Vasoplegia in Cardiac Surgery and Mechanical Circulatory Support: From Cardiopulmonary Bypass to Advanced Circulatory Support Devices.

Vasoplegia remains one of the most challenging and incompletely understood complications across the spectrum of mechanical circulatory support (MCS). Initially described following cardiopulmonary bypass, it is increasingly recognized in patients supported with veno-arterial extracorporeal membrane oxygenation (V-A ECMO) and combined unloading strategies such as ECPELLA (ECMO and Impella support) as well as in patients bridged to heart transplantation with temporary or durable mechanical circulatory support (MCS). Despite occurring in different clinical settings, these syndromes share common pathophysiological features, including systemic inflammation, endothelial dysfunction, glycocalyx degradation, dysregulated nitric oxide signaling, neurohormonal imbalance, microcirculatory impairment and severe vasomotor dysregulation. Although vasoplegia is commonly considered a technology-specific complication, growing evidence suggests that CPB-associated vasoplegia, postcardiotomy vasoplegic syndrome, ECMO-related vasodilatory shock and distributive shock during ECPELLA may represent distinct manifestations of a common pathobiological process driven by blood-artificial surface interactions, ischemia-reperfusion injury, hemolysis and immune activation. This narrative review proposes a unified framework of vasoplegia across the continuum of MCS. Key mechanistic pathways and current therapeutic strategies, including catecholamines, vasopressin, angiotensin II, methylene blue and hydroxocobalamin, are discussed. By integrating evidence from cardiac surgery, critical care and mechanical circulatory support, vasoplegia is presented as a unifying syndrome of extracorporeal circulation. This perspective may support earlier recognition, phenotype-based management and the development of more targeted therapeutic strategies in a clinically significant yet underexplored area of cardiovascular critical care.