The aorta, the largest artery in the body, transports oxygen rich blood from the left ventricle of the heart to the rest of the body. As it emerges from the left ventricle of the heart, the aorta has the shape of a walking cane, with an ascending part, an arch, and a descending part that travels through the chest and continues into the abdomen. From the aorta, branches to the head, arms, chest, abdomen, and legs supply the body with oxygen and nutrients.
An aortic aneurysm is a dilation, bulging, or ballooning of a weakened part of the aortic artery wall. The normal pressure of blood from the pumping of the heart causes the weakened portion of the aorta to slowly stretch and bulge, leading to the formation of an aneurysm. Aortic aneurysms are named according to their location:
- thoracic aortic aneurysms are those that form in the chest cavity
- thoracoabdominal aneurysms extend from the chest into the abdomen
- abdominal aortic aneurysms occur exclusively in the abdominal portion of the aorta
Regardless of their location, aortic aneurysms are dangerous because of the risk that they will rupture, causing life-threatening hemorrhage.