the formation of blood clots during life in the lumen of a blood vessel or in the heart.
Thrombogenesis is promoted by injury to the vascular wall owing to atherosclerosis or inflammation, by the slowing of the blood flow, and by an increase in the coagulability and viscosity of the blood. Peripheral venous thrombosis is most common; thrombosis in the arterial system occurs less frequently. Arterial thrombosis interferes with the blood supply to areas of tissue and often leads to necrosis of such tissue. For example, coronary thrombosis results in myocardial infarction, and cerebral thrombosis, in a stroke, or cerebrovascular accident. The thrombus may subsequently either dissolve (undergo lysis), with partial or complete restoration of the blood vessel’s patency, or it may become thickened (organized). Multiple capillary thrombosis, a syndrome involving disseminated intravascular blood coagulation, is often combined with an increased tendency for tissues to bleed. The condition may develop during shock, hemorrhage, or severe infectious diseases, or it may be a manifestation of intolerance for drugs.
Biochemical and roentgenological methods of examination are used to diagnose thrombosis. Treatment includes the administration of anticoagulants, antispasmodics, and fibrinolytic and anti-inflammatory agents, as well as surgical removal of the thrombus.
A. N. SMIRNOV and V. D. TOPOLIANSKII