Abdominal Aortic Aneurysm

Overview, Causes, & Risk Factors

Abdominal aortic aneurysm (AAA) is the term for enlargement and weakening of aportion of the abdominal aorta.

What is going on in the body?

The abdominal aorta is the main blood vessel that supplies blood to internalorgans in the lower part of the body. Under certain conditions, a section ofthe aorta may weaken and swell. If the aneurysm should burst, large amounts ofblood can be lost. This can quickly cause death. Blood can also leak in betweenthe layers of the aorta and block arteries leading from it. This can causeserious 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 fattymaterial builds up inside the aorta. This buildup causes inflammation andweakens the affected blood vessel.

Other causes of abdominal aortic aneurysms include:

  • injury, such as a crushinjury 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 pressureincreases the risk of AAA. More than half of those diagnosed with AAA have highblood pressure. Cigarettesmoking also increases the risk of AAA and can make AAA worse. Chroniccoughing, such as the coughfrom chronic obstructive pulmonarydiseases such as emphysema, can make the aneurysm worse.

    AAA is more common among Caucasian people. It affects men 4 times more oftenthan 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 sometimesAAA is very painful. The pain is often felt in the lower back or the abdomen. Itis usually a steady pain that does not go away, although it may be relieved bychanging position. Sometimes the person can sense an abnormal pulse in theabdomen. Circulation tothe 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 ofthe internal bleeding, the person may go into shock, and death may rapidlyfollow.

    Diagnosis & Tests

    How is the condition diagnosed?

    A physical examination will often reveal an enlarged abdominal aorta. Thehealthcare provider can sometimes hear abnormal sounds over the enlarged aorta.An ultrasound test is commonly used to confirm the diagnosis of AAA. Otherimaging studies, such as an abdominal CT scan or abdominal MRI, may be done toprovide 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 bloodpressure
  • avoiding or treating high cholesterol
  • quitting smoking
  • 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 thathave 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 survivelong enough to have surgery, which is the only treatment for the condition. Ofthose individuals, only half survive and recover from the surgery. Earlydetection of the aneurysm, before it ruptures, is key to successful treatmentof the problem.

    If the aneurysm has not ruptured, surgery is recommended in the followingsituations:

  • 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 isthen 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 relativelyhealthy, the outcome is very good. But emergency surgery for a ruptured AAA hasabout a 50% chance of death. Other side effects include bleeding, infection,and allergic reaction to theanesthesia.

    What happens after treatment for the condition?

    After recovery from surgery, the person can slowly return to regularactivities. It’s important to make appropriate lifestyle changes to lower therisk of further circulatory system problems. These changes include eating ahealthy diet to minimize heartdisease, avoiding smoking, exercising in moderation, andmaintaining a healthy weight.

    How is the condition monitored?

    Before surgery, the size of an aneurysm can be evaluated using an ultrasoundtest. After recovery from surgery, the person should have no further symptoms.Any new or worsening symptoms should be reported to the healthcare provider.

    Article type: xmedgeneral