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

Abstract

Background: Intra-procedural 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 However, CAS can also result in stroke as the stent is deployed and embolic protection withdrawn.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.

Objective: The aim of this study is to compare clinical outcomes associated with CAS using open-cell versus 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 FDA-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 5,307 procedures performed by 163 interventionists across 101 clinical centers, 2,054 (38.7%) received open-cell stents, and 3,253 (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 stroke-or-death (SD) was significantly higher when an open-cell stent was placed in a primary lesion compared to closed-cell stents (3.5 events per 100 procedures using open-cell stents [95% CI 2.6, 4.7] vs 2.2% [1.6, 3.0] using closed-cell stents, Odds Ratio 1.59 [1.13, 2.23], p<0.01). Periprocedural SD was not significantly different between stent types when placed in a restenotic lesion (1.2% [0.4, 3.3] using open-cell stents vs 4.0% [2.2, 7.2] using closed-cell stents, OR 0.31 [0.09, 1.01], p=0.052).

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.