Treatment Options for Abdominal Aortic Aneurysm

Surveillance of Abdominal Aortic Aneurysm

There have been two major randomized clinical trials (ADAM and USAT) regarding the treatment of small abdominal aortic aneurysms (AAA) that concluded that for aneurysms between 4.0 and 5.5 cm. in size, surveillance every 3-6 months was safe and that early surgery did not result in increased long term survival. The studies divided people diagnosed with an abdominal aortic aneurysm into two groups - one group opted for early intervention and surgical repair, while the other group chose to undergo non-invasive surveillance with ultrasound every 3-6 months. In both studies, more than 60% of the patients who were monitored underwent surgical repair within 4 years and the mortality rate of both groups (surveillance and early surgical repair) was equivalent. These studies concluded that:

• Small AAAs (less than 5 cm. diameter for average person) have a low risk of rupture.
• Early surgical repair (when diameters are 4.5 cm. to 5.5 cm.) confers no advantage in terms of survival when the two groups are compared.
• The majority of small AAAs eventually expand to the point of requiring elective surgery to prevent rupture at a later time.

Small abdominal aortic aneurysms are followed with regular surveillance of ultrasound imaging at six month intervals (average). Estimates are that within 2 to 2.5 years most will probably reach 5.5 cm. in diameter at which time surgical intervention would be appropriate.

It is crucial that if an individual with an abdominal aortic aneurysm smokes, they quickly seek help to stop smoking since smoking is closely associated with expansion of aneurysms. In addition, in the presence of elevated blood pressure,physicians may prescribe medication (e.g., beta blockers) to lower blood pressure thereby relieving stress on the walls of the aorta.