At what size should an AAA prompt a referral to a vascular surgeon?

An abdominal aortic aneurysm (AAA) is considered significant when it measures 4.5 cm or larger, at which point referral to a vascular surgeon is typically warranted. This is due to the increased risk of complications, including rupture, which escalates with the size of the aneurysm. Guidelines suggest monitoring smaller aneurysms but highlight the threshold of 4.5 cm for intervention, as studies have shown that aneurysms of this size carry a greater risk of rupture, necessitating surgical evaluation and potential repair.

Smaller aneurysms can often be managed conservatively with regular imaging and monitoring; thus, the threshold size is an important clinical decision point. Referring at 4.5 cm allows for timely intervention and management to prevent life-threatening complications.