Preserved Pelvic Circulation After Stent-Graft Treatment of Complex Aortoiliac Artery Aneurysms: A New Approach

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1 189 TECHNICAL NOTE Preserved Pelvic Circulation After Stent-Graft Treatment of Complex Aortoiliac Artery Aneurysms: A New Approach Martin Delle, MD, PhD 1 ; Lars Lönn, MD, PhD 2 ; Urban Wingren, MD, PhD 3 ; Lars Karlström, MD, PhD 3 ; Hans Klingenstierna, MD 5 ; Bo Risberg, MD, PhD 4 ; Peter Grahn, MD 5 ; and Ulf Nyman, MD, PhD 6 1 Department of Radiology, Södersjukhuset, Stockholm, Sweden. Departments of 2 Radiology, 3 Vascular Surgery, and 4 Surgery, Sahlgrenska University Hospital, Göteborg, Sweden. 5 Department of Radiology, Norra Älvsborgs Läns Hospital, Trollhättan, Sweden. 6 Department of Radiology, Trelleborg Hospital, Trelleborg, Sweden. Purpose: To describe an endovascular technique that allows stent-graft treatment of aortoiliac aneurysmal disease affecting both common iliac arteries (CIA), with maintenance of pelvic circulation on one side. Technique: For patients with aortoiliac aneurysms, both common femoral arteries (CFA) were surgically exposed. One internal iliac artery (IIA) was initially embolized with coils. A bifurcated stent-graft main body was deployed with the proximal end just below the renal arteries. On the ipsilateral side, the stent-graft limb was extended 3 cm beyond the orifice of the embolized IIA into the external iliac artery (EIA) using stent-graft limb extenders. On the contralateral side, the stent-graft limb was deployed so that the distal end was 10 to 15 mm proximal to the patent IIA orifice. Via a left brachial artery access, the IIA was catheterized, and stent-grafts were deployed from the distal end of the contralateral AAA stent-graft limb into the IIA. A femorofemoral crossover graft provided circulation to the leg ipsilateral to the IIA stent-graft, and the EIA on the same side was ligated. The technique can also be modified to treat isolated bilateral CIA aneurysms. Conclusions: By extending the distal aspect of the stent-graft into an IIA, bilateral CIA aneurysms can be excluded while preserving pelvic circulation on one side. J Endovasc Ther Key words: abdominal aortic aneurysm, endovascular repair, stent-graft, technique, common iliac artery, internal iliac artery, external iliac artery, coil embolization Endovascular aneurysm repair (EVAR) has become a well-established method over the past decade, and midterm results imply that the technique offers a relatively safe way to exclude aneurysms with less invasiveness compared to open surgery. 1 In cases of aneurysm disease with unilateral involvement of the common iliac artery (CIA), exclusion of the aneurysm is achieved by extending the stentgraft across the origin of the internal iliac artery (IIA) to reach a distal attachment site in the external iliac artery (EIA). To prevent retrograde flow into the aneurysm sac, the IIA is embolized. 2 The same technique can be ap- Address for correspondence and reprints: Martin Delle, MD, PhD, Department of Radiology, South Stockholm General Hospital, Sjukhusbacken 10, SE Stockholm, Sweden. Fax: ; m.delle@bostream.nu 2005 by the INTERNATIONAL SOCIETY OF ENDOVASCULAR SPECIALISTS Available at

2 190 STENT-GRAFT TREATMENT OF AORTOILIAC ANEURYSMS Figure 1(A) After embolization of the left IIA, a bifurcated Excluder stent-graft was deployed via a surgically exposed CFA. The left stent-graft limb was extended to the EIA. (B) A right stent-graft limb was first placed from a right femoral approach with the distal end inside the CIA aneurysm. Then, via a 10-F introducer in the left brachial artery, the right stent-graft limb was extended into the IIA in an antegrade fashion. The procedure was completed with a surgical femorofemoral crossover graft and ligation of the right EIA. plied when treating IIA aneurysms as well; however, the coils are then placed in internal iliac branches distal to the aneurysm. Unilateral occlusion of the IIA is rarely associated with serious ischemic complications; gluteal claudication is, however, frequently reported. 3 Endovascular treatment of bilateral CIA aneurysms extending to the iliac bifurcation is often inappropriate since the technique described above will result in occlusion of the IIAs bilaterally, which may increase the risk for pelvic and/or colonic ischemia. 4 Thus, surgery has often been the treatment of choice to preserve IIA circulation. Recently, endovascular alternatives have been described in terms of stent-graft connection between the EIA and IIA in combination with a contralateral aortomonoiliac stent-graft, 5,6 as well as branched iliac stent-grafts. These techniques are limited by certain anatomical criteria; however, we developed an alternative endovascular technique for aneurysm exclusion that preserves pelvic circulation on one side in patients with bilateral CIA aneurysms (with or without concomitant abdominal aortic aneurysm [AAA]). TECHNIQUE Unilateral IIA embolization 7 with microfilament metal coils (MReye embolization coil; William Cook Europe, Bjaeverskov, Denmark) was performed either prior to or in the same session as the stent-graft procedure, depending on whether or not a lengthy intervention was anticipated due to tortuous vessel anatomy. For aortoiliac aneurysms, Excluder bifurcated stent-grafts (W.L. Gore & Associates, Flagstaff, AZ, USA) oversized by 10% to 20% were used to exclude the AAA. Prophylactic antibiotics (cloxacillin sodium; AstraZeneca, Stockholm, Sweden) were given intravenously to all patients 2 hours before the stent-graft procedure. Heparin ( units) was administered at the beginning of the procedure, followed by 1000 U/h throughout the session. With the patient under general anesthesia, both common femoral arteries (CFA) were surgically exposed. The stent-graft main body was introduced and deployed with the proximal end just below the renal arteries (Fig. 1A). On the ipsilateral side, the stent-graft limb was extended 3 cm beyond the orifice of the

3 STENT-GRAFT TREATMENT OF AORTOILIAC ANEURYSMS 191 Figure 2(A) Preoperative 3D reformatted computed tomogram demonstrating aneurysms of the infrarenal aorta, both CIAs, and left IIA. (B) Final angiogram after embolization of the left IIA and deployment of a bifurcated stent-graft with the left limb extending into the EIA and the right limb into the CIA. Via a left brachial approach, a stent-graft was positioned connecting the right stent-graft limb with the IIA. embolized IIA into the EIA using an Excluder stent-graft limb extender. On the contralateral side (Fig. 1B), the stent-graft limb was deployed so that the distal end was 10 to 15 mm proximal to the patent IIA orifice. The IIA was then selectively catheterized in an antegrade fashion via a surgically exposed left brachial artery access. Stent-grafts were then deployed via an 8 to 12-F introducer to span the distance from the distal end of the contralateral AAA stent-graft limb into the IIA. The type of stent-graft used (usually Hemobahn [W.L. Gore & Associates], Wallgraft [Boston Scientific, Natick, MA, USA], or Jomed stent-grafts [Abbott Scandinavia AB, Solna, Sweden] depended on tortuosity and the diameters of the iliac vessels. The stent-graft procedure was followed by a femorofemoral crossover graft to achieve adequate circulation to the leg ipsilateral to the IIA stent-graft. The EIA on the same side was ligated slightly above the level of the inguinal ligament to prevent retrograde flow into the aneurysm from the CFA. We have used this technique in 5 patients thus far, with excellent results (Fig. 2). We also encountered 2 patients who had unilateral IIA aneurysms in addition to bilateral CIA aneurysms; these patients were not treated with bifurcated stent-grafts because the proximal attachment sites in the CIA were adequate (width 14 mm, length 15 mm). In these cases, an arterial lumen diameter of 14 mm at the proximal attachment site was accepted since the proximal diameter of the Excluder stent-graft limbs and extenders was 16 mm. We regarded a 2-mm oversizing as sufficient for an adequate seal in these cases. In these patients, the branches distal to the IIA aneurysm were embolized as described above to avoid retrograde flow into the aneurysm. 8 Iliac stent-graft placement was performed through transfemoral 10 to 12-F introducer sheaths. The proximal attachment site of the CIA ipsilateral to the embolized IIA was connected to the EIA using Excluder stentgraft limb extenders (Fig. 3A). An Excluder limb extender was then placed from the proximal neck of the contralateral CIA so that its distal end was positioned within the CIA aneurysm 10 to 15 mm proximal to the patent IIA orifice. (An Excluder leg extender was used here because of its shorter length [70 mm] compared with a stent-graft limb.) Via a crossover approach, the IIA was then catheterized through this stent-graft, and a inch Amplatz super stiff crossover guidewire (Cordis, a Johnson and Johnson company, Sollentuna, Sweden) was left in place. An additional stent-graft was then advanced across the aortic bifurcation and positioned in an antegrade fashion into the IIA, connecting the CIA stent-graft to the IIA (Fig. 3B). Balloon di-

4 192 STENT-GRAFT TREATMENT OF AORTOILIAC ANEURYSMS Figure 3Drawing of the procedure for exclusion of two isolated CIA aneurysms and one left IIA aneurysm using a bilateral CFA approach. (A) After embolization of the left IIA, stentgrafts were placed from the proximal left CIA to the EIA. (B) A right CIA stent-graft was first placed from a right femoral approach, with the distal end in the aneurysm. A second stentgraft was introduced from the left CFA over the aortic bifurcation connecting the right CIA stent-graft with the right IIA. This was followed by surgical ligation of the right EIA and a femorofemoral crossover graft. Figure 4(A) Preoperative iliac angiogram showing aneurysms of both CIAs and the left IIA. (B) Postoperative angiogram demonstrating exclusion of the aneurysms following embolization of the left IIA, a left-sided CIA-EIA stent-graft, and a right-sided CIA-IIA stent-graft, followed by ligation of the right EIA and a femorofemoral graft supplying the right leg. lation was performed at the proximal and distal attachment sites and in the overlapping zones. For these procedures (Fig. 4), we used Excluder legs and extenders, Hemobahn stent-grafts, and a custom-made stent-graft limb from of a Zenith system (Cook Europe). Of the 7 patients treated thus far in this manner, one developed an infection in the groin incisions, which progressed to involve the crossover graft. The patient was treated with intravenous broad-spectrum antibiotics and was discharged 3 weeks postoperatively on chronic oral antibiotic treatment. In another case, a type I endoleak was detected in the distal right CIA due to a too short attachment site. During a secondary intervention, the endoleak was sealed with a stent-graft extension into the right IIA via a brachial approach. At up to 36 months (minimum 8), all stentgrafts remain patent; no secondary intervention has been needed to maintain patency of the IIA. During follow-up, 13 aneurysms decreased in size, 7 remained unchanged, and 1 increased in size owing to a type II endoleak from the inferior mesenteric artery (IMA). Coil

5 STENT-GRAFT TREATMENT OF AORTOILIAC ANEURYSMS 193 embolization via direct translumbar puncture of the aneurysm sac obliterated the leak. DISCUSSION The present study describes a novel endovascular technique that preserves pelvic circulation following stent-graft treatment of aneurysmal disease including bilateral iliac aneurysms. The technique of extending the stent-graft distally into the IIA on one side can be applied in patients with AAA in combination with iliac aneurysms, as well as in subjects with isolated bilateral CIA aneurysms. Unilateral IIA embolization and stent-graft extension to the EIA to exclude a unilateral CIA aneurysm has been described previously. 7,9 However, ischemic complications, such as buttock claudication, sexual dysfunction, and more rarely, mesenteric ischemia, have been observed in 12% to 45% of the patients. 4,9 12 Four (57%) of the 7 patients we treated with our technique suffered from hip/ gluteal claudication ipsilateral to the embolized IIA during the first year. There was subjective relief of these symptoms at 12 months, and only one patient had mild symptoms during physical exercise. No severe ischemic complications, such as mesenteric ischemia and/or gluteal/pelvic necrosis, occurred. The variable occurrence of ischemia following IIA occlusion may be explained by several factors. The location of the coils within the IIA seems to be of importance. Kritpracha et al. 3 reported that placement of coils in the proximal part of the IIA reduces the incidence of gluteal claudication compared to more distal embolization in the IIA branches. Factors affecting collateral circulation, such as patency of the IMA, the contralateral IIA, and the ascending branches from the ipsilateral deep femoral artery, are also important to the outcome. 10,13 In general, symptoms of gluteal claudication after unilateral IIA occlusion are transient due to development of collateral circulation. 14 Bilateral occlusion of the hypogastric circulation may be associated with increased risk of gluteal ischemia and severity of ischemic symptoms, such as bowel ischemia and hip necrosis. 13 Even though there are studies that report few serious ischemic complications of bilateral IIA occlusion, 12 most authors agree that flow in at least one IIA should be maintained if at all possible. 4,14 This could be of extra importance if bifurcated stent-grafts are used, since these occlude the IMA, which otherwise would have the potential for recruitment of collateral vessels to the pelvic region. Faris et al. 15 described a surgical procedure for IIA revascularization after stent-graft repair in which the IIA on one side is bypassed from the EIA, either with a synthetic graft or direct EIA-IIA end-to-side anastomosis via a retroinguinal or retroperitoneal incision. The contralateral IIA was embolized. The technique allows endovascular repair of aneurysms in patients who otherwise could be at risk for developing complications associated with bilateral IIA disruption. A similar technique with hypogastric bypass was described recently. 16 However, solving this problem with endovascular techniques by extending the stent-graft distally on one side into the IIA, as we described here, appears less invasive than an open abdominal intervention. Although our method still necessitates a surgical femorofemoral bypass with its potential complications, our approach avoids intra-abdominal surgery. An endovascular alternative for maintenance of unilateral IIA patency has been reported. 5,6 These authors described a retrograde stent-graft connection between the EIA and IIA in combination with an aortomonoiliac stent-graft directed to the contralateral EIA. In this case, flow into the EIA and IIA was maintained through a femorofemoral crossover graft. A few cases with this technique have been performed at our institution as well, with satisfactory outcome. However, our experience has found a large group of patients who have an overly acute angle between the two vessels, which contributes to both technical difficulties in positioning the stent-graft as well as potential kinking after deployment. The alternative of a crossover route over the bifurcation via the bifurcated stent-graft to reach the EIA is not possible due to the sharp angle between the stent-graft limbs. In contrast, a left brachial approach offers the advantage of a relatively straight route for positioning the stent-graft in the iliac

6 194 STENT-GRAFT TREATMENT OF AORTOILIAC ANEURYSMS artery. We did not notice any cerebral or other embolic events from catheterization of the left brachial artery, but caution should be exercised if preprocedural imaging reveals mural thrombi or advanced calcifications in the left subclavian and/or axillary region. If introducers larger than 8-F are used, a surgical cutdown of the brachial artery is recommended to avoid damage to the artery. In several cases, a discrepancy between the IIA diameter and the diameter of the proximal attachment site in the CIA was present. The large difference between distal and proximal attachment sites necessitated distally telescoping several stent-grafts of decreasing diameter. A large discrepancy between the stent-graft size and the diameter of the attachment site may cause wrinkles in the graft fabric, which in turn increase the risk for endoleak and thrombotic complications. The anatomical challenges also necessitated combining different stent-graft models of varying flexibility, profile, and delivery technique. During follow-up, we did not notice any drawbacks or complications due to this mix of devices, but special attention should be given to this situation during long-term follow-up. Conclusions This technique for endovascular management of aortoiliac aneurysmal disease with bilateral CIA involvement lowers the risk for ischemic complications associated with bilateral IIA occlusion by extending the stentgraft into the IIA on one side, while the contralateral IIA is embolized. Connection between the stent-grafts in the CIA and the IIA can be performed either via the left brachial artery or, in cases of isolated IIA aneurysms, via an aortic bifurcation crossover route. Although more than half of our patients experienced hip/gluteal claudication following the procedure, the symptoms subsided during follow-up. However, based on our very limited experience with this technique, conclusions regarding the true frequency of ischemic consequences after unilateral IIA occlusion cannot be made. REFERENCES 1. Ouriel K, Clair DG, Greenberg RK, et al. Endovascular repair of abdominal aortic aneurysms: device-specific outcome. J Vasc Surg. 2003;37: Cynamon J, Lerer D, Veith FJ, et al. Hypogastric artery coil embolization prior to endoluminal repair of aneurysms and fistulas: buttock claudication, a recognized by possibly preventable complication. J Vasc Interv Radiol. 2000; 11: Kritpracha B, Pigott JP, Price CI, et al. Distal internal iliac artery embolization: a procedure to avoid. J Vasc Surg. 2003;37: Karch LA, Hodgson KJ, Mattos MA, et al. Adverse consequences of internal iliac artery occlusion during endovascular repair of abdominal aortic aneurysms. J Vasc Surg. 2000;32: Bergamini RM, Rachel ES, Kinney EV, et al. External iliac artery-to-internal iliac artery endograft: a novel approach to preserve pelvic inflow in aortoiliac stent grafting. J Vasc Surg. 2002;35: Ayerdi J, McLafferty RB, Solis MM, et al. Retrograde endovascular hypogastric artery preservation (REHAP) and aortouniiliac (AUI) endografting in the management of complex aortoiliac aneurysms. Ann Vasc Surg. 2003;17: Razavi MK, Dake MD, Semba CP, et al. Percutaneous endoluminal placement of stent-grafts for the treatment of isolated iliac artery aneurysms. Radiology. 1995;197: Mori M, Sakamoto I, Morikawa M, et al. Transcatheter embolization of internal iliac artery aneurysms. J Vasc Interv Radiol. 1999;10: Razavi MK, DeGroot M, Olcott C, et al. Internal iliac artery embolization in stent-graft treatment of aortoiliac aneurysms: analysis of outcomes and complications. J Vasc Interv Radiol. 2000;11: Yano OJ, Morrissey N, Eisen L, et al. Intentional internal iliac artery occlusion to facilitate endovascular repair of aortoiliac aneurysms. J Vasc Surg. 2001;34: Lee CW, Kaufman JA, Fan CM, et al. Clinical outcome of internal iliac artery occlusions during endovascular treatment of aortoiliac aneurysmal disease. J Vasc Interv Radiol. 2000;11: Mehta M, Veith FJ, Ohki T, et al. Unilateral and bilateral hypogastric artery interruption during aortoiliac aneurysm repair in 154 patients. A

7 STENT-GRAFT TREATMENT OF AORTOILIAC ANEURYSMS 195 relatively innocuous procedure. J Vasc Surg. 2001;33(2 Suppl):S Iliopoulos JI, Hermreck AS, Thomas JH, et al. Hemodynamics of the hypogastric arterial circulation. J Vasc Surg. 1989;9: Rhee RY, Muluk SC, Tzeng E, et al. Can the internal iliac artery be safely covered during endovascular repair of abdominal aortic and iliac artery aneurysms? Ann Vasc Surg. 2002;16: Faries PL, Morrissey N, Burks JA, et al. Internal iliac artery revascularization as an adjunct to endovascular repair of aortoiliac aneurysms. J Vasc Surg. 2001;34: Arko FR, Lee WA, Hill BB, et al. Hypogastric artery bypass to preserve pelvic circulation: improved outcome after endovascular abdominal aortic aneurysm repair. J Vasc Surg. 2004; 39: