Abstract: Objective：To study the importance of the internal iliac artery (IIA) during the endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA). Methods: Forty-six consecutive cases of AAA treated by EVAR were retrospectively analyzed. The complications after exclusion of the IIA were analyzed. Results: The bilateral IIAs were reserved in 18 cases, in which the follow-up was achieved in 16 cases and no complication was observed. The IIAs were excluded in 28 (60.9%) cases, in which the bilateral, right and left IIAs were excluded in 7 (15.2%), 14 (30.4%) and 7 (15.2%) cases respectively. The follow-up was achieved in 26 cases. Buttock claudication was observed in 12 (46.2%) cases, altered bowel habit was observed in 8 (32.0%) cases, erectile dysfunction was observed in 3 (12.0%) cases, and bloody stool was observed in 2 (8.0%) cases. Comparing the bilateral and unilateral IIA exclusions, the rates of buttock claudication were 50.0% vs. 45.0%, altered bowel habit 33.3% vs. 31.6%, and erectile dysfunction 33.3% vs. 5.3% respectively. And the average duration of buttock claudication of bilateral IIAs exclusion (8.3 months) was longer than that of unilateral exclusion (4.7 months). Moreover, comparing the left and right IIA exclusions, the rates of buttock claudication were 57.1% vs. 38.5%, altered bowel habit 57.1% vs. 16.7%, and bloody stool 28.6% vs. 0 respectively. And the average duration of buttock claudication of left IIA exclusion (6.0 months) was longer than that of right exclusion (3.7 months). Conclusion: The IIAs, especially the left IIA, should be reserved during the EVAR for AAA.

Key words: Aortic aneurysm, abdominal, Angioplasty, Iliac artery, Postoperative complications