aneurysm


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Related to aneurysm: stroke, aortic aneurysm, abdominal aortic aneurysm, Brain Aneurysm

aneurysm

(ăn`yo͝orĭzəm), localized dilatation of a blood vessel, particularly an arteryartery,
blood vessel that conveys blood away from the heart. Except for the pulmonary artery, which carries deoxygenated blood from the heart to the lungs, arteries carry oxygenated blood from the heart to the tissues.
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, or the heartheart,
muscular organ that pumps blood to all parts of the body. The rhythmic beating of the heart is a ceaseless activity, lasting from before birth to the end of life. Anatomy and Function

The human heart is a pear-shaped structure about the size of a fist.
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. Dilatation of an artery, and therefore weakness of that portion of the arterial wall, may be rarely congenital, or it may be caused by syphilissyphilis
, contagious sexually transmitted disease caused by the spirochete Treponema pallidum (described by Fritz Schaudinn and Erich Hoffmann in 1905). Syphilis was not widely recognized until an epidemic in Europe at the end of the 15th cent.
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, hypertensionhypertension
or high blood pressure,
elevated blood pressure resulting from an increase in the amount of blood pumped by the heart or from increased resistance to the flow of blood through the small arterial blood vessels (arterioles).
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 (high blood pressure), arteriosclerosisarteriosclerosis
, general term for a condition characterized by thickening, hardening, and loss of elasticity of the walls of the blood vessels. These changes are frequently accompanied by accumulations inside the vessel walls of lipids, e.g.
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, bacterial and fungal infections, or penetrating injury as from a bullet or knife. An aneurysm may be asymptomatic or it may cause varying symptoms, depending upon its location and size and on whether the expanding mass is pressing on adjacent nerves or vital organs. The weakened arterial walls of an aneurysm are always in danger of sudden rupture, with resulting hemorrhage and death.

Aneurysms occur most commonly in the large arteries; the aortaaorta
, primary artery of the circulatory system in mammals, delivering oxygenated blood to all other arteries except those of the lungs. The human aorta, c.1 in. (2.54 cm) in diameter, originates at the left ventricle of the heart.
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, the largest vessel in the body, is the one most often affected. Ventricular aneurysms of the heart often occur after myocardial infarctionsinfarction,
blockage of blood circulation to a localized area or organ of the body resulting in tissue death. Infarctions commonly occur in the spleen, kidney, lungs, brain, and heart.
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. Aneurysms also occur in the arteries within the skull and in other areas of the body.

Aneurysms can be detected by echocardiogram, spin echo magnetic resonance imaging scans, coronary arteriograms, and biplane ventriculograms. Treatment, where feasible, may involve surgery to remove the aneurysm or the insertion of coiled wire to close it off. Coiled wire can only be used on aneurysms that are connected to the blood vessel by a narrowed neck. The coiling fills the aneurysm, obstructing the flow of blood into the dilatation, and blood clots form around the wire, preventing the aneurysm from bursting. Surgical excision of the dilated saclike portion of the affected artery sometimes requires the replacement of that portion by a synthetic graft, a section of vessel (made of polymer fiber) that is similar in size.

aneurysm

[′an·yə‚riz·əm]
(medicine)
Localized abnormal dilation of an artery due to weakening of the vessel wall.

aneurysm

, aneurism
a sac formed by abnormal dilation of the weakened wall of a blood vessel
References in periodicals archive ?
Case of aneurysm, seated on an abnormal main artery of the lower limb.
Gadolinium contrast material mixes poorly with stagnant aneurysm blood, producing a "layered gadolinium sign.
This presentation on Aneurysms and PKD is part of an ongoing series of two-hour informational support meetings hosted by the Hamilton Chapter of The PKD Foundation of Canada.
Mr Alok Tiwari, consultant vascular surgeon at the QE, said: "A lot of people don't know they have an aneurysm until it bursts and they either die from it or need an emergency operation.
This is an important recommendation because evidence now exists that screening high-risk men for abdominal aortic aneurysms can reduce deaths from aneurysm," Task Force chairman Dr.
The diagnostic and treatment algorithms for DPA aneurysm are not well established, because the disease is rare.
For the latest study, experts asked 60 women with intact brain aneurysms about their use of the oral contraceptive pill and hormone replacement therapy (HRT).
The cPAX Aneurysm Treatment System was approved on April 1, 2011, under a Humanitarian Device Exemption (HDE).
One is to look at the natural history of ruptured aneurysms in which a group of patients is followed over time.
The median age of patients who had a thoracic aneurysm was 76 years, compared with 74 years for those who did not, he said.
Rupture of the aneurysm occurs when the intra-luminal pressure exceeds the tensile strength of the wall.