Abdominal Aortic Aneurysm Management

Clinical Presentation

Most abdominal aortic aneurysms (AAAs) remain asymptomatic until rupture, and are typically discovered incidentally on imaging performed for unrelated reasons 1
The majority of AAAs produce no symptoms and are detected as incidental findings on ultrasound, CT, or other abdominal imaging studies, with approximately two-thirds being asymptomatic 2
Patients with symptomatic AAAs may present with acute abdominal pain, back pain, or flank pain, which indicates impending rupture and necessitates immediate emergency department evaluation 3
The classic presentation of a symptomatic AAA includes acute back pain with a pulsatile abdominal mass, often associated with retroperitoneal hemorrhage 4
Pain may be described as "sharp" or "stabbing" rather than the classic "tearing" or "ripping" quality, and hypovolemic shock may occur with frank rupture 2, 5, 6

Duplex ultrasound is the standard imaging technique for AAA screening and surveillance, measuring the leading-edge to leading-edge anteroposterior diameter, with 95% accuracy for measuring aneurysm diameter 2, 5, 7
CT without contrast is diagnostically equivalent to ultrasound for AAA detection when ultrasound is not suitable 7
CT angiography (CTA) is the optimal imaging modality for surgical planning when AAAs reach 5.5 cm or become symptomatic, due to its wide availability, accuracy, speed, and anatomic detail 5, 6, 7

The European Society of Cardiology provides specific surveillance intervals based on aneurysm size and sex, with recommendations for men and women to undergo repeat imaging at varying intervals depending on aneurysm diameter 2
Surgery is generally recommended when the AAA diameter reaches 5.5 cm in men and 5.0 cm in women, due to the higher rupture risk in women 1, 8
Saccular morphology at smaller diameters warrants closer surveillance or earlier intervention, as 25% of acute presentations occur at <5.5 cm 3
The American College of Radiology recommends duplex ultrasound as the standard imaging technique for AAA screening and surveillance, with CT angiography as the optimal imaging modality for surgical planning 7
The European Heart Journal recommends surveillance intervals based on aneurysm size and sex, with recommendations for men and women to undergo repeat imaging at varying intervals depending on aneurysm diameter 2