Predicting Visceral Aortic Growth After Infrarenal Abdominal Aortic Aneurysm Repair

Abstract

The objective of this study was to identify predictors of aortic aneurysm growth above an infrarenal abdominal aortic aneurysm (AAA) repair. This was a single-center, retrospective cohort study that examined 881 infrarenal AAA repairs from 2004 to 2008 and identified 187 of the repairs with preoperative and postoperative imaging at least 1 year from repair to evaluate aortic growth after infrarenal AAA repair. Preoperative and postoperative computed tomography (CT) imaging measured aortic diameters at the celiac, superior mesenteric, and renal arteries. Preoperative CT imaging also measured aortic thrombus and calcification volumes in the visceral and infrarenal abdominal aortic segments. Multivariable modeling was used with log-transformed variables to determine potential predictors of future aortic aneurysm development after infrarenal AAA repair. Of the 187 patients in the cohort, 100 had an open AAA repair; 87 had an endovascular AAA repair. Visceral aortic wall degeneration, defined as >5 mm of growth within the visceral aortic segment after infrarenal AAA repair, occurred in 27% of the cohort during an average of 72 ± 34.2 months of follow-up within the health care system. During the same follow-up period, 26% of the cohort developed aortic aneurysms above the infrarenal AAA repair. After multivariable modeling, visceral segment aortic thrombus on preoperative CT imaging was associated with an increased risk of aortic aneurysm development above the infrarenal AAA repair within both the open (hazard ratio [HR], 2.04; P = .033) and endovascular (HR, 3.31; P = .004) repair cohorts. Endovascular repair was found to be associated with a higher risk of future aortic aneurysm development after infrarenal AAA repair compared with open repair (HR, 2.19; P = .025; Fig). Visceral aortic dilation is common after infrarenal aortic repair. Visceral aortic thrombus present before infrarenal AAA repair and endovascular repair is associated with an increased risk of future aortic aneurysm development after infrarenal AAA repair. These factors may predict future failures for complex juxtarenal repairs with chimney and fenestrated endovascular aneurysm repair.