29 de agosto del 2015
Thomas Kotsis, MD, PhD; Antonis Tsanis, MD; Giorgos Sfyroeras, MD; Christos Lioupis, MD; Konstantinos Moulakakis, MD; and Panagiotis Georgakis, MD
Endovascular treatment of common iliac artery (CIA) aneurysms extending to the iliac bifurcation presents many difficulties due to anatomical limitations, since all the available stent-grafts require an adequate length of normal artery as a landing zone. Occasionally, both CIAs are aneurysmal, and stent-grafts need to extend to the external iliac arteries (EIA). Alternative endovascular techniques have been developed to maintain patency of at least one internal iliac artery (IIA)1–3 to avoid the ischemic complications that have been reported after bilateral IIA occlusion.4 All these techniques have been applied to patients with nonaneurysmal IIAs.
The concomitant presence of a unilateral IIA aneurysm raises additional technical difficulties, especially if occlusion of this particular IIA has to be avoided. In previously reported cases, IIA aneurysms have been excluded by stenting of the CIA and EIA or by coil embolization of the IIA.5 We have developed a technique to maintain flow to an aneurysmal IIA via a reverse-U stent-graft from the EIA when treating bilateral CIA aneurysms with an aortomonoiliac stent-graft and femorofemoral bypass.
We illustrate the technique in a 78-year-old man with bilateral CIA aneurysms and a right IIA aneurysm (Fig. 1 ). Both EIAs and CIAs were severely angulated (Fig. 2 ). The plan was to place a stent-graft from the right EIA to the right IIA (Fig. 3 ), coil embolize the left IIA, insert an aortomonoiliac graft to the left EIA, and construct a femorofemoral bypass. The common femoral arteries were surgically exposed, and 5000 units of heparin were administered. A 0.035-inch guidewire was advanced to the aorta from both sides. The left IIA was cannulated using a 5-mm vertebral guiding catheter (Glidecath; Terumo Europe N.V., Leuven, Belgium); a 16-mm sheath was advanced in the right EIA to straighten the vessel. A 5-F hydrophilic Simmons I catheter (Boston Scientific/Medi-tech, Natick, MA, USA) was used to catheterize the right IIA, and a 0.014-inch hydrophilic guidewire (Cougar XT; Radius Medical Technologies, Maynard, MA, USA) was advanced to a distal gluteal branch (Fig. 4A ). This wire was exchanged with a stiffer 0.025-inch wire (Radifocus Guide Wire M; Terumo Europe N.V.) to advance the stent-graft. In this particular case, we tried to advance the catheter into the IIA, but this proved very difficult because angulation of the right iliac bifurcation resulted in severe kinking of the catheter. A 14×40-mm balloon catheter (Agiltrac; Cook Inc., Europe, Bjaeverskov, Denmark) was then placed just proximal to the iliac bifurcation into the aneurysmal CIA and inflated gently; the balloon prevented kinking and forward movement of the catheter to the CIA and actually forced the catheter to advance into the gluteal branch (Fig. 4B ). The guidewire was exchanged with a 0.025-inch hydrophilic wire (Terumo, Tokyo, Japan), and the catheter was removed. An 11×5-mm Hemobahn stent-graft (W.L. Gore & Associates, Flagstaff, AZ, USA) was advanced while the aortic balloon remained inflated, and correct position of the stent-graft was confirmed by angiography. The aortic balloon was deflated and removed; the stent-graft was deployed and dilated with an 11×40-mm balloon. A second 11×5-mm Hemobahn stent-graft was deployed centrally in the EIA with a 2-cm overlap with the first device. Angiography revealed complete exclusion of the IIA aneurysm with no sign of endoleak. Coil embolization of the left IIA was then performed, resulting in occlusion and thrombosis of its origin (Fig. 4C ). A 34×16×170-mm Talent aortomonoiliac endograft and a 16×12×75-mm iliac extension (Medtronic Vascular, Santa Rosa, CA, USA) were deployed below the renal arteries extending to the left EIA; postdilation of the stent-graft was performed using a Reliant aortic balloon (Medtronic Vascular). Finally, a left-to-right femorofemoral bypass was constructed using an 8-mm polytetrafluoroethylene graft (W.L. Gore & Associates). Completion angiography revealed complete exclusion of the aneurysms (Fig. 4D ). Six-month follow-up in this particular case demonstrated patency of all grafts (Fig. 5 ).
The risks of bilateral IIA occlusion is well documented, and the principle of preserving at least one IIA continues to be predominant in vascular surgery. Different surgical techniques have been described for the preservation of pelvic circulation by maintaining flow to at least one IIA in the face of bilateral CIA aneurysms. Some authors have recommended a hybrid procedure in which the IIA on one side is bypassed from the EIA via a retroperitoneal or retroinguinal incision (either with a synthetic graft or direct EIA-IIA side-to-end anastomosis), and the contralateral IIA is embolized.[7,8] Alternatively, CIA aneurysm banding via a retroperitoneal approach or a hybrid endovascular procedure involving direct suturing of an aortoiliac stent-graft to the CIA bifurcation allows IIA perfusion without a distal type I endoleak. However, these procedures require extensive dissection, especially difficult in reoperative cases, that may lead to trauma of adjacent structures, hematoma formation, and infection, so they are not recommended for high-risk patients. They are also time-consuming compared to standard endovascular procedures and involve greater blood loss. Rupture of the arterial wall or embolization in the presence of intraluminal thrombus are two additional concerns in the case of CIA banding. The utility and long-term results of the aforementioned procedures are uncertain.
Delle et al. have described a novel method that preserves pelvic circulation by extending the stent-graft distally into the IIA on one side followed by surgical ligation of the EIA and a femorofemoral crossover graft; among the drawbacks of this method are the complications related to brachial artery catheterization and the discrepancy between the IIA diameter and the proximal and distal attachment sites (telescoping of several stent-grafts of decreasing diameter may cause wrinkles in the fabric, endoleak, and thrombotic events). An alternative approach for preserving pelvic circulation is the sequential coil embolization of the IIAs exactly at their point of origin in an attempt to encourage collateralization prior to stent-graft deployment; this requires usually a few weeks for the collaterals to develop before aneurysm repair and, of course, involves a further invasive procedure. Although published and unpublished data stress the uneventful outcome of bilateral coil embolization, the issue of bilateral IIA embolization remains controversial, with most vascular surgeons continuing to regard it a highly risky or contraindicated procedure.
Abraham et al. have described a modular stent-graft for cases of bilateral common iliac aneurysms. Introduction of a stent-graft that bridges the gap between the bifurcated CIA component and the IIA is technically demanding. When the approach from the brachial artery is used, there is a risk of embolic events; when the opposite femoral artery path is chosen, many difficulties may be encountered due to calcified iliac arteries and a narrow aortic bifurcation angle. Combined endovascular bifurcated and branched stent-graft placement was used by Iwase et al. to repair an abdominal aortic aneurysm involving both CIAs. Although the use of branched stent-grafts with iliac bifurcations seems the ideal endovascular therapy, use of these sophisticated endografts has yet to be established.
Several reports have described maintenance of pelvic perfusion by inserting an aortomonoiliac stent-graft on the ipsilateral side with a crossover bypass and linking the contralateral internal and external iliac arteries with a covered stent. Hoffer et al. first used an EIA to IIA covered stent to exclude the distal aspect of a left CIA aneurysm. Derom et al. employed the same method with a Hemobahn stent-graft to exclude bilateral CIA stump aneurysms in a patient with prior aortic tube graft, aortobifemoral bypass, and ligated bilateral CIA aneurysms. Clarke et al. reported another case in a patient with bilateral CIA aneurysms after open AAA repair; a Wallgraft endoprosthesis was deployed with the distal end in the left IIA and the proximal end within the left EIA. Finally, Bergamini et al. reported 4 cases of EIA-to-IIA endograft placement in patients with grade IIC AAA that had bilateral CIA aneurysms extending to the bifurcation; they achieved good short-term results, but the authors suggested that the IIA and EIA must not be aneurysmal.
Our decision to place an endograft in the aneurysmal IIA instead of coil embolization and retrograde flow interruption was based on anecdotal evidence supporting the notion that complications may occur more frequently when coils are placed distally into secondary and tertiary branches. We chose to preserve flow in these branches and made an effort to carefully occlude with coils the main trunk of the nonaneurysmal IIA, thus preserving patency in the extensive network of collaterals with the EIA, femoral artery, and contralateral IIA. The vessels distal to the embolization site continued to fill via collaterals, preventing pelvic ischemia. If we had proceeded to occlude the distal branches of the aneurysmal IIA where the deep femoral ascending branches were more diseased, the risk of ipsilateral pelvic ischemia would have been much higher. Moreover, it was our estimation that collateral vessels from external iliac–deep femoral ascending branches were better developed on the side of the occluded IIA; however, coils had slipped away in more peripheral branches with no clinical significance.
The extension of the aneurysm to the right IIA created a broad neck between the origin of the EIA and the IIA, and this broad neck allowed a smoother curve of the endograft, avoiding any kinking and subsequent thrombosis. The severe angulation of the left iliac bifurcation was considered prohibitive for stent-graft advancement into the IIA in this case. Two technical tips should be noted for overcoming the obstacle of EIA tortuosity ipsilateral to the aneurysmal IIA and catheter entry into the aneurysmal IIA; first, we used a long sheath up to the iliac bifurcation, and we inflated a balloon in the ipsilateral CIA.
We successfully excluded the aneurysm and maintained patency of the aneurysmal IIA by endografting because of the existence of a distal IIA neck in this case. To our knowledge, the exclusion of an IIA aneurysm with this technique has not been published before. However, a larger experience and longer follow-up is needed to determine the benefits of the method, assuming that the anatomical conditions allow it. Avoiding surgical exposure of the iliac arteries with the accompanying morbidity of retroperitoneal approaches is significantly advantageous. More flexible endografts delivered through smaller sheaths may minimize the theoretical risks of distal embolization and injury to the IIA and EIA. Should the patient be at high operative risk, an endovascular repair with retrograde (reverse-U stent-graft) hypogastric artery preservation must be considered a first choice until the use of iliac branched stent-grafts becomes more widespread.
Abdominal CT scans revealed bilateral common iliac artery aneurysms with a right internal iliac artery aneurysm.
Angiography demonstrated severe angulation and kinking of both common and external iliac arteries.
teps in this technique. (1) A right EIA-to-IIA stent-graft is placed, landing distal of the IIA aneurysm. (2) Left IIA coil embolization. (3) An aortomonoiliac stent-graft will extend to the left EIA, and (4) a femorofemoral bypass will be constructed.
(A) Catheterization of the right IIA and advancement of the guidewire to a distal gluteal branch. (B) A 14×40-mm balloon was gently inflated to the iliac bifurcation to prevent kinking and forward movement of the catheter into the CIA, forcing the catheter to advance into the aneurysmal IIA. (C) The 2 stent-grafts are in place. Coil embolization of the left IIA is performed. (D) Completion angiography reveals complete exclusion of the aneurysms.
Abdominal CT scan 6 months after the intervention demonstrates good patency of all grafts.
Autor: Thomas Kotsis, MD, PhD; Antonis Tsanis, MD; Giorgos Sfyroeras, MD; Christos Lioupis, MD; Konstantinos Moulakakis, MD; and Panagiotis Georgakis, MD
Fuente: Journal of Endovascular Therapy: Vol. 13, No. 2, pp. 158–163.
Ultima actualizacion: 1 DE AGOSTO DE 2007