Multisystem inflammatory syndrome in children: Salient echocardiogram findings in the acute phase and longitudinal follow-up

Background Coronary artery (CA) abnormalities and left ventricular (LV) systolic dysfunction have been reported in multisystem inflammatory syndrome in children (MIS-C);however, a thorough review of all findings on transthoracic echocardiogram (TTE) with long term follow-up is lacking. Objectives Comprehensively describe the findings on TTE during the acute phase of MIS-C and how those findings change on serial follow-up 6 months after diagnosis. Methods Pediatric patients meeting CDC criteria for MIS-C were included, with data collected from acute phase (T0), outpatient follow-up at 2 weeks (T1), 6–8 weeks (T2), and 6 months (T3), including TTE findings of descending aorta Doppler profile, CA abnormalities, valvar regurgitation, LV systolic function and pericardial effusion. Results Fifty patients (52% male) were included;45 (90%) were SARS-CoV-2 IgG antibody positive, 13 (26%) PCR positive, and 8 (16%) positive for both. Mean age was 8.3 years (range 9 months - 17 years). Holodiastolic flow reversal in descending aorta was seen in 72% at T0, in 6% at T1, with complete resolution in all by T2. CA abnormalities were seen in 52% at T0, 31% at T1, 13% at T2 and none at T3. Mitral regurgitation was present in 84% at T0, 40% at T1, 36% at T2, and 24% by T3. LV systolic dysfunction (ejection fraction <55%) occurred in 52% at T0, with resolution by discharge in 69%, and complete resolution by T2. Trivial to small pericardial effusion was present in 48% at T0, 13% at T1, 3% at T2 and 4% by T3. Conclusion In addition to CA abnormalities and LV systolic dysfunction, holodiastolic flow reversal in the descending aorta, valvar regurgitation and pericardial effusion are prominent findings in MIS-C. Longitudinal follow-up shows improvement in all.

Six Month Follow-up of Patients With Multi-System Inflammatory Syndrome in Children.

BACKGROUND AND OBJECTIVES: Myocardial dysfunction and coronary abnormalities are prominent features of multisystem inflammatory syndrome in children (MIS-C). In this study we aim to evaluate the early and midterm outcomes of MIS-C. METHODS: This is a longitudinal 6-month cohort study of all children admitted and treated for MIS-C from April 17 to June 20, 2020. Patients were followed ∼2 weeks, 8 weeks, and 6 months postadmission, with those with coronary aneurysms evaluated more frequently. RESULTS: Acutely, 31 (62%) patients required intensive care with vasoactive support, 26 (52%) had left ventricular (LV) systolic dysfunction, 16 (32%) had LV diastolic dysfunction, 8 (16%) had coronary aneurysms (z score ≥2.5), and 4 (8%) had coronary dilation (z score <2.5). A total of 48 patients (96%) received immunomodulatory treatment. At 2 weeks, there was persistent mild LV systolic dysfunction in 1 patient, coronary aneurysms in 2, and dilated coronary artery in 1. By 8 weeks through 6 months, all patients returned to functional baseline with normal LV systolic function and resolution of coronary abnormalities. Cardiac MRI performed during recovery in select patients revealed no myocardial edema or fibrosis. Some patients demonstrated persistent diastolic dysfunction at 2 weeks (5, 11%), 8 weeks (4, 9%), and 6 months (1, 4%). CONCLUSIONS: Children with MIS-C treated with immunomodulators have favorable early outcomes with no mortality, normalization of LV systolic function, recovery of coronary abnormalities, and no inflammation or scarring on cardiac MRI. Persistence of diastolic dysfunction is of uncertain significance and indicates need for larger studies to improve understanding of MIS-C. These findings may help guide clinical management, outpatient monitoring, and considerations for sports clearance.

Characteristics, Cardiac Involvement, and Outcomes of Multisystem Inflammatory Syndrome of Childhood Associated with severe acute respiratory syndrome coronavirus 2 Infection.

We report on the presentation and course of 33 children with multisystem inflammatory syndrome in children and confirmed severe acute respiratory syndrome coronavirus 2 infection. Hemodynamic instability and cardiac dysfunction were prominent findings, with most patients exhibiting rapid resolution following anti-inflammatory therapy.