Distal internal iliac artery embolization: a procedure to avoid.

OBJECTIVES: Internal iliac artery (IIA) coil embolization as an adjunct to endovascular stent grafting (ESG) is common practice for treating abdominal aortic aneurysm (AAA) in patients with a substantially enlarged common iliac artery requiring extension of the stent-graft limb into the external iliac artery. The literature describing pelvic ischemia in association with IIA coil embolization contains conflicting reports of symptom severity. We studied IIA occlusion outcome as a function of coil placement in the IIA. METHODS: From August 1997 to March 2002, 20 patients with AAA underwent ESG with unilateral IIA coil embolization. Coils were placed proximal to the first branch of the IIA in 8 patients and distal to the first branch in 12 patients. Symptoms of pelvic ischemia and mid-term outcome were studied. RESULTS: Patients included 18 men and 2 women with mean age of 70(1/2) years (range, 53-86 years). Mean diameter of AAA was 54.4 mm (range, 38-80 mm), and of common iliac artery was 24.2 mm (range, 15-48 mm). Ten patients (50%) had new onset of symptoms of pelvic ischemia after endograft procedures: 1 of 8 patients (13%) with proximal IIA embolization had buttock claudication, and 9 of 12 patients (75%) with distal IIA embolization had pelvic ischemic symptoms, including buttock claudication in 8 and impotence in 1 (P =.02, Fisher exact test). No colonic ischemia occurred in this series. At 12-month follow-up, 4 patients with distal IIA embolization were symptom-free. At further follow-up to 24 months, 4 patients remained significantly limited with symptoms of claudication. CONCLUSIONS: A significantly higher incidence of symptoms of pelvic ischemia occurred with more distal placement of coils for IIA embolization. Failure to control for extent of coil placement may account for the apparently conflicting results in published studies. IIA coil embolization should be performed as proximal as possible to prevent interference with pelvic collateral circulation.

Internal iliac artery occlusion using a stent-graft tunnel during endovascular aneurysm repair: a new alternative to coil embolization.

PURPOSE: To report a new endovascular technique for internal iliac artery (IIA) occlusion during stent-graft treatment in patients with aortoiliac aneurysm. TECHNIQUE: Stent-grafts measuring 20 to 28 mm in diameter and 37.5 mm long were deployed at the iliac bifurcation to occlude the IIA at its origin. Subsequent deployment of an aortic bifurcation endograft with ipsilateral extension into the external iliac artery was through this iliac stent-graft tunnel. This approach has been used in 5 patients with abdominal aortic aneurysm and common iliac artery aneurysm (n=4) or isolated iliac artery aneurysm. Proximal IIA occlusion was achieved in all cases with no distal type I endoleak. IIA patency on the side opposite to the tunnel procedure was preserved in each case. No patient described new onset of pelvic ischemic symptoms. Over a mean 10-month follow-up (range 1-12), there was no secondary procedure required for type I endoleak. Three patients had a CIA aneurysm diameter change of -1, -4, and 0 mm at 1 year. CONCLUSIONS: This new method for IIA occlusion at its origin without coil embolization may prove to be a useful adjunct to endovascular aortoiliac aneurysm repair. The technique is simple, rapid, and may minimize the risk of pelvic ischemia.

Bell-bottom aortoiliac endografts: an alternative that preserves pelvic blood flow.

OBJECTIVE: Dilated common iliac arteries that complicate aortic aneurysm stent grafting usually have been managed with endograft extension across the iliac artery bifurcation with internal iliac artery (IIA) occlusion. We studied 25 patients with significant common iliac artery (CIA) dilation treated with two methods: endograft extension across the iliac bifurcation or a new approach with a flared cuff within the CIA that preserves the IIA. METHODS: Of 86 patients with abdominal aortic aneurysm (AAA) who underwent bifurcated endovascular stent grafting (ESG), 25 (29.1%) had at least one dilated CIA. Two treatment groups had different methods of management of iliac artery dilation. Group 1 underwent ESG with straight extension across the iliac bifurcation and IIA coil embolization before the ESG procedure (n = 2) or simultaneously with ESG (n = 8). Group 2 underwent ESG with flared distal cuff (AneuRx, Medtronic AVE, Santa Rosa, Calif) contained within the CIA, the so-called "bell-bottom" procedure, thus preserving the IIA (n = 15). Iliac artery dimensions, operating room time, fluoroscopy time, and postoperative complications were prospectively gathered. RESULTS: Two women and 23 men had mean diameters of AAA of 56.6 mm (range, 38 to 98 mm) and of CIA of 21.4 mm (range, 15 to 48 mm). The diameters of CIA treated with device extension into external iliac artery after IIA coil embolization in group 1 and with the bell-bottom procedure in group 2 were not different (mean CIA diameter, 19.9 mm; range, 15 to 26 mm; and mean, 19.1 mm; range, 15 to 24 mm; respectively). However, significantly lower operating room and catheter procedure times were found in group 2 compared with group 1 (137 versus 192 minutes; 58 versus 106 minutes; P =.02 and.02, respectively). No periprocedural type I endoleaks were found in either group. Nine patients in group 2 also had a second contralateral CIA aneurysm, and five patients (mean CIA diameter, 33.0 mm; range, 22 to 48 mm) underwent treatment with extension across the iliac artery bifurcation and IIA occlusion. Use of the bell-bottom procedure on the other side allowed preservation of one IIA. Four cases (mean diameter, 19.3 mm) also underwent contralateral bell-bottom procedure. Two of these group 2 patients had complications, with severe buttock claudication in one and distal embolism necessitating limb salvage bypass after preoperative coil embolization of the IIA in another. CONCLUSION: Significant CIA ectasia or small aneurysm is often associated with AAA. In such cases, the bell-bottom procedure that preserves IIA circulation is a new alternative to the common practice of placement of endograft extensions across the iliac artery bifurcation in patients with at least one CIA diameter of less than 26 mm. Additional benefits include reduced total procedure time. Early technical success appears to justify continued use. However, long-term evaluation is necessary to determine durability because the risk of rupture as the result of potential expansion of the excluded iliac artery or late failure is unknown.