Stent-Graft Limb Deployment in the External Iliac Artery Increases the Risk of Limb Occlusion Following Endovascular AAA Repair

Abstract

To assess whether deployment of an endograft limb in the external iliac artery (EIA) increases the rate of limb occlusion following endovascular aneurysm repair (EVAR). Interrogation of a prospectively maintained database identified 661 patients (596 men; median age 73 years, range 37-93) with infrarenal abdominal aortic aneurysm who underwent EVAR between 1996 and 2010 using Zenith stent-grafts predominately. Of these, 567 patients [56 (9.9%) women] had both endograft limbs deployed in the CIA (1203 limbs at risk), while 94 patients [9 (9.6%) women] had at least 1 limb in the EIA (22 bilateral; 116 limbs at risk). An adjunctive bare metal stent was used in 8 (9%) limbs deployed in the EIA. There were 31 limb occlusions, all unilateral: 17 (3%) patients in the CIA group had an occluded limb (1% of limbs at risk) vs. 14 (15%) patients in the EIA group (12% of limbs at risk; p<0.0001). The median time to occlusion was 3 months (0-60) in the CIA group and 1 month (0-36) in the EIA group. The majority of occlusions were treated by extra-anatomical revascularization, most often a femorofemoral crossover bypass. No legs were amputated following occlusion of a limb placed in the CIA, but there were 3 amputations in the EIA group (p=0.003). Deployment of endograft limbs into the EIA led to a higher rate of occlusion and leg amputation. Increased tortuosity of the EIA and a smaller caliber vessel are likely to account for the increased risk.