Do device characteristics impact outcome in carotid artery stenting?

Objectives: The study was conducted to identify patient and procedural parameters that negatively impact the 30-day rates for stroke, death and transient ischemic attack (TIA) after carotid artery stenting (CAS) and that might be modified or further studied in future efforts to improve CAS. Methods: This was a retrospective investigation of a dual-center CAS database of 701 consecutive CAS patients (414 men; mean age, 72.4 +/- 8.4). A subset of patient-related, lesion-related, or procedure-related variables (age >= 80, left sided lesion, symptomatic, nicotine abuse, hypertension, diabetes mellitus, other peripheral vascular disease, hypercholesterolemia, embolic protection devices usage, predilation, ulcerated lesion, echolucent plaque, restenosis after surgery) were analyzed for association with occurrence of stroke, death, or TIA <= 30 days after CAS. The odds ratio (OR) and 95% confidence interval (CI) and P value were calculated for each variable to predict adverse outcome. Results: The overall combined rate of stroke, death, and TIA within this database was 3.7% at 30 days. In the total population of 701 patients, only the OR of 2.7 for hypercholesterolemia (95% CI, 1.0 to 7.3; P = .041) was found to be significant. Subgroup analysis of the 304 symptomatic patients (43%) showed that open-cell stent designs and concentric EPD designs yielded an OR of 4.1 (95% CI, 1.4 to 12, P = .0136) and 3.3 (95% CI, 1.016 to 10, P = .0525), respectively, for 30-day stroke/death/TIA within this database. Analysis of open-cell stent designs and concentric EPD designs in patients with echolucent lesions yielded an OR of 3.1 (95% CI, 1.2 to 8.2, P = .0343) and 3.7 (95% CI, 1.3 to 10, P = .0174), respectively, for 30-day stroke/death/TIA. Conclusions: We conclude that increased analysis of device design variables may be necessary. Particularly in symptomatic patients or with echolucent lesions, closed-cell design and eccentric filters seem superior. Prospective investigation comparing open-cell vs closed-cell stents and eccentric vs concentric filter devices may be warranted.