Strain in children with MIS-C and acute COVID-19.

Context: Cardiac injury has been described in both acute COVID-19 and the multisystem inflammatory syndrome in children (MIS-C). Echocardiographic strain has been shown to be a sensitive measure of systolic function. Aims: We sought to describe strain findings in both the groups on initial presentation and follow-up. Settings and Design: A retrospective study analyzing echocardiograms of all patients presenting with acute COVID-19 infection and MIS-C at our institution between March 2020 and December 2020 was performed. Subjects and Methods: TOMTEC software was used for strain analysis in both the study groups (COVID-19 and MIS-C) and age-matched healthy controls. Strain was correlated with LV ejection fraction (EF) and serum troponin levels. Results: Forty-five patients (34 - MIS-C and 11 - COVID-19) met the inclusion criteria. There was a statistically significant decrease in LV longitudinal strain (P < 0.001), LV circumferential strain (P < 0.001), and left atrial strain (P = 0.014) in the MIS-C group when compared to the control group. There was a statistically significant decrease in LV longitudinal strain (P = 0.028) in the acute COVID-19 group. All patients with abnormal left ventricular EF (LVEF) had abnormal strain. However, 14 (41%) patients in the MIS-C group and 3 (27%) in the acute COVID-19 group had preserved LVEF but abnormal strain. There was a significant correlation with LV longitudinal strain (P = 0.005) and LVEF (P = 0.002) and troponin in patients with MIS-C. Abnormal strain persisted in one-third of patients in the MIS-C and acute COVID-19 groups on outpatient follow-up. Conclusions: Patients with MIS-C and acute COVID-19 can develop myocardial dysfunction as seen by abnormal strain. LV longitudinal strain correlates with cardiac injury as measured by serum troponin in patients with MIS-C. Strain may provide an additional tool in detecting subtle myocardial dysfunction. It can be routinely employed at diagnosis and at follow-up evaluation of these patients.

Cardiac Findings in Pediatric Patients With Multisystem Inflammatory Syndrome in Children Associated With COVID-19.

BACKGROUND: The overall severity of cardiac disease secondary to acute SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) infection in children appears to be much lower when compared with adults. However, the newly described multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19) has been associated with cardiac complications. METHODS: We reviewed the clinical course and cardiac testing results in pediatric patients hospitalized with MIS-C at 2 large hospital systems in the New York City metropolitan area over a 3-month period. RESULTS: Of the 33 patients (median age 2.8 years) in the study cohort, 24 (73%) had at least one abnormality in cardiac testing: abnormal electrocardiogram (48%), elevated brain natriuretic peptide (43%), abnormal echocardiogram (30%), and/or elevated troponin (21%). Electrocardiogram and echocardiogram abnormalities all resolved by the 2-week outpatient follow-up cardiology visit. CONCLUSION: While 73% of pediatric patients with MIS-C had evidence of abnormal cardiac testing on hospital admission in our study, all cardiac testing was normal by outpatient hospital discharge follow-up. Cardiac screening tests should be performed in all patients diagnosed with MIS-C given the high rate of abnormal cardiac findings in our study cohort.