Myocardial Protection During Surgery for Infective Endocarditis: Retrospective Analysis and Rationale for Randomized Trial

All articles of this category (opens in new window) Background: Current evidence does not support the definitive superiority of one cardioplegia type over another in terms of mortality or major morbidity. However, these findings are largely derived from studies in general cardiac surgical populations with moderate risk profiles. In contrast, patients undergoing surgery for infective endocarditis (IE) are usually multimorbid and frequently hemodynamically unstable, often presenting at an advanced age—factors that may amplify systemic effects of cardioplegia, such as vasoplegia, renal dysfunction, or stroke. This retrospective single-center, risk-adjusted study aimed to assess whether the type of cardioplegia influences outcomes in this high-risk population. Methods: We analyzed 553 patients who underwent high-risk (mean EuroScore II: 22.7) surgery for IE between 2009 and 2023 and received either cold crystalloid (Custodiol, n = 335) or warm blood (Calafiore, n = 218) cardioplegia. The primary endpoint was 1-year mortality. Secondary endpoints included 30-day mortality, postoperative stroke, and new-onset dialysis. Propensity score matching (1:1, 14 covariates) resulted in 175 matched pairs. Statistical analysis included nonparametric and exact tests. Results: The patient population was high-risk with a mean EuroScore II: 22.7. In the matched cohort, mortality at 1 year was 37.1% with Custodiol and 28.6% with Calafiore ( p = 0.09). Thirty-day mortality was 22.9% and 14.9% ( p = 0.057), and dialysis rates were 20.6% and 13.7% ( p = 0.091) with Custodiol and Calafiore, respectively. Stroke incidence was lower in the overall matched cohort for the Calafiore group (10.9% vs. 4.6%, p = 0.029). In the matched cohort, numerical differences in mortality favored Calafiore, but these differences lost consistency when stratified by procedure type: aortic valve 25.3% vs. 23.0% ( p = 0.727), mitral valve 47.1% vs. 20.6% ( p = 0.024), double valve 48.8% vs. 44.2% ( p = 0.673). This suggests that the apparent effect in the overall cohort was largely driven by heterogeneity of surgical case distribution rather than by the cardioplegia strategy itself. Conclusion: In this high-risk cohort of infective endocarditis surgery, no clear superiority of Custodiol or Calafiore cardioplegia could be demonstrated for 1-year mortality. Across overall comparisons, numerical advantages (reduced dialysis rates, lower stroke incidence, and shorter ICU stay) consistently favored warm blood cardioplegia, possibly reflecting systemic effects. These trends did not translate into consistent survival benefits but underline the need for a prospective randomized trial. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany