Endothelial function disorders in children with COVID-19 infection: results of own study

Purpose - to learn the features of clinical condition and state of endothelial function as the marker of the development of cardiovascular pathology in children who suffered from COVID-19. Materials and methods. The research group consisted of 70 children aged 7-14 without chronic pathology who suffered from COVID-19 and had laboratory confirmation of the disease. Assessment of the functioning of the vessels’ endothelium was done by studying the dynamics of blood flow in the brachial artery and changes of it diameter at rest and during reactive hyperemia after an occlusion test. Statistical assessment of the obtained data was carried out by the application package «Statistica 10.0 for Windows» using the method of variational statistics. Student’s t-test was calculated to assess the reliability of mean values differences. Results. The state of endothelial function show that 85.4% of children after COVID-19 infection had signs of endothelial dysfunction, mainly hypoergic (32.9%) and paradoxical (30%) forms, while normoergic function of the endothelium was found only in 14.6% of children. In the same time in the group of children who did not suffer from COVID-19, was found that the normorergic form registrated in 80.0%, hyperergic endothelial dysfunction was found in 13.3% of children, and hypoergic - in 6.7% of children. Paradoxical endothelial dysfunction was not found in any child from this group. Conclusions. COVID-19 infection has negative consequences on the endothelium function and contributes to the development of endothelial dysfunction regardless of the severity of the disease course. Our results obtained the need of future study to develop an affordable and low-cost algorithm for routine use and identification of children with markers of lesion of cardiovascular system. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.