When Should an Abdominal Aortic Aneurysm Be Treated?

Timing of repair. Early repair of small AAAs (4 cm to 5.5 cm) has no long-term survival benefit compared to ultrasound surveillance without repair.^16,17 Therefore, AAAs <5.5 cm should be followed with regular ultrasound surveillance every six months, with referral to surgery if the diameter reaches 5.5 cm, or grows >1 cm a year. The size at which surgery should be performed might be lower in women, given that their risk of rupture is higher than men. A thoughtful discussion of individual risks should take place in every case, but in many patients, even the elderly, repair of a large asymptomatic AAA is indicated. ⁵

Back to the Case

Our patient should have repeat imaging of his AAA in six months and regular surveillance afterward to monitor for growth every six months. When the AAA is >5.5 cm or if it grows >1 cm a year, he should be evaluated for EVAR or open repair.

Bottom Line

The current USPSTF guidelines recommend one-time ultrasound-guided (USG) screening for AAA in men aged 65 to 75 with a history of smoking. If an AAA >3 cm is found, the patient should undergo regular USG screening every six months. The AAA should be repaired if >5.5 cm or symptomatic, via either an endoscopic or open approach.

Dr. Best is a hospitalist at University of Washington Medicine at Harborview and associate program director of the internal-medicine residency program at the University of Washington, Seattle. Dr. Carpenter is a fellow in the division of geriatrics at the University of California at San Franscisco.

References

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