Anatomic and clinical predictors of reintervention after subclavian artery stenting

Objective This study was conducted to determine long-term predictors of target lesion reintervention (TLR) after subclavian artery stenting (SAS). Methods This was a single-center retrospective review of patients with symptomatic atherosclerotic subclavian artery disease who underwent SAS between January 1999 and December 2013. Repeat intervention was only performed in patients with recurrent symptoms and ≥70% in-stent restenosis (ISR). TLR was defined as need for a repeat percutaneous intervention involving a previously stented area. Freedom from events (ISR and TLR) was analyzed using Kaplan-Meier curves. Cox regression analysis was used to determine the significant predictors of TLR and ISR. Results Index procedures were performed on 139 arteries in 138 patients (69.6% female). Patients were an average age of 64.5 years, with major comorbidities of hypertension (80.4%), hyperlipidemia (72.5%), and tobacco use (60.1%). Also performed during the study period were 24 TLR procedures, resulting 166 SAS interventions attempted for patients with subclavian atherosclerotic disease during a 15-year span. Of 166 procedures, 163 (98.2%) were treated successfully. Stents were placed in all but two index arteries. The main indications for SAS were subclavian steal syndrome (48.9%), arm claudication (21.6%), and coronary steal syndrome (28.8%). The average preprocedure stenosis was 87.2% ± 11.2%. For index procedures (139 arteries), duplex follow-up was available for 134 arteries (96.4%), with an overall ISR rate of 18.7% (25 of 134). Primary patency for the index procedures was 84.7% at 10 years. The overall TLR rate for the index procedures was 12.7% (17 cases). Seven patients required more than one secondary procedure. For all cases, the freedom from ISR was 91%, 77%, and 68% at 1, 5, and 10 years, respectively, and freedom from TLR was 94%, 85%, and 82% at 1, 5, and 10 years, respectively. Multivariate analysis showed the significant predictors of ISR were smoking/chronic obstructive pulmonary disease (hazard ratio [HR], 3.2; P =.001), age by decade (HR, 0.5; P <.001), discharged with statin therapy (HR, 0.3; P =.001), vessel diameter ≤7 mm (HR, 2.3; P =.028), and right-sided intervention (HR, 0.3; P =.040). The sole significant predictor of TLR was age by decade (HR, 0.6; P =.008). Conclusions SAS has a high primary success and durability with satisfactory outcomes well beyond 10 years. ISR was more likely to develop in patients who were smokers with chronic obstructive disease or had a baseline vessel size of ≤7 mm. Younger age could be an independent risk factor for secondary intervention.