Ventricular function and tissue characterization by cardiac magnetic resonance imaging following hospitalization for multisystem inflammatory syndrome in children: a prospective study

Abstract

Background Multisystem inflammatory syndrome in children (MIS-C) is a severe life-threatening manifestation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection that often presents with acute cardiac dysfunction and cardiogenic shock. While recovery from acute illness is excellent, the long-term myocardial impact is unknown. Objective To compare cardiac MRI findings in children 6–9 months after their hospitalization with MIS-C against MRI findings in healthy controls to assess for residual myocardial disease. Materials and methods We prospectively performed cardiac MRI on 13 children 6–9 months following their hospitalization with MIS-C: eight of these children had a history of left ventricle ejection fraction (LVEF) < 50%, persistent symptoms, or electrocardiogram (ECG) abnormalities and underwent clinical MRI; five of these children without cardiac abnormalities during their hospitalization underwent research MRIs. We compared their native T1 and T2 mapping values with those of 20 normal controls. Results Cardiac MRI was performed at 13.6 years of age (interquartile range [IQR] 11.9–16.4 years) and 8.2 months (IQR 6.8–9.6 months) following hospitalization. Twelve children displayed normal ejection fraction: left ventricle (LV) 57.2%, IQR 56.1–58.4; right ventricle (RV) 53.1%, IQR 52.0–55.7. One had low–normal LVEF (52%). They had normal extracellular volume (ECV) and normal T2 and native T1 times compared to controls. There was no qualitative evidence of edema. One child had late gadolinium enhancement (LGE) with normal ejection fraction, no edema, and normal T1 and T2 times. When stratifying children who had MIS-C according to history of LVEF <55% on echocardiography, there was no difference in MRI values. Conclusion Although many children with MIS-C present acutely with cardiac dysfunction, residual myocardial damage 6–9 months afterward appears minimal. Long-term implications warrant further study.

SARS-CoV-2 infection and recovery in children: Distinct T cell responses in MIS-C compared to COVID-19

“…We demonstrate that children recovered from MIS-C can maintain SARS-CoV-2–specific antibodies in circulation up to 19 mo after infection at comparable levels to children who recovered from mild infection, however their ability to provide protection against emerging variants may be relatively impaired. Together, these findings indicate that children with MIS-C may develop robust protection from future SARS-CoV-2 infection, an idea consistent with the lack of recurrent MIS-C in previously affected patients ( DiLorenzo et al, 2023 ). In conclusion, our study demonstrates that adaptive immune responses may trigger immunopathology in acute MIS-C, but these same processes may also promote efficacious immune memory.…”

Evaluation of late cardiac effects after multisystem inflammatory syndrome in children

“…Bartoszek et al ( 28 ) could not identify any CMR abnormalities at the 3-month follow-up in 19 children with cardiac involvement during the acute phase of MIS-C, and neither could Barris et al ( 3 ) at the 9-month follow-up. These results contrast with other data that show the presence of LGE, without LV dysfunction or any other clinically significant cardiac abnormalities, in up to 50% after a mean follow-up of 9 months ( 11 , 29 ). We performed a CMR after a mean period of 12 months with a range of 6–28 months and observed normalization of the cardiac function in almost all patients.…”