aortic arch

n.
One of a series of paired arteries in a vertebrate embryo that connects the ventral arterial system to the dorsal arterial system.

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.

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

• a. a. anomalies — include persistent right aortic arch, double aortic arch, and anomalous arch arteries, which cause compression of areas of the respiratory or digestive tracts.
• a. a. 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 a. a. — persistence of both right and left embryonic aortic arches creating a vascular ring anomaly that causes esophageal entrapment.
• persistent right a. a. — 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.
• a. a.–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.
• a. a. 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.
• a. a. 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.
• a. a. 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.

Note: click on a word meaning below to see its connections and related words.

The noun has one meaning:

Meaning #1: the part of the aorta that arches and turns downward

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