Clinical And Imaging Follow-up Study On Endovascular Stenting Of Extracranial Vertebral Artery Stenosis

Background:Endovascular angioplasty and stenting is now widely used for the treatment of extracranial vertebral artery stenosis.Although the procedure is safe enough,its efficacy of preventing the recurrence of posterior circulation ischemia has not been proved to be superior to that of conservative therapy.Some authors also reported that the in-stent restenosis rate of extracranial vertebral artery stenting was relatively high,and its risk factors was unclear yet.Purpose:To investigate posterior circulation ischemia recurrence rate,in-stent restenosis rate,as well as potential risk factors of restenosis for patients who underwent extracranial vertebral artery stenting.Methods:From the prospective Neurointervention Registry in Neurosurgical Department,Beijing hospital,Electronic Medical Records and PACS imaging System,we retrieved clinical and imaging data for patients who received extracranial vertebral artery stenting between Jan 2014 and Jun 2017.We retrospectively reviewed and analyzed their demographic characteristics,risk factors,of cerebrovascular diseases,clinical presentations,angiographic features,endovascular intervention results,clinic visit and telephone questionnaire follow up results,as well as ultrasound,CTA and DSA follow up results.Kaplan-Meier survive analysis was used to estimate risk of recurrence of posterior circulation ischemia.Uni-variate and multi-variant regression analysis were used to determine potential risk factors of in-stent restenosis.Results:A total of 115 consecutively patients(1241esions)were included.All of the extracranial vertebral artery stenting procedures was technical successful.No peri-procedural complications occurred.During clinical follow up for 35.7±12.3 months,posterior circulation ischemia recurred in 12(10.4%)patients,of which 2 strokes and 10 TIAs occurred.One(0.9%)patient died due to the recurrence of posterior circulation stroke.The 3-year posterior circulation ischemia free survive rate was 89.6%.During imaging follow up for 33.8±13.1 months of 112 stents(103 patients),in-stent restenosis occurred in 22 lesions(19.6%),of which 4 lesions(3.6%)received repeat endovascular therapy.Regression analysis showed that diabetes mellitus and relatively smaller diameter of stents were independent predictors of in-stent restenosis(P<0.05).Conclusion:Extracranial vertebral artery stenting is effective in preventing reoccurrence of posterior circulation ischemia.The rate of in-stent restenosis is relatively high.Patients with diabetes and smaller diameters of vertebral artery stent are more prone to restenosis.