Open- versus closed-cell stents in transfemoral carotid artery stenting for carotid bifurcation disease: a target trial emulation.

Abstract

The comparative association of open-cell stent (OCS) and closed-cell stent (CCS) design with outcomes after protected transfemoral carotid artery stenting, particularly long-term patency, remains uncertain. This study compared OCS and CCSs in patients with carotid bifurcation disease. We retrospectively emulated a target trial using data from three centers. Consecutive patients who underwent transfemoral carotid artery stenting with embolic protection devices for atherosclerotic carotid bifurcation lesions were included and classified according to stent design. Stabilized inverse probability of treatment weighting was used to balance baseline covariates. Periprocedural outcomes were assessed within 30 days. Follow-up outcomes included in-stent restenosis (ISR), severe ISR, symptomatic ISR, recurrent ipsilateral ischemic events (stroke or transient ischemic attack), and target-vessel revascularization. Among 1024 patients, 524 (51.2%) were symptomatic and 500 (48.8%) were asymptomatic; 577 received OCSs and 447 received CCSs. Median follow-up was 26.0 months (interquartile range, 19.4-32.4 months). After inverse probability of treatment weighting, baseline covariates were well balanced. Periprocedural adverse events did not differ significantly between groups. During follow-up, CCS use was associated with higher risks of ISR (hazard ratio [HR], 1.66; 95% confidence interval [CI], 1.19-2.31; P = .003), severe ISR (HR, 1.61; 95% CI, 1.06-2.45; P = .026), symptomatic ISR (HR, 2.03; 95% CI, 1.20-3.45; P = .008), and recurrent transient ischemic attack (HR, 3.06; 95% CI, 1.24-7.55; P = .015). Any ISR and severe ISR were strongly associated with recurrent ipsilateral ischemic events (both P < .001). CCS use appeared more strongly associated with ISR in symptomatic patients, without significant interaction by symptom status (P for interaction = .206). Sensitivity analyses were concordant with the primary results. OCSs were associated with a lower hazard of restenosis and no material difference in periprocedural outcomes compared with CCSs. These findings support preferential consideration of OCSs at the carotid bifurcation for long-term patency, whereas CCSs may retain a theoretical advantage in unstable plaques requiring denser plaque coverage.