = .01). Conclusions: In a real-word study, NOACs use overcomes the indications provided by guidelines. This study evidenced that NOACs use in patients who developed AF after bioprosthetic AVR was more effective in prevention of thromboembolism and safe in reduction of major bleeding events compared with warfarin.