Clinical Outcomes of Internal Iliac Artery Interruption during Endovascular Aneurysm Repair

PURPOSE: This study aimed to investigate the clinical outcomes of internal iliac artery (IIA) interruption during endovascular aneurysm repair (EVAR) and to identify the risk factors for ischemic complications. MATERIALS AND METHODS: Endovascular treatment was performed in 316 patients with aneurysms or pseudoaneurysms of the abdominal aorta or iliac arteries between March 2006 and January 2022. Medical records and radiological imaging studies were retrospectively reviewed. The incidences of buttock claudication, ischemic colitis, and spinal cord ischemia after IIA interruption were investigated as clinical outcomes. Binary logistic regression analysis were performed to identify the risk factors. RESULTS: IIA embolization was performed in 78 patients. Among the 42 patients who underwent IIA flow preservation procedures, the one-month computed tomography detected early failure in five patients. The origin of the IIA was covered with an endograft in ten patients who did not undergo embolization. Eventually, interruption of the IIA by EVAR was observed in 93 patients. Considering preoperative IIA occlusion, there was a total of six patients who did not have at least one IIA patency. Buttock claudication occurred in 32.6% of the patients, and none of the patients had ischemic colitis or spinal cord ischemia. In multivariable analysis, age ≤80 years and isolated iliac artery aneurysm were associated with the development of postoperative buttock claudication. CONCLUSION: The most common complication after IIA interruption is buttock claudication; however, critical complications such as ischemic colitis or spinal cord ischemia are rare, even in bilateral IIA occlusion. Adjunctive procedures to preserve bilateral IIA perfusion should be adopted selectively.