Myocardial damage in multisystem inflammatory syndrome associated with COVID-19 in children and adolescents

BACKGROUND: In multisystem inflammatory syndrome in children (MIS-C) temporarily associated with coronavirus disease-19 (COVID-19), myocardial damage has been reported. MATERIALS AND METHODS: A retrospective observational cohort study included children under 18 who had a myocardial injury related to COVID-19 treated in mother and child health institute from April 2020 to August 2020. Myocardial injury related to COVID-19 was manifested by elevated serum cardiac troponin and NT-proBNP with LV dysfunction, arrhythmias, and coronary arteries (CAs) dilatation or aneurysms. During the short-term follow-up, cardiac testing (electrocardiography, laboratory analysis, echocardiography, 24-h Holter monitoring, exercise stress test, and cardiac magnetic resonance) was performed. RESULTS: Six male adolescents (14.7 ± 2.4 years) were included in the analysis (2/6 had MIS-C shock syndrome). All patients had elevated acute-phase reactants and NT-proBNP, whereas troponins were elevated in 5/6 patients. Echocardiography revealed left ventricular (LV) systolic dysfunction (EF 45.2 ± 6.9%); 2/6 had dilated CAs. IVIG was prescribed to all patients with MIS-C. Four patients required inotropic drug support. During hospitalization, a significant reduction of CRP, LDH, NT-proBNP, and D-dimer (P < 0.05) was registered. LV systolic function recovery was registered 3 days after applied therapy (P < 0.001). None of the patients developed dilated cardiomyopathy or CA aneurysms. CONCLUSIONS: With early recognition and adequate MIS-C therapy, children recovered entirely, maintained in the short-term follow-up period.