Long-Term Outcomes of the Maze Procedure Combined With Mitral Valve Repair: Risk of Thromboembolism Without Anticoagulation Therapy.

Abstract

Although the strongest benefit of a concomitant Maze procedure during mitral valve repair is the obviation of the need for anticoagulation therapy, the risk of thromboembolism without anticoagulation therapy has not been evaluated. A total of 362 consecutive patients (aged 52.2 ± 13.8 years, 180 females) who underwent the Maze procedure combined with mitral valve repair between 1997 and 2012 were evaluated. Anticoagulation therapy was discontinued after 6 months if synchronous atrial contraction was maintained in the absence of further risks of thromboembolism. The median follow-up period was 5.4 years (interquartile range, 2.9 to 9.6 years). Late atrial fibrillation (AF) occurred in 62 patients (17.1%). The 5-year freedom from AF off anti-arrhythmic drugs was 82.6% ± 2.3%. In 96 patients (26.5%), warfarin was administered in the late period (>6 months), and of them, 54 patients (14.9%) were maintained with warfarin therapy until the end of the follow-up. Patients receiving warfarin therapy were older (p = 0.030), had longer AF duration (p = 0.012), and had rheumatic valvulopathy more frequently (p = 0.003) compared with those not receiving warfarin. Overall, patients were followed up off the warfarin therapy for 1,577 patient-years, during which there were 4 cases of stroke or transient ischemic accident and 21 late deaths. The linearized rates of thromboembolic event and death without warfarin therapy were 0.06% and 0.12% per patient-year, respectively, and these rates were not significantly different from those receiving warfarin therapy. Adopting appropriate selection criteria for discontinuing anticoagulation therapy, the majority of patients receiving concomitant mitral repair and the Maze procedure can discontinue warfarin with excellent long-term safety profiles.