The aorta is an extremely important blood vessel in the body. Sometimes referred to as the aortic artery, this vessel arises from the left ventricle of the heart, in what is called ascending, then arches over before descending through the chest and abdomen, carrying needed oxygenated blood to the body. After the arch, the descending aorta is split into two sections, and these are called the thoracic aorta and the abdominal aorta.
As might be suspected the thoracic aorta section is located in the chest, and is said to arise directly from the aortic arch, though some people include the arch as part of the thoracic section. It runs roughly the length of the body between the fourth and twelfth thoracic vertebrae. In normal arrangement it crosses behind the pulmonary artery and the heart itself, as it makes its trip downward toward the abdomen.
Like many arteries, the thoracic aorta has a number of branches or smaller blood vessels leading off it that help to supply blood and oxygen to a variety of areas in the body. It might be useful to visualize the full aorta as a highway, with many potential exits for blood cells (vehicles of oxygen). Some of the off-ramps or branches for this section of the aorta help send blood cells to the lungs and the outer surroundings of the heart or the pericardium. Branches from the thoracic aorta support the bronchi, which help to get air to the lungs. Much of the wall of the chest, some of the diaphragm, and the esophagus receive blood from these branches.
As the thoracic aorta descends past the twelfth vertebra it becomes the abdominal aorta. This is one continuous motion downward, and the distinctions in names suggest location but not interruption of the bloodflow path. The abdominal section of the blood vessel supplies yet more areas of the body with needed blood.
The highway or freeway metaphor is useful, again, given the structural and fundamental importance of the thoracic aorta. Any interruption in traffic or any medical condition that affects bloodflow is likely to be grave and require fairly immediate or sometimes emergency treatment. Some of the more common illnesses affecting this section of the great blood vessel include aneurysms of varying types.
If weakening occurs in a section of the thoracic aorta it might result in total collapse or dysfunction of the vessel, and this could be devastating. Moreover, an aneurysm in the thoracic section, can affect anything below it, and might have severe effects on the abdominal aorta. Quick repair may be needed to make certain blood cell traffic continues normally.
Sometimes people also develop ulcers in the thoracic aorta, or they may have conditions in the ascending aorta or arch, such as narrowing (stenosis) or dysfunction of valves. Alternately some people experience leakiness or regurgitation. Congenital defects may result in poor functioning of the aorta from early in life, too. While not all of these conditions are medically urgent, they do need to be watched carefully by a physician. Sudden shifts to poor function in any part of the aorta could require surgical repair to restore greater health to the vessel and the parts of the body it serves.