Thrombosis is a pathological condition characterized by the formation of a blood clot in the area of the vascular bed.
Indispensable conditions for the occurrence of arterial thrombosis is a violation of the integrity of the vascular wall, changes in the hemostatic system and a slowdown in blood flow. This explains the high frequency of thrombosis in people suffering from obliterating atherosclerosis, diabetes mellitus. Often the development of thrombosis contribute to damage to the walls of the arteries. soft tissue bruises, dislocations and fractures of limb bones, compression of the vascular bundle by a tumor or hematoma. Acute arterial thrombosis may be preceded by angiography – cal research, reconstructive vascular surgery, intra-arterial blood transfusion. Thrombosis also occurs against the background of certain hematologic (polycythemia) and infectious (typhus) diseases.
In all these cases, the response to damage to the endothelium of the vascular wall is adhesion and subsequent platelet aggregation. The resulting aggregates tend to further growth, which is associated with the action of physiologically active substances released from platelets. Released from platelets trombotsitarnge factors and biologically active substances contribute not only platelet aggregation, but also the activation of the blood coagulation system, reducing its fibrinoli – cal activity. Thus, thrombocytic aggregates become a functionally active field in which the activation and interaction of coagulation factors of the blood occurs. As a result, fibrin filaments are adsorbed on the surface of the aggregate and a network structure is formed, which, delaying the formed elements of the blood, turns into a blood clot. With significant inhibition of the lytic link of the hemostatic system, thrombosis can take on a common character.