Myocardial injury patterns on cardiac magnetic resonance: diffuse myocardial damage with prominent septal involvement in adults with severe myocarditis requiring extracorporeal membrane oxygenation

Patients with myocarditis suffering from cardiogenic shock may benefit from extracorporeal membrane oxygenation (ECMO). However, the characteristics of myocardial injury in these patients are unclear. Using cardiac magnetic resonance (CMR), we aimed to investigate cardiac changes in survivors with severe myocarditis treated with ECMO. This retrospective study was conducted at the First Affiliated Hospital with Nanjing Medical University in Nanjing, China, from July 2018 to July 2022. Patients with severe myocarditis who underwent CMR within 30 days after discontinuing ECMO were included in this study. In total, 22 patients (median age: 33 years) were included. Late gadolinium enhancement (LGE) was detected within the interventricular septum (IVS) in all patients. The mean T1, T2, and extracellular volume (ECV) values showed similar distribution patterns to LGE. In an exploratory post-hoc age stratification based on the cohort median age of 33 years, we observed that several quantitative CMR parameters (mean ECV, minimum ECV, maximum ECV, mean T1, maximum T1, and minimum T2) were numerically higher in the older subgroup ( p < 0.05). Myocardial injury was widespread in patients with severe myocarditis receiving ECMO. Survivors of severe myocarditis who required ECMO support presented diffuse myocardial injury as the dominant pattern on early post-weaning CMR examination, with the interventricular septum showing notably prominent lesions among all myocardial segments.