Three-Dimensional Echocardiography and Global Longitudinal Strain in Follow-Up After Multisystem Inflammatory Syndrome in Children: Six-Month, Single-Center, Prospective Study

Abstract

To assess the potential long-term cardiac effects after multisystem inflammatory syndrome in children (MIS-C) with cardiovascular involvement in the acute phase. 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, 3D-echocardiography and global longitudinal strain were used to assess ventricular function. The study enrolled 172 children aged 1-17 years (median 8 years). The means of ejection fraction (EF) and global longitudinal strain (GLS) for both ventricles were within normal limits after 6 weeks with no relationship with initial severity: left ventricular ejection fraction (EF) 60 (59-63)%, left ventricular (LV) GLS -21.08 (-18.63 - -23.2)%, right ventricular (RV) EF 64 (62-67)%, and RV GLS -22.8 (-20.5 - -24.5)%. Further, statistically significant improvement of LV function was observed after 6 months - LVEF 63 (62-65)%, LV GLS -22.55 (-21.05 - -24.25)%; p<0.05, but 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. 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.