Natural History of Myocardial Injury After COVID-19 Vaccine-Associated Myocarditis.

Background: Acute myocarditis is a rare complication of mRNA-based COVID-19 vaccination. Little is known about the natural history of this complication.

Methods: Baseline and convalescent (≥ 90 days) cardiac magnetic resonance (CMR) imaging assessments were performed in 20 consecutive patients meeting Updated Lake Louise Criteria for acute myocarditis within 10 days of mRNA-based vaccination.