aortic arch

aortic arch

n.

1. The curved portion between the ascending and descending portions of the aorta, lying behind the manubrium and giving rise to the brachiocephalic trunk, the left common carotid, and the left subclavian arteries. Also called arch of aorta.

2. Any of several pairs of arterial channels encircling the embryonic pharynx in the mesenchyme of the branchial arches.

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aortic arch (AA).

See arch of the aorta.

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aortic arch

the curvature of the aorta where it turns from its cranial path to a caudal one and becomes the thoracic aorta. See also aortic.

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aortic arch anomalies

include persistent right aortic arch, double aortic arch, and anomalous arch arteries, which cause compression of areas of the respiratory or digestive tracts.

aortic arch branching patterns

differ between species; e.g. cat, dog, rabbit are the same; horses and cattle are the same; pigs have one pattern, chickens another.

double aortic arch

persistence of both right and left embryonic aortic arches creating a vascular ring anomaly that causes esophageal entrapment.

persistent right aortic arch

persistence of the fourth right aortic arch causes constriction of the esophagus with regurgitation, aspiration pneumonia and dysphagia, and bloat in ruminants. The signs are present at birth.

aortic arch-pulmonary artery fistula

recorded rarely in horses; a fistula develops after simultaneous perforations occur in the pulmonary artery and the aorta resulting in the development of a fistula and the acute onset of heart failure which is usually fatal within a few days. Possibly results from an inherited defect in the vasa vasorum of the vessels.

aortic arch rupture

rare occurrence in horses resulting in acute cardiac tamponade or dissecting aneurysm into the myocardium and sudden death; is part of marfan's syndrome in calves; rarely a result of onchocerciasis in cattle.

aortic arch syndrome

any of a group of disorders leading to occlusion of the arteries arising from the aortic arch; such occlusion may be caused by atherosclerosis, arterial embolism, etc.

aortic arch transformation

the change in the original pattern of aortic arches of the fetus as a result of degeneration of some vessels and differential enlargement of others (see Table 9).