Myocarditis; This is a literature report.  A 25-year-old male with well-controlled Crohn's disease (not prescribed any medications) presented to the emergency department with chest pain. The chest pain began the day prior to presentation, worse with inspiration and with associated jaw pain. He reported that he received his second dose of the COVID-19 vaccine (BNT162b2 Pfizer/BioNTech) four days prior to presentation. He experienced malaise and myalgias that resolved within twenty-four hours after receiving the vaccine. Labs were significant for a Troponin T that peaked at 0.74 ng/ml (reference < 0:2 ng/ml). Tick panel (for Lyme, anaplasmosis, babesiosis, and ehrlichiosis) was negative since these are part of the differential work-up of myocarditis. His electrocardiogram did not show any ischemic changes, and echocardiogram was significant for low normal left ventricular ejection fraction (LVEF) of 50%. He was admitted for further work-up and started on colchicine and ibuprofen for presumed myopericarditis. He underwent cardiac MRI which showed a left ventricular fraction of 56% and findings consistent with myocarditis with myocardial edema seen by T2 mapping and myocardial injury with focal late gadolinium enhancement (LGE) with multiple foci in the midwall. He did not have evidence of pericardial inflammation. He did not undergo endomyocardial biopsy. COVID-19 polymerase chain reaction (PCR) was negative. During his hospital stay, he was monitored on telemetry without any arrhythmias observed. He was discharged on low-dose beta-blocker with plans for repeat outpatient echocardiogram and cardiac monitor to screen for any arrhythmias as well as activity restriction. Authors describe three cases of myocarditis in young, healthy patients following COVID-19 vaccine administration. The temporal timing of the cases correlates with similar reports in literature of myocarditis occurring 12-96 hours following immunization with an mRNA COVID-19 vaccine. These cases demonstrate a similar temporal relationship, increasing the likelihood of causality. This safety signal was not clinically apparent in the early vaccine experience, raising the possibility that the association is purely coincidental as viruses responsible for myocarditis follow a seasonal distribution. All three patients were ruled out for COVID-19 infection using the Centers for Disease Control and Prevention- (CDC-) approved gold standard test: polymerase chain reaction (PCR). Previous reports had demonstrated an association between COVID-19 infection and myocarditis. Routine antigen or antibody testing is not part of the clinical work flow, and some have questioned the utility of antibody testing in the post vaccination cohort. Conclusion: There have been early reports of a presumed link between COVID-19 vaccination and subsequent development of myocarditis, but no causative link has been established. The cases add to others where a temporal relationship between vaccination and myocarditis has been described. Ultimately, further exploration of this clinical phenomenon is warranted. Clinical course: EKG: lateral ST elevation myocardial infarction.   No follow-up attempts are possible; information about lot/batch number cannot be obtained. No further information is expected.; Sender's Comments: As there is limited information in the case provided, the causal association between the event myocarditis and the suspect drug BNT162N2 cannot be excluded.  The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.,Linked Report(s) : US-PFIZER INC-202101620016 Same article/ drug/event and different patient