What is an abdominal aortic aneurysm (AAA)?

An artery is a blood vessel that carries oxygen-rich blood from your heart to the rest of your body. An aneurysm is a weakened section of an artery—it bulges out like a balloon under the pressure of the blood flowing through it.

The aorta is your largest artery. It leaves your heart and travels through your chest and then down through your abdomen (belly) before splitting into smaller arteries that go to your legs. When an aneurysm happens in the section of the aorta that travels through your abdomen, it's called an abdominal aortic aneurysm, or AAA.

The abdominal aorta is the main blood vessel that carries blood from the heart to the lower body. In part, the abdominal aorta feeds into the renal arteries, which supply blood to the kidneys.

An abdominal aortic aneurysm (AAA) is a potentially serious medical condition that occurs when a section of the abdominal aorta begins to bulge. If an aneurysm is small it may not require treatment but only monitoring with ultrasound tests, which use sound waves to create images of the blood vessel and show the extent of the aneurysm. However, a large abdominal aortic aneurysm can rupture and is a medically serious event requiring emergency medical care. The survival rate for patients who experience a ruptured abdominal aortic aneurysm is less than 40 percent.

Dr. Frank R. Arko, MD
Vascular Surgeon

An abdominal aortic aneurysm is a bulging of the main blood vessel off of the heart. It can occur anywhere along the length of the aorta but is most common just below the arteries that go to the kidneys. This can be felt if big enough just above the belly button. It generally occurs over the age of 65 and can be evaluated with either physical exam or with ultrasound evaluation. There are certain risk factors that increase the risk. This includes any history of smoking, hypertension, high cholesterol, and in those who have had a heart bypass or coronary stents. Treatment is performed with either a stent graft or open surgery. Intervention is typically recommended in those whose aneurysms are 5 cm in size. Without treatment the risk is rupture of the aneurysm that can be fatal.

The aorta is a large blood vessel that carries blood from the heart to all parts of the body. Most aortic aneurysms develop over time in the lower abdominal aorta, below the renal arteries, which supply blood to the kidneys.

Abdominal aortic aneurysms result from a weakening of the blood vessel wall which then dilates or buldges out. If the aneurysm is small it just needs to be followed with ultrasounds. Larger aneurysms can be treated either with open surgery or minimally invasive techniques using stent grafts. Aneurysms can rupture and unfortunately when this happens most of these people do not survive.

Dr. Joshua I. Greenberg, MD
Vascular Surgeon

An abdominal aortic aneurysm (AAA) is essentially a dilation of the aorta, which is the biggest blood vessel in the body. It's a condition that many people don't know they have. It's very treatable, but if not treated, it can be lethal.

An abdominal aortic aneurysm, also called AAA or triple A, is a bulging, weakened area in the wall of the aorta (the largest artery in the body) resulting in an abnormal widening or ballooning greater than 50 percent of the normal diameter (width).

The aorta extends upward from the top of the left ventricle of the heart in the chest area (ascending thoracic aorta), then curves like a candy cane (aortic arch) downward through the chest area (descending thoracic aorta) into the abdomen (abdominal aorta). The aorta delivers oxygenated blood pumped from the heart to the rest of the body.

The most common location of arterial aneurysm formation is the abdominal aorta, specifically, the segment of the abdominal aorta below the kidneys. An abdominal aneurysm located below the kidneys is called an infrarenal aneurysm. An aneurysm can be characterized by its location, shape, and cause.

An abdominal aortic aneurysm is a fairly common condition in which the aorta dilates (forms a bulge) causing the aortic wall in that area to become thin and weak. The main risk is that that portion of the aorta could rupture. Once an aneurysm ruptures, it can be deadly.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.