The brachiocephalic trunk (or brachiocephalic artery 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.
It arises, on a level with the upper border of the second right costal cartilage, from the start of the aortic arch, on a plane anterior to the origin of the left carotid artery; 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.