Cerebral autoregulation is preserved in multiple system atrophy: A transcranial Doppler study.
Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA.
Pavy-Le Traon
Anne
A
Laboratory of Autonomic Nervous System and Neurosonology, Vascular Neurology Department, Hopital Rangueil, Toulouse, France. pavy.a@chu-toulouse.fr
Hughson
Richard L
RL
Thalamas
Claire
C
Galitsky
Monique
M
Fabre
Nelly
N
Rascol
Olivier
O
Senard
Jean-Michel
JM
D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D019578:Multiple System Atrophy / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D017711:Nonlinear Dynamics; D013057:Spectrum Analysis; D016683:Supine Position / Q000502:physiology; D017585:Ultrasonography, Doppler, Transcranial