Less common than abdominal aortic aneurysms (0.16% vs 4%). Most common in 50-60-year-olds with male predominance (3:1). Normal aortic diameter varies by age, sex, and body surface area
AAA affects 7.5% of patients over 65 years. Risk increases with aneurysm diameter: 9-33% rupture rate at ≥7 cm. 26% of AAA reaching 8 cm rupture within 6 months
Bicuspid aortic valve has two unequal-sized functional leaflets. Congenital form occurs in ~2% of population, more common in males. Acquired form results from fibrous fusion between trileaflet valves
AAA is focal dilatation of abdominal aorta >3 cm or 50% greater than normal. Affects 10% of patients over 65 years, 4:1 male/female ratio. Most common cause of death in Western world
AAA rupture is crucial in patients with acute abdominal pain. Primary signs include periaortic stranding, retroperitoneal hematoma, and contrast extravasation. Most cases show posterior periaortic hemorrhage. Massive hemorrhage commonly affects posterior pararenal and perirenal compartments
Abdominal aorta starts at heart's left ventricle and runs down abdomen. Begins below diaphragm at T12 level and ends above pelvis. Narrows to about 2 centimeters width in abdomen. Contains three layers: intima, media, and adventitia