Abdominal aortic aneurysm (AAA or triple A) is a localized enlargement of the abdominal aorta such that the diameter is greater than 3 cm or more than 50% larger than normal. They usually cause no symptoms, except during rupture. Occasionally, abdominal, back, or leg pain may occur. Large aneurysms can sometimes be felt by pushing on the abdomen. Rupture may result in pain in the abdomen or back, low blood pressure, or loss of consciousness, and often results in death. AAAs occur most commonly in those over 50 years old, in men, and among those with a family history.Additional risk factors include smoking, high blood pressure, and other heart or blood vessel diseases. Genetic conditions with an increased risk include Marfan syndrome and Ehlers-Danlos syndrome. AAAs are the most common form of aortic aneurysm. About 85% occur below the kidneys with the rest either at the level of or above the kidneys. In the United States, screening with abdominal ultrasound is recommended for males between 65 and 75 years of age with a history of smoking. In the United Kingdom and Sweden, screening all men over 65 is recommended. Once an aneurysm is found, further ultrasounds are typically done on a regular basis.