Outcome of carotid artery stenting at 2 years follow-up: comparison of nitinol open cell versus stainless steel closed cell stent design.

The aim of this study was to compare the clinical and ultrasound outcome of carotid artery stenting at 2-year follow-up in patients treated with open-cell nitinol stents versus patients treated with closed cell stainless steel stents.This was a non-randomized, retrospective study including 123 patients in whom 132 carotid stent-procedures were performed. Nine patients were treated bilaterally. All patients presented with severe asymptomatic (80%) or symptomatic (>70%) carotid artery stenosis and were treated by carotid angioplasty and stent placement with or without filter embolic protection system. Follow-up consisted of physical evaluation at 1, 6, 12 and 24 months and assessment of the stent patency by ultrasound examination at 6, 12 and 24 months after the stent procedure.In 72 procedures a closed cell stainless steel stent was implanted, in the remaining 60 procedures an open cell nitinol stent was placed. In 8 patients with a stainless steel stent (11%) and in 6 patients with a nitinol stent (10%) a stroke occurred during the follow-up period (P=0.79). Ultrasound examination revealed an in-stent restenosis of 50% to 80% in the stainless steel group (N.=9, 15%) and in the nitinol group (N.=10, 17%) (P=0.7).At 2-year follow-up after carotid artery stenting, there is no difference in clinical outcome or in stent patency among patients treated with open versus closed cell design stents. Subsequently the type of carotid stent design does not seem to impact the overall midterm outcome after carotid artery stenting.