AORTIC ARCH SYNDROME

group of disorders that cause blockage of the vessels that branch off from the aorta in the area in which the aorta arches over the heart. The aorta is the principal vessel through which the heart pumps oxygen-rich blood into the systemic circulation. The aortic branches that may be affected supply blood to the head, the neck, the arms, and part of the body wall. Most often the condition occurs in middle-aged or elderly persons and is caused by atherosclerosis, in which fatty plaques form in the artery lining. A rare form of the aortic arch syndrome that primarily affects Oriental women is called Takayasu's disease, or nonspecific arteritis (also called pulseless disease). The progressive blockage causes impaired cerebral circulation, which can lead to blindness and paralysis. Most deaths from the disease result from damage to the heart muscle and to the brain. Treatment involves bypass grafting. Congenital defects of the aortic arch include persistent ductus arteriosus, in which the channel connecting the aorta and the pulmonary artery in the fetus does not close after birth and must be closed surgically, and coarctation (narrowing) of the aorta, which causes an increased work load on the left ventricle.