White thrombi

The white thrombus is composed of platelets and fibrin and is relatively poor in erythrocytes. It forms at the site of an injury or abnormal vessel wall, particularly in areas where blood flow is rapid (arteries). 

The platelet is central to normal hemostasis and to all thromboembolic disease. A white thrombus forms initially in high-pressure arteries by adherence of circulating platelets to areas of abnormal endothelium as described above. The growing thrombus of aggregated platelets reduces arterial flow. This localized stasis triggers fibrin formation, and a red thrombus forms around the nidal white thrombus. 

A red thrombus can form around a white thrombus as mentioned above or de novo in low-pressure veins, initially by adherence of platelets (as in arteries) but followed promptly by the process of blood coagulation so that the bulk of the thrombus forms a long tail consisting of a fibrin network in which red cells are enmeshed. These tails become detached easily and travel as emboli to the pulmonary arteries. Such emboli often arise from a deep venous thrombosis (DVT)—a thrombus in the veins of the legs or pelvis. Although all thrombi are mixed, the platelet nidus dominates the arterial thrombus and the fibrin tail the venous thrombus. Arterial thrombi cause serious disease by producing local occlusive ischemia venous thrombi, by giving rise to distant embolization. 

Since anticoagulants such as heparin and vitamin k antagonists have not been found to effectively control arterial thrombosis, the main attention for the past 15 years has been to study platelet function and develop compounds to control the role of the platelet in arterial thrombosis, mainly through the control of platelet aggregation or white thrombus formation. The greatest advance in the last several years has been the discovery, structure determination and biological character-... 

Platelet adhesion to vessel walls and the subsequent release of adenosine diphosphate (ADP) initiates the formation of the arterial (white) thrombus. The arterial thrombus grows as platelets aggregate. As the thrombus occludes blood flow, it is surrounded by a "red" clot, composed of fibrin, platelets and erythrocytes. Like atherosclerotic plaques, arterial thrombi occlude blood vessels, causing tissue ischemia. 

Irreversible permanent clot (white thrombus) Red thrombus... 

Rodman, N., Mason, R., Brinkhous, K. Some pathogenic mechanisms of white thrombus formation Agglutination and self-destruction of the platelet. Fed. Proc. 22, 1356-1365 (1963)... 

Thrombosis is the development of a thrombus , consisting of platelets, fibrin, red and white blood cells in the arterial or venous circulation. Platelet-rich white thrombi are found in the arterial system and can be prevented by antiplatelet drugs. 

A thrombus is a mass of cells and protein composed principally of platelets and fibrin, but also containing red and white blood cells. A thrombus which forms in the circulatory system can become occlusive in that the thrombus can physically block flowing blood. 

There are several techniques available for mechanical thrombolysis. The most common is probing the thrombus with a microguidewire. This technique appears to be useful in facilitating chemical thrombolysis. Alternatively, a snare (e.g., Amplatz Goose-Neck Microsnare, Microvena, White Bear Lake, MN) can be used for multiple passes through the occlusion to disrupt the thrombus. " A snare can also be used for clot retrieval, mostly in simations in which the clot has a firm consistency or contains solid material. ... 

Venous thromboembolism (VTE) results from clot formation in the venous circulation and is manifested as deep vein thrombosis (DVT) and pulmonary embolism (PE). A DVT is a thrombus composed of cellular material (red and white blood cells, platelets) bound together with fibrin strands. A PE is a thrombus that arises from the systemic circulation and lodges in the pulmonary artery or one of its branches, causing complete or partial obstruction of pulmonary blood flow. 

ICAM-1, ICAM-2) and vascular cell adhesion molecule (VCAM). Platelets are attracted to damaged endothelium where they adhere to prevent blood loss in a similar fashion to white blood cells, i.e. via adhesion molecule interactions, to form a clot (thrombus). 

White clot syndrome - Rarely, patients may develop new thrombus formation in association with thrombocytopenia resulting from irreversible aggregation of platelets induced by heparin, the so-called white clot syndrome. The process may lead to severe thromboembolic complications. Monitor platelet counts before and during therapy. If significant thrombocytopenia occurs, immediately... 

Arterial thrombi (white thrombi) are formed initially from both platelets and fibrin in medium-sized arteries on the basis of atherosclerosis. These thrombi can lead to symptoms of, among others, myocardial ischemia and myocardial infarction. The treatment is primarily aimed at prevention of thrombus formation with platelet aggregation inhibitors. For the treatment of myocardial infarction thrombolytic agents are used and for secondary prevention both oral anticoagulants and anti-platelet drugs are employed. 

Pathophysiologically, occlusion in these high-flow areas comprises primarily consecutive layers of adherent platelets - the white head thrombus. 

Delayed endothelial healing. In case 1, a smooth, white lesion was detected at three and nine months. In case 2, erosion with a superficial thrombus was seen at three months. At nine months, the erosion had disappeared, although an uncovered stent was observed. In case 3, severe, circumferential erosion with superficial thrombus was detected at three months, with erosion still evident but partly improved at nine months. These results suggest that the healing process was not completed nine months after brachytherapy. Source From Ref. 73. 

Some white cells and mural thrombus were also observed. It that there were no stent thromboses nor significant differ-... 

Embolization of plaque debris or thrombus may block a more distal vessel. Emboli are usually the cause of obstruction of the anterior circulation intracranial vessels (Lhermitte et al. 1970 Ogata et al. 1994), at least in white males in whom intracranial disease is relatively rare. Since emboli follow the prevailing direction of flow in a vessel, most emboli... 

Occurrence (Roe 2005, Scholte 2006) Type of occlusion and thrombus 30%-50% - Usually complete occlusion Red 50%-70% - Non-complete occlusion - White... 

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