Is short-term anticoagulation necessary after mitral valve repair?

Abstract

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether oral anticoagulants are necessary after mitral valve repair. The reported search found 127 papers of which 12 represented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group, relevant outcomes and weaknesses were tabulated. We conclude that the current European Society of Cardiology guidelines support the use of warfarin for 3 months post-mitral repair, citing an absence of studies supporting the safety of omitting warfarin. They acknowledge that this is based on expert consensus and that many surgeons do not follow this guideline. No other guidelines provide recommendations in this area. The longest follow-up studies of patients post-mitral repair report excellent results using short term warfarin, and they also show that a third of patients discharged in sinus rhythm will have an episode of atrial fibrillation shortly after. In addition, the highest risk of thromboembolism occurs in the early months post surgery. Therefore, until studies demonstrate the safety of omitting warfarin for patients undergoing mitral valve repair, 3 months of anticoagulation should remain the standard of care.