The Role of Cardiac Magnetic Resonance in mRNA COVID-19 Vaccine-Related Myopericarditis: An Evolutive Case Series.

Numerous cases of myocarditis related to mRNA vaccines for COVID-19 have recently been described, usually in young men. Long-term evolutive cardiac magnetic resonance imaging (CMR) data are lacking. We describe four consecutive cases of COVID-19 vaccine-induced myocarditis. The pathological findings of cardiac magnetic resonance confirmed the diagnosis in the acute phase, showing edema, as well as pericardial enhancement, with light pericardial effusion and late gadolinium enhancement (LGE), predominantly in the inferolateral wall. These cases highlight the unique value of cardiac magnetic resonance in patients with suspected myocarditis induced by COVID-19 RNAm vaccines as a tool to confirm the diagnosis, avoiding other invasive techniques, as well as for the long-term follow-up of patients. Our iterative CMR imaging demonstrated frequent long-term LGE persistence.