Society for Vascular Surgery Vascular Registry evaluation of stent cell design on carotid artery stenting outcomes

Abstract

The Society for Vascular Surgery (SVS) Vascular Registry (VR) collects data on outcomes of carotid endarterectomy and carotid artery stenting (CAS). The purpose of this study was to evaluate the impact of open vs closed cell stent design on the in-hospital and 30-day outcome of CAS. The VR collects provider-reported data on patients using a Web-based database. Data were analyzed both in-hospital and at 30 days postprocedure. The primary outcome is combined death/stroke/myocardial infarction (MI). As of October 14, 2009, there were 4337 CAS with discharge data and 2397 with 30-day data. Open cell stents (OPEN) were used in 3451 patients (79.6%), and closed cell stents (CLOSED) were used in 866 patients (20.4%). Baseline demographics showed no differences in age, gender, race, and ethnicity. However, the OPEN group had more patients with atherosclerosis (74.5% vs 67.4%; P = .0003) as the etiology of carotid artery disease. The OPEN group also had a higher prevalence of preprocedural stroke (25.8% vs 21.4%; P = .0079), chronic obstructive pulmonary disease (COPD; 21.0% vs 17.6%; P = .0277), cardiac arrhythmia (14.7% vs 11.4%; P = .0108), valvular heart disease (7.4% vs 3.7%; P < .0001), peripheral vascular disease (PVD; 40.0% vs 35.3%; P = .0109), and smoking history (59.0% vs 54.1%; P = .0085). There are no statistically significant differences in the in-hospital or 30-day outcomes between the OPEN and CLOSED patients. Further subgroup analyses demonstrated symptomatic patients had a higher event rate than the asymptomatic cohort in both the OPEN and CLOSED groups. Among symptomatic patients, the OPEN patients had a lower (0.43% vs 1.41%; P = .0349) rate of in-hospital mortality with no difference in stroke or transient ischemic attack (TIA). There were no differences in 30-day event rates. In asymptomatic patients, there were also no statistically significant differences between the OPEN and CLOSED groups. After risk adjustment, there remained no statistically significant differences between groups of the primary endpoint (death/stroke/MI) during in-hospital or 30 days. In-hospital and 30-day outcomes after CAS were not significantly influenced by stent cell design. Symptomatic patients had higher adverse event rates compared to the asymptomatic cohort. As there is no current evidence of differential outcome between the use of open and closed cell stents, physicians should continue to use approved stent platforms based on criteria other than stent cell design.