Arch, aortic

The aortic arch is the second section of the aorta, the largest artery in the body. The aorta arises from the left ventricle of the heart and first goes up, then bends, and goes down. The part that goes up is termed the ascending aorta, the part that bends is the arch of the aorta, and the part that goes down is the descending aorta. The aortic arch gives off, in order, the brachiocephalic trunk and the left common carotid and subclavian arteries. The brachiocephalic trunk, the first branch off of the aortic arch, subsequently splits to form the right subclavian and the right common carotid arteries that supply blood to the right arm and right side of the neck and head. (Brachio- = arm; and -cephalic = head). The left common carotid artery and left subclavian artery, the second and third branches off of the aortic arch, perform parallel functions on the left side. Like the other sections of the aorta, the aortic arch is an arbitrary anatomic entity. The aorta is one continuous conduit that stems from the left ventricle of the heart to carry blood to most of the body. The arch of the aorta is nonetheless a hallowed and convenient subdivision of the aorta. In anatomy, an arch is any structure with a curved or bowlike contour, that bends, like the arch of the aorta.