Does free cell area influence the outcome in carotid artery stenting?

Objectives. To identify if carotid stent design, especially free cell area, impacts on the 30-day rates for stroke, death and TIA after carotid artery stenting (CAS). Material and methods. A CAS database of 3179 consecutive CAS patients was retrospectively assessed. The distribution Of neurological complications were analysed for association with the different stent types and designs. Events where subdivided into procedural and postprocedural events. Results. The overall combined rate of TIA, stroke and death was 2.8% at 30 days (late events 1.9%). The post-procedural event rate analyzed for differences stents varied from 1.2% using BSCI Carotid Wallstent to 5.9% using Medtronic Exponent. The late event rates varied from 1.2% to 3.4% for free cell areas < 2.5 mm(2) and > 7.5 mm(2) respectively (p < 0.05). Post-procedural event rate was 1.3% for closed cells and 3.4% for open cells. All these differences were highly pronounced among symptomatic patients (p < 0.0001). Conclusions. After carotid stenting, complication rates vary according to stent type, free cell area and cell design. In the symptomatic population (and also in the total population), post-procedural complication rates are highest for the open cell types and increase with larger free cell area.