title: Proximal extracranial vertebral artery disease in the New England Medical Center Posterior Circulation Registry.
abstract: OBJECTIVE
  To describe the clinical features of patients with occlusive disease of the proximal (V1) segment of the vertebral artery.
  
  
  METHODS
  Patients with either occlusion or high-grade stenosis involving the V1 segment were chosen for study from the New England Medical Center Posterior Circulation Registry. The registry is a consecutive series of patients with signs and symptoms of posterior circulation ischemia seen at the New England Medical Center, Boston, Mass, during a 10-year period. Clinical features, radiographic findings, and patient outcome were reviewed.
  
  
  RESULTS
  Of the 407 patients in the registry, 80 (20%) had V1 segment lesions. Patients could be classified into 5 groups: (1) V1 disease and coexistent severe intracranial occlusive disease of the posterior circulation (n=22); (2) V1 disease with evidence of artery-to-artery embolism (n=19); (3) suspected V1 disease with artery-to-artery embolism, but with other potential causes of stroke or less certain vascular diagnosis (n=20); (4) V1 disease associated with hemodynamic transient ischemic attacks (n=13); and (5) proximal vertebral arterial dissection (n=6). Hypertension, cigarette smoking, and coronary artery disease were common risk factors. Clinical features, location of infarct, and outcome differed between groups and reflected the presumed mechanisms of stroke.
  
  
  CONCLUSIONS
  Occlusive disease involving the V1 segment of the vertebral artery is common in patients with posterior circulation ischemia, but is often associated with other potential mechanisms of stroke. However, in a series of patients seen at a tertiary referral center, occlusive disease of the V1 segment was the primary mechanism of ischemia in 9% of patients.
authors.affiliation: Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Wityk
authors.forename: H M
authors.initials: HM
authors.lastname: Chang
authors.forename: A
authors.initials: A
authors.lastname: Rosengart
authors.forename: W C
authors.initials: WC
authors.lastname: Han
authors.forename: L D
authors.initials: LD
authors.lastname: DeWitt
authors.forename: M S
authors.initials: MS
authors.lastname: Pessin
authors.forename: L R
authors.initials: LR
authors.lastname: Caplan
mesh_terms: D000046:Academic Medical Centers; D000368:Aged; D001157:Arterial Occlusive Diseases / Q000503:physiopathology*; D003251:Constriction, Pathologic; D003327:Coronary Disease / Q000503:physiopathology; D003925:Diabetic Angiopathies / Q000503:physiopathology; D004617:Embolism / Q000503:physiopathology; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D002546:Ischemic Attack, Transient / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009511:New England; D012042:Registries; D012307:Risk Factors; D014715:Vertebrobasilar Insufficiency / Q000503:physiopathology*