Brachiocephalic artery

Brachiocephalic artery

Schematic of the proximal aorta, frontal view. The brachiocephalic artery (labeled innominate) is the third branch of the aorta and the first branch from the arch of the aorta. The heart in the lower left is not shown.

The veins of the thyroid gland.
Details
Latin truncus brachiocephalicus
Source
 aortic arch
Branches
 right common carotid artery
right subclavian artery
thyroid ima artery
brachiocephalic vein
Identifiers
Gray's p.548
MeSH A07.231.908.130
Dorlands
/Elsevier		 t_20/12825973
TA A12.2.04.004
FMA 3932
Anatomical terminology

The brachiocephalic artery (or brachiocephalic trunk or innominate artery) is an artery of the mediastinum that supplies blood to the right arm and the head and neck.

It is the first branch of the aortic arch, and soon after it emerges, the brachiocephalic artery divides into the right common carotid artery and the right subclavian artery.

There is no brachiocephalic artery for the left side of the body. The left common carotid, and the left subclavian artery, come directly off the aortic arch. However, there are two brachiocephalic veins.

Structure

It arises, on a level with the upper border of the second right costal cartilage, from the commencement of the arch of the aorta, on a plane anterior to the origin of the left carotid; it ascends obliquely upward, backward, and to the right to the level of the upper border of the right sternoclavicular articulation, where it divides into the right common carotid and right subclavian arteries. The artery then crosses the trachea in front of it obliquely from the left to the right, roughly at the middle of the trachea or the level of the ninth tracheal cartilage.

In infants, it often divides cephalad to the sternoclavicular articulation, within the anterior triangle of the neck.

Branches

The thyreoidea ima (a. thyreoidea ima) ascends in front of the trachea to the lower part of the thyroid gland, which it supplies.

Variation

The innominate artery usually gives off no branches, but occasionally a small branch, the thyreoidea ima, arises from it. Other times, it gives off a thymic or bronchial branch.

It varies greatly in size, and appears to compensate for deficiency or absence of one of the other thyroid vessels. It occasionally arises from the aorta, the right common carotid, the subclavian or the internal mammary.

Additional images

References

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

    External links