Medium-Term Cardiac Outcomes in Young People with Multi-system Inflammatory Syndrome: The Era of COVID-19

Abstract

Multi-system inflammatory syndrome in children (MIS-C) causes widespread inflammation including a pancarditis in the weeks following a COVID infection. As we prepare for further coronavirus surges, understanding the medium-term cardiac impacts of this condition is important for allocating healthcare resources. A retrospective single-center study of 67 consecutive patients with MIS-C was performed evaluating echocardiographic and electrocardiographic (ECG) findings to determine the point of worst cardiac dysfunction during the admission, then at intervals of 6-8 weeks and 6-8 months. Worst cardiac function occurred 6.8 ± 2.4 days after the onset of fever with mean 3D left ventricle (LV) ejection fraction (EF) 50.5 ± 9.8%. A pancarditis was typically present: 46.3% had cardiac impairment; 31.3% had pericardial effusion; 26.8% demonstrated moderate (or worse) valvar regurgitation; and 26.8% had coronary dilatation. Cardiac function normalized in all patients by 6-8 weeks (mean 3D LV EF 61.3 ± 4.4%, p < 0.001 compared to presentation). Coronary dilatation resolved in all but one patient who initially developed large aneurysms at presentation, which persisted 6 months later. ECG changes predominantly featured T-wave changes resolving at follow-up. Adverse events included need for ECMO (n = 2), death as an ECMO-related complication (n = 1), LV thrombus formation (n = 1), and subendocardial infarction (n = 1). MIS-C causes a pancarditis. In the majority, discharge from long-term follow-up can be considered as full cardiac recovery is expected by 8 weeks. The exception includes patients with medium sized aneurysms or greater as these may persist and require on-going surveillance.

Keywords: Aneurysm; Carditis; Children; Covid; Multisystem inflammation; SARS-Cov2.

Fig. 1

a Three dimensional Ejection Fraction (3D LVEF) improved at 6–8 weeks follow-up and remained in normal limits 6 months after. b Left ventricular Global Longitudinal Strain (GLS) was the first parameter to be affected in the course of MIS-C. It normalized at 6–8 weeks and remained within normal limits at 6 m follow-up. c The Left Ventricular Fractional Shortening was the least affected parameter in the LV function assessment and was not proven sensitive enough to assess cardiac function and the changes of it. However, there was improvement in the parameter values at 6–8 weeks follow-up and no significant further improvement at 6 months

Fig. 2

Changes in coronary artery Z score measurements over time. Top left panel shows the right coronary artery (RCA). Top right panel shows the left main coronary artery (LMCA). Bottom left shows the left anterior descending artery (LAD). Bottom right shows the left circumflex artery (LCx). Timepoint one coincides with largest measurement during admission; timepoint two coincides with the first follow-up appointment at 6–8 weeks; and timepoint three coincides with the follow-up appointment at 6–8 months

Fig. 3

Two chamber view of the left ventricle with at least two thromboses seen in the cavity