Redo-mitral valve replacement and predictors of operative mortality: a single-institute experience

Abstract

Background In spite of improved survival of first-time mitral valve replacement (MVR), operative mortality associated with redo-mitral valve surgery is still higher than that of the primary operation. Consequently, more patients require redo-MVR, and studies investigating the operative outcome with current techniques and prostheses are thus needed. Patients and methods This is a nonrandomized prospective study that included 83 patients who underwent redo-MVR with either bioprosthetic or mechanical valves between March 2014 and December 2017 at National Heart Institute. Recorded data were analyzed using the statistical package for social sciences, version 23.0 (IBM SPSS). All preoperative and operative data were analyzed in univariate model to identify predictors of operative mortality and prolonged hospital stay (more than 10 days). Results A total of 46 (55.4%) females and 37 (44.5%) males constituted the study population. Overall, 16 (19.3%) patients in this study had ejection fraction below 50%. Indications for reoperation included endocarditis in 38 (45.8%) patients, para-prosthetic leak in 23 (27.7%) patients, structural valve degeneration in 12 (14.4%) patients, and prosthetic valve thrombosis in 10 (12.0%) patients. In-hospital mortality was 11 (13.3%) patients. Mean hospital stay was 13.68 ± 3.87 days (range, 7–22 days). Univariate analysis showed that operative mortality was associated with the left ventricular ejection fraction less than 50% (P = 0.018), structural valve degeneration (P = 0.027), and total operative time in hours (P < 0.001). Similarly, univariate analysis for prolonged hospital stay showed a significant association between it and higher preoperative EuroSCORE (P = 0.003). Conclusion Repeat MVR can be done safely and with a good overall clinical outcome. Although left ventricular ejection fraction less than 50%, structural valve degeneration, and total operative time in hours are associated with early hospital mortality, higher preoperative EuroSCORE is associated with prolonged hospital stay.