What antithrombotic therapy is recommended for patients receiving a bioprosthetic aortic or mitral valve replacement?
During the first 3 months after bioprosthetic valve implantation, aspirin is recommended for aortic valves; the combination of aspirin and clopidogrel is recommended if the aortic valve is transcatheter; and vitamin K antagonist therapy with a target INR of 2.5 is recommended for mitral valves. After 3 months, aspirin is recommended according to ACC/AHA guidelines for the management of patients with valvular heart disease. Warfarin (INR, 2.0 to 3.0) is recommended after aortic valve replacement with bileaflet mechanical or Medtronic Hall prostheses in patients with no risk factors, while warfarin (INR, 2.5 to 3.5) is recommended in patients with risk factors. Warfarin (INR, 2.5 to 3.5) is also recommended after mitral valve replacement with any mechanical valve and the addition of low-dose aspirin to warfarin is recommended for all patients with mechanical valves.