Создание руководства поддержано Советом по терапевтическим наукам отделения клинической медицины Российской академии наук.

The present work is focused on the study of changes in microcirculation parameters in patients who have undergone COVID-19 by means of wearable laser Doppler flowmetry (LDF) devices. The microcirculatory system is known to play a key role in the pathogenesis of COVID-19, and its disorders manifest themselves long after the patient has recovered. In the present work, microcirculatory changes were studied in dynamics on one patient for 10 days before his disease and 26 days after his recovery, and data from the group of patients undergoing rehabilitation after COVID-19 were compared with the data from a control group. A system consisting of several wearable laser Doppler flowmetry analysers was used for the studies. The patients were found to have reduced cutaneous perfusion and changes in the amplitude–frequency pattern of the LDF signal. The obtained data confirm that microcirculatory bed dysfunction is present in patients for a long period after the recovery from COVID-19.

Дисфункция эндотелия при артериальной гипертензии: причина или следствие?

Acute coronary syndrome (ACS) is caused by an acute mismatch between myocardial oxygen demand and its supply. This mechanism is largely associated with the progression of coronary atherosclerosis in combination with an inflammatory response, hypoxemia, and blood procoagulation. Patients with the coronavirus disease 2019 (COVID-19), aggravated by cardiovascular diseases and comorbidities, are at high risk of ACS.Aim. To analyze the publications, which reflects the development of ACS in patients with COVID-19, its pathogenesis, and clinical course. Material and methods. Literature data were searched using Google Scholar, PubMed, ScienceDirect, and Cyberleninka services. The analysis included data from clinical guidelines on COVID-19, data from clinical studies, reports, and systematic reviews.Results. This literature review summarizes and systematizes the data presented in modern publications, highlights the aspects of the clinical course and pathogenetic mechanisms underlying ACS in patients with COVID-19.Conclusion. The pathogenesis of COVID-19 is inextricably associated with the widespread cytopathic effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), uncontrolled immune response that causes systemic inflammation, as well as the coagulation system activation. In patients with COVID-19, along with the atherosclerosis, these mechanisms significantly increase the risk of ACS and can worsen its in-hospital course.

Background: The manifestations, severity, and mortality of COVID-19 are considered to be associated with the changes in various hematological parameters and in immunity. Associations of immunoglobulin G antibodies against severe acute respiratory syndrome-linked coronavirus (IgG-SARS)-positive status with cardiac function and hematological and biochemical parameters in apparently health subjects are poorly understood. Methods: The present cross-sectional study included 307 healthy volunteers (24–69 years of age; 44.8 ± 8.6 years; 80.4% men) and was initiated in 2019 before the COVID-19 pandemic. COVID-19 episodes were confirmed by detection of IgG-SARS against SARS-CoV-2 S1 RBD to reveal 70 IgG-SARS-positive and 237 negative participants. Numerous ultrasound characteristics were assessed by echocardiography, and 15 hematological and biochemical parameters were assayed in the blood. Descriptive and comparative analysis was based on the IgG-SARS status of the participants. Results: The left ventricular mass index, mitral ratio of peak early to late diastolic filling velocity or flow velocity across the mitral valve, and deceleration time of early mitral inflow were decreased (p < 0.05) in IgG-SARS-positive participants versus those in IgG-SARS-negative participants according to multivariate logistic regression analysis. Erythrocyte sedimentation rate and platelet count were slightly increased, and blood hemoglobin was decreased in IgG-SARS-positive participants compared with those in IgG-SARS-negative participants. Conclusions: LV filling, inflammation, blood coagulation, and hemoglobin appear to be influenced by COVID-19 infection in healthy participants. Our observations contribute to the definition of vulnerabilities in the apparently healthy subjects with long COVID-19. These vulnerabilities may be more severe in patients with certain chronic diseases.

The review describes the skin microcirculation disorders with essential arterial hypertension by the capillaroscopy and laser Doppler flowmetry. The methods are complementary to each other and provide information about the structural and functional state of arteriolar, capillary and venular vessels in the microvasculature. The most common disorders in the skin microvasculature attending the arterial hypertension are vasomotor dysfunction of the microvascular endothelium, a decreasing of the dilator reserve, and capillary rarefaction. The bulk information was obtained in non-acral areas of the skin, where the tissue perfusion is has mainly nutritional pattern. The blood flow pattern in of the skin acral areas, where the sympathetic adrenergic system of regulation dominates, is still unexplored, and tissue perfusion is characterized by a thermoregulatory shunt orientation.