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

In multisystem inflammatory syndrome in children (MIS‑C) temporarily associated with coronavirus disease‑19 (COVID‑19), myocardial damage has been reported.

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.

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.

With early recognition and adequate MIS‑C therapy, children recovered entirely, maintained in the short‑term follow‑up period.