- Aortic arch
- 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.
* * *aortic arch n1) one of the arterial branches in vertebrate embryos that exist in a series of pairs with one on each side of the embryo, that connect the ventral arterial system lying anterior to the heart to the dorsal arterial system above the alimentary tract, and that persist in adult fishes but are reduced or much modified in the adult of higher forms2) ARCH OF THE AORTA
* * *that part of the aorta that extends from the ascending aorta, upward over the heart and then backward and down as far as the fourth thoracic vertebra. stretch receptor in its outer wall monitor blood pressure and form part of the system maintaining this at a constant level.
* * *1. arcus aortae. 2. any of a group of paired vessels arching from the ventral to the dorsal aorta through the branchial arches of fishes and the pharyngeal arches of amniote embryos. In mammalian development, arches 1 and 2 disappear; arch 3 joins the common to the internal carotid; the left arch 4 remains as the arch of the definitive aorta while the right arch 4 joins the aorta to the subclavian artery; arch 5 is absent or disappears; and the ventral halves of arch 6 form the pulmonary arteries while the connections to the dorsal aorta are lost, although the left half, or ductus arteriosus, serves as an arterial shunt until birth.
Medical dictionary. 2011.