Antithrombotic Therapy Recommendations for Antithrombotic Therapy for Prosthetic Valves Referenced studies that support the recommendations are summarized in Online Data Supplement 36. COR LOE Recommendations In patients with a mechanical prosthetic valve, anticoagulation with a VKA is For patients with a mechanical bileaflet or current-generation single-tilting disk AVR and no risk factors for thromboembolism, anticoagulation with a VKA to achieve an INR For patients with a mechanical AVR and additional risk factors for thromboembolism (eg, AF, previous thromboembolism, LV dysfunction, hypercoagulable state) or an older-generation prosthesis (eg, ball-in-cage), anticoagulation with a VKA is indicated to achieve an INR of 3.0.9,10 For patients with a mechanical mitral valve replacement, anticoagulation with a VKA is indicated to achieve an INR of 3.0.9,11 For patients with a bioprosthetic TAVI, aspirin 75 to 100 mg daily is reasonable in the absence of other indications for oral For all patients with a bioprosthetic SAVR or mitral valve replacement, aspirin 75 to 100 mg daily is reasonable in the absence of other indications for oral anticoagulants.9,15 18 For patients with a bioprosthetic SAVR or mitral valve replacement who are at low risk of bleeding, anticoagulation with a VKA to achieve an INR of 2.5 is reasonable for at least 3 months and for as long as 6 months after surgical replacement.15,19 25 For patients with a mechanical SAVR or mitral valve replacement who are managed with a VKA and have an indication for antiplatelet therapy, addition of aspirin 75 to 100 mg daily may be considered when the risk of bleeding is low.26 For patients with a mechanical On-X AVR and no thromboembolic risk factors, use of a VKA targeted to a lower INR (1.5 2.0) may be reasonable starting 3 months after surgery, with continuation of aspirin 75 to 100 mg For patients with a bioprosthetic TAVI who are at low risk of bleeding, dual- antiplatelet therapy with aspirin 75 to 100 mg and clopidogrel 75 mg may be reasonable for 3 to 6 months after valve For patients with a bioprosthetic TAVI who are at low risk of bleeding, anticoagulation with a VKA to achieve an INR of 2.5 may be reasonable for at least 3 months after valve 3: Harm B-R For patients with bioprosthetic TAVI, treatment with low-dose rivaroxaban (10 mg daily) plus aspirin (75 100 mg) is contraindicated in the absence of other indications for oral anticoagulants.30 3: Harm B-R For patients with a mechanical valve prosthesis, anticoagulation with the direct thrombin inhibitor, dabigatran, is 3: Harm C-EO For patients with a mechanical valve prosthesis, the use of anti-Xa direct oral anticoagulants has not been assessed and is Synopsis Antithrombotic therapy after prosthetic valve implanta- tion is provided to prevent valve/leaflet thrombosis and reduce the incidence of thromboembolic complications. 