Stepwise extracorporeal membrane oxygenation conversion strategy with IMPELLA support in giant cell myocarditis complicated by severe hypoxemic respiratory failure due to Mendelson syndrome:A case report

Abstract

Background:Fulminant giant cell myocarditis (GCM) is a rare, rapidly progressive condition that often requires mechanical circulatory support. Management becomes particularly challenging when complicated by severe respiratory failure, necessitating the simultaneous optimization of circulatory and respiratory support. Case presentation:A 66-year-old man presented with sustained ventricular tachycardia and cardiogenic shock, requiring veno-arterial extracorporeal membrane oxygenation (V-A ECMO) with IMPELLA support (ECPELLA). During cardiopulmonary resuscitation, massive aspiration occurred, resulting in severe hypoxemic respiratory failure consistent with Mendelson syndrome. As the cardiac function partially recovered, differential hypoxia developed under V-A ECMO, characterized by inadequate upper-body oxygenation despite preserved systemic perfusion. The ECMO configuration was converted to veno-arterial-venous (V-AV) ECMO, leading to a marked improvement in oxygenation. With further cardiac recovery and persistent respiratory failure, support was transitioned to veno-venous (V-V) ECMO. The patient was successfully weaned from extracorporeal support and mechanical ventilation. Conclusion:This case highlights the importance of recognizing differential hypoxia and implementing stepwise ECMO reconfiguration based on the evolving cardiopulmonary physiology. A flexible, physiology-driven approach may be crucial for optimizing oxygen delivery in patients with combined cardiogenic shock and severe respiratory failure. J. Med. Invest. 73 : 561-565, August, 2026