ABSTRACT
Multisystem inflammatory syndrome in children (MIS-C) after COVID-19 is commonly associated with cardiac involvement. Studies found myocardial dysfunction, as measured by decreased ejection fraction and abnormal strain, to be common early in illness. However, there is limited data on longitudinal cardiac outcomes. We aim to describe the evolution of cardiac findings in pediatric MIS-C from acute illness through at least 2-month follow-up. A retrospective single-center review of 36 patients admitted with MIS-C from April 2020 through September 2021 was performed. Echocardiographic data including cardiac function and global longitudinal strain (GLS) were analyzed at initial presentation, discharge, 2-4-week follow-up, and at least 2-month follow-up. Patients with mild and severe disease, normal and abnormal left ventricular ejection fraction (LVEF), and normal and abnormal GLS at presentation were compared. On presentation, 42% of patients with MIS-C had decreased LVEF < 55%. In patients in whom GLS was obtained (N = 18), 44% were abnormal (GLS < |- 18|%). Of patients with normal LVEF, 22% had abnormal GLS. There were no significant differences in troponin or brain natriuretic peptide between those with normal and abnormal LVEF. In most MIS-C patients with initial LVEF < 55% (90%), LVEF normalized upon discharge. At 2-month follow-up, all patients had normal LVEF with 21% having persistently abnormal GLS. Myocardial systolic dysfunction and abnormal deformation were common findings in MIS-C at presentation. While EF often normalized by 2 months, persistently abnormal GLS was more common, suggesting ongoing subclinical dysfunction. Our study offers an optimistic outlook for recovery in patients with MIS-C and carditis, however ongoing investigation for longitudinal effects is warranted.
ABSTRACT
BACKGROUND: A novel paediatric disease, multi-system inflammatory syndrome in children, has emerged during the 2019 coronavirus disease pandemic. OBJECTIVES: To describe the short-term evolution of cardiac complications and associated risk factors in patients with multi-system inflammatory syndrome in children. METHODS: Retrospective single-centre study of confirmed multi-system inflammatory syndrome in children treated from 29 March, 2020 to 1 September, 2020. Cardiac complications during the acute phase were defined as decreased systolic function, coronary artery abnormalities, pericardial effusion, or mitral and/or tricuspid valve regurgitation. Patients with or without cardiac complications were compared with chi-square, Fisher's exact, and Wilcoxon rank sum. RESULTS: Thirty-nine children with median (interquartile range) age 7.8 (3.6-12.7) years were included. Nineteen (49%) patients developed cardiac complications including systolic dysfunction (33%), valvular regurgitation (31%), coronary artery abnormalities (18%), and pericardial effusion (5%). At the time of the most recent follow-up, at a median (interquartile range) of 49 (26-61) days, cardiac complications resolved in 16/19 (84%) patients. Two patients had persistent mild systolic dysfunction and one patient had persistent coronary artery abnormality. Children with cardiac complications were more likely to have higher N-terminal B-type natriuretic peptide (p = 0.01), higher white blood cell count (p = 0.01), higher neutrophil count (p = 0.02), severe lymphopenia (p = 0.05), use of milrinone (p = 0.03), and intensive care requirement (p = 0.04). CONCLUSION: Patients with multi-system inflammatory syndrome in children had a high rate of cardiac complications in the acute phase, with associated inflammatory markers. Although cardiac complications resolved in 84% of patients, further long-term studies are needed to assess if the cardiac abnormalities (transient or persistent) are associated with major cardiac events.