Complications and follow-up after unprotected carotid artery stenting.

PURPOSE: This prospective study was undertaken to determine the success rate, complications, and outcome of carotid artery stenting (CAS) without the use of cerebral protection devices. METHODS: During 12 months, 94 high-grade stenoses of the carotid artery in 91 consecutive patients were treated. Sixty-six (70%) of the stenoses were symptomatic and 28 (30%) were asymptomatic. RESULTS: In all 94 carotid stenoses CAS was successfully performed. During the procedure and within the 30 days afterwards, there were 2 deaths and 3 major strokes in the 66 symptomatic patients, resulting in a combined death and stroke rate of 5 of 66 (7%). Only one of these complications, a major stroke, occurred during the procedure. In the 6-month follow-up, one additional major stroke occurred in a originally symptomatic patient resulting in a combined death and stroke rate of 6 of 66 (10%) for symptomatic patients at 6 months. No major complications occurred in asymptomatic patients during the procedure or in the 6-month follow-up period. At 6 months angiographic follow-up the restenosis rate with a degree of >50% was 3 of 49 (6%) and the rate with a degree of >or=70% was 1 of 49 (2%). CONCLUSIONS: Cerebral embolization during CAS is not the only cause of the stroke and death rate associated with the procedure. The use of cerebral protection devices during the procedure may therefore not prevent all major complications following CAS.

Angioplasty or stenting of extra- and intracranial vertebral artery stenoses.

PURPOSE: To determine the feasibility and safety of angioplasty or angioplasty and stenting of extra- and intracranial vertebral artery (VA) stenosis. METHODS: In 16 consecutive patients (9 men, 7 women; mean age 61 years, range 49-74 years) 16 stenotic VAs were treated with angioplasty or angioplasty and stenting. Eleven stenoses were localized in V1 segment, 1 stenosis in V2 segment and 4 stenoses in V4 segment of VA. Fourteen VA stenoses were symptomatic, 2 asymptomatic. The etiology of the stenoses was atherosclerotic in all cases. RESULTS: Angioplasty was performed in 8 of 11 V1 and 2 of 4 V4 segments of the VA. In 3 of 11 V1 segments and 2 of 4 V4 segments of the VA we combined angioplasty with stenting. The procedures were successfully performed in 14 of 16 VAs (87%). Complications were asymptomatic vessel dissection resulting in vessel occlusion in 1 of 11 V1 segments and asymptomatic vessel dissection in 2 of 4 V4 segments of the VA. One patient died in the 24-hr period after the procedure because of subarachnoid hemorrhage as a complication following vessel perforation of the treated V4 segment. CONCLUSION: Angioplasty or angioplasty and stenting of extracranial VA stenoses can be performed with a high technical success rate and a low complication rate. In intracranial VA stenosis the procedure is technically feasible but complications can be life-threatening. The durability and procedural complication rates of primary stenting without using predilation in extra- and intracranial VA stenosis should be defined in the future.

Clinical results of carotid artery stenting with a nitinol self-expanding stent (SMART stent).

Our objective was to assess the technical feasibility and the clinical results of internal carotid artery (ICA) stenting using a nitinol self-expanding stent (SMART stent). In 13 patients 13 high-grade stenoses of the internal carotid artery were treated via an implantation of a SMART stent. In all cases a predilation of the stenosis and a postdilation within the stent were performed. Follow-up examinations were carried out in all patients after a period of 6 months. In each case the implantation of the stent was performed without technical complications. In 12 of 13 cases the stent was placed in the patients' internal carotid artery, in 1 case from the internal to the common carotid artery (CCA). The average degree of stenosis of 78% (70-95%) was reduced to an average of 2.8% (0-21%). The 6-month follow-up angiography showed an average degree of restenosis of 11.8% (0-29%) in 8 of 13 patients. Duplex sonography in the remaining 5 patients demonstrated patent stents. One patient showed brief neurological symptoms during the intervention. No further complications occurred during follow-up time. Treatment of internal carotid artery stenosis with the SMART stent seems technically feasible, safe, and promises long-term patency.

Cerebral ischemia detected with diffusion-weighted MR imaging after stent implantation in the carotid artery.

BACKGROUND AND PURPOSE: Concern regarding the safety of stent implantation in the carotid artery exists because of the risk of cerebral embolization during the procedure. The purpose of this prospective study was to determine the incidence of new areas of cerebral ischemia, as detected by using diffusion-weighted MR imaging after stent implantation in the carotid artery. METHODS: Diffusion-weighted MR imaging of the brain was performed in 67 patients with 70 high-grade stenoses of the carotid artery before and 24 hours after stent implantation. RESULTS: The neurologic status of the patients was unchanged after 69 of 70 procedures. During one procedure, symptomatic cerebral embolization occurred. Diffusion-weighted MR images showed new ipsilateral lesions after stent implantation in 20 patients (29%), including the symptomatic patient, and new contralateral lesions in six patients (9%). Fifty-two of 59 postprocedural lesions occurred in the vascular territory supplied by the treated vessel. The occurrence of new postprocedural ipsilateral lesions was not significantly correlated with patient demographic data, characteristics of the stenoses, or details of the procedure. CONCLUSION: In 29% of the procedures, stent implantation in the carotid artery was associated with new areas of cerebral ischemia, as detected by using diffusion-weighted MR images; these findings indicated the occurrence of cerebral microemboli during such procedures. In all patients except one, the new lesions were clinically silent.