Overview, Causes, & Risk Factors
Abdominal aortic aneurysm (AAA) is the term for enlargement and weakening of a
portion of the abdominal aorta.
What is going on in the body?
The abdominal aorta is the main blood vessel that supplies blood to internal
organs in the lower part of the body. Under certain conditions, a section of
the aorta may weaken and swell. If the aneurysm should burst, large amounts of
blood can be lost. This can quickly cause death. Blood can also leak in between
the layers of the aorta and block arteries leading from it. This can cause
serious damage to the organs supplied by those arteries.
What are the causes and risks of the condition?
The most common cause of AAA is atherosclerosis. In this condition, a fatty
material builds up inside the aorta. This buildup causes inflammation and
weakens the affected blood vessel.
Other causes of abdominal aortic aneurysms include:
injury, such as a crush
injury from a motor vehicle accident
inherited conditions that cause weakened or abnormal blood vessel walls
infection carried in the bloodstream from other parts of the body
High blood pressure
increases the risk of AAA. More than half of those diagnosed with AAA have high
blood pressure. Cigarette
smoking also increases the risk of AAA and can make AAA worse. Chronic
coughing, such as the cough
from chronic obstructive pulmonary
diseases such as
emphysema, can make the aneurysm worse.
AAA is more common among Caucasian people. It affects men 4 times more often
than women. It occurs most often in people between ages 60 and 90.
Symptoms & Signs
What are the signs and symptoms of the condition?
Many people with an abdominal aortic aneurysm have no symptoms. But sometimes
AAA is very painful. The pain is often felt in the lower back or the abdomen. It
is usually a steady pain that does not go away, although it may be relieved by
changing position. Sometimes the person can sense an abnormal pulse in the
abdomen. Circulation to
the lower extremities can be affected.
Rupture of an abdominal aortic aneurysm is usually associated with sudden,
excruciating pain in the lower abdomen and back. Depending on the severity of
the internal bleeding, the person may go into shock, and death may rapidly
Diagnosis & Tests
How is the condition diagnosed?
A physical examination will often reveal an enlarged abdominal aorta. The
healthcare provider can sometimes hear abnormal sounds over the enlarged aorta.
An ultrasound test is commonly used to confirm the diagnosis of AAA. Other
imaging studies, such as an abdominal CT scan or abdominal MRI, may be done to
provide more information about the aneurysm.
Prevention & Expectations
What can be done to prevent the condition?
People can lower their risk of abdominal aortic aneurysm by:
controlling high blood
avoiding or treating high cholesterol
obtaining effective treatment for
chronic obstructive pulmonary disease
What are the long-term effects of the condition?
A ruptured abdominal aortic aneurysm can cause death. Small aneurysms that
have not ruptured are monitored closely to prevent rupture.
What are the risks to others?
Abdominal aortic aneurysms are not contagious and pose no risk to others.
Treatment & Monitoring
What are the treatments for the condition?
Only 40% to 50% of the people with a ruptured abdominal aortic aneurysm survive
long enough to have surgery, which is the only treatment for the condition. Of
those individuals, only half survive and recover from the surgery. Early
detection of the aneurysm, before it ruptures, is key to successful treatment
of the problem.
If the aneurysm has not ruptured, surgery is recommended in the following
when the person has severe symptoms
when the aneurysm is bigger than 5 cm across
when it has grown by at least 1 cm over 6 to 12 months
In surgery, the weakened part of the aorta is removed. An artificial graft is
then used to replace the portion removed.
What are the side effects of the treatments?
If surgery has been performed before rupture, and the patient is relatively
healthy, the outcome is very good. But emergency surgery for a ruptured AAA has
about a 50% chance of death. Other side effects include bleeding, infection,
and allergic reaction to the
What happens after treatment for the condition?
After recovery from surgery, the person can slowly return to regular
activities. It's important to make appropriate lifestyle changes to lower the
risk of further circulatory system problems. These changes include eating a
healthy diet to minimize heart
disease, avoiding smoking, exercising in moderation, and
maintaining a healthy weight.
How is the condition monitored?
Before surgery, the size of an aneurysm can be evaluated using an ultrasound
test. After recovery from surgery, the person should have no further symptoms.
Any new or worsening symptoms should be reported to the healthcare provider.