COLLATERAL BLOOD FLOW IN THROMBOSIS IN THE ANKLE-POPLITEAL AND POPLITEAL-FEMORAL SEGMENTS OF THE VENOUS SYSTEM OF THE LOWER LIMBS WITH INVOLVEMENT POPLITEAL VENOUS COLLECTOR

Thrombosis of the veins of the lower extremities plays a significant role in vascular pathology. Lifestyle, concomitant pathologies and provoking factors disrupt the stability of the Virchow's Triad and lead to thrombosis, severe complications and adverse long-term consequences. The aim of research: to evaluate the compensatory possibilities of the collateral blood flow in the popliteal venous collector in the acute venous thrombosis. Rationale for the research. Normally, 90% of blood flows through the main veins. At their thrombosis there is a redistribution of outflow and the most part of blood is taken away by collateral vessels. Knowledge of the functional capabilities of collateral blood flow is an additional criterion for predicting possible complications and severity of the disease. Methods. The analysis is made of results examination and operative treatment of 790 patients with the 107 «Art of Medicine» ISSN 2521-1455 (Print) ISSN 2523-4250 (Online) 4 (16) жовтень-грудень, 2020 acute thrombosis in the vena cava inferior system and being treated at the Transcarpathian Regional Clinical Hospital A. Novak and the Transcarpathian Regional Clinical Oncology Center during 2006 – 2016. Laboratory examination methods were used to examine patients, including instrumental ones: ultrasound duplex scanning, X-ray phlebography, СТ, radionuclide phleboscintigraphy and ultrasound scanning of heart. During the radionuclide phleboscintigraphy of patients at rest and during physical activity, the function of the muscle-venous pump of the tibial was evaluated: the average transport time, the linear speed of blood flow and the loading index. In patients with thrombosis of the tibia-popliteal venous segment, a significant slowing of the passage of radiopharmaceutical on the deep venous system was observed, which is reflected in the increase of the average time of transport through the veins of the tibia and femoral to 59.4 ± 4.02 s, reducing the linear speed of blood flow to 2.1 0.61 cm / s and load index up to 1.6 ± 0.49 units, in this case, deep veins are contrasted unevenly, the phleboscintigrams showing the image of collateral, mainly muscular, and subcutaneous veins, through which the main blood flow from the extremity can take place. In this case, the correlation of volume blood flow of the main and collateral veins averaged 40% and 60%, respectively. Conclusions. The absence of valves in the muscular venous sinuses of the tibial, their larger diameter relative to the other veins of the tibial, and prolonged hypodynamia, adversely affect the work of the muscle-venous pump, which is one of the preconditions for thrombus formation in this area. In this case, the formation of thrombotic masses in the deep veins of the lower extremity in 89.2% of patients begins in the small muscular branches of the tibia, and their spread to the popliteal vein creates optimal conditions for fragmentation and thromboembolism.