Definition 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 off arteries leading from it. This can cause serious damage to the organs supplied by those arteries.
What are the signs and symptoms of the condition? Many people have no symptoms. But sometimes AAA is very painful. The pain is often felt in the lower back. It is a steady pain that does not go away. People can sense an abnormal pulse in their abdomen. A doctor can sometimes feel and hear an aneurysm.
What are the causes and risks of the condition? The most common cause of AAA is arteriosclerosis. In this condition a fatty material builds up inside the aorta. This build-up causes inflammation and weakens the affected blood vessel. High blood pressure and cigarette smoking can make AAA worse. Aneurysms may occur in people with inherited conditions that cause weakened or abnormal blood vessel walls. Injury and infection can also lead to AAA. The larger the aneurysm, the greater the risk of rupture. If AAA is left untreated, the risk of death is high. AAA's tend to be familial and mainly in males.
What can be done to prevent the condition? High blood pressure and high cholesterol should be treated. Other than that, nothing can be done to prevent this condition.
How is the condition diagnosed? A physical examination will often reveal an enlarged aorta. The doctor can sometimes hear abnormal sounds over the enlarged aorta. An ultrasound test is commonly used to confirm the diagnosis of AAA. Others examinations, such as CT scans and MRIs, are available but are more costly and not used as much, except to plan surgery.
What are the long-term effects of the condition? Careful monitoring is required. Small aneurysms, less then 5 cm, or about 2 inches wide, are usually just watched. Aneurysms greater than 5 cm wide are usually repaired surgically. Untreated large aneurysms can rupture and cause death quickly.
What are the risks to others? There are no risks to others.
What are the treatments for the condition? Blood pressure drugs can decrease the risk of AAA rupture. Surgery is needed to remove the aneurysm in 3 situations:
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 opened and an artificial graft is then used to replace that portion.
What are the side effects of the treatments? If surgery has been preformed 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.
What happens after treatment for the condition? Pulse, blood pressure, circulation, and heart status are carefully checked after surgery. People can slowly resume daily activity. The doctor should provide information and support to help the patient quit smoking and reduce stress.
How is the condition monitored? Before surgery, the size of an aneurysm can be evaluated using an ultrasound test. The person should tell the doctor if any symptoms return. This may mean they need further surgery.
Author: Eric Berlin, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
