The effect of demographic factors and lesion severity on iliac stent patency

Abstract

The aim of our study was to perform a large multivariate analysis to identify demographic, anatomic, or procedural factors that affect iliac artery stent primary patency (PP). Patients receiving iliac stents from 2007 to 2013 were retrospectively reviewed. Univariate analysis assessed cohort characteristics and their effect on PP. Variables considered significant (P < .05) were brought forward in the multivariate analysis. A total of 213 patients underwent primary iliac artery stenting, and 307 limbs were analyzed. The average age was 66 years (range, 38-93 years), 54% were male, and 55% were Caucasian. Indications for procedure were claudication in 68%, rest pain in 20%, and tissue loss in 12%. All TransAtlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC) II classifications were included: 51% TASC II A, 25% TASC II B, 13% TASC II C, and 11% TASC II D. The treated anatomic locations were 27% isolated external iliac artery (EIA), 56% isolated common iliac artery, and 17% combined common iliac artery and EIA. Multivariate analysis found three factors were correlated with decreased PP: non-Caucasian race (hazard ratio [HR], 1.84; 95% confidence interval [CI], 1.08-3.13; P = .025), younger age (HR, 1.04; 95% CI, 1.01-1.08; P = .006), and presence of EIA occlusion (HR, 2.02; 95% CI, 1.05-3.89; P = .036). Overall, Kaplan-Meier analysis at 1 and 3 years revealed a PP of 86% and 53%, assisted PP of 98% and 89%, and secondary patency of 99% of 98%. Kaplan-Meier analysis showed PP at 1 year for was 91% Caucasian patients vs 77% for non-Caucasian (P = .001). PP was 75% in patients aged <60 years, 86% in patients aged 60-70 years, and 96% in patients aged >70 years, with a significant difference between all groups (P < .001). PP was significantly different for those with and without EIA occlusion (P = .002), with 1-year PP of 71% and 88%, respectively. In our experience with a large number of iliac interventions, younger age, non-Caucasian race, and EIA occlusion were strong predictors for loss of PP.