About the Aorta
The Aorta and Its Structure
The aorta is the largest artery in the body. It rises from the heart's major pumping chamber, the left ventricle and supplies oxygen-rich blood from the heart to the rest of the body. When the aorta is diseased or compromised it puts all other organ systems at risk.
Aortic root – The aorta begins at the root. Starting from the aortic valve (annulus) and becoming slightly wider in diameter (sinuses of Valsalva), it gives rise to two coronary arteries and ends at the beginning of the ascending aorta (sinotubular junction). The two coronary arteries are responsible for carrying oxygen-rich blood to the heart muscle itself.
Ascending aorta - Extends upward from the aortic root to the point where the innominate artery branches off the aorta, and the aorta begins to form an arch. It is within the heart sack (pericardium) by itself and has no branching arteries. There is little support from surrounding tissue and must therefore handle the entire cardiac output volume (minus the coronary arteries). The ascending segment is the most vulnerable part of the aorta.
Aortic arch - Represents the curved portion at the top of the aorta. The innominate, left common carotid, and left subclavian arteries supply blood to the head and upper body, and branch from the arch. The aortic arch is outside the pericardial sack and has better support from surrounding structures.
Descending aorta - This section begins just beyond the arch as the aorta bends down into the body and ends at the diaphragm. It contains the arteries that feed the spinal cord.
Thoracoabdominal aorta - It begins at the diaphragm and ends at the celiac, superior mesenteric and renal arteries which are known as the visceral vessels.
Abdominal aorta – This segment begins below the renal arteries, which supply blood to the kidneys, and ends where it divides into the two iliac arteries. It contains a small artery named the inferior mesenteric artery.