Consistent treatment effect of DOAC regardless of valvular heart disease etiology and event risk

Rivaroxaban versus Warfarin in Patients with Bioprosthetic Valves According to Valvular Heart Disease Etiology, and Thrombotic and Bleeding Risks: Insights from the RIVER Randomized Trial

Presented at the ESC Congress 2023 by: Pedro de Barros e Silva, MD - Sao Paulo, Brazil

Introduction and methods

The RIVER trial previously showed that rivaroxaban was noninferior to warfarin for the primary outcome of death, major CV events, or major bleeding at 12 months in patients with atrial fibrillation and a bioprosthetic mitral valve. The current analysis of the RIVER trial evaluated whether the results varied according to thromboembolic and bleeding risk and according to valvular heart disease etiology (rheumatic vs. non-rheumatic).

RIVER was a randomized, open-label, noninferiority trial. A total of 1005 patients with atrial fibrillation or flutter and a bioprosthetic mitral valve were randomized to treatment with either rivaroxaban 20 mg (15 mg for CR Cl 30-49 ml/min) daily or warfarin (INR target 2.0-3.0) for 12 months. The primary endpoint was as composite of death, major CV events, or major bleeding.

Main results

• The results of the RIVER trial did not change according to the risk of bleeding and according to the thromboembolic risk.
• The event rates were similar between patients with rheumatic and non-rheumatic valvular heart disease. There was no interaction according to the valvular heart disease etiology for the primary composite endpoint and all individual components.

Conclusion

This analysis of the RIVER trial showed that among patients with atrial fibrillation or flutter and a bioprosthetic mitral valve, patients with rheumatic heart disease did not have an increased risk of thrombotic and bleeding events. “The treatment effect of rivaroxaban versus warfarin was consistent regardless of valvular heart disease etiology and risk of events” said Pedro de Barros e Silva.

- Our reporting is based on the information provided at the ESC Congress 2023 -