Effect of Open- vs Closed-Cell Stent Design on Periprocedural Outcomes and Restenosis After Carotid Artery Stenting: A Systematic Review and Comprehensive Meta-analysis

Purpose:To compare periprocedural complications and in-stent restenosis rates associated with open- vs closed-cell stent designs used in carotid artery stenting (CAS). Methods: A systematic search was conducted to identify all randomized and observational studies published in English up to October 31, 2017, that compared open- vs closed-cell stent designs in CAS. Identified studies were included if they reported the following outcomes: stroke, transient ischemic attack (TIA), myocardial infarction (MI), hemodynamic depression, new ischemic lesions detected on imaging, and death within 30 days, as well as the incidence of in-stent restenosis. A random-effects model meta-analysis was employed. Model results are reported as the odds ratio (OR) and 95% confidence interval (CI). The I-2 statistic was used to assess heterogeneity. Results: Thirty-three studies (2 randomized trials) comprising 20,291 patients (mean age 71.3 +/- 3.0 years; 74.6% men) were included. Patients in the open-cell stent group had a statistically significant lower risk of restenosis >= 40% (OR 0.42, 95% CI 0.19 to 0.92; I-2=0%) and >= 70% (OR 0.23, 95% CI 0.10 to 0.52; I-2=0%) at a mean follow-up of 24 months. No statistically significant differences were identified for periprocedural stroke, TIA, new ischemic lesions, MI, hemodynamic depression, or death within 30 days after CAS. Sensitivity analysis of the 2 randomized controlled trials only did not point to any significant differences either. Conclusion: Use of open-cell stent design in CAS is associated with a decreased risk for restenosis when compared to the closed-cell stent, without significant differences in periprocedural outcomes.