Outcome of del Nido versus St. Thomas cardioplegia solution in adult mitral valve replacement surgery for rheumatic mitral valve disease

Background Effective myocardial protection is essential for successful outcomes in open-heart surgery. Although both del Nido and St. Thomas cardioplegia solutions are widely used, comparative evidence in adult rheumatic mitral valve replacement remains limited. This study aimed to compare their myocardial protective efficacy and clinical outcomes. Methods A prospective comparative study was conducted between May 2022 and October 2024. Total 50 adult patients undergoing mitral valve replacement—20 with severe mitral regurgitation (MR) and 30 with severe mitral stenosis (MS) were included. Patients were divided into two groups based on cardioplegia type (del Nido or St. Thomas). Intraoperative parameters, postoperative left ventricular ejection fraction (LVEF), troponin I levels, inotropic and ventilatory support, and ICU/hospital stay were analysed. Results Baseline characteristics were comparable across groups. The mean number of cardioplegia doses was significantly lower in the del Nido group (1.6 ± 0.5 vs 3.2 ± 0.8; p < 0.001). Postoperative LVEF was better preserved with del Nido cardioplegia (MS: 53.3 ± 7.2% vs 45.3 ± 10.6%; p = 0.023). Troponin I levels at 6, 24, and 48 h were lower in the del Nido group, though not statistically significant. Patients receiving del Nido required less inotropic and ventilatory support, with shorter ICU and hospital stays. One in-hospital death occurred in the del Nido group due to sepsis. Conclusion Del Nido cardioplegia offers comparable or superior myocardial protection to St. Thomas solution in adult mitral valve replacement, with fewer interruptions, reduced dosing, and faster postoperative recovery.