THROMBOSIS

THROMBOZ - lifelong coagulation of blood in the lumen of the vessels or cavities of the heart. A thrombus is a condensed mass of coagulated blood. The leading factors in the pathogenesis of thrombosis are damage to the walls of blood vessels, slowing or disturbing blood flow, as well as changes in its physico-chemical properties, leading to increased coagulability. Damage to the vessel wall is possible with atherosclerosis, inflammation of the walls of the arteries (endarteritis), veins (thrombophlebitis), as well as with damage to the endothelium due to infection, intoxication, trauma. The most common thrombi form in the veins, where the blood flow is slowed. With an increase in blood viscosity, generalized thrombosis may develop.

Thrombi usually attach to the wall of the vessel, they look like semi-dry crumbling dense masses; The surface of blood clots, as a rule, corrugated. Large thrombi have a head (the site of the initial formation of the thrombus), the body and tail. A thrombus is pristenochnym; In this case part of the lumen of the vessel remains free. The occluding thrombus completely closes the lumen of the vessel. A spherical thrombus is freely located in the cavities of the heart, and the dilatation clamp is tightly attached to the walls of the aneurysm.

The thrombus can undergo aseptic autolysis (softening) under the influence of proteolytic enzymes or septic autolysis with the participation of microorganisms, as well as organization - replacement with connective tissue. With a long existence in the thrombus, channels (sewerage) are formed, which are later lined with the endothelium and transformed into vessels (vascularization). Calcification of the thrombus (petrification) often occurs in the veins. Similar formations are called phlebolites. With the severance of the thrombus from the place of its formation, a serious complication develops - thromboembolism . A thrombus that closes the lumen of a blood vessel, especially a large one, causes ischemia of tissues up to their necrosis, for example, myocardial infarction, lung, kidney.