Management of moderate functional mitral regurgitation at the time of aortic valve replacement: Is concomitant mitral valve repair necessary?

Objective: The optimal management of moderate functional mitral regurgitation at the time of aortic valve replacement remains undefined. Methods: We retrospectively identified 686 consecutive patients undergoing aortic valve replacement between 1993 and 2006 with at least moderate (grade 2 or more) functional mitral regurgitation. Patients with structural valve abnormalities or significant coronary artery disease were excluded, leaving 190 in the study. Analyses for predictors of residual mitral regurgitation and survival were performed. The impact of mitral regurgitation on survival was further analyzed among 91 patients case matched for age, gender, and left ventricular ejection fraction to individuals without mitral regurgitation undergoing isolated aortic valve replacement. Results: The mean age of the study group was 74 ± 11years, 45% were male, and 78% had New York Heart Association III or IV Class classification. The mean preoperative ejection fraction was 48% ± 17%. Operative mortality was 5% (n = 9). Follow-up echocardiographic data were available for 88% of patients at discharge and 57% of patients at midterm. Mitral regurgitation was improved at discharge in 76% of patients and at mid-term follow-up in 67% of patients. Independent predictors of improved mitral regurgitation were lesser degrees of preoperative tricuspid regurgitation or prebypass mitral regurgitation, absence of cerebrovascular disease, and lower left ventricular ejection fraction. Postoperatively, 89% of patients were New York Heart Association Class I or II Symptom; No reoperations for mitral regurgitation were performed. Survival was 68% at 5 years and 42% at 10 years. Independent predictors of late mortality were increasing age, diabetes, dialysis-dependent renal failure, and increased tricuspid regurgitation severity. The survival of 91 patients from this cohort did not differ from case-matched patients without mitral regurgitation undergoing aortic valve replacement (P = .33). Conclusion: Moderate functional mitral regurgitation improved in most patients after aortic valve replacement. Residual mitral regurgitation did not affect survival independently of left ventricular function.