Myocardial Trauma in Cardiopulmonary Bypass: Mechanisms and Clinical Implications.

This paper mainly addresses trauma inflicted on the myocardium and associated cardiac structures during procedures which require perfusion. Perfusion-related myocardial trauma is a significant concern during cardiac surgical procedures that require cardiopulmonary bypass (CPB). This review examines the mechanisms of myocardial and vascular injury associated with key perfusion procedures, including aortic, venous, and femoral cannulation, initiation of CPB, aortic cross-clamping, cardioplegia delivery, deairing, and reperfusion. Specific surgical procedures such as coronary artery bypass grafting (CABG), valve replacement, aortic root repair, ventricular assist device (VAD) insertion, and heart transplantation are also discussed in relation to myocardial trauma. Additionally, post-perfusion and weaning-related injuries, including microvascular dysfunction, oxidative stress, inflammatory responses, and residual wall stress, are reviewed. Understanding these mechanisms is essential for improving myocardial protection strategies and patient outcomes.