Aortic Aneurysm – Diagnosis | NHLBI, NIH

To diagnose an aortic aneurysm, your healthcare provider will do a physical exam and an imaging test. An abdominal aortic aneurysm is diagnosed when your abdominal aorta is three centimeters or greater in diameter. The normal diameter of the thoracic aorta depends on your age, your sex, and which part of the thoracic aorta is measured.