Intentional internal iliac artery occlusion to facilitate endovascular repair of aortoiliac aneurysms

Purpose: The safety of intentional occlusion of patent internal iliac arter ies (IIAs) to facilitate the endovascular repair of aortoiliac artery aneur ysms (abdominal aortic aneurysms [AAAs] and iliac aneurysms [IAs]) was eval uated. Methods. We analyzed the techniques and clinical sequelae of selective occl usion of one or both IIAs in 103 patients and correlated these findings wit h the results of preoperative angiograms to identify vascular anatomy that may predict postoperative pelvic ischemia. To quantify the clinical present ation of pelvic ischemia, we developed these criteria: class 0, no symptoms ; class I, nonlimiting claudication with exercise; class II, new onset impo tence, with or without moderate to severe buttock pain, leading to physical limitation with exercise; class III, buttock rest pain, colonic ischemia, or both. IIA occlusion was achieved in 100% of the patients by means of eit her catheter-directed embolization or orificial coverage with a stent-graft . No patient in this study had angiographic evidence of significant viscera l occlusive disease before the procedure. Sixty-four patients had isolated AAAs, 23 patients had AAAs and IAs, and 16 patients had isolated IAs. Ninet y-two patients had one IIA selectively occluded, and 11 patients had both I IAs selectively occluded. Results. After IIA occlusion, 12 patients were categorized in class I, 9 pa tients were categorized in class II, and 1 patient was categorized in class III, for a total of 22 patients (21%) with pelvic ischemia. Sixteen (17%) of 92 patients had unilateral IIA occlusions, and six (17%) of 11 patients had bilateral IIA occlusions. Five patients in class I improved and had no symptoms within I year, and one patient in class II was downgraded to class I because of improved symptoms. Two unique preoperative angiographic findi ngs were identified in the remaining 16 patients (16%) with chronic pelvic claudication: (1) stenosis of the remaining IIA origin (>70%) with nonopaci fication of more than three of the six I IA branches (63%); and (2) small c aliber, diseased or absent medial and lateral femoral circumflex arteries i psilateral to the side of the IIA occlusion (25%). One patient with class I II ischemia died of cardiovascular collapse associated with colon infarctio n caused by either acute ischemia or particulate embolization. Conclusion: The incidence of pelvic ischemia after IIA occlusion is 20% imm ediately after endovascular aortoiliac aneurysm repair. A total of 25% of p atients had no symptoms within 1 year. Two preoperative radiologic findings may help identify patients who are at risk for pelvic ischemia: stenosis o f the patent IIA and disease deep femoral ascending branches ipsilateral to the occluded IIA. The risk of colon ischemia appears to be small after sel ective IIA occlusion to facilitate endovascular AAA repair.