Anticoagulation in Patients with Valve Replacement

Introduction to Anticoagulation Guidelines

The American Heart Association recommends that direct oral anticoagulants, including apixaban, should not be used in patients with mechanical valve prostheses (Class III: Harm recommendation) 1, 2, 3
The American College of Cardiology notes that warfarin remains the only approved oral anticoagulant for mechanical heart valves with target INR 2.0-3.0 1, 2, 3, 4

The RE-ALIGN trial was stopped prematurely due to excessive thrombotic complications when dabigatran was compared to warfarin in mechanical valve patients, with stroke occurring in 5% of dabigatran patients versus 0% in warfarin patients, and major bleeding was also significantly higher (4% vs 2%) 1, 2, 3
The FDA has issued a specific contraindication for direct thrombin inhibitors and anti-Xa agents, including apixaban, in patients with mechanical heart valves 1, 2, 3

Patients with atrial fibrillation and bioprosthetic valves (at least 3 months post-implantation) may use apixaban based on subgroup analyses from the ARISTOTLE trial 5
The 2019 AHA/ACC/HRS guidelines note that small numbers of patients with mitral or aortic bioprosthetic valve implants were included in the ARISTOTLE and ENGAGE AF-TIMI 48 trials, suggesting apixaban and edoxaban appeared to be equitable alternatives to warfarin in patients with remote bioprosthetic valve implantation 5

The American Heart Association recommends that DOACs, including apixaban, are specifically contraindicated in patients with moderate-to-severe mitral stenosis, which is common in rheumatic heart disease 6, 7
Bioprosthetic valves implanted via TAVR have not been adequately studied with apixaban, and the standard post-TAVR regimen is dual antiplatelet therapy (aspirin plus clopidogrel) for 6 months, not DOACs 2, 3