What is the preferred anticoagulant, Warfarin (warfarin) or Direct Oral Anticoagulant (DOAC) such as Apixaban (apixaban) or Rivaroxaban (rivaroxaban), for patients with mitral valve disease and an annular prosthetic valve?

Warfarin vs DOACs in Mitral Valve Disease with Annular Prosthetic Valve

Warfarin is the only recommended anticoagulant for patients with mitral valve disease and an annular prosthetic valve, as DOACs are contraindicated in mechanical heart valves and not recommended in moderate-to-severe mitral stenosis. 1

Type of Valve Considerations

Mechanical Valves

• For patients with mechanical mitral valve prostheses:
  • Warfarin is mandatory with a target INR of 3.0 (range 2.5-3.5) 1
  • DOACs are contraindicated and have been shown to increase thromboembolic and bleeding complications compared to warfarin 1
  • The RE-ALIGN trial demonstrated increased harm with dabigatran compared to warfarin in patients with mechanical heart valves 1

Bioprosthetic Valves

• For patients with bioprosthetic mitral valves:
  • Within first 3 months post-implantation: Warfarin with target INR of 2.5 (range 2.0-3.0) 1
  • After 3 months:
    • Without AF: Aspirin 75-100 mg/day is recommended 1, 2
    • With AF: DOACs may be considered if no moderate-to-severe mitral stenosis 1
    • The RIVER trial showed rivaroxaban was non-inferior to warfarin in patients with AF and bioprosthetic mitral valves 3

Mitral Annular Repair (Non-Replacement)

• For patients with mitral valve repair:
  • Anticoagulation recommended for 3 months post-procedure 4
  • Limited evidence suggests rivaroxaban may be safe and effective after mitral valve repair, but larger trials are needed 4

Decision Algorithm Based on Valve Type and Comorbidities

1. Mechanical Mitral Valve

   • ONLY use warfarin (target INR 3.0, range 2.5-3.5)
   • Consider adding low-dose aspirin (75-100 mg/day) for patients with additional risk factors or previous thromboembolism 1

2. Bioprosthetic Mitral Valve

   • First 3 months post-implantation: Warfarin (INR 2.0-3.0)
   • After 3 months:
     • Without AF: Aspirin 75-100 mg/day
     • With AF: Either warfarin or DOACs may be considered (recent evidence supports DOAC use) 3

3. Mitral Valve Repair

   • First 3 months: Anticoagulation required
   • Limited evidence suggests rivaroxaban may be an option 4

Important Monitoring Considerations

• For patients on warfarin:
  • Monitor INR weekly during initiation
  • Monitor at least monthly when stable 1
• For patients on DOACs:
  • Evaluate renal and hepatic function before initiation
  • Reassess at least annually 1

Common Pitfalls to Avoid

1. Misclassifying valve type: Ensure proper distinction between mechanical valves (absolute contraindication to DOACs) and bioprosthetic valves

2. Overlooking mitral stenosis: Even with bioprosthetic valves, moderate-to-severe mitral stenosis is a contraindication to DOACs 1

3. Inadequate INR monitoring: Failure to monitor INR frequently enough during warfarin initiation increases bleeding risk

4. Inappropriate DOAC dosing: Failure to adjust DOAC dosing based on renal function, age, and weight can lead to bleeding complications

The evidence clearly supports warfarin as the only option for mechanical mitral valves, while allowing for consideration of DOACs in specific bioprosthetic valve scenarios without significant mitral stenosis.