title: Risk factors for in-stent restenosis after vertebral ostium stenting.
abstract: OBJECTIVE
  To determine whether vascular risk factors, underlying vessel diameter, and/or the type of stent affect restenosis rates for vertebral ostium stents.
  
  
  METHODS
  A single-center retrospective analysis was conducted of 44 patients (31 men; mean age 61 years, range 32-81) who underwent stenting of 48 ostial lesions in the vertebral arteries between 1999 and 2005. Only patients who underwent angiographic follow-up were included in the analysis. Cox regression analysis was utilized for risk factor association with binary restenosis (> or =50% versus <50%). Stent types and stent categories were compared for differences in binary restenosis rates and lumen gain at follow-up angiography.
  
  
  RESULTS
  Twenty-three (48%) of 48 lesions had > or =50% stenosis at a mean follow-up of 7.7 months. Cigarette smoking was associated with higher binary restenosis rates (p=0.025), while hypertension, diabetes, hyperlipidemia, history of neck radiation, and known coronary artery and/or peripheral vascular disease were not. Reduced binary restenosis rates and improved lumen gain were seen in cobalt chromium balloon-expandable stents compared to non-cobalt chromium stents (p=0.002 and p=0.002, respectively), stainless steel balloon-expandable stents (p=0.005 and p=0.005), and the S670 stent (p=0.069 and p=0.069). The size of stent used was not associated with risk of restenosis (p=0.756).
  
  
  CONCLUSIONS
  Cobalt chromium stents were associated with reduced restenosis, while smoking was associated with increased restenosis risk.
authors.affiliation: Department of Neurology, University of Minnesota, Minneapolis, Minnesota, USA. rataylor@umn.edu
authors.forename: Robert A
authors.initials: RA
authors.lastname: Taylor
authors.forename: Farhan
authors.initials: F
authors.lastname: Siddiq
authors.forename: M Fareed K
authors.initials: MF
authors.lastname: Suri
authors.forename: Coleman O
authors.initials: CO
authors.lastname: Martin
authors.forename: Minako
authors.initials: M
authors.lastname: Hayakawa
authors.forename: John C
authors.initials: JC
authors.lastname: Chaloupka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D001157:Arterial Occlusive Diseases / Q000628:therapy*; D002857:Chromium; D003035:Cobalt; D005260:Female; D006083:Graft Occlusion, Vascular / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D015607:Stents; D016896:Treatment Outcome; D014711:Vertebral Artery
chemical_list: D002857:Chromium; D003035:Cobalt