- Question
- In patients with atrial fibrillation and a mitral bioprosthetic valve, is rivaroxaban noninferior to warfarin?
- Design
- Randomized, open-label (unmasked), noninferiority trial enrolling 1005 patients at 49 sites in Brazil, with 12 months of follow-up.
- Population
- Patients with atrial fibrillation and a bioprosthetic mitral valve.
- Intervention
- Rivaroxaban 20 mg once daily (15 mg for patients with creatinine clearance of 30 to 49 mL/min per 1.73 m2).
- Control
- Dose-adjusted warfarin targeting an INR of 2.0 to 3.0.
- Primary outcome
- Composite of death, major cardiovascular events (stroke, transient ischemic attack, systemic embolism, valve thrombosis, or hospitalization for heart failure), or major bleeding at 12 months, analyzed as mean time to first event.
- Results
- A primary-outcome event occurred at a mean of 347.5 days with rivaroxaban and 340.1 days with warfarin (restricted mean survival time difference 7.4 days; 95% CI -1.4 to 16.3; P<0.001 for noninferiority). Stroke occurred in 0.6% with rivaroxaban and 2.4% with warfarin (HR 0.25; 95% CI 0.07 to 0.88).
- Safety
- Major bleeding occurred in 7 patients (1.4%) with rivaroxaban and 13 (2.6%) with warfarin (HR 0.54; 95% CI 0.21 to 1.35). The frequency of other serious adverse events was similar between groups.
- Conclusion
- In patients with atrial fibrillation and a bioprosthetic mitral valve, rivaroxaban was noninferior to warfarin for time to death, major cardiovascular events, or major bleeding at 12 months.
- Why it matters
- It provided randomized evidence that a direct oral anticoagulant is an alternative to vitamin K antagonists in patients with a mitral bioprosthesis, a group in which data were scarce.
Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.
Generated on October 14, 2026