Absence of cardiac involvement in children with uncomplicated SARS-CoV-2 infection

ABSTRACT

Introduction: The pandemic of SARS-CoV-2 is a major health issue, and involvement of the cardiovascular system is common amongst adult with acute coronavirus disease 2019 (COVID-19). Since the beginning of the epidemic, children seem relatively spared with a low morbidity and mortality. However, multisystem inflammatory syndrome in children (MIS-C) is a rare but severe complication following SARS-CoV-2 infection. Cardiovascular involvement is reported in about 80% of MIS-C cases, with elevated cardiac enzymes, left ventricular dysfunction, shock, coronary artery dilatation, mitral regurgitation and arrhythmias. Although MIS-C seems to be a post-infectious complication, its pathogenesis has not yet been clearly elucidated. It is unknown whether children with uncomplicated SARS-CoV-2 infection can develop subclinical cardiac implication and coronary artery dilatation. Methods: Children with an acute infection of SARS-CoV-2 confirmed by positive RT-PCR test on nasopharyngeal swab between March and May 2020, who didn't meet MIS-C diagnostic criteria, were proposed an outpatient cardiology appointment. Electrocardiogram and echocardiography were performed in all participants. Results: 35 children (17 female) aged 2 months to 16 years (mean 9.2 years) were enrolled after informed consent. Cardiology assessment took place 66 days (range 44 to 100 days) after the test. Shortening fraction of the left ventricle was normal in all subjects (mean shortening fraction 35.25%, range 30-43%). Coronary arteries were normal without dilatation in all 35 children. Moreover, there was no valvar abnormalities and no pericardial effusion. ECGs were normal without conduction abnormalities. Conclusions:Wedidn't observe any subclinical cardiac involvement in our cohort of pediatric patients with uncomplicated SARSCoV-2 infection. Cardiac dysfunction and coronary artery dilatations reported in MIS-C, but never or rarely reported in acute pediatric COVID-19 cases corroborate the hypothesis of a postinfectious syndrome. Further researches are necessary to better understand the underlying mechanisms of cardiovascular involvement after SARS-CoV-2 infection.