Diagnosis of Post Covid-19 Disorders in the Function of the Endothelium

Introduction. One of the characteristics of COVID-19, caused by the SARS-CoV-2 virus, is the broad, nonspecific nature of the pathological processes that develop in almost all organs and organ systems of the human body. At the same time, the development of endothelial dysfunction has been identified by many investigators as the pathological process that integrates these disorders and is considered the primary pathophysiological mechanism in severe cases. Aim. Post-COVID-19 infection survivors in 2021–2022 (n = 502) underwent a Flow-Mediated Dilation (FMD) test of upper arm occlusion by the brachial artery. Materials and methods. In the non-invasive study, endothelial dysfunction (ED) was induced with a pneumatic cuff, thereby inflicting compression only on the distal circulation with reactive hyperemia. Manifestation of ED was evaluated by the diameter of the brachial artery (BA) being less than 10% compared to the baseline, or vasoconstriction. Results. The patients were divided into four groups by the severity of the disease. Group I (n = 262) comprised home-quarantined patients with mild symptoms (HQM); Group II (n = 183), patients hospitalized with moderate symptoms (HMO); Group III (n = 41), patients hospitalized with severe symptoms who required oxygen therapy (HSV); and Group IV (n = 16), patients in the Intensive Care Unit (ICU) hospitalized with critical symptoms (HCR). In HCR (Group IV), the reaction of the BA diameter on the FMD in 100% of cases was vasoconstriction. In HSV (Group III), 37 (90.2%) patients demonstrated a vasospastic reaction of the BA. In HMO (Group II), vasoconstriction was detected in 23 (12.6%) patients, and 29 (15.9%) patients demonstrated a spastic reaction. In HQM (Group I), 27 (10.3%) patients were detected with vasoconstriction, while in 31 patients (11.83%) a BA spastic reaction was recorded. Conclusions. Endothelium-dependent vasodilation determined by FMD is a practical and affordable method for the detection of endothelial dysfunction in post-COVID-19 patients and allows identification of patients with a higher risk of cardiovascular complications.