Abstract
We are presenting a case of severe dilated cardiomyopathy (DCM) post-mRNA-based coronavirus disease-2019 (COVID-19) vaccine (Pfizer-BioNTech) in a young healthy man. After the second dose of the vaccine, his health rapidly declined, and he developed severe DCM with reduced ejection fraction. Investigations for other causes of DCM were unremarkable. Severe DCM following COVID-19 vaccine injection is a rare but serious condition. It also highlights the importance of close follow-up of pericarditis and perimyocarditis cases post-COVID-19 vaccine and we recommend clinicians have a low threshold for using echocardiography for early diagnosis and management.