Perioperative Myocardial Protection in Adult Cardiac Surgery: Critical Gaps in Current Strategies and Perspectives for Clinical Practice

Myocardial protection during cardiac surgery is critical for preserving cardiac function, minimizing ischemia-reperfusion injury, and preventing myocardial stunning. Although advances in cardioplegia formulations, delivery techniques, pharmacologic agents, and controlled reperfusion strategies have entered clinical practice, substantial variability in protocols and limited comparative evidence continue to hinder optimization and standardization. This narrative review is aimed at highlighting critical current evidence, identifying key gaps in perioperative myocardial protection, and discussing emerging opportunities for innovation and personalized strategies. A comprehensive literature search was conducted in PubMed and Embase through June 2025, with a combination of MeSH terms and keywords related to cardioplegia and myocardial protection. High-quality studies, including randomized trials, systematic reviews, and authoritative expert opinions, were selected according to relevance to key themes, including cardioplegia types, delivery techniques, risk populations, pharmacologic adjuncts, and real-time monitoring technologies. No cardioplegia strategy is universally accepted, and cardioplegic formulation composition, temperature, and delivery methods widely vary across institutions. Although modified del Nido solutions have gained popularity, comparative evidence remains inconsistent. Small volume cardioplegia solutions (e.g., Cardioplexol®) show future promise. High-risk populations, such as those with diabetes or left ventricular hypertrophy, continue to experience suboptimal outcomes, probably because of distinct metabolic and structural vulnerabilities. Pharmacologic agents mimicking ischemic preconditioning have achieved limited translation into routine practice, and remote ischemic conditioning remains underused, owing to inconsistent evidence. Real-time intraoperative monitoring of myocardial injury and established threshold values for early myocardial injury biomarkers are notably lacking. Emerging modalities such as intramyocardial pH sensors and coronary sinus metabolite sampling offer promise for early injury detection but are far from achieving widespread use. Substantial gaps persist in the personalization and standardization of myocardial protection in cardiac surgery. Innovative approaches are required to advance intraoperative sensing technologies and adjunct protective interventions tailored to patient risk profiles. Incorporating artificial intelligence, leveraging omics data, and fostering multi-institutional collaboration are key steps toward a new era of precision myocardial protection.