From the Autonomic Disorders Center, Department of Neurology, Mayo Clinic
and Foundation, Rochester, Minn.
Correspondence to Phillip A. Low, MD, Autonomic Disorders Center, Department of Neurology, Mayo Clinic and Foundation, 200 First St SW, Rochester, MN 55905. E-mail low.phillip{at}mayo.edu
Background and Purpose—We sought to
evaluate cerebral autoregulation in patients with
orthostatic hypotension (OH).
Methods—We studied 21 patients (aged 52 to 78 years) with
neurogenic OH during 80° head-up tilt. Blood flow velocities (BFV)
from the middle cerebral artery were continuously monitored with
transcranial Doppler sonography, as were heart rate,
blood pressure (BP), cardiac output, stroke volume, CO2,
total peripheral resistance, and cerebrovascular
resistance.
Results—All OH patients had lower BP (P<.0001),
BFV_diastolic (P<.05), CVR
(P<.007), and TPR (P<.02) during
head-up tilt than control subjects. In control subjects, no
correlations between BFV and BP were found during head-up tilt,
suggesting normal autoregulation. OH patients could be separated into
those with normal or expanded autoregulation (OH_NA; n=16) and those
with autoregulatory failure (OH_AF; n=5). The OH_NA group showed either
no correlation between BFV and BP (n=8) or had a positive BFV/BP
correlation (R2>.75) but with a flat slope.
An expansion of the "autoregulated" range was seen in some
patients. The OH_AF group was characterized by a profound fall in BFV
in response to a small reduction in BP (mean
Conclusions—The most common patterns of cerebral response to OH
are autoregulatory failure with a flat flow-pressure relationship or
intact autoregulation with an expanded autoregulated range. The least
common pattern is autoregulatory failure with a steep flow-pressure
relationship. Patients with patterns 1 and 2 have an enhanced capacity
to cope with OH, while those with pattern 3 have reduced capacity.
© 1998 American Heart Association, Inc.
Original Contributions
Autoregulation of Cerebral Blood Flow in Orthostatic Hypotension
BP <40 mm Hg;
R2>.75).
Key Words: autoregulation • cerebral blood flow • hypotension, orthostatic • ultrasonics
This article has been cited by other articles:
 |
|
 |
|
  D Gupta and M D Nair Neurogenic orthostatic hypotension: chasing "the fall" Postgrad. Med. J., January 1, 2008; 84(987): 6 - 14. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B.M.T. Deegan, M. O'Connor, T. Donnelly, S. Carew, A. Costelloe, T. Sheehy, G. OLaighin, and D. Lyons Orthostatic hypotension: a new classification system Europace, October 1, 2007; 9(10): 937 - 941. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. A. Rickards, K. L. Ryan, W. H. Cooke, K. G. Lurie, and V. A. Convertino Inspiratory resistance delays the reporting of symptoms with central hypovolemia: association with cerebral blood flow Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2007; 293(1): R243 - R250. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K.-i. Iwasaki, B. D. Levine, R. Zhang, J. H. Zuckerman, J. A. Pawelczyk, A. Diedrich, A. C. Ertl, J. F. Cox, W. H. Cooke, C. A. Giller, et al. Human cerebral autoregulation before, during and after spaceflight J. Physiol., March 15, 2007; 579(3): 799 - 810. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Lavi, D. Gaitini, V. Milloul, and G. Jacob Impaired cerebral CO2 vasoreactivity: association with endothelial dysfunction Am J Physiol Heart Circ Physiol, October 1, 2006; 291(4): H1856 - H1861. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. H. Gibbons and R. Freeman Delayed orthostatic hypotension: A frequent cause of orthostatic intolerance. Neurology, July 11, 2006; 67(1): 28 - 32. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Guo, N. Tierney, F. Schaller, P. B. Raven, S. A. Smith, and X. Shi Cerebral autoregulation is preserved during orthostatic stress superimposed with systemic hypotension J Appl Physiol, June 1, 2006; 100(6): 1785 - 1792. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Singer, P. Sandroni, T. L. Opfer-Gehrking, G. A. Suarez, C. M. Klein, S. Hines, P. C. O'Brien, J. Slezak, and P. A. Low Pyridostigmine Treatment Trial in Neurogenic Orthostatic Hypotension Arch Neurol, April 1, 2006; 63(4): 513 - 518. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. S. Olufsen, J. T. Ottesen, H. T. Tran, L. M. Ellwein, L. A. Lipsitz, and V. Novak Blood pressure and blood flow variation during postural change from sitting to standing: model development and validation J Appl Physiol, October 1, 2005; 99(4): 1523 - 1537. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J C Chambers Should we screen hospice inpatients for orthostatic hypotension? Palliative Medicine, June 1, 2005; 19(4): 314 - 318. [Abstract] [PDF]
|
|
|
|
 |
|
 H.-K. Kuo, F. Sorond, I. Iloputaife, M. Gagnon, W. Milberg, and L. A. Lipsitz Effect of Blood Pressure on Cognitive Functions in Elderly Persons J. Gerontol. A Biol. Sci. Med. Sci., November 1, 2004; 59(11): 1191 - 1194. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Lavi, R. Egbarya, R. Lavi, and G. Jacob Role of Nitric Oxide in the Regulation of Cerebral Blood Flow in Humans: Chemoregulation Versus Mechanoregulation Circulation, April 15, 2003; 107(14): 1901 - 1905. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. R. Edwards, J. K. Shoemaker, and R. L. Hughson Dynamic modulation of cerebrovascular resistance as an index of autoregulation under tilt and controlled PETCO2 Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2002; 283(3): R653 - R662. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Schondorf, R. Stein, R. Roberts, J. Benoit, and W. Cupples Dynamic cerebral autoregulation is preserved in neurally mediated syncope J Appl Physiol, December 1, 2001; 91(6): 2493 - 2502. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Serrador, S. J. Wood, P. A. Picot, F. Stein, M. S. Kassam, R. L. Bondar, A. H. Rupert, and T. T. Schlegel Effect of acute exposure to hypergravity (GX vs. GZ) on dynamic cerebral autoregulation J Appl Physiol, November 1, 2001; 91(5): 1986 - 1994. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Houtman, J. M. Serrador, W. N. J. M. Colier, D. W. Strijbos, K. Shoemaker, and M. T. E. Hopman Changes in cerebral oxygenation and blood flow during LBNP in spinal cord-injured individuals J Appl Physiol, November 1, 2001; 91(5): 2199 - 2204. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. K. Shoemaker, D. D. O'Leary, and R. L. Hughson PETCO2 inversely affects MSNA response to orthostatic stress Am J Physiol Heart Circ Physiol, September 1, 2001; 281(3): H1040 - H1046. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Ouchi, H. Okada, E. Yoshikawa, M. Futatsubashi, and S. Nobezawa Absolute Changes in Regional Cerebral Blood Flow in Association with Upright Posture in Humans: An Orthostatic PET Study J. Nucl. Med., May 1, 2001; 42(5): 707 - 712. [Abstract] [Full Text]
|
|
|
|
|
|
T. Kawaguchi, O. Uyama, M. Konishi, T. Nishiyama, and T. Iida Orthostatic Hypotension in Elderly Persons During Passive Standing: A Comparison With Young Persons J. Gerontol. A Biol. Sci. Med. Sci., May 1, 2001; 56(5): 273M - 280. [Abstract] [Full Text]
|
|
|
|
 |
|
 M.P.M. Harms, W.N.J.M. Colier, W. Wieling, J.W.M. Lenders, N.H. Secher, and J.J. van Lieshout Orthostatic Tolerance, Cerebral Oxygenation, and Blood Velocity in Humans With Sympathetic Failure Stroke, July 1, 2000; 31(7): 1608 - 1614. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. J. Mehagnoul-Schipper, L. C. M. Vloet, W. N. J. M. Colier, W. H. L. Hoefnagels, and R. W. M. M. Jansen Cerebral Oxygenation Declines in Healthy Elderly Subjects in Response to Assuming the Upright Position Stroke, July 1, 2000; 31(7): 1615 - 1620. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. J. Chatterton, V. M. Pomeroy, M. J. Connolly, E. B. Faragher, L. Clayton, and R. C. Tallis The Effect of Body Position on Arterial Oxygen Saturation in Acute Stroke J. Gerontol. A Biol. Sci. Med. Sci., April 1, 2000; 55(4): 239M - 244. [Abstract] [Full Text]
|
|
|
|
 |
|
 R. A. Rodriguez, K. Snider, G. Cornel, and O. H. P. Teixeira Cerebral Blood Flow Velocity During Tilt Table Test for Pediatric Syncope Pediatrics, August 1, 1999; 104(2): 237 - 242. [Abstract] [Full Text]
|
|