What is the recommended screening frequency for abdominal aortic aneurysm (AAA) in patients with a size less than 4.0 cm?

The recommended screening frequency for abdominal aortic aneurysm (AAA) in patients with an aneurysm size of less than 4.0 cm is typically once a year. This guideline is based on clinical studies that indicate lower risks of rupture and complications in smaller aneurysms. Regular monitoring through yearly ultrasound examinations allows healthcare providers to assess any changes in the size of the aneurysm and intervene if it begins to grow or poses a higher risk.

In patients with an AAA measuring 4.0 cm or larger, the annual screening becomes crucial because these aneurysms carry a significantly increased risk of rupture. However, since those under 4.0 cm have a much lower risk of clinical complications, annual surveillance is considered adequate to track any potential progression in size. This approach balances the need for monitoring with the understanding that a smaller aneurysm is less likely to lead to immediate health issues.