aortic arch

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

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.

The noun has one meaning:

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

Artery: Aortic arch
Plan of the branches.
The arch of the aorta, and its branches.
Latin	arcus aortae
Gray's	subject #142 547
Source	ascending aorta
Branches	brachiocephalic artery, left common carotid artery, left subclavian artery
Precursor	fourth aortic arch
MeSH	Aortic+Arch
Dorlands/Elsevier	a_58/12150514

For the embryological structure, see Aortic arches.

The arch of the aorta (Transverse Aorta) begins at the level of the upper border of the second sternocostal articulation of the right side, and runs at first upward, backward, and to the left in front of the trachea; it is then directed backward on the left side of the trachea and finally passes downward on the left side of the body of the fourth thoracic vertebra, at the lower border of which it becomes continuous with the descending aorta.

It thus forms two curvatures: one with its convexity upward, the other with its convexity forward and to the left. Its upper border is usually about 2.5 cm. below the superior border to the manubrium sterni.

Relations

The arch of the aorta is covered anteriorly by the pleura and anterior margins of the lungs, and by the remains of the thymus.

As the vessel runs backward its left side is in contact with the left lung and pleura.

Passing downward on the left side of this part of the arch are four nerves; in order from before backward these are, the left phrenic, the lower of the superior cardiac branches of the left vagus, the superior cardiac branch of the left sympathetic, and the trunk of the left vagus.

As the left vagus nerve crosses the arch, it gives off its recurrent branch, which hooks around below the vessel and then passes upward on its right side.

The highest left intercostal vein runs obliquely upward and forward on the left side of the arch, between the phrenic and vagus nerves.

On the right are the deep part of the cardiac plexus, the left recurrent nerve, the esophagus, and the thoracic duct; the trachea lies behind and to the right of the vessel.

Above are the innominate, left common carotid, and left subclavian arteries, which arise from the convexity of the arch and are crossed close to their origins by the left innominate vein.

Below are the bifurcation of the pulmonary artery, the left bronchus, the ligamentum arteriosum, the superficial part of the cardiac plexus, and the left recurrent nerve.

The ligamentum arteriosum connects the commencement of the left pulmonary artery to the aortic arch.

Additional images

Diagram showing the origins of the main branches of the carotid arteries.

Front view of heart and lungs.

Course and distribution of the glossopharyngeal, vagus, and accessory nerves.

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

List of arteries of torso - chest
Pulmonary / coronary	right coronary: SA nodal - AV nodal - atrial - right marginal - posterior interventricular left coronary: anterior interventricular - left circumflex - left marginal
Ascending aorta	aortic arch - brachiocephalic (thyreoidea ima) - common carotid
Subclavian	internal thoracic: anterior intercostal - thymic - pericardiacophrenic - terminal (musculophrenic, superior epigastric) costocervical trunk: highest intercostal (posterior intercostal 1-2) - deep cervical
Descending / thoracic aorta	visceral: bronchial - esophageal - mediastinal parietal: posterior intercostal 3-11 - subcostal - superior phrenic

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