Cardiac inflammation associated with COVID-19 mRNA vaccination in patients with and without previous myocarditis

BACKGROUND: mRNA COVID-19 vaccines have been associated with myocarditis in the general population. How-ever, application of gold standard techniques is often missing, and data about patients with history of myocarditis have not been reported yet.METHODS: We evaluated 21 patients (median age 27, 86% males) for suspected myocarditis after receiving mRNA COVID-19 vaccine. We divided cases with previous diagnosis of myocarditis (PM, N.=7), from naive controls (NM, N.=14). All patients were investigated thoroughly by cardiac magnetic resonance (100%) with or without endomyocar-dial biopsy (14%).RESULTS: Overall, 57% of patients met updated Lake Louise criteria and none fulfilled Dallas criteria, with no remark-able differences between groups. Acute coronary syndrome-like presentation was more frequent in NM with earlier normalization of troponin than PM. NM and PM already healed from myocarditis were clinically comparable, whereas PM with active inflammation had subtle presentation and were evaluated for immunosuppressive therapy modulation. None had fulminant myocarditis and/or malignant ventricular arrhythmia at presentation. No major cardiac events oc-curred by 3 months.CONCLUSIONS: In this study, the suspicion of mRNA COVID-19 vaccine-associated myocarditis was inconstantly confirmed by gold standard diagnostics. Myocarditis was uncomplicated in both PM and NM patients. Larger studies with longer follow-up are needed to validate COVID-19 vaccination in this population.(Cite this article as: Kaufmann CC, Villatore A, Heugl M, Kvakan H, Zweiker D, Sala S, et al. Cardiac inflammation as-sociated with COVID-19 mRNA vaccination in patients with and without previous myocarditis. Minerva Cardiol Angiol 2023;71:242-8. DOI: 10.23736/S2724-5683.22.06204-4)