The body’s main artery, which supplies oxygenated blood to all other parts. The aorta arises from the left ventricle (the main pumping chamber of the heart) and arches up over the heart
before descending, behind it, through the chest cavity. It terminates in the abdomen by dividing into the 2 common iliac arteries of the legs.
The aorta is thick-walled and has a large diameter in order to cope with the high pressure and large volume of blood passing through it. (See also arteries, disorders of; circulatory system.)
The large vessel which opens out of the left ventricle of the HEART and carries blood to all of the body. It is about 45 cm (1••• feet) long and 2·5 cm (1 inch) wide. Like other arteries it possesses three coats, of which the middle one is much the thickest. This consists partly of muscle ?bre, but is mainly composed of an elastic substance called elastin. The aorta passes ?rst to the right, and lies nearest the surface behind the end of the second right rib-cartilage; then it curves backwards and to the left, passes down behind the left lung close to the backbone, and through an opening in the diaphragm into the abdomen. There it divides, at the level of the navel, into the two common iliac arteries, which carry blood to the lower limbs.
Its branches, in order, are: two coronary arteries to the heart wall; the brachiocephalic, left common carotid, and left subclavian arteries to the head, neck and upper limbs; several small branches to the oesophagus, bronchi, and other organs of the chest; nine pairs of intercostal arteries which run around the body between the ribs; one pair of subcostal arteries which is in series with the intercostal arteries; four (or ?ve) lumbar arteries to the muscles of the loins; coeliac trunk to the stomach, liver and pancreas; two mesenteric arteries to the bowels; and suprarenal, renal and testicular arteries to the suprarenal body, kidney, and testicle on each side. From the termination of the aorta rises a small branch, the median sacral artery, which runs down into the pelvis. In the female the ovarian arteries replace the testicular.
The chief diseases of the aorta are ATHEROMA
and ANEURYSM. (See ARTERIES, DISEASES OF; COARCTATION OF THE AORTA.)
n. (pl. aortae or aortas) the main artery of the body, from which all others derive. It arises from the left ventricle (ascending aorta), arches over the top of the heart (see aortic arch) and descends in front of the backbone (descending aorta), giving off large and small branches and finally dividing to form the right and left *iliac arteries. The part of the descending aorta from the aortic arch to the diaphragm is called the thoracic aorta; the part below the diaphragm is the abdominal aorta. —aortic adj.
A narrowing of the AORTA in the vicinity of the insertion of the ductus arteriosus. It is a congenital abnormality but may not be discovered until well into childhood or adolescence. The diagnosis is easily made by discovering a major di?erence between the blood pressure in the arms and that of the legs. If untreated it leads to hypertension and heart failure, but satisfactory results are now obtained from surgical treatment, preferably in infancy. Paediatricians screen for coarctation by feeling for femoral pulses, which are absent or weak in this condition.... coarctation of the aorta
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