Abdominal aortic aneurysm.

Most abdominal aortic aneurysms (AAAs) are asymptomatic, not detectable on physical examination, and silent until discovered during radiologic testing for other reasons. Tobacco use, hypertension, a family history of AAA, and male sex are clinical risk factors for the development of an aneurysm. Ultrasound, the preferred method of screening, is cost-effective in high-risk patients. Repair is indicated when the aneurysm becomes greater than 5.5 cm in diameter or grows more than 0.6 to 0.8 cm per year. Asymptomatic patients with an AAA should be medically optimized before repair, including institution of beta blockade. Symptomatic aneurysms present with back, abdominal, buttock, groin, testicular, or leg pain and require urgent surgical attention. Rupture of an AAA involves complete loss of aortic wall integrity and is a surgical emergency requiring immediate repair. The mortality rate approaches 90 percent if rupture occurs outside the hospital. Although open surgical repair has been performed safely, an endovascular approach is used in select patients if the aortic and iliac anatomy are amenable. Two large randomized controlled trials did not find any improvement in mortality rate or morbidity with this approach compared with conventional open surgical repair.