Which antithrombotic strategy provides the best outcomes after mitral valve repair in patients who remain in sinus rhythm?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was ‘in the first 3-months after mitral valve repair (MVRep) which antiplatelet and/or anticoagulant strategy should be instigated in patients who remain in normal sinus rhythm’. Altogether 77 papers were found using the reported search, of which 8 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that there remains a lack of high-quality randomized studies, controlling for postoperative cardiac rhythm, comparing vitamin K antagonists (VKA) and antiplatelet therapy in the early postoperative period following isolated MVRep. Current guidelines are based on limited evidence or expert consensus alone. Based on the currently available evidence, the authors conclude that antiplatelet therapy (e.g. aspirin) is safe and appropriate to use in the 3-month postoperative period following isolated MVRep, in those without preoperative, or postoperative atrial fibrillation. Rates of thromboembolic events are comparable between these patient groups (i.e. VKA versus aspirin), whilst VKA therapy is associated with increased rates of major bleeding events and mortality.