Clinical insights: Resolving the specter of cardiac sequelae in multisystem inflammatory syndrome in children (MIS-C) – A 24-month follow-up case series

Abstract

Background: During the COVID-19 pandemic, multisystem inflammatory syndrome (MIS-C) emerged as a novel and severe complication. Objectives: The present prospective study followed patients in Brazil from February 2020 to December 2022, and evaluated children discharged from reference centers with an MIS-C diagnosis. The aim of the study is to describe long-term cardiac findings. Methods: Following a clinical and imaging procedure, children with MIS-C were followed up. Results: Thirty-six children during hospitalization coursed with fever; 61.1 % presented with gastrointestinal symptoms, 77.7 % with cardiocirculatory manifestations, and 28 % with respiratory issues. Shock was observed in 37 % of patients and the average hospital stay was 9 ± 5 days, with 54 % exhibiting severe symptoms requiring intensive care. Elevated inflammatory and cardiac markers were common; 42 % of patients presented elevated troponin and D-dimer levels. During intensive care, echocardiographic abnormalities were found in 56 % of the patients, including coronary dilation and pericardial effusion. All patients were hospitalized and treated with intravenous immunoglobulin, oral steroids, and acetylsalicylic acid, resulting in 86 % recovery. However, 14 % of the patient had persistent (mild cardiac) alterations at discharge. Sex and previous chronic conditions did not affect the persistence of cardiac findings, whereas marginal age differences indicated that older children tend to have more severe symptoms. BMI was identified as a risk factor but must be considered carefully. Six months post-discharge, all patients successfully recovered from cardiac alterations. Conclusion: Only few case series have reported persistent MIS-C findings, and this case series elicits a positive post-discharge prognosis for MIS-C over time.