In Anticoagulation After Mechanical Aortic-Valve Replacement, How Low Can You Go?

Mechanical aortic valves have the benefit of greater longevity but are associated with the burden and risk of lifelong anticoagulation. In an industry-funded study, researchers examined outcomes (bleeding, thromboembolism, and valve thrombosis) with various anticoagulation therapies in patients with the FDA-approved On-X bileaflet mechanical heart valve (NCT00291525), which was developed to require less intense anticoagulation. All patients initially received standard warfarin therapy (target international normalized ratio [INR], 2.0–3.0) plus 81-mg aspirin.

At 3 months postimplantation, 201 patients at low thromboembolism risk were randomized to dual antiplatelet therapy (DAPT; 75-mg clopidogrel and 325-mg aspirin) or standard warfarin/aspi…