text: Echocardiographic Indicators Associated with Adverse Clinical Course and Cardiac Sequelae in Multisystem Inflammatory Syndrome in Children with Coronavirus Disease 2019 Multisystem inflammatory syndrome in children MIS C associated with coronavirus disease 2019 causes significant cardiovascular involvement which can be a determinant of clinical course and outcome The aim of this study was to investigate whether echocardiographic measures of ventricular function were independently associated with adverse clinical course and cardiac sequelae in patients with MIS C In a longitudinal observational study of 54 patients with MIS C mean age 6 8 4 4 years 46 male 56 African American measures of ventricular function and morphometry at initial presentation predischarge and at a median of 3 and 10 week follow up were retrospectively analyzed and were compared with those in 108 age and gender matched normal control subjects The magnitude of strain is expressed as an absolute value Risk stratification for adverse clinical course and outcomes were analyzed among the tertiles of clinical and echocardiographic data using analysis of variance and univariate and multivariate regression Median left ventricular apical four chamber peak longitudinal strain LVA4LS and left ventricular global longitudinal strain LVGLS at initial presentation were significantly decreased in patients with MIS C compared with the normal cohort 16 2 and 15 1 vs 22 3 and 22 0 respectively P 01 Patients in the lowest LVA4LS tertile 13 had significantly higher C reactive protein and high sensitivity troponin need for intensive care and need for mechanical life support as well as longer hospital length of stay compared with those in the highest tertile 18 5 P 01 Initial LVA4LS and LVGLS were normal in 13 of 54 and 10 of 39 patients respectively There was no mortality In multivariate regression only LVA4LS was associated with both the need for intensive care and length of stay At median 10 week follow up to date seven of 36 patients 19 and six of 25 patients 24 had abnormal LVA4LS and LVGLS respectively Initial LVA4LS 16 2 indicated abnormal LVA4LS at follow up with 100 sensitivity Impaired LVGLS and LVA4LS at initial presentation independently indicate a higher risk for adverse acute clinical course and persistent subclinical left ventricular dysfunction at 10 week follow up suggesting that they could be applied to identify higher risk children with MIS C 