Objective: The TransAtlantic Inter-Society Consensus (TASC) document did not define the best treatment for moderately severe iliac artery lesions, ie, TASC type B and type C iliac lesions, because of insufficient solid evidence to make firm recommendations. The purpose of this study was to evaluate the influence of risk factors on outcome of iliac stenting and operative procedures used to treat TASC type B and type C lesions.
Methods: Over the 5 years from 1996 to 2001, 188 endovascular and direct aortoiliac surgical reconstruction procedures were performed in 87 women and 101 men with TASC type B and type C iliac lesions and chronic limb ischemia. The criteria prepared by the Ad Hoc Committee on Reporting Standards (Society for Vascular Surgery/International Society for Cardiovascular Surgery (SVS/ISCVS) were followed to define variables. Both univariate analysis (Kaplan-Meier method) and multivariate analysis (Cox proportional hazards model) were used to determine the association between variables, cumulative patency rate, limb salvage, and survival.
Results: Indications for revascularization were disabling claudication (73%), limb salvage (25%), and blue toe syndrome (2%). Patients in the surgery group (n = 52) had significantly higher primary patency rates compared with patients in the stent group (n = 136) at univariate analysis (Kaplan-Meier method, log-rank test; P =.015). Primary patency rates at 1, 3, and 5 years were 85%, 72%, and 64% after iliac stenting, and 89%, 86%, and 86% after surgical reconstruction, respectively. Univariate and multivariate Cox regression analysis enabled identification of poor runoff (ie, runoff score >5 for unilateral procedures or >2.5 for bilateral outflow procedures; relative risk, 2.5; 95% confidence interval [CI], 1.4-4.2; P =.001) as the only independent predictor of decreased primary patency in all patients. However, stratified analysis including only patients with poor runoff revealed that patients undergoing iliac stenting had significantly lower primary patency rates compared with those undergoing surgical reconstruction (Kaplan-Meier method, log-rank test; P =.05). External iliac artery disease and female gender were also identified as independent predictors of decreased primary stent patency.
Conclusions: Poor infrainguinal runoff is the main risk factor for decreased primary patency after surgical reconstruction and iliac stenting to treat TASC type B and type C iliac lesions. However, primary patency is less affected by poor runoff in patients undergoing surgical procedures. The presence of poor runoff, external iliac artery disease, and female gender are independent predictors of poor outcome after iliac stenting, and therefore these risk factors should determine the need for surgical reconstruction.