What is Known: • Myocarditis is a rare side effect of COVID-19 mRNA vaccine. •Late gadolinium enhancement is present on most cardiac magnetic resonance at the time of acute presentation.

What is New: •Late gadolinium enhancement improved on all repeat cardiac magnetic resonance at 3-month follow-up. •Most patients still had a small amount of late gadolinium enhancement, the clinical significance of which is yet to be determined.