Mitral valve repair versus replacement for degenerative mitral regurgitation in patients with poor ejection fraction: A 20-year propensity-score matched analysis of early postoperative outcomes.

ObjectivesTo compare early postoperative outcomes between mitral valve repair (MVr) and replacement (MVR) in patients with degenerative mitral valve disease (DMVD) and poor preoperative left ventricular ejection fraction (LVEF).MethodsA retrospective propensity-score matched analysis of 1,138 patients (612 MVr, 526 MVR) undergoing mitral valve surgery for DMVD with LVEF <30% between 2000-2019 was undertaken using the UK National Adult Cardiac Surgery Audit. The primary outcome was in-hospital mortality; secondary outcomes included stroke, postoperative dialysis, re-exploration for bleeding and length of stay >10 days. Binary logistic regression was conducted to further examine the relationship between procedure and outcomes.ResultsIn unadjusted analyses, MVr demonstrated lower in-hospital mortality (7.2% vs 17.1%, p < 0.001), postoperative dialysis (7.2% vs 14.1%, p < 0.001), and prolonged hospital stay (54.5% vs 67.1%, p < 0.001). After propensity matching, unadjusted outcomes continued to favour MVr for mortality (8.5% vs 13.0%, p = 0.040) and dialysis (8.3% vs 12.8%, p = 0.038). However, multivariable adjustment demonstrated no significant difference in mortality (OR = 0.64, 95% CI 0.39-1.05, p = 0.080) or major morbidity between techniques. Independent predictors of mortality included emergency surgery, concomitant aortic valve surgery, peripheral vascular disease, and redo sternotomy.ConclusionsIn patients with DMVD and severely reduced LVEF, MVr demonstrated comparable early mortality and morbidity to MVR after adjustment. These findings suggest that mitral valve repair is safe and feasible in this higher-risk population when appropriate surgical expertise and careful patient selection are applied. Further investigation with larger cohorts and long-term follow-up is needed to assess durability and functional outcomes.