In-depth cardiovascular and pulmonary assessments in children with multisystem inflammatory syndrome after SARS-CoV-2 infection: a case series study

Abstract Objective To perform an in-depth assessment of cardiovascular and pulmonary outcomes in a series of 5 post discharged multisystem inflammatory syndrome (MIS-C) survivors. Methods Data were collected ≅1.9 month after hospital discharge at a tertiary hospital in São Paulo, Brazil. All patients (7-18 years; 3 females) fulfilled the MIS-C diagnosis according to CDC. The battery of tests included: 13 N-ammonia PET-CT imaging, standard echocardiography, brachial flow-mediated dilation using a Doppler ultrasound, cardiopulmonary exercise test, and blood markers. Results Upon PET-CT scans, two patients exhibited severe perfusion defect developed in the left ventricular cavity suggesting extensive myocardial ischemia, and one patient showed persistent mild pericardial effusion. Other two patients had endothelial dysfunction. All patients exhibited abnormal cardiopulmonary reserve during exercise (e.g., low VO2peak). Three patients had abnormal values for D-dimer and fibrinogen. Conclusion This study reveals novel pathological findings in MIS-C patients, which may help optimize treatment protocols in this condition.