Minimally Invasive Versus Sternotomy in Redo Mitral Valve Surgery: Short‐ and Long‐Term Outcomes with Meta‐Regression and Time‐to‐Event Analysis

Background Redo mitral valve surgery carries substantial risk, and the relative benefits of minimally invasive (MI‐MVS) versus sternotomy MVS, particularly regarding long‐term survival, remain uncertain. Methods Electronic databases were searched for studies comparing MI‐MVS with sternotomy MVS in adult redo MVS. Kaplan–Meier curves were digitized to reconstruct individual patient data for time‐to‐event analysis, with study‐level hazard ratios (HR) generated using a Cox frailty model. Perioperative outcomes were pooled using random‐effects models. Subgroup analyses evaluated propensity‐matched cohorts, endoscopic/video‐assisted minithoracotomy, and direct‐vision minithoracotomy. Meta‐regression explored the impact of study‐level covariates on mortality. Results Fifteen studies including 3457 patients were analyzed. MI‐MVS was associated with lower perioperative mortality compared with sternotomy MVS (odds ratio [OR], 0.33 [95% CI, 0.23–0.48]; P <0.001), reduced incidence of reoperation (OR, 0.65 [95% CI, 0.44–0.98]; P =0.04), and acute kidney injury (OR, 0.58 [95% CI, 0.39–0.87]; P =0.008); rates of stroke and arrhythmia were similar. The direction and magnitude of the mortality effect consistently favored MI‐MVS in the subgroup analyses. Time‐to‐event analysis demonstrated improved survival with MI‐MVS (HR, 0.74 [95% CI, 0.62–0.89]; P =0.001), but this was attenuated in the propensity‐matched analysis. Meta‐regression showed that sex distribution, mean age, and baseline left ventricular ejection fraction did not significantly moderate mortality effects. Conclusions In redo MVS, MI‐MVS is associated with improved perioperative outcomes without compromising long‐term survival; however, attenuation of the survival difference after propensity matching suggests that this long‐term advantage may reflect baseline risk rather than procedural effect.