Multicenter clinical trial of the NexStent coiled sheet stent in the treatment of extracranial carotid artery stenosis: Immediate results and late clinical outcomes

Object. Carotid angioplasty with stent placement has been proposed as an alternative method for revascularization of carotid artery (CA) stenosis. A novel stent with a coiled sheet design (NexStent; EndoTex Interventional Systems, Inc., Cupertino, CA) has been introduced because it provides improved flexibility over conventional tubular designs during navigation through tortuous arterial segments. The authors report the results of a multicenter study in which they evaluated the safety, feasibility, and effectiveness of this stent in the treatment of CA stenosis. Methods. Enrollment was limited to patients with 70% or more symptomatic or asymptomatic stenosis of the internal CA. The primary end point was a technically successful implantation procedure (delivery of the stent to the target site and retrieval of the delivery device) resulting in less than 30% residual stenosis on angiograms obtained immediately postprocedure and no death or ipsilateral stroke immediately after or within 30 days following the procedure. The secondary effectiveness end point was prevention of an ipsilateral stroke within 31 days to 1 year postprocedure. The tertiary effectiveness end point was less than 70% residual stenosis demonstrated on CA Doppler ultrasonography performed at 6 and 12 months. Forty-four patients (mean age 71 years, range 51-89 years; 30 patients were men and 18 [41%] had symptomatic stenotic lesions) were treated using 45 NexStents (two stents were placed in one patient). Residual stenosis on postprocedure angiograms was less than 30% in all patients. The 1-month primary end point was achieved in 41 patients (93%). The three major adverse events that occurred within 30 days were one death related to congestive heart failure and two ipsilateral strokes, one of which resulted in death. No ipsilateral stroke occurred between 1 and 12 months postprocedure among 35 patients who completed the follow-up evaluation. Asymptomatic recurrent stenosis was identified in one patient at 6 months postprocedure, requiring the performance of repeated angioplasty. Conclusions. Placement of the NexStent was feasible and resulted in the effective treatment of patients with CA stenosis, with promising long-term results.