This 20-year propensity-matched study, utilizing data from the UK National Adult Cardiac Surgery Audit, examined whether mitral valve repair (MVr) offers better early outcomes than replacement (MVR) in patients with degenerative disease and severely impaired left ventricular (LV) function (left ventricular ejection fraction (LVEF)<30 percent).
Analyzing 1,138 patients (612 MVr vs 526 MVR), both unadjusted and propensity-matched comparisons found that MVr was associated with lower rates of in-hospital mortality, postoperative dialysis requirement, and prolonged length of stay. However, after multivariable adjustment, the mortality difference between techniques no longer showed statistical significance (OR 0.64, 95 percent CI 0.39–1.05), as did major morbidity outcomes. Independent predictors of in-hospital mortality included emergency surgery, concomitant aortic valve surgery, peripheral vascular disease, and redo sternotomy.
The authors conclude that MVr is safe and feasible even in this high-risk population, provided there is appropriate expertise and patient selection are applied; however, longer-term durability and functional data are still needed to definitively demonstrate superiority of a particular approach.
