What is an abdominal aortic aneurysm?
An abdominal aortic aneurysm is an enlargement of the lower part of the aorta that extends through the abdominal area (at times, the upper portion of the aorta in the chest can be enlarged). The aorta is the main blood vessel that carries blood from the heart to the rest of the body. Like most arteries, the aorta is elastic, which allows it to be filled with blood under high pressure. An aneurysm develops when the wall of the artery becomes weakened and distended like a balloon. The analogy of a bubble in a garden hose would be appropriate in describing an aneurysm. Aneurysms usually are discovered before they produce symptoms, such as back pain, but like the weakened hose, they may rupture if they become too large. Since a ruptured aneurysm is extremely dangerous and can cause life-threatening bleeding, aneurysms are best corrected by an operation before this happens.
Aneurysm of the abdominal aorta
What are some predisposing factors for abdominal aneurysms?
- Congenital defects, such as an inherited weakness in the blood vessel wall; example, Marfan's syndrome
- High blood pressure (hypertension). This speeds up damage to blood vessel walls.
- Arteriosclerosis (also called atherosclerosis). This occurs when the normal lining of the arteries deteriorates, the walls of the arteries thicken, and deposits of fat and plaque block the flow of blood through the arteries. The association of arteriosclerosis with the development of aneurysms is controversial.
- High cholesterol
Who should be screened for abdominal aortic aneurysm?
An abdominal aortic aneurysm (AAA) is a major health risk that may not have related symptoms until a life-threatening event occurs, such as aneurysm rupture. An abdominal ultrasound is a preventive screening tool that can be used to identify an AAA so that prompt treatment can be provided prior to aneurysm rupture.
Medicare screening guidelines
Currently, Medicare is offering a one-time, free abdominal ultrasound AAA screening to qualified senior citizens as part of its Welcome to Medicare physical. This physical must be conducted within the first 12 months of enrollment in Medicare. Men who have smoked at least 100 cigarettes during their lifetime, and men and women with a family history of AAA qualify for the Medicare screening.
This screening recommendation is based on the U.S. Preventive Services Task Force (USPSTF) Screening for Abdominal Aortic Aneurysm: Recommendation Statement. AHRQ Publication No. 05-0569-A, February 2005. Agency for Healthcare Research and Quality, Rockville, Md.
Additional screening guidelines
The Society for Vascular Surgery (SVS) and the Society for Vascular Medicine and Biology (SVMB) recommend abdominal ultrasound AAA screening for these patients:
- All men ages 60 to 85 years
- All women ages 60 to 85 years with cardiovascular risk factors
- All men and women ages 50 and older with a family history of AAA
Cleveland Clinic supports the SVS and SVMB screening recommendations for these patients who have a higher risk of developing an AAA. Coverage for abdominal AAA ultrasound screening may differ, depending on your insurance. Therefore, please contact your insurance provider for specific coverage options before scheduling this test.
What are some different types of aneurysms?
- Abdominal aneurysm — in an artery in the abdomen (mid-section)
- Thoracic aneurysm — in an artery in the chest area
- Cerebral aneurysm — in an artery in the brain (usually treated by neurosurgeons)
- Peripheral aneurysm — in the large arteries that run down the legs and behind the knees, and occasionally arms
Most aneurysms occur in the abdomen. Abdominal aortic aneurysms occur most frequently in people over age 60 and most commonly at a point in the aorta just below the level of the kidneys. Men are more commonly affected by aneurysms than women.
What are the symptoms of abdominal aneurysms?
Most people are unaware that they have an aneurysm because in most cases, there are no symptoms. However, as aneurysms grow, symptoms may include:
- Pulsating enlargement or tender mass felt by a physician when performing a physical examination
- Pain in the back, abdomen, or groin that may be prolonged and not relieved with position change or pain medication
A ruptured aneurysm usually produces sudden, severe pain and other symptoms such as loss of consciousness or shock, depending on the location of the aneurysm and the amount of bleeding. A ruptured aneurysm requires emergency treatment.
How is an abdominal aneurysm detected?
Most abdominal aneurysms are diagnosed during a routine physical examination or on X-ray when being tested for other health concerns.
Once an aneurysm is suspected, the following imaging tests may be used to determine size, location of the aneurysm, and treatment options:
Woven graft in place
- Ultrasound: high-frequency sound waves, inaudible to the human ear, are transmitted through body tissues. The echoes from the sound waves are recorded and transformed into video or photographic images.
- CT scans: computed tomography, commonly known as a CT scan, uses X-rays and computers to produce images of a cross-section of the body.
- Magnetic resonance imaging (MRI): a large magnet, radio waves, and a computer are used to produce clear pictures of the body. This procedure does not involve the use of X-rays.
- Angiogram: test in which a thin tube (catheter) is inserted into a blood vessel and a contrast dye is injected to make the blood vessels visible on the X-ray. This is rarely used to diagnose an abdominal aortic aneurysm but may be used to aid in the treatment of an aneurysm.
How are abdominal aneurysms treated?
Very large or symptomatic aneurysms require treatment. There are two types of surgical treatments for large aneurysms.
Open surgical repair
This involves the surgeon making an incision to access the abdominal aortic aneurysm. The diseased portion of the aorta is replaced with a graft that acts as a replacement blood vessel. Open surgical repair is a proven procedure that has a good track record and acceptable risks. But it also involves a long recovery period. Average hospital stay ranges from 5 to 8 days. The time until return to normal activity ranges from 6 weeks to 3 months. As with any operation, open surgical repair has a risk of complications. You will want to discuss them thoroughly with your doctor.
Stent graft in place
"Endovascular " means "inside or within a blood vessel"—and that is exactly how a small fabric tube that has metal stents attached to the fabric, called a stent-graft, is introduced into your body and moved into place. First, small incisions are made in each groin to get to arteries that carry blood from the aorta. The surgeon then moves the stent-graft up through these arteries until it is opened inside the diseased portion of aorta. The stent-graft reinforces the weakened part of the vessel from the inside and creates a new channel through which the blood flows, eliminating the risk of rupture. This procedure usually takes 1 to 3 hours and patients typically leave the hospital in 1 to 2 days. Return to normal activity ranges from 2 to 6 weeks. Like any medical procedure, endovascular repair has a risk of complications. It also involves regular routine follow-up visits with your doctor to evaluate the stent-graft. These regular follow-ups are extremely important and will require CT.
If you have a small aneurysm, your doctor will ask you to come back every 6 to 12 months for a CT or ultrasound to measure the size of your aneurysm and to review any other symptoms you may have. If surgery is recommended, you will need a comprehensive medical evaluation prior to your surgery. This may include a stress test and cardiology visit.
This information is provided by Cleveland Clinic and is not intended to replace
the medical advice of your doctor or health care provider.
Please consult your health care provider for advice about a specific medical condition.
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