Document Detail


Transcranial Doppler monitoring in Parkinson's disease: cerebrovascular compensation of orthostatic hypotension.
MedLine Citation:
PMID:  20800957     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Despite of precipitous blood pressure falls in Parkinson's Disease (PD) patients, they may not experience syncope or postural complaints. Can cerebral blood flow regulation explain why orthostatic hypotension (OH) has often no accompanying symptoms? In patients with PD and OH (18 asymptomatic; 8 symptomatic), arterial blood pressure (ABP) as well as Doppler-detected cerebral blood flow velocity (CBFV) in middle and posterior cerebral arteries (MCA and PCA) were monitored during head-up tilt and compared with 25 controls and eight non-PD-OH patients. Analysis included the transfer function between slow spontaneous pressure and flow-oscillations. ABP and CBFV were maintained at significantly higher levels in asymptomatic than symptomatic PD-OH (ABP: 85.7 ± 10.5 vs. 66.9 ± 12.5%; MCA-FV: 83.3 ± 9.3 vs. 66.1 ± 6.8%; PCA-FV: 84.4 ± 12.2 vs. 65.9 ± 9.3% of supine). When orthostatic complaints occurred, CBFV depended directly on ABP changes (MCA r(2) = 0.64; PCA r(2) = 0.62; both p < 0.05). Despite of a tilt-induced blood pressure instability in PD-OH, the transfer function parameters did not differ from normal [phase: MCA: 46.6 ± 20.5°; PCA 39.2 ± 28.8°, gain: MCA 2.0 ± 0.7; PCA 2.9 ± 1.6)]. Results showed a normal autoregulatory response to downward blood pressure shifts in PD. Moreover, orthostatic blood pressure instability is compensated equally sufficient in anterior and posterior parts of cerebral circulation. Whether in PD patients, OH becomes symptomatic rather seems to depend on blood pressure falling below the autoregulated range.
Authors:
Christina Haubrich; Katrin Pies; Manuel Dafotakis; Frank Block; Christof Kloetzsch; Rolf R Diehl
Related Documents :
1942277 - Interpretation and quantification of penile blood flow studies using duplex ultrasonogr...
836357 - Inverse effect of chronically elevated blood flow on atherogenesis in miniature swine.
3196067 - Transient hyperoxia and cerebral blood flow velocity in infants born prematurely and at...
18380577 - Relationships between velocities of pulmonary venous flow and plasma concentrations of ...
17057567 - The role of computerized tomography-myelography in a patient with spontaneous intracran...
3343867 - Effect of blood conservation efforts in cardiac operations at the mayo clinic.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Ultrasound in medicine & biology     Volume:  36     ISSN:  1879-291X     ISO Abbreviation:  Ultrasound Med Biol     Publication Date:  2010 Oct 
Date Detail:
Created Date:  2010-09-20     Completed Date:  2011-01-20     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0410553     Medline TA:  Ultrasound Med Biol     Country:  England    
Other Details:
Languages:  eng     Pagination:  1581-7     Citation Subset:  IM    
Copyright Information:
Copyright © 2010 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Affiliation:
Department of Neurology, University Hospital Aachen, Aachen, Germany. Christina.Haubrich@t-online.de
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aged
Blood Flow Velocity
Blood Pressure
Cerebrovascular Circulation*
Female
Humans
Hypotension, Orthostatic / etiology,  physiopathology*,  ultrasonography*
Male
Middle Cerebral Artery / ultrasonography
Parkinson Disease / complications,  physiopathology*,  ultrasonography*
Posterior Cerebral Artery / ultrasonography
Ultrasonography, Doppler, Transcranial / methods*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Evaluation of coronary flow velocity reserve in homozygous familial hypercholesterolemia by transtho...
Next Document:  Liver metastases: Sulphur hexafluoride-enhanced ultrasonography for lesion detection: a systematic r...