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Related to Thrombus: thrombi, mural thrombus


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 ?
In conclusion, this report provides everything a prospective dealmaker needs to know about partnering in the research, development and commercialization of thrombus technologies and products.
Tumor thrombus can be caused by primary tumor arising from the vessel wall as in leiomyosarcoma or by extension from an adjacent organ--most commonly in renal cell carcinoma, hepatocellular carcinoma, adrenocortical carcinoma, or retroperitoneal metastasis.
Treatment of neonatal thrombus formation with recombinant tissue plasminogen activator: six years experience and review of the literature.
This gave excellent visualization of the origins of the subsegmental arteries, and allowed removal of all visible thrombus with the exception of the left lower lobe and lingual.
We found occult caval thrombus in 60% of patients ultimately diagnosed with DVT.
However, there are still serious concerns over the loss of thrombus during clot retrieval.
Intraluminal thrombus and bowel obstruction in acute leukemia due to bleeding Meckel's diverticulum.
This leaves us with high expectations that the MASTER trial will confirm the benefits of MGuard for thrombus laden lesions in a randomized fashion.
Minneapolis, Minnesota) is a catheter-based system that uses high-velocity saline jets to produce a vacuum for thrombus aspiration and extraction.
In April 2007, the FDA approved Possis' AngioJet Spiroflex VG rapid exchange catheter for thrombus removal in coronary conduits.
Although the exact mechanism of thrombus formation in sarcoidosis is not yet known, venous stasis secondary to lymph node compression, local tissue thrombophilia in involved organs, and granulomatous phlebitis are potential mechanisms.