Features of venous blood circulation and valve function in the lower extremities according to duplex scanning data and morphofunctional studies

Aim. To study the mechanisms of venous return and the functioning features of lower extremity venous valves in horizontal and vertical positions.

Methods. The study, conducted from April 2019 to December 2020, included 100 people. The study participants were divided into 2 groups. The first group was represented by 44 patients (88 limbs) with varicose veins, whose venous system was examined by duplex ultrasound scanning during inpatient rehabilitation. The second (control) group consisted of 56 healthy individuals (92 limbs) without visible signs of venous pathology who underwent an outpatient examination of the venous system. The average age of the patients in the two groups was 49.2±2.4 and 51.1±1 years, respectively; women predominated in both groups. The qualitative and quantitative parameters of venous blood flow were studied in the study. Venous valvular insufficiency was assessed by using reflux duration and the Psatakis index. A morphometric study was conducted on 140 limbs of 48 human corpses, from which venous fragments were taken for biomechanical studies of the valves. The clinical characteristics of patients are presented by descriptive statistics, quantitative parameters are reported as the mean value (M) and standard deviation (SD). The differences were tested for significance by using the Student's t-test.

Results. In the study, we introduced the concept of the valve index, the aspect ratio of the ellipse, the shape of which has a venous valve in cross-section. Duplex ultrasound scanning, as well as a morphofunctional examination of the valves, made it possible to establish that the valve index is significantly higher in the presence of signs of varicose veins, which indicates dilation and incipient varicose vein, which leads to valvular insufficiency. The elasticity index defined by us, as the indicator of change in the venous lumen size, measured by the ratio of its diameters, also significantly (p=0.034) differed in the studied groups: the elasticity index in the group of healthy people was 1.37±0.11, in the group of patients with varicose veins — 1.56±0.17. The studied factors allowed us to develop a test that has an important prognostic value for the early diagnosis of varicose veins as well as the implementation of preventive health measures.

Conclusion. The features of venous blood circulation and valve function studied in the study not only have prognostic value for the early diagnosis of varicose veins but are also of practical interest for developing methods of surgical correction of venous valvular insufficiency.