title: Impact of vertebral artery disease on dynamic cerebral autoregulation.
abstract: OBJECTIVE
  This study applied dynamic cerebral autoregulation (DCA) testing distally to severe bilateral vertebral artery disease (BVAD).
  
  
  METHODS
  Using continuous monitoring of beat-to-beat blood pressure and transcranial Doppler of the posterior cerebral arteries (PCA) were examined in 20 patients with BVAD and 22 controls. DCA testing was based on the 'high-pass filter model', which predicts a positive phase relationship between spontaneous oscillations (M-waves 3-9 cpm and R-waves 9-20 cpm) in blood pressure and cerebral blood flow velocity.
  
  
  RESULTS
  In patients with BVAD, DCA testing detected autoregulatory deficits of different degrees. The lowest M-wave phase shift angles were found in the PCA territory distally to intracranial BVAD.
  
  
  CONCLUSIONS
  This study suggests that DCA testing of the PCA could help to quantify the hemodynamic impact of BVAD. It highlights the relevance of functional TCD sonography as a useful diagnostic tool for the hemodynamic evaluation of vertebrobasilar disease.
authors.affiliation: Department of Neurology, University Hospital Aachen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Haubrich
authors.forename: A
authors.initials: A
authors.lastname: Kohnke
authors.forename: R R
authors.initials: RR
authors.lastname: Diehl
authors.forename: W
authors.initials: W
authors.lastname: Möller-Hartmann
authors.forename: C
authors.initials: C
authors.lastname: Klötzsch
mesh_terms: D000368:Aged; D001143:Arousal / Q000502:physiology; D001288:Attention / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D001921:Brain / Q000098:blood supply* / Q000503:physiopathology; D005260:Female; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation; D020769:Posterior Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D017585:Ultrasonography, Doppler, Transcranial; D014715:Vertebrobasilar Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology