Direct Oral Anticoagulants for Rheumatic Heart Disease-Associated Atrial Fibrillation Post-Bioprosthetic Mitral Valve Replacement.

Background: The efficacy of direct oral anticoagulants (DOACs) in preventing ischemic and thromboembolic events may be suboptimal in atrial fibrillation (AF) patients with rheumatic mitral stenosis. However, their safety and effectiveness after mitral valve replacement (MVR) using bioprosthetic valves is unclear.

Objectives: This study sought to evaluate the safety and effectiveness of DOACs vs warfarin among patients with rheumatic heart disease (RHD)-associated AF after bioprosthetic MVR.

Methods: We performed an observational analysis identifying patients with RHD and AF who underwent bioprosthetic MVR. Primary effectiveness and safety outcomes were ischemic events and major bleeding, respectively. Secondary outcomes included all-cause mortality, cardiac thrombosis, myocardial infarction, and all-cause hospitalization. Propensity score matching was performed to account for the differences in baseline characteristics and comorbidities.

Results: A total of 3,950 patients were identified; 76% were on warfarin and 24% on DOAC post-MVR. The DOAC group had a higher burden of baseline comorbidities and prior cardiovascular procedures compared with the warfarin group. The propensity score matching balanced baseline characteristics in 1,832 patients (916 in each group), with a mean age of 69 years. At the 5-year follow-up, DOACs were associated with a lower incidence of major bleeding compared with warfarin (HR: 0.76; 95% CI: 0.62-0.94), with no significant difference in ischemic events, mortality, cardiac thrombosis, myocardial infarction, or hospitalization.

Conclusions: Among patients with RHD-associated AF patients post-bioprosthetic MVR, DOACs are associated with lower major bleeding and comparable effectiveness, indicating a potential alternative to warfarin. Further randomized controlled trials are warranted to validate these findings in this population.