Characterization of cardiac function of non-vaccinated, adolescent competitive athletes recovering from COVID-19 disease

Background Myocarditis in children is strongly related to earlier viral infections. SARS Cov-2 virus (COVID-19) infection is often associated with myocarditis in adults. Athletes are more prone to develop severe myocarditis in relation to viral infections due to the increased cardiac load required by sport activities. It is also known that certain SARS Cov-2 virus vaccines increase the incidence of myocarditis among young athletes. Aim Thus, the aim of the present study was to retrospectively assess the cardiovascular status of non-vaccinated, young, competitive athletes recovering from COVID-19 disease. Methods and Study sample Data from 108, competitive young athletes (13–17 years old, 50 girls, 58 boys) participating in examinations prior returning to regular sports activity were collected. All participant has documented COVID-19 infection with varying disease severity. The cardiovascular diagnostic evaluation consisted of oscillometric blood pressure measurements, 12-lead electrocardiograms, transthoracic echocardiography, and measuring plasma high-sensitive troponin-I levels. Results Systolic and pulse pressures were ∼10 mmHg higher in boys compared to girls (systolic pressures: 120.8 ± 10.8 vs. 111.6 ± 10 mmHg, pulse pressures: 49.8 ± 11.8 vs. 41.8 ± 10.7 mmHg), whereas diastolic and mean blood pressures were not different between sexes. 3 asymptomatic subjects (1 girl and 2 boys) had slightly elevated plasma levels of troponin-I (187, 122, 62 ng L −1 ). The diagnostic modalities used did not detect any cardiac pathological changes. Cardiac MRI examinations in the 3 cases did not show signs of myocarditis. In all three cases troponin-I elevations spontaneously returned to normal range at the follow-up. Mild post-Covid symptoms were present in 24% of the sample. Conclusions The data of the present study suggest that 1) confirmed myocarditis after recovering from COVID-19 disease in non-vaccinated young competitive athletes was not present, 2) the elevated troponin-I levels in three athletes were unlikely due to COVID-19 infection. Thus, based on the findings of the present study and data from other studies, we conclude that prevalence of myocarditis related to COVID-19 virus infection does not differ substantially from that of other (non-Covid) viral infections thus the return to sport activity testing protocols should be similarly applied.