Myocardial Injury After Transcatheter Mitral Valve Replacement Versus Surgical Reoperation

This study aimed to evaluate the incidence and clinical implications of myocardial injury, as determined by cardiac biomarker increase, in patients who underwent mitral bioprosthesis dysfunction treatment with transcatheter mitral valve replacement (TMVR) versus surgical mitral valve replacement reoperation (SMVR-REDO). Between 2014 and 2023, 310 patients with mitral bioprosthesis failure were included (90 and 220 patients for TMVR and SMVR-REDO, respectively). Multivariable analysis and propensity score matching were performed to adjust for the intergroup differences in baseline characteristics. Creatinine kinase-MB (CK-MB) and cardiac troponin I (cTn) were collected at baseline and 6 to 12, 24, 48, and 72 hours after intervention. The cardiac biomarkers values were evaluated in relation to their reference values. The outcomes were determined according to the Mitral Valve Academic Research Consortium criteria. CK-MB and cTn increased above the reference level in almost all patients after SMVR-REDO and TMVR (100% vs 94%, respectively), with the peak occurring within 6 to 12 hours. SMVR-REDO was associated with a two- to threefold higher increase in cardiac biomarkers. After 30 days, the mortality rates were 13.3% in the TMVR and 16.8% in the SMVR-REDO groups. At a median follow-up of 19 months, the mortality rates were 21.1% in the TMVR and 17.7% in the SMVR-REDO groups. Left ventricular ejection fraction, estimated glomerular filtration rate, CK-MB, and cTn were predictors of mortality. In conclusion, some degree of myocardial injury occurred systematically after the treatment of mitral bioprosthetic degeneration, especially after SMVR, and higher CK-MB and cTn levels were associated with increased cumulative late mortality, regardless of the approach.