Aneurysms of the ascending aorta are often due to annuloaortic ectasia in the setting of Marfan disease or can be secondary to aortic stenosis, which may be seen in patients with congenital bicuspid valve. Atherosclerotic aneurysms more often involve the aortic arch and descending aorta. Mycotic aneurysms are often saccular in morphology and should be correlated to medical history.