Ascending Aortic Aneurysm

Aortic aneurysm is commonly defined as a localized, permanent aortic dilation diameter of 50% or greater than normal, and is contained by all the layers of the normal aortic wall. Degeneration of the elastic media is the most common biologic cause of aneurysm formation, but congenital syndromes such as bicuspid aorta disease, Marfan syndrome, Ehlers–Danlos syndrome and Loeys–Dietz syndrome, as well as infectious and noninfectious inflammatory syndromes are additional causes. Ascending aortic aneurysms are commonly asymptomatic, and are frequently discovered incidentally on radiographic studies. The advancement of echocardiography, computed tomography (CT), and magnetic resonance imaging (MRI) have allowed for many options for radiologic assessment. Prompt surgical evaluation and intervention is indicated in patients with symptoms suggestive of aneurysm expansion independently of size, except in cases of limited life expectancy or quality of life from comorbid conditions. For asymptomatic adults with degenerative thoracic aneurysms, it is generally accepted that resection of the ascending aortic aneurysm is indicated at 5.5 cm or growth rate of more than 0.5 cm/year, aortic arch aneurysms should be resected at 5.5 cm, and descending aortic aneurysms may be monitored until a diameter of 6.0 cm prior to open repair. Surgical thresholds for repair of ascending aortic aneurysms are smaller when caused by genetic syndromes.