Abdominal Aortic Aneurysm

What is an Abdominal Aortic Aneurysm?

The abdominal aorta is the largest artery within the abdomen and carries oxygenated blood to the abdominal / pelvic organs and down to the legs. Widening of an artery to more than one and one half times its normal diameter ( >150 percent) is an aneurysm. Most abdominal aortic aneurysms (AAA) exist without symptoms.  An AAA is more common beyond 60 years of age and is five times more common in men.  Approximately 5 percent of men over age 60 have this type of aneurysm and 10% in men older than 70.  Atherosclerosis (hardening of the arteries) causes weakening of the arterial wall leading to aneurysmal formation.  Risk factors for an AAA include increased age, smoking, high blood pressure, family history, elevated cholesterol.  The most common location for this type of aneurysm is in the segment of the aorta found within the upper abdomen.

Should I worry about having one?

Occlusion or complete blockage of the aortic aneurysm causing sudden loss of blood flow to the pelvis and legs is possible as is dislodgement of plaque or clot from within the aneurysm which will be flushed downstream.  The most feared complication of rupture is also the most common.  The larger the aneurysm becomes the more likely it is to rupture.  A 5 cm AAA has a 16% risk of rupture in 5 years time.  At 6 cm diameter, non-operative treatment is prohibitive.

The large majority of people (90%) having rupture of an abdominal aortic aneurysm (AAA) will die before ever getting to a hospital.  Of those that do get to the hospital, only 45% overall will survive. Within this latter group, those patients presenting to the Emergency Department in shock (low blood pressure, pale, fast heart rate, etc.), only 10% will survive.  Genetic predominance is greatest in the sons of women having an AAA.  Also, the rupture risk is greater in women.

The complication rate for repair of an AAA is significantly higher when emergent repair is required.

How do I find out if I have an AAA?

Generally speaking, most abdominal aortic aneurysms can be seen easily by either ultrasound imaging and/or a CT scan.  Ultrasound imaging success is more difficult in the obese. Men over 59 years of age should be screened for an AAA.  If you have or have had a relative with an AAA, screening should start between 40-45 years of age.   

If you have an AAA, contact your Primary Care Physician or your Surgeon for further evaluation.

Treatment Options

Traditional open abdominal surgery that secures an artificial graft in place of the AAA is the “gold standard” procedure.  Dr. Rudolph Matas first performed this operation in Louisiana in 1951.  This technique is still used today.  Overall, this surgical procedure has the best long-term results (10 years or more) in people younger than 70 years old.  A mortality rate of  3- 5% is typical for elective repairs and patients are typically in the hospital for a week.

Endovascular repair (EVR) has available for several years and is most often chosen for higher risk patients (severe lung and/or heart disease) and those 70 years or older.  EVR has very good short-term results (under 10 years).  This procedure utilizes catheter-assisted placement of a stented graft in combination with both a surgeon and an interventional radiologist.  This stented graft is opened from within the channel that blood flows to exclude the AAA.  EVR has a lower complication profile and shorter hospital stay (usually less than 2 days) but with higher total costs.  Follow-up imaging over several years is required.

Conservatism might be chosen by your physician is situations of a small AAA, horrendous heart disese, short life expectancy, or in a patient with cancer.

When should I consider AAA repair?

After discussing options with a surgeon by the time the AAA is at least 4.5 cm.
New symptoms of back or hip pain in a patient aware that they have an AAA.
Consistent enlargement in size over consecutive 6-12 month intervals.
Family member having had a ruptured AAA.

If you have questions or desire a screening test, please contact us via e-mail or call our office.