Acute Myocardial Infarction and Myocarditis following COVID-19 Vaccination

BACKGROUND: Emerging reports raise concerns on the potential association between the COVID-19 vaccines and cardiac manifestations. We sought to evaluate cardiac complications associated with COVID-19 vaccination in a pooled analysis from our institution's cohort study and systematic review. METHODS: Consecutive patients admitted in a tertiary hospital in Singapore between 1 January 2021 and 31 March 2021, with onset of cardiac manifestations within 14 days following COVID-19 vaccination were studied. Furthermore, a systematic review was performed, with PubMed, Embase, Research Square, MedRxiv, and LitCovid databases accessed from inception up to 29 June 2021. Relevant manuscripts reporting individual patient data on cardiac complications following COVID-19 vaccination were included. RESULTS: Thirty patients were included in the study cohort, with 29 diagnosed with acute myocardial infarction (AMI) and 1 with myocarditis. Five patients developed heart failure, two had cardiogenic shock, three intubated, and one had cardiovascular-related mortality. In the systematic review, 16 studies were included with 41 myocarditis and six AMI cases. In the pooled analysis of the study cohort and the systematic review, 35 patients had AMI and 42 had myocarditis. Majority were men, and myocarditis patients were younger than AMI patients. Myocarditis patients tended to present 72 hours post-vaccination, while AMI patients were older and typically presented 24 hours post-vaccination. Majority with AMI or myocarditis developed symptoms after the first and second vaccination dose respectively. CONCLUSIONS: This pooled analysis of patients presenting with cardiac manifestations following COVID-19 vaccination highlights the differences between myocarditis and AMI presentations in temporal association with the vaccination.