Carotid artery stenting with open vs closed stent cell configurations in the CREST-2 Registry

Objective: Intraprocedural atheroembolization during carotid artery stenting (CAS) can be reduced through careful patient selection, consideration of vascular anatomy and lesion characteristics, operator and institutional experience, peri-procedural antithrombotic and antiplatelet therapy, and use of embolic protection. However, CAS can also result in stroke as the stent is deployed and embolic protection withdrawn. The free-cell area of most closed-cell stents is <5 mm², and ≥5 mm² for open-cell stents. The larger area may permit escape of more atheromatous debris. Comparisons of clinical outcomes between closed-cell and open-cell stents have been inconclusive. The aim of this study is to compare clinical outcomes associated with CAS using open-cell vs closed-cell stents. Methods: The CREST-2-Registry (C2R) enrolls asymptomatic and symptomatic patients for whom CAS is favored because of high risk for surgery or patient preference. C2R implements operator- and site-credentialing, careful lesion selection, and standardized procedural protocols. Patient characteristics, procedural details, and outcomes are recorded. Interventionists may use United States Food and Drug Administration-approved devices including open-cell stents (Rx Acculink [Abbott Vascular], Precise Pro Rx [Cordis-Cardinal Health], and Protégé Rx [Medtronic/Covidien]), or closed-cell stents (XACT [Abbott Vascular] and Wallstent Monorail Endoprosthesis [Boston Scientific]). Multivariable logistic regression was used to assess relate stent cell configuration to peri-procedural (30-day) stroke or death (SD). Results: Of 5307 procedures performed by 163 interventionists across 101 clinical centers, 2054 (38.7%) received open-cell stents, and 3253 (61.3%) received closed-cell stents. In the periprocedural period, 91 patients (1.7%) experienced a stroke (3 were fatal), and 16 patients died without experiencing strokes (0.4%). After adjusting for age, sex, symptomatic status, and case urgency, and for effect-modification by indication, periprocedural SD was significantly higher when an open-cell stent was placed in a primary lesion compared with closed-cell stents (3.5 events per 100 procedures using open-cell stents [95% confidence interval [CI], 2.6-4.7] vs 2.2% [95% CI, 1.6-3.0] using closed-cell stents (odds ratio, 1.59; 95% CI, 1.13-2.23; P <.01). Periprocedural SD was not significantly different between stent types when placed in a restenotic lesion (1.2% [95% CI, 0.4-3.3]) using open-cell stents vs 4.0% (95% CI, 2.2-7.2) using closed-cell stents (odds ratio, 0.31; 95% CI, 0.09-1.01; P =.052). Conclusions: Stent design influences periprocedural stroke or death in carotid stenting. Closed-cell stents are associated with a lower event rate when treating primary atherosclerosis, but not in the setting of restenosis.