Rivaroxaban Is Effective in Patients With Bioprosthetic Mitral Valve

Rivaroxaban is comparable to warfarin for treating patients with bioprosthetic mitral valves and atrial fibrillation or flutter, according to the results of a new study presented at the 2020 American Heart Association’s Scientific Sessions.1 Warfarin is the current standard of care for patients with bioprosthetic mitral valves.

To better understand the safety and efficacy of this alternative treatment option, the researchers conducted the Rivaroxaban for Valvular Heart Disease and Atrial Fibrillation trial (RIVER), a noninferiority, multicenter, open-label, randomized trial.

Included in the study were 1005 patients with a bioprosthetic mitral valve and atrial fibrillation or flutter for 12 months. Participants were from 49 sites throughout Brazil.

The participants were randomly assigned to 1 of 2 groups: (1) a single-dose of rivaroxaban, 20 mg daily, (or for participants with renal dysfunction, 15 mg once daily), or (2) warfarin with doses titrated to maintain a target International Normalized Ratio (INR) of 2.0 to 3.0.

After 12 months of follow-up, the results indicated that patients who received rivaroxaban had an average of 347.5 days free from primary outcomes, including:

  • All-cause mortality
  • Stroke
  • Transient ischemic attack
  • Major bleeding
  • Valve thrombosis
  • Systematic embolism that was not related to the central nervous system
  • Hospitalization for heart failure

This result is similar among participants treated with warfarin (340.1 days). In a subgroup analysis, 18.8% of RIVER participants showed a mean of 35.1 days longer without evidence of the primary outcomes compared with participants who took warfarin within the prior 3 months.

“The results from the RIVER Trial are consistent with previous research, including ROCKET and other pivotal trials of DOACs, and can inform clinical practice for patients with bioprosthetic mitral valves,” lead study author Otavio Berwanger said in a press release.2 “For a subgroup of patients with a mitral valve replacement within the last three months, rivaroxaban was statistically and clinically superior to warfarin.”


—Leigh Precopio



  1. Berwanger O, Lopes RD, Silva PG, et al. Rivaroxaban versus warfarin in patients with bioprosthetic mitral valves and atrial fibrillation or flutter: primary results from the RIVER randomized trial. Paper presented at: American Heart Association Scientific Sessions 2020; November 13-17, 2020; Virtual.!/9144/presentation/41899
  2. Rivaroxaban may be as effective as warfarin for bioprosthetic mitral valves, AF. News release. American Heart Association. November 14, 2020. Accessed November 20, 2020.