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A blood clot occurring on the wall of a blood vessel where the endothelium is damaged.



a clot of blood formed during the lumen of a blood vessel or in the heart. In a broader sense, extravascular clots of blood that form during bleeding, as well as clots of lymph in the lymphatics are also called thrombi.

The formation of a thrombus consists of the following stages: agglutination of platelets, coagulation of fibrinogen, agglutination of red blood cells, and precipitation of plasma proteins. Thrombi may be white, red, laminated, or hyaline. A white thrombus consists of platelets, fibrin, and white blood cells and is formed slowly during rapid blood flow, generally in arteries. A red thrombus, in which red blood cells predominate, forms rapidly during slow blood flow, generally in veins. The most common type of thrombus is the laminated thrombus, which has a layered structure and crimped surface and contains fragments of white and red thrombi. It is attached to the endothelium of a blood vessel, generally that of a vein; this differentiates it from a postmortem thrombus. A hyaline thrombus forms in blood vessels of the capillary bed and consists of a homogenized mass of protein.

A thrombus may be parietal or obstructive. A parietal thrombus forms within the heart in endocarditis and heart disease, in large arteries in atherosclerosis, and in veins in thrombophlebitis. As a parietal thrombus grows, it becomes obstructive, generally in small arteries and veins. A thrombus that grows rapidly into the lumen of a vessel is called progressive, and one that originates in cardiac insufficiency is called congestive. A thrombus that forms in aneurysms is called dilatational; one that is unattached within an atrium is called spherical. A thrombus can dissolve or can grow connective tissue, a process called organization. Thin-walled blood vessels may appear in this tissue (canalization), or calcium salts may be deposited (calcification). A thrombus may cause an embolism or may become purulent, a condition accompanied by a thrombobacterial embolism and leading to sepsis.


References in periodicals archive ?
The studies are evaluating the medicine for the prevention and treatment of life-threatening blood clots in patients with a wide range of cancer types.
But after closer analysis, it was found that blood clots were a rare side-effect of the combined pill, no matter which brand is used.
Each day, about 274 people lose their lives to deadly blood clots, which is why the National Blood Clot Alliance is so appreciative of the work that the Allscripts Tobacco Road Marathon and its incredible volunteers are doing to help support our efforts to raise awareness about this pressing public health problem," says Teresa Bordeaux, NBCA Board member and resident of Cary, North Carolina.
BB-10153's extended half-life (three to four hours) enables it to persist in the blood as an inactive pro-drug, activated only at fresh or forming blood clots by the thrombin that is localized there.
NEW YORK, March 5, 2015 /PRNewswire-USNewswire/ -- NYU Langone Medical Center has announced the creation of a new multidisciplinary Venous Thromboembolic Disease Center (VTEC) to treat those with life-threatening blood clots.
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The new AngioJet Ultra System includes an advanced microprocessor-based console and family of disposable thrombectomy sets designed to quickly and safely remove blood clots from arteries and veins.
Rowan Foundation and National Blood Clot Alliance Join Forces to Help Prevent Life-Threatening Blood Clots Among Young Women
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Secretary of State Hillary Clinton has a blood clot in a vein located between her brain and her skull, but is expected to make a full recovery, according to a statement from doctors at New York Presbyterian Hospital.
5] However, in patients with concomitant intrabladder blood clot formation and EBR, the urinary catheter is sometimes occluded by clots and thus fails to drain properly.
ISLAMABAD -- Young professionals are doubling their risk of suffering a potentially life threatening blood clot because they sit working for three hours at a time, eat lunch at their desks and then go home and sit on the sofa, a survey has found.