Transesophageal echocardiography (TEE) is a valuable means of assessing diseases of the thoracic aorta. The portion of descending aorta between the left subclavian artery proximally and the ligamentum arteriosum distally is known as the aortic isthmus. A number of the branches of the aorta can be imaged using TEE. Coarctation of the aorta may present as a partial narrowing, or rarely a complete occlusion, of the aorta. The ductus arteriosus connects the pulmonary artery to the aorta in the fetal circulation. Supravalvular aortic stenosis is a narrowing of the aorta usually at the level of the border of the sinus of Valsalva. The etiology of a true aortic aneurysm has much in common with aortic dissection. True tumors of the aorta, including leiomyosarcoma, fibroelastoma, and epithelioma, are fortunately extremely rare. Traumatic injury to the aorta usually occurs as a result of rapid deceleration injury or blunt chest trauma.