Preservation of pelvic perfusion with iliac branch devices does not decrease ischemic colitis compared with hypogastric embolization in endovascular abdominal aortic aneurysm repair

Abstract

ObjectiveIschemic colitis is a rare but devastating complication of endovascular repair of infrarenal abdominal aortic aneurysms. Although it is rare (0.9%) in standard endovascular aneurysm repair (EVAR), the incidence increases to 2% to 3% in EVAR with hypogastric artery embolization (HAE). This study investigated whether preservation of pelvic perfusion with iliac branch devices (IBDs) decreases the incidence of ischemic colitis. MethodsWe used the targeted EVAR module in the American College of Surgeons National Surgical Quality Improvement Program database to identify patients undergoing EVAR of infrarenal abdominal aortic aneurysm from 2012 to 2017. The cohort was further stratified into average-risk and high-risk groups. Average-risk patients were those who underwent elective repair for sizes of the aneurysms, whereas high-risk patients were repaired emergently for indications other than asymptomatic aneurysms. Within these groups, we examined the 30-day outcomes of standard EVARs, EVAR with HAE, and EVAR with IBDs. The primary outcome was the incidence of ischemic colitis. Secondary outcomes included mortality, major organ dysfunction, thromboembolism, length of stay, and return to the operating room. The χ2 test, Fisher exact test, Kruskal-Wallis test, and multivariate regression models were used for data analysis. ResultsThere were 11,137 patients who had infrarenal EVAR identified. We designated this the all-risk cohort, which included 9263 EVAR, 531 EVAR-HAE, and 1343 EVAR-IBD procedures. These were further stratified into 9016 cases with average-risk patients and 2121 cases with high-risk patients. In the average-risk group, 7482 had EVAR, 411 had EVAR-HAE, and 1123 had EVAR-IBD. In the high-risk group, 1781 had EVAR, 120 had EVAR-HAE, and 220 had EVAR-IBD. There was no significant difference in 30-day outcomes (including ischemic colitis) between EVAR, EVAR-HAE, and EVAR-IBD in the all-risk and high-risk groups. In the average-risk cohort, EVAR-HAE was associated with a higher mortality rate than EVAR (2.2% vs 1.0%; adjusted odds ratio, 2.58; P = .01). Although EVAR-IBD was not superior to EVAR-HAE in 30-day mortality, major organ dysfunction, or ischemic colitis in this average-risk cohort, EVAR-IBD exhibited a trend toward lower mortality compared with EVAR-HAE in this cohort, but it was not statistically significant (1.0% vs 2.2%; adjusted odds ratio, 0.42; P = .07). ConclusionsIschemic colitis is a rare complication of EVAR. HAE does not appear to increase the risk of ischemic colitis, and preservation of pelvic perfusion with IBDs does not decrease its incidence. Although HAE is associated with significantly higher mortality than standard EVAR in average-risk patients, the preservation of pelvic perfusion with IBDs does not appear to improve mortality over HAE.