Clinical outcomes after internal iliac artery embolization prior to endovascular aortic aneurysm repair

Background: Aortic anatomy is important in determining the success or failure of endovascular aortic aneurysm repair (EVAR). Endoleak is another issue which should be addressed for a long-term durability of the procedure. Internal iliac artery (IIA) embolization is required to prevent type II endoleak when the iliac landing zone is not sufficient such that the iliac limb should be extended down to the external iliac artery (EIA). Pelvic ischemia is an important complication of IIA embolization, but its incidence and severity is not exactly known. Our experience suggests this to be common but not severe. In this study we reviewed the clinical outcomes of patients who underwent HA embolization to facilitate EVAR at one of the major tertiary medical centers in South Korea. Methods: We performed a retrospective review of the patients who underwent IIA embolization prior to EVAR between November 2005 and June 2018 at a single tertiary medical center in South Korea. Patients were interviewed via telephone to determine the severity of buttock claudication according to a previously defined pain scale. Results: The majority of 139 patients in both the unilateral and bilateral IIA embolization groups experienced no (N.=83, 60.0%) or mild (N.=51, 36.7%) buttock claudication. Only three patients in the unilateral IIA embolization group reported that their symptoms affected daily life, but without need for any measures for pain relief. Symptom duration was longer in the bilateral embolization group (12.6 months) compared to the unilateral group (6.6 months) without statistical significance (P=0.559). There were no critical complications such as buttock necrosis, spinal cord ischemia, or ischemic colitis. Conclusions: Based on our experience, IIA embolization does cause buttock claudication of a certain degree. However, the most of them experienced mild discomfort rather than such symptoms severely affect their quality of life. Considering the risks of general anesthesia and complications of surgical procedures, IIA reconstruction along with EVAR may not be necessary.