What is the recommended treatment for a 5cm iliac artery aneurysm?

Treatment of 5cm Iliac Artery Aneurysm

Elective repair is strongly recommended for a 5cm iliac artery aneurysm due to the significant risk of rupture at this size. 1

Indications for Repair

• Iliac artery aneurysms ≥3.5cm should undergo elective repair, with a 5cm aneurysm well above this threshold 1
• The risk of rupture increases significantly with size, with ruptured iliac aneurysms having a median diameter of 6.8cm at presentation 1
• Symptomatic iliac aneurysms warrant immediate repair regardless of size 1
• Rupture of iliac aneurysms at diameters <4cm is rare, but rupture risk increases substantially above this size 1, 2

Treatment Options

Open Surgical Repair

• Open repair is indicated for patients who are good or average surgical candidates 1
• Open repair should be considered for patients who cannot comply with the long-term surveillance required after endovascular repair 1
• Perioperative mortality is higher with open repair compared to endovascular approaches, particularly for ruptured aneurysms 3

Endovascular Repair

• Endovascular repair is a reasonable alternative, especially for patients at high risk for open surgery due to comorbidities 1
• Benefits include shorter hospital stays (1.3 days vs 5.2 days for open repair) and lower transfusion requirements 3
• Requires long-term surveillance imaging to monitor for endoleaks and aneurysm sac stability 1

Technical Considerations

• When treating iliac aneurysms, preservation of at least one hypogastric (internal iliac) artery is recommended to decrease the risk of pelvic ischemia 1
• Exclusion of internal iliac arteries can lead to significant complications:
  • Buttock claudication (27% with unilateral exclusion, 36% with bilateral exclusion) 1
  • Erectile dysfunction (10% of men) 1
  • Bowel ischemia (rare, <1%) 1

Post-Procedure Management

• Periodic long-term surveillance imaging is mandatory after endovascular repair to:
  • Monitor for endoleaks 1
  • Document shrinkage or stability of the excluded aneurysm sac 1
  • Determine the need for further intervention 1
• CT imaging is recommended at 1 month and 12 months post-procedure, and annually thereafter if stable 1

Pitfalls and Caveats

• Patients with iliac aneurysms should be evaluated for concomitant abdominal aortic aneurysms (AAA), as they frequently coexist 1, 4
• Patients who undergo repair of isolated iliac aneurysms without aortic replacement should be monitored for development of AAA (29% in one study) 4
• Smoking cessation is strongly advised for all patients with aneurysms to reduce the risk of expansion 1
• Beta-blockers may be considered to reduce the rate of aneurysm expansion 1