Aorta is largest artery in body with three layers: intima, media, and adventitia. Normal aortic dimensions correlate strongly with age and body size. Aortic root diameter measured perpendicular to proximal aorta axis. Normal upper limit is 2 SDs above predicted mean diameter
Affects approximately 2% of US adults, increasing with age. Divided into acute and chronic forms. Can be primary (degenerative) or secondary (functional)