What is the most appropriate indication for preoperative angiography in elective abdominal aortic aneurysm (AAA) surgery?

History of Claudication is the Primary Indication for Preoperative Angiography in Elective AAA Surgery

The most appropriate indication for preoperative angiography in elective abdominal aortic aneurysm surgery is a history of claudication (option d). 1, 2

Rationale for Preoperative Imaging in AAA

• Current guidelines strongly recommend CT angiography (CTA) or MR angiography (MRA) as the primary preoperative imaging modalities for AAA evaluation, with catheter arteriography having very limited utility 1
• Catheter arteriography is now primarily reserved for specific clinical scenarios where other imaging modalities are contraindicated or additional information is needed 1

When Preoperative Angiography May Be Indicated

• History of claudication is the strongest indication for preoperative angiography, as it suggests concurrent peripheral arterial disease that may affect surgical planning and outcomes 2, 3
• Research has shown that patients with claudication have the highest number of arteriographic abnormalities that could modify surgical approach 2
• Angiography in these patients helps identify:
  • Extent of peripheral arterial disease
  • Need for concomitant revascularization procedures
  • Optimal sites for clamping and anastomosis 2, 4

Why Other Options Are Not Primary Indications

• Suspected contained rupture (option a) requires emergency intervention rather than elective preoperative angiography, which would delay necessary treatment 1
• Suspected inflammatory aneurysm (option b) is better evaluated with CTA or MRA, which provide detailed information about wall thickness and surrounding inflammation 1
• Aneurysm larger than 7 cm (option c) alone is not an indication for angiography; size is better assessed by CTA or ultrasound, and large size itself doesn't necessitate angiographic evaluation 1, 5

Current Approach to Preoperative Imaging for AAA

• For pre-intervention studies in elective AAA repair, multidetector CT (MDCT) or CTA is now the optimal choice 1
• MRA may be substituted if CT cannot be performed (e.g., due to contrast allergy) 1
• Catheter arteriography has very limited utility, primarily indicated when:
  • Patient has significant contraindications to both CTA and MRA 1
  • Patient has symptoms of peripheral arterial disease like claudication 2, 3
  • There is need to evaluate specific vascular anatomy that might affect surgical approach 2, 4

Clinical Implications

• Selective rather than routine use of angiography is now recommended based on specific indications 2, 6
• When multiple indications are present (especially four or more), the likelihood of angiography altering surgical management increases significantly 2
• The presence of claudication has been shown to yield the most actionable information from angiography compared to other indications 2, 3

Pitfalls to Avoid

• Relying on angiography alone for AAA size assessment is inappropriate; CTA or ultrasound provides more accurate diameter measurements 1
• Delaying intervention for angiography in symptomatic or ruptured AAA can increase mortality 1
• Routine angiography for all AAA patients is no longer supported by evidence and exposes patients to unnecessary risks and costs 2, 6