Common Iliac Artery Occlusion with Use of Gianturco Coils and Ethylene Vinyl Alcohol Liquid Embolization Agent before Aortouniiliac Stent-Graft Deployment

Abstract

Editor: Some patients who are otherwise candidates for endovascular abdominal aortic aneurysm (AAA) repair cannot be treated with a bifurcated graft because of severe tortuosity, calcification, or occlusion of a common or external iliac artery. An aortouniiliac device can be used in these patients (1), but it is necessary to occlude the contralateral common iliac artery (CIA) to prevent back perfusion of the aneurysm sac. We describe the use of a liquid embolization agent, Onyx (ethylene vinyl alcohol copolymer; Micro Therapeutics, Irvine, CA), in combination with Gianturco steel coils (Cook, Bloomington, IN) to occlude the contralateral common iliac artery before aortouniiliac endovascular AAA repair. An 82-year-old man presented with an asymptomatic 7.0-cm infrarenal AAA. The presence of a 5-cm-long left external iliac artery occlusion precluded insertion of a bifurcated stent-graft. The patient’s left CIA and internal iliac arteries were patent. It was decided to treat the patient with an aortouniiliac stent-graft (Talent; World Medical, Sunrise, FL) and a right-to-left femorofemoral crossover graft. To achieve left common iliac artery occlusion, we elected to use Gianturco coils (Cook, Bloomington, IN) and Onyx (Micro Therapeutics). Permission to use this investigational liquid embolic agent was received from the Health Protection Board of Canada. The procedure was performed under general anesthesia in the angiography suite. After right common femoral artery cutdown, a 5-F Cobra catheter (Cordis, Miami, FL) was directed from the right iliac system into the left common iliac artery. Four 5-cm 8-mm Gianturco coils were deployed just proximal to the internal iliac artery origin. Although this slowed flow within the CIA, the vessel remained patent. Two milliliters of Onyx were then delivered via a coaxial 3-F microcatheter (Rebar 14; Micro Therapeutics) proximal to the Gianturco coils. Total occlusion of the left common iliac artery was achieved (Fig 1). The stent-graft was delivered through an arteriotomy in the right common femoral artery and was deployed in the usual manner without incident (Fig 2). Completion angiography and computed tomography (CT) of the abdomen performed the next day showed complete exclusion of the AAA with no evidence of endoleaks (Fig 3). There was no flow across the embolized left common iliac artery. Follow-up CT at 3, 6, and 9 months after stent-graft implantation continued to show no evidence of endoleak. The 6and 9-month studies demonstrated reduction in AAA size to 6.7 cm and 6.3 cm, respectively. Several mechanical occlusion devices have been used to occlude the contralateral CIA before endovascular AAA repair with an aortouniiliac graft, but a large delivery device is typically used, which requires ipsilateral delivery through an arteriotomy. Patients with an external iliac artery occlusion cannot be treated in this manner. The use of vascular coils to occlude the CIA has been reported, and this can be performed with use of a contralateral approach. However, recanalization through the interstices of coils can occur, and we were concerned that vascular coils would not provide as robust an occlusion as we required. Concern about the possibility of recanalization prompted us to use a liquid embolic agent as well as coils. We believed that use of a liquid agent would limit the risk of recanalization because a liquid agent Figure 1. Digital subtraction angiogram of the left common iliac artery after embolization showed complete occlusion of the artery. The polymerized Onyx has formed a cast of the artery above the Gianturco steel coils. Letters to the Editor