Emergency department presentations for chest complaints after mRNA COVID‐19 vaccinations in children and adolescents.

Objective: To investigate characteristics and management of children presenting with chest complaints to a tertiary paediatric ED post‐mRNA COVID‐19 vaccine. Methods: This was a retrospective medical record review with data linkage to the Australian Immunisation Register. The study setting was the Royal Children's Hospital, Melbourne, Australia. Children <18 years who had a troponin blood test performed in hospital within 14 days of receiving mRNA COVID‐19 vaccination were included. Elevated troponin and myocarditis or pericarditis as per Brighton criteria was the primary outcome. Vaccination status, length of stay, investigations and clinical management were secondary outcomes. Results: Six hundred and ten patients had a troponin test in 13 months. After exclusion of trauma‐related tests (n = 31), known cardiac patients (n = 75) and others (n = 145), 359 troponins were obtained due to chest complaints and related symptoms, with 283 troponins assessed to be mRNA vaccination‐related. There was a temporal peak in presentations with a 30‐fold monthly increase in troponin post‐commencement of mRNA COVID‐19 vaccines. In those with chest complaints following mRNA vaccination, mean age was 14 years and 50.4% were female. Fourteen out of 283 (5%) vaccine‐related troponins were abnormal with 14 patients assessed to have vaccine‐associated myocarditis. No patients had pericarditis. Conclusions: There was a large number of possible mRNA COVID‐19 vaccine‐related chest complaints presenting to the ED. Few patients had abnormal troponins or myocarditis. [ABSTRACT FROM AUTHOR]