Anatomy of the Aorta in the Chest

The aorta is the body's largest artery, carrying oxygen-rich blood away from the heart as it begins its journey through the circulatory system. It begins just above the aortic valve, rising out of the left ventricle of the heart, and then curves and bends down into the lower body. Other arteries branch off from it to supply blood to various parts of the body. The aortic root, ascending aorta, aortic arch, descending aorta, and thoracoabdominal aorta all are considered part of the thoracic (chest) aorta, and are treated by thoracic aortic specialists. Aortic Root The very beginning of the aorta, which is slightly larger in size, is called the root. The first two arteries that branch off the aorta, the coronary arteries, are found here. It is important to know this, because if surgery is needed on the aortic root, great care is needed in handling the coronary arteries, which supply blood to the heart. An important break through in aortic surgery was the development of the Bentall technique in 1968, which successfully allowed replacement of the aortic root followed by reattachment of the coronary arteries. This technique was later improved by using buttons of aortic tissue to attach the coronary arteries to the Dacron graft (Button Bentall). Ascending Aorta The ascending aorta is that section between the aortic root and the arch. No other arteries branch from it. This part of the aorta is under the most pressure, handles the greatest volume of blood, and also has very little support around it. Aneurysm and dissection are more likely to happen in this part of the aorta in those with bicuspid aortic valve disease and other connective tissue disorders. Aortic Arch The arch is the top of the aorta, where it curves as it bends down toward the lower body. The innominate, left common carotid, and left subclavian arteries, which carry blood to the head and upper body, branch off the arch. Descending Aorta The section of the aorta beginning just beyond the arch and ending at the diaphragm is called the descending aorta. Many little arteries, called the intercostal arteries, branch from this part of the aorta to supply the spinal cord with blood. Thoracoabdominal Aorta The part of the aorta that includes the lower descending aorta passing through the diaphragm and ending at the level of the renal arteries is called the thoracoabdominal aorta. Below this point, the aorta is called the abdominal aorta.