The Study Of Treatment Of Intracranial Atheros-clerotic Stenosis With The Wingspan Stent

Ischemic cerebrovascular disease ma inly resulting from intracra nialatherosclerotic stenosis gradua lly becomes one of the prima ry causes of huma ndeath. The incidence rate of ischemic stroke in Chinese patients withsymptomatic intracra nial atherosclerotic stenosis is approxima tely 33.3% andranges from 8% to 22% in western. Despite ma ximum med ical therapy such asaspirin and warfarin, about 10% of patients with symptomatic intracra nialatherosclerotic stenosis will develop ischemic stroke, and the odds even reachesabout 60.7% especia lly in those with severe stenosis 10. In recent years,endovascular techniques develop expeditiously, and endovascular intervention isbecoming a commonly accepted form of treatment in patients with intracra nialatherosclerotic stenosis.The Wingspa n stent system (Boston Scientific Corp) is the first selfexpandablestent system designed for treatment of intracra nial atherosclerotic stenosis. Its approval was granted in April 2007 in China. The self-expandingnature of the Wingspa n stent provides several unique advantages in comparisonwith the balloon expandable stents. The deployed stent exerts a continuousoutward radia l force on the vessel wall. This outward radia l force prevents earlyvessel recoil, thus consolida ting the gains achieved with the initial angioplasty.Although the periprocedural complication and mortality of the system wereapproved acceptable in multi-center research , relatively high rates of in-stentrestenosis (ISR) have been observed in follow-up. The Gateway balloon is usedto predila te the target lesion before Wingspa n stenting. The balloon dia meter wassized to 80% of the "normal" parent vessel dia meter according to its Manual ofOperations. It is the choice of the undersized Gateway balloon to make safety ofthe Gateway balloon-Wingspan stent system possible, whereas it is the choice tomake its ISR rates relatively high.Therefore, our center tried to use norma l-sized Gateway balloon andWingspa n stent in treatment of symptomatic intracra nial atherosclerotic stenosis.The purpose of this study was to assess the safety and performa nce of thenorma l-sized Gateway balloon angioplasty and Wingspa n stenting in thetreatment of intracra nial atherosclerotic stenosis.The content and method are as follows: All patients had symptomatic strokewith severe intracra nial angiostenosis confirmed by angiography (≥50 stenosis).They were randomly divided into two groups: the undersized Gateway balloongroup (U group, the balloon dia meter was sized to 80% of the normal dia meterof the parent vessel) and the norma l-sized balloon group (N group, the balloondia meter was sized to 90-100% of the normal dia meter). They had beenpretreated with aspirin (300 mg daily) and clopidogrel (75 mg daily) for at least three days. The common risk factors including hypertension, hyperlipidemia anddiabetes were pretreated to ma inta in a relatively stable state. Periopera tiveclinical condition, and TCD, CTA or angiographic follow-up results wererecorded and analyzed.The results are as follows: During a 29-month period, 72 patients with 77intracra nial stenoses were treated in the U group and N group. All patients weresuccessfully stented. Stenoses treatment involved the midd le cerebral artery,vertebro-basilar artery and internal carotid supraclinoid segment. The stenosiswas improved from 74.2±12.6% (pretreatment) to 23.8±12.3% (posttreatment)in the U group and 70.9±12.9% to 20.1±10.1% in the N group. Of the 77stenoses treated, there were seven (9.0%) major periprocedural neurologica lcomplications, none of which led to death. The rema ining stenosis was40.8±19.2% in the U group and 32.5±25.2% in the N group. In-stent restenosis(ISR) occurred at a rate of 33.3% in the U group and 22.0% in the N group. Theincidence of ISR showed a significa nt difference between the two groups (p＜0.05). The prior Neurolink stent group (SSYLVIA trial) showed postproceduralresid ual stenosis (19.7±15.7%), periprocedural neurologica l complications(20.3%) and ISR (24.1%). The prior Wingspa n stent group showedpostprocedural resid ual stenosis (31.9±13.6%), periprocedural neurologicalcomplications (9.0%) and ISR (31.2%).Conclusions: In our study, baseline clinica l characteristics of the wholepatients were similar to those of patients with intracra nial atheroscleroticstenosis in prior clinica l trials . The norma l-sized Gateway balloon angioplastyand Wingspa n stenting for intracra nial atherosclerotic stenosis appear to be safewithout high periopera tive complications and perform well with high rate of technical success, good postoperative insta nt ima ge and low rate of ISR.