Embolus Health Dictionary

Surgical removal of a clot or EMBOLUS to clear an obstruction in an artery (see ARTERIES, DISEASES OF). The obstruction may be cleared by inserting a balloon (Fogarty) catheter (see CATHETERS) into the blood vessel or by surgical incision through the arterial wall. Embolectomy may be a life-saving operation when a patient has a PULMONARY EMBOLISM.... embolectomy

The plugging of a small blood vessel by an EMBOLUS which has been carried through the larger vessels by the bloodstream. It is due usually to fragments of a clot which has formed in some vessel, or to small portions carried o? from the edge of a heart-valve when this organ is diseased. However, the plug may also be a small mass of bacteria, or a fragment of a tumour, or even a mass of air bubbles sucked into the veins during operations on the neck. The result is usually more or less destruction of the organ or part of an organ supplied by the obstructed vessel. This is particularly the case in the BRAIN, where softening of the brain, with APHASIA or a STROKE, may be the result. If the plug is a fragment of malignant tumour, a new growth develops at the spot; if it is a mass of bacteria, an ABSCESS forms there. Air-embolism occasionally causes sudden death in the case of wounds in the neck, the air bubbles completely stopping the ?ow of blood. Fat-embolism is a condition which has been known to cause death

– masses of fat, in consequence of such an injury as a fractured bone, ?nding their way into the circulation and stopping the blood in its passage through the lungs. (See also PULMONARY EMBOLISM.)... embolism

The condition in which an embolus (see EMBOLISM), or clot, is lodged in the LUNGS. The source of the clot is usually the veins of the lower abdomen or legs, in which clot formation has occurred as a result of the occurrence of DEEP VEIN THROMBOSIS (DVT) – THROMBOPHLEBITIS (see VEINS, DISEASES OF). Thrombophlebitis, with or without pulmonary embolism, is a not uncommon complication of surgical operations, especially in older patients. This is one reason why nowadays such patients are got up out of bed as quickly as possible, or, alternatively, are encouraged to move and exercise their legs regularly in bed. Long periods of sitting, particularly when travelling, can cause DVT with the risk of pulmonary embolism. The severity of a pulmonary embolism, which is characterised by the sudden onset of pain in the chest, with or without the coughing up of blood, and a varying degree of SHOCK, depends upon the size of the clot. If large enough, it may prove immediately fatal; in other cases, immediate operation may be needed to remove the clot; whilst in less severe cases anticoagulant treatment, in the form of HEPARIN, is given to prevent extension of the clot. For some operations, such as hip-joint replacements, with a high risk of deep-vein thrombosis in the leg, heparin is given for several days postoperatively.... pulmonary embolism

Bloodlessness of a part of the body, due to contraction, spasm, constriction or blocking (by EMBOLUS or by THROMBUS) of the arteries: for example, of the heart.... ischaemia

An imaging procedure that enables blood vessels to be seen clearly on X-ray film following the injection of a contrast medium (a substance

that is opaque to X-rays). Angiography is used to detect conditions that alter the appearance of blood vessels, such as aneurysm, and narrowing or blockage of blood vessels by atherosclerosis, or by a thrombus or embolus. It is also used to detect changes in the pattern of blood vessels that supply organs injured or affected by a tumour.

Carotid angiography (of the arteries in the neck) may be used to investigate transient ischaemic attacks. Cerebral angiography can be used to detect an aneurysm in the brain or pinpoint the position of a brain tumour. Coronary angiography, often combined with cardiac catheterization, can identify the sites of narrowing or blockage in coronary artery disease. Digital subtraction angiography uses computer techniques to process images and remove unwanted background information.

Angiographic techniques have been adapted to allow certain treatments that, in some cases, eliminate the need for surgery (see angioplasty, balloon; embolization). (See also aortography.)... angiography

The deliberate obstruction of a blood vessel in order to stop

internal bleeding or to cut off the blood supply to a tumour. In the latter case, the technique can relieve pain; cause the tumour to shrivel, making surgical removal easier; or stop the tumour from spreading. Embolization can also be used to block flow through vascular abnormalities such as haemangiomas both in the skin and the internal organs. A catheter is introduced into a blood vessel near the one to be blocked and the embolus that will block the vessel is released through the catheter. Emboli are made of materials such as bloodclotting agents or silicone.... embolization

The removal of a thrombus that is blocking a blood vessel. It is performed as an emergency procedure if a major artery is blocked, or as a precautionary measure if there is a risk of an embolus breaking off. Before surgery, the site of the thrombus is established by angiography and the patient may be given anticoagulant drugs.... thrombectomy

The blockage of a blood vessel by a piece of a blood clot (embolus) that has broken off from a thrombus elsewhere in the circulation.

(See also thrombosis; embolism).... thromboembolism

n. an incision into, or a needle puncture of, the wall of an artery. This is most often performed as a diagnostic procedure in the course of *arteriography or cardiac *catheterization. It may also be required to remove an embolus (see embolectomy).... arteriotomy

n. the death of part or the whole of an organ that occurs when the artery carrying its blood supply is obstructed by a blood clot (thrombus) or an *embolus. For example, *myocardial infarction, affecting the muscle of the heart, follows coronary thrombosis. A small localized area of dead tissue produced as a result of an inadequate blood supply is known as an infarct. Infarcts also arise when venous outflow from an organ or tissue is obstructed, as occurs when the ovary or testis twist on their vascular pedicles (stalks), or when the sigmoid colon twists in *volvulus.... infarction

impairment of the blood flow to the arteries that supply the small and large intestine. The arteries include the *coeliac axis and the superior and inferior mesenteric arteries. Partial or total occlusion of blood flow may occur abruptly or over a protracted period (acute vs. chronic mesenteric ischaemia). Causes of an acute episode include migration of an arterial blood clot or embolus into the mesenteric vessels, an arterial blood clot in patients with atherosclerosis, profound low blood pressure, or states promoting coagulation. Typically a patient presents with severe abdominal pain, nausea and vomiting, diarrhoea, and rectal bleeding. Rapid diagnosis is essential since impaired intestinal blood flow predisposes to the development of gangrene and necrosis of the bowel. Treatment includes aggressive fluid resuscitation, pain relief, antibiotics, surgical resection of nonviable bowel, and radiological or surgical *revascularization of implicated arteries. In chronic mesenteric ischaemia, abdominal pain precipitated by eating is the main symptom, often accompanied by loss of appetite and marked weight loss.... mesenteric ischaemia