According to ACC/AHA 2021 guidelines, the preferred anticoagulation for a patient with a mechanical mitral valve prosthesis is:

• A Direct oral anticoagulants (DOACs) at full therapeutic dose
• B Aspirin alone in low-risk patients
• C Heparin bridging long-term without warfarin
• D Vitamin K antagonist (warfarin) with INR target 2.5–3.5 ✓

Explanation

Mechanical prosthetic valves require lifelong warfarin anticoagulation — DOACs are CONTRAINDICATED for mechanical valves (RE-ALIGN trial showed increased thromboembolic events and bleeding with dabigatran vs warfarin in mechanical valve patients). For mechanical mitral valve: INR target 2.5–3.5 (higher-risk position vs aortic valve at 2.0–3.0). Aspirin alone is grossly inadequate, though low-dose aspirin 75–100 mg is added to warfarin in high-risk patients. Heparin bridging is perioperative only.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.