Apixaban Must Be Discontinued and Should Never Be Used in Patients with Mechanical Aortic Valves
Apixaban is absolutely contraindicated in patients with mechanical aortic valve prostheses and must be discontinued immediately—these patients require lifelong warfarin therapy with no acceptable alternatives. 1, 2, 3
Critical Safety Issue: Apixaban is Contraindicated
The FDA and ACC/AHA guidelines explicitly state that direct oral anticoagulants, including apixaban, are contraindicated (Class III: Harm) in all patients with mechanical heart valves. 1, 2, 3, 4
The 2023 PROACT Xa trial definitively demonstrated that apixaban is inferior to warfarin in patients with On-X mechanical aortic valves, with thromboembolic event rates of 4.2%/patient-year with apixaban versus 1.3%/patient-year with warfarin—the trial was stopped early due to excess thromboembolic events in the apixaban group. 5
This patient should never have been on apixaban in the first place—mechanical valves require warfarin, period. 2, 6
Immediate Management for Dental Surgery
For dental procedures where bleeding is easily controlled (such as dental extractions), continuation of warfarin anticoagulation with therapeutic INR is the recommended approach—do not stop the warfarin. 1
Step-by-Step Approach:
Immediately transition the patient from apixaban to warfarin if not already done, as apixaban provides inadequate protection against valve thrombosis. 2, 3, 5
For the dental surgery itself, continue warfarin without interruption if the procedure involves simple extractions, dental cleaning, or treatment where bleeding can be easily controlled with local measures. 1
Target INR should be 2.5 (range 2.0-3.0) for a mechanical aortic valve without additional risk factors, or INR 3.0 (range 2.5-3.5) if the patient has atrial fibrillation, prior thromboembolism, LV dysfunction, hypercoagulable state, or an older-generation valve. 1, 2
Coordinate with the dentist to ensure local hemostatic measures are available (sutures, hemostatic agents, pressure). 1
When Warfarin Interruption Might Be Considered
If the dental procedure is more extensive and carries higher bleeding risk, temporary interruption of warfarin without bridging therapy is acceptable only for patients with a bileaflet mechanical aortic valve and no other thromboembolic risk factors. 1
Stop warfarin 2-4 days before the procedure to allow INR to fall below 2.0. 1
Do not use bridging anticoagulation with heparin or LMWH in low-risk patients (bileaflet aortic valve, no AF, no prior thromboembolism). 1
Resume warfarin within 24 hours after the procedure once bleeding risk allows. 1
Critical Pitfalls to Avoid
Never continue apixaban perioperatively in a patient with a mechanical valve—it provides inadequate thromboprophylaxis even when not interrupted. 5
Do not assume all dental procedures require anticoagulation interruption—most routine dental work can be performed safely with therapeutic INR. 1
Bridging anticoagulation for mechanical aortic valves has been downgraded from Class I to Class IIa based on evidence showing increased bleeding without clear benefit in lower-risk patients, so avoid routine bridging in patients with isolated mechanical aortic valves without additional risk factors. 1
If the patient has additional risk factors (mechanical mitral valve, AF, prior thromboembolism, older-generation valve), bridging with LMWH or unfractionated heparin becomes reasonable when warfarin must be interrupted. 1
Bottom Line Algorithm
Is the patient currently on apixaban? → Transition to warfarin immediately (this is a medication error). 2, 3, 5
Is the dental procedure minor with easily controlled bleeding? → Continue warfarin at therapeutic INR. 1
Is the procedure higher risk AND patient has isolated bileaflet aortic valve with no other risk factors? → Stop warfarin 2-4 days before, no bridging, resume within 24 hours. 1
Does the patient have additional thromboembolic risk factors? → Consider bridging anticoagulation if warfarin must be stopped. 1