Two-Year Outcomes of Surgical Treatment of Severe Ischemic Mitral Regurgitation.
Michael J. Mack, M.D.
Goldstein, D., A. J. Moskowitz, A. C. Gelijns, G. Ailawadi, M. K. Parides, L. P. Perrault, J. W. Hung, P. Voisine, F. Dagenais, A. M. Gillinov, V. Thourani, M. Argenziano, J. S. Gammie, M. Mack, P. Demers, P. Atluri, E. A. Rose, K. O’Sullivan, D. L. Williams, E. Bagiella, R. E. Michler, R. D. Weisel, M. A. Miller, N. L. Geller, W. C. Taddei-Peters, P. K. Smith, E. Moquete, J. R. Overbey, I. L. Kron, P. T. O’Gara, M. A. Acker, M. Mack, T. A. Settele, N. Settele, W. Ryan, R. L. Smith and P. Grayburn (2016). “Two-Year Outcomes of Surgical Treatment of Severe Ischemic Mitral Regurgitation.” N Engl J Med 374(4): 344-353.
BACKGROUND: In a randomized trial comparing mitral-valve repair with mitral-valve replacement in patients with severe ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI), survival, or adverse events at 1 year after surgery. However, patients in the repair group had significantly more recurrences of moderate or severe mitral regurgitation. We now report the 2-year outcomes of this trial. METHODS: We randomly assigned 251 patients to mitral-valve repair or replacement. Patients were followed for 2 years, and clinical and echocardiographic outcomes were assessed. RESULTS: Among surviving patients, the mean (+/-SD) 2-year LVESVI was 52.6+/-27.7 ml per square meter of body-surface area with mitral-valve repair and 60.6+/-39.0 ml per square meter with mitral-valve replacement (mean changes from baseline, -9.0 ml per square meter and -6.5 ml per square meter, respectively). Two-year mortality was 19.0% in the repair group and 23.2% in the replacement group (hazard ratio in the repair group, 0.79; 95% confidence interval, 0.46 to 1.35; P=0.39). The rank-based assessment of LVESVI at 2 years (incorporating deaths) showed no significant between-group difference (z score=-1.32, P=0.19). The rate of recurrence of moderate or severe mitral regurgitation over 2 years was higher in the repair group than in the replacement group (58.8% vs. 3.8%, P<0.001). There were no significant between-group differences in rates of serious adverse events and overall readmissions, but patients in the repair group had more serious adverse events related to heart failure (P=0.05) and cardiovascular readmissions (P=0.01). On the Minnesota Living with Heart Failure questionnaire, there was a trend toward greater improvement in the replacement group (P=0.07). CONCLUSIONS: In patients undergoing mitral-valve repair or replacement for severe ischemic mitral regurgitation, we observed no significant between-group difference in left ventricular reverse remodeling or survival at 2 years. Mitral regurgitation recurred more frequently in the repair group, resulting in more heart-failure-related adverse events and cardiovascular admissions. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00807040.).