Impact of Prosthesis-Patient Mismatch After Surgical Mitral Valve Replacement: Systematic Review and Meta-Analysis.

The long-term clinical impact of mitral prosthesis-patient mismatch (PPM) after mitral valve replacement (MVR) remains incompletely defined. We aimed to systematically assess the prevalence of mitral PPM and its association with long-term mortality, cardiac death, and heart failure-related hospitalizations. We conducted a systematic review and meta-analysis of observational studies reporting Kaplan-Meier time-to-event data in patients with and without mitral PPM. Sixteen studies, including 10,872 patients, were analyzed. The pooled prevalence of any mitral PPM was 43% (95% confidence interval [CI], 29% to 59%), with significant heterogeneity (I² = 100%). All-cause mortality was higher with PPM (hazard ratio [HR], 1.32; 95% CI, 1.20 to 1.45; p < 0.001; RMST difference, -3.35 years; 95% CI, -3.98 to -2.71; p < 0.001), as was cardiac mortality (HR, 1.96; 95% CI, 1.54 to 2.51; p < 0.001) and risk of heart failure hospitalization (HR, 2.82; 95% CI, 1.86 to 4.29; p < 0.001). Risk-adjusted analyses confirmed these associations for all-cause and cardiac mortality. Severity-stratified analyses demonstrated a gradient effect: moderate PPM showed a trend toward higher mortality (HR, 1.12; 95% CI, 0.98 to 1.27; p = 0.08), whereas severe PPM significantly increased mortality risk (HR, 1.36; 95% CI, 1.15 to 1.60; p < 0.001). Sensitivity analyses according to PPM quantification method (in vivo vs Doppler) and leave-one-out testing confirmed the robustness of the results. In conclusion, mitral PPM is common and independently associated with increased long-term all-cause mortality, cardiac death, and heart failure hospitalizations after MVR, with a dose-response relationship according to PPM severity. These findings highlight the importance of preventive strategies to avoid PPM when planning MVR.