The aorta, the body's largest artery, extends from the aortic valve in the chest to the midabdomen, where it bifurcates into the common iliac arteries. Along its course the aorta is divided anatomically into thoracic and abdominal components. The thoracic aorta is further subdivided into the ascending, arch, and descending segments and the abdominal aorta into the suprarenal and infrarenal segments.

The ascending thoracic aorta has two distinct portions. The lower …