Risk Analysis of Aneurysm Sac Enlargement Caused by Type II Endoleak after Endovascular Aortic Repair

•Chronic kidney disease, inferior mesenteric artery (IMA), and lumbar arteries were risk factors for aneurysm sac enlargement.•Patent IMA seemed to have the greatest impact on long-term aneurysm sac enlargement.•Prognosis of patient with occluded IMA was quite good. BackgroundAlthough the preoperative risk factors associated with the occurrence of type II endoleak (ETII) after endovascular aortic repair (EVAR) have gradually become more evident, the preoperative risk factors associated with aneurysm sac enlargement caused by ETII remain unclear. This study aimed to determine the preoperative risk factors associated with aneurysm sac enlargement caused by ETII after EVAR.MethodsThis retrospective cohort study reviewed 519 EVARs performed for true abdominal aortic aneurysm between January 2006 and December 2018 at our institution. EVARs using commercially available bifurcated devices with no type I or III endoleaks during follow-up and with ≥12 months follow-up were included. A total of 320 patients were enrolled in the study. To identify the preoperative risk factors of sac enlargement after EVAR, Cox regression analysis was used to assess preoperative data.ResultsThe median follow-up period was 60.8 months. Overall, 135 of 320 patients (42%) had ETII during follow-up, and 47 of 135 patients (35%) developed aneurysm sac enlargement. Multivariate analysis revealed that chronic kidney disease (CKD) stage ≥4 (hazard ratio HR, 4.65; 95% confidence interval CI, 2.13–10.15; P = 0.001), patent inferior mesenteric artery (IMA) (HR, 17.85; 95% CI, 2.46–129.73; P< 0.001), and number of patent lumbar arteries (LAs) (HR, 1.37; 95% CI, 1.13–1.68; P= 0.002) were risk factors of aneurysm sac enlargement caused by ETII.ConclusionsCKD stage ≥4, patent IMA, and number of patent LAs were independent risk factors for aneurysm sac enlargement after EVAR. In particular, patent IMA had the highest HR and seemed to have the greatest impact on long-term aneurysm sac enlargement. Hence, taking preoperative measures to address a patent IMA appears to be important in reducing the incidence of sac enlargement. Although the preoperative risk factors associated with the occurrence of type II endoleak (ETII) after endovascular aortic repair (EVAR) have gradually become more evident, the preoperative risk factors associated with aneurysm sac enlargement caused by ETII remain unclear. This study aimed to determine the preoperative risk factors associated with aneurysm sac enlargement caused by ETII after EVAR. This retrospective cohort study reviewed 519 EVARs performed for true abdominal aortic aneurysm between January 2006 and December 2018 at our institution. EVARs using commercially available bifurcated devices with no type I or III endoleaks during follow-up and with ≥12 months follow-up were included. A total of 320 patients were enrolled in the study. To identify the preoperative risk factors of sac enlargement after EVAR, Cox regression analysis was used to assess preoperative data. The median follow-up period was 60.8 months. Overall, 135 of 320 patients (42%) had ETII during follow-up, and 47 of 135 patients (35%) developed aneurysm sac enlargement. Multivariate analysis revealed that chronic kidney disease (CKD) stage ≥4 (hazard ratio HR, 4.65; 95% confidence interval CI, 2.13–10.15; P = 0.001), patent inferior mesenteric artery (IMA) (HR, 17.85; 95% CI, 2.46–129.73; P< 0.001), and number of patent lumbar arteries (LAs) (HR, 1.37; 95% CI, 1.13–1.68; P= 0.002) were risk factors of aneurysm sac enlargement caused by ETII. CKD stage ≥4, patent IMA, and number of patent LAs were independent risk factors for aneurysm sac enlargement after EVAR. In particular, patent IMA had the highest HR and seemed to have the greatest impact on long-term aneurysm sac enlargement. Hence, taking preoperative measures to address a patent IMA appears to be important in reducing the incidence of sac enlargement.