Cardiac Magnetic Resonance Findings of COVID-19 Vaccine Associated Myocarditis at Intermediate Follow Up: a Comparison to Classic Myocarditis and MIS-C Related Myocarditis

ObjectiveTo report intermediate cardiac magnetic resonance (CMR) findings of COVID-19 vaccine associated myocarditis (C-VAM) and compare to classic myocarditis (CM) and multisystem inflammatory syndrome in children (MIS-C).Study DesignRetrospective cohort study including children diagnosed with C-VAM from 5/2021 through 12/2021 with early and intermediate CMR. Patients with CM and MIS-C with intermediate CMR were included for comparison.ResultsThere were 8 patients with C-VAM, 20 with CM, and 61 with MIS-C. Among those with C-VAM, CMR performed at median 3 days (IQR 3, 7) revealed 2/8 patients with left ventricular ejection fraction (LVEF)ConclusionPatients with C-VAM had no evidence of active inflammation or ventricular dysfunction on intermediate CMR although a minority had persistent LGE. Intermediate findings in C-VAM may be favorable compared to CM though LGE is more common compared to MIS-C.