Impact of reoperation on very long-term survival in patients with failed mitral valve repair: A 30-year single-center Canadian experience.

Abstract

To evaluate the incidence, mechanisms, and timing of recurrent mitral regurgitation (MR) requiring reoperation after degenerative mitral valve repair (MVr) and to assess its impact on long-term survival and cardiovascular readmissions in a large single-center cohort with more than 3 decades of follow-up. All MVr procedures performed between January 1991 and May 2024 were reviewed (n = 2383). After we excluded patients with nonmyxomatous etiologies, who had previous mitral surgery, with nonrepair procedures, and with associated major interventions, 1222 patients with isolated degenerative MR comprised the final cohort. Outcomes were obtained from a provincial administrative database. The primary end point was reoperation for recurrent MR; secondary end points included long-term survival and cardiovascular readmissions. Multivariable analyses used Cox-based approaches and generalized linear models. Reoperation occurred in 82 patients (6.7%). Early failures (<1 year) represented 35.4% and were predominantly technical (62% of early failures), whereas late failures (≥1 year) accounted for 64.6% and were mainly driven by disease progression (35.9% of late failures) or fibrosis (32.1%). Freedom from reoperation was 97.6% at 1 year, 94.9% at 5 years, and 88.2% at 20 years. Residual MR ≥2+ at discharge was the strongest predictor of reoperation (hazard ratio [HR], 7.53; 95% CI, 4.76-11.90; P < .0001) and of early dysfunction (HR, 10.90; P < .0001). Long-term survival did not differ between reoperated and nonreoperated patients (HR, 1.18; 95% CI, 0.75-1.86; P = .49). Cardiovascular readmissions were significantly more frequent before reoperation, with an annualized rate of 0.17 events per patient-year compared with 0.07 after reoperation; this reduction was highly significant (P < .0001 by Poisson regression). In a highly specialized mitral repair program, reoperation for recurrent MR is uncommon and does not negatively affect long-term survival. Residual MR at discharge is the principal determinant of repair failure, and timely reoperation restores clinical stability and substantially reduces cardiovascular morbidity.