RESUMEN
OBJECTIVE: To assess the potential long-term cardiac effects after multisystem inflammatory syndrome in children (MIS-C) with cardiovascular involvement in the acute phase. STUDY DESIGN: Our prospective study involved children consecutively diagnosed with MIS-C between October 2020 and February 2022 and followed 6 weeks and 6 months after the disease. In patients with severe cardiac involvement during the acute phase, an additional check-up after 3 months was scheduled. In all patients at all check-ups, 3-dimensional echocardiography and global longitudinal strain (GLS) were used to assess ventricular function. RESULTS: The study enrolled 172 children aged 1-17 years (median, 8 years). The means of ejection fraction (EF) and GLS for both ventricles were within normal limits after 6 weeks with no relationship with initial severity: left ventricular EF (LVEF) 60% (59%-63%), LV GLS -21.08% (-18.63% to -23.2%), right ventricular (RV) EF 64% (62%-67%), and RV GLS -22.8% (-20.5% to -24.5%). Further, statistically significant improvement of LV function was observed after 6 months-LVEF 63% (62%-65%) and LV GLS -22.55% (-21.05% to -24.25%; P < .05); however, RV function remained unchanged. The group with severe cardiac involvement showed LV function recovery pattern with no significant improvement between 6 weeks and 3 months after MIS-C, while still improving between 3 and 6 months after discharge. CONCLUSIONS: LV and RV function is within normal limits 6 weeks after MIS-C regardless of severity of cardiovascular involvement; LV function improves further between 6 weeks and 6 months after the disease. The long-term prognosis is optimistic with full recovery of cardiac function.
RESUMEN
Presently, the whole globe is struggling the tough challenge of the COVID-19 pandemic. Vaccination remains the most effective and safe COVID-19 weapon for adults and in the paediatric population. Aside from possible mild and moderate post-vaccination side effects, more severe side effects may occur. We retrospectively analysed a group of 5 teenagers aged from 15 to 17 years with obesity/overweight (BMI ranging from 24.8 to 30) who presented typical myocarditis symptoms following the first or second dose (3 and 2 patients, respectively) of the COVID-19 vaccine. In the whole study group, a significant increase in troponin serum concentration was observed (1674-37,279.6 ng/L) with a further quick reduction within 3-4 days. In all patients, ST segments elevation or depression with repolarisation time abnormalities in electrocardiography were noticed. Chest X-ray results were within normal limits. Echocardiography showed normal left ventricular diameter (47-56.2 mm) with ejection fraction between 61-72%. All patients were diagnosed with myocarditis based on cardiac magnetic resonance (CMR) imaging. During further hospitalisation, swift clinical improvement was notable. Follow-up in the whole study group was obtained after 106-134 days from initial CMR, revealing no myocarditis symptoms, proper troponin level, and no ECG or echocardiographic abnormalities. At the same time, persistent myocardium injury features were detected in the whole study group, including ongoing myocarditis. COVID-19-vaccine-induced myocarditis seems to be a mild disease with fast clinical recovery, but the complete resolution of the inflammatory process may last over 3 months. Further follow-up and investigation for assessing subsequent implications and long-term COVID-19-vaccine-induced myocarditis is required.