Successful ECMO support for cardiogenic shock induced by immune checkpoint inhibitor-associated myocarditis: a case report and literature review.

Objectives: Immune checkpoint inhibitor (ICI)-associated myocarditis is a rare but potentially fatal immune-related adverse event that can rapidly progress to life-threatening arrhythmias and cardiogenic shock, often necessitating mechanical circulatory support. Extracorporeal membrane oxygenation (ECMO) has emerged as a critical life-saving intervention in such cases. However, the role of ECMO in treating ICI-associated myocarditis remains underexplored, with limited literature available. Methods: We present a case of fulminant ICI-associated myocarditis with cardiogenic shock successfully managed with ECMO. Additionally, we review and summarize data from 13 ECMO-assisted patients with ICI-associated myocarditis to provide insights into the clinical characteristics, management strategies, and outcomes. Main results: Among the 13 patients (with a mean age 59.08 years), monotherapy using nivolumab or pembrolizumab represented the predominant ICI treatment regimen. The median treatment cycle was 3.0 (IQR: 2.0 ~ 7.0), and the median duration from first administration to myocarditis onset was 77.0 (IQR: 20.5 ~ 250.0) days. The median duration of myocarditis symptoms was 19.0 (IQR: 15.5 ~ 42.5) days. Common presenting symptoms included fever and dyspnea, while most patients exhibited elevated myocardial enzymes and BNP levels, arrhythmias, and an average left ventricular ejection fraction (LVEF) of 38.31% at admission. Myocardial biopsy was the primary diagnostic method. In addition to immunosuppressive therapy, most patients also required intra-aortic balloon pump (IABP) support. The median duration of ECMO and IABP support was 9.0 (IQR: 6.5 ~ 15.5) days and 11.5 (IQR: 7.5 ~ 13.0) days, respectively. Ultimately, nine of the thirteen patients (69.23%) survived. Conclusions: Our analysis demonstrates ECMO's potential as a bridge-to-recovery strategy for severe ICI-associated myocarditis with cardiogenic shock. The observed survival rate of 69.23% supports its judicious use in conjunction with prompt immunosuppression. Prospective studies are warranted to optimize ECMO initiation criteria, duration, and combination strategies with other circulatory support modalities.