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(Circulation. 1997;96:517-525.)
© 1997 American Heart Association, Inc.


Articles

Cardiac Atrophy After Bed-Rest Deconditioning

A Nonneural Mechanism for Orthostatic Intolerance

Benjamin D. Levine, MD; Julie H. Zuckerman, RN, RDMS; ; James A. Pawelczyk, PhD

From the Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas (Tex) and the University of Texas Southwestern Medical Center at Dallas.

Correspondence to Benjamin D. Levine, MD, Director, Institute for Exercise and Environmental Medicine, 7232 Greenville Ave, Dallas, TX 75321. E-mail Levineb{at}wpmail.phscare.org

Background The cardiovascular adaptation to bed rest leads to orthostatic intolerance, characterized by an excessive fall in stroke volume (SV) in the upright position. We hypothesized that this large fall in SV is due to a change in cardiac mechanics.

Methods and Results We measured pulmonary capillary wedge pressure (PCWP), SV, left ventricular end-diastolic volume (LVEDV), and left ventricular mass (by echocardiography) at rest, during lower-body negative pressure, and after saline infusion before and after 2 weeks of bed rest with -6° head-down tilt (n=12 subjects aged 24±5 years). Pressure (P)-volume (V) curves were modeled exponentially by P=aekV+b and logarithmically by P=-Sln[(Vm-V)/(Vm-V0], where V0 indicates volume at P=0, and the constants k and S were used as indices of normalized chamber stiffness. Dynamic stiffness (dP/dV) was calculated at baseline LVEDV. The slope of the line relating SV to PCWP during lower-body negative pressure characterized the steepness of the Starling curve. We also measured plasma volume (with Evans blue dye) and maximal orthostatic tolerance. Bed rest led to a reduction in plasma volume (17%), baseline PCWP (18%), SV (12%), LVEDV (16%), V0 (33%), and orthostatic tolerance (24%) (all P<.05). The slope of the SV/PCWP curve increased from 4.6±0.4 to 8.8±0.9 mL/mm Hg (P<.01) owing to a parallel leftward shift in the P-V curve. Normalized chamber stiffness was unchanged, but dP/dV was reduced by 50% at baseline LVEDV, and cardiac mass tended to be reduced by 5% (P<.10).

Conclusions Two weeks of head-down–tilt bed rest leads to a smaller, less distensible left ventricle but a shift to a more compliant portion of the P-V curve. This results in a steeper Starling relationship, which contributes to orthostatic intolerance by causing an excessive reduction in SV during orthostasis.


Key Words: cardiac output • pressure • cardiac volume • diastole • syncope • elasticity




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Home page
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[Abstract] [Full Text] [PDF]


Home page
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[Abstract] [Full Text] [PDF]


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[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
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[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
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[Abstract] [Full Text] [PDF]


Home page
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[Abstract] [PDF]


Home page
J. Physiol.Home page
J. F Cox, K. U. Tahvanainen, T. A Kuusela, B. D Levine, W. H Cooke, T. Mano, S. Iwase, M. Saito, Y. Sugiyama, A. C Ertl, et al.
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[Abstract] [Full Text] [PDF]


Home page
J. Physiol.Home page
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J. Physiol., January 1, 2002; 538(1): 321 - 329.
[Abstract] [Full Text] [PDF]


Home page
J. Physiol.Home page
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[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
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Vascular adaptation to microgravity: what have we learned?
J Appl Physiol, December 1, 2001; 91(6): 2415 - 2430.
[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
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Effect of short-term microgravity and long-term hindlimb unloading on rat cardiac mass and function
J Appl Physiol, September 1, 2001; 91(3): 1207 - 1213.
[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
M. A. Perhonen, F. Franco, L. D. Lane, J. C. Buckey, C. G. Blomqvist, J. E. Zerwekh, R. M. Peshock, P. T. Weatherall, and B. D. Levine
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[Abstract] [Full Text] [PDF]


Home page
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Am J Physiol Heart Circ Physiol, May 1, 2001; 280(5): H2230 - H2239.
[Abstract] [Full Text] [PDF]


Home page
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Deterioration of Left Ventricular Chamber Performance After Bed Rest : "Cardiovascular Deconditioning" or Hypovolemia?
Circulation, April 10, 2001; 103(14): 1851 - 1857.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
K.-I. Iwasaki, R. Zhang, J. H. Zuckerman, J. A. Pawelczyk, and B. D. Levine
Effect of head-down-tilt bed rest and hypovolemia on dynamic regulation of heart rate and blood pressure
Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2000; 279(6): R2189 - R2199.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
A. Kamiya, S. Iwase, D. Michikami, Q. Fu, and T. Mano
Head-down bed rest alters sympathetic and cardiovascular responses to mental stress
Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2000; 279(2): R440 - R447.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
A. Kamiya, S. Iwase, H. Kitazawa, T. Mano, O. L. Vinogradova, and I. B. Kharchenko
Baroreflex control of muscle sympathetic nerve activity after 120 days of 6{degrees} head-down bed rest
Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2000; 278(2): R445 - R452.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
J. K. Shoemaker, C. S. Hogeman, and L. I. Sinoway
Contributions of MSNA and stroke volume to orthostatic intolerance following bed rest
Am J Physiol Regulatory Integrative Comp Physiol, October 1, 1999; 277(4): R1084 - R1090.
[Abstract] [Full Text] [PDF]


Home page
NEJMHome page
P. C.A.J. Vroomen, M. C.T.F.M. de Krom, J. T. Wilmink, A. D.M. Kester, and J. A. Knottnerus
Lack of Effectiveness of Bed Rest for Sciatica
N. Engl. J. Med., February 11, 1999; 340(6): 418 - 423.
[Abstract] [Full Text] [PDF]


Home page
J. Appl. Physiol.Home page
R. Zhang, J. H. Zuckerman, J. A. Pawelczyk, and B. D. Levine
Effects of head-down-tilt bed rest on cerebral hemodynamics during orthostatic stress
J Appl Physiol, December 1, 1997; 83(6): 2139 - 2145.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
M. H. Khan, A. R. Kunselman, U. A. Leuenberger, W. R. Davidson Jr., C. A. Ray, K. S. Gray, C. S. Hogeman, and L. I. Sinoway
Attenuated sympathetic nerve responses after 24 hours of bed rest
Am J Physiol Heart Circ Physiol, June 1, 2002; 282(6): H2210 - H2215.
[Abstract] [Full Text] [PDF]


Home page
J. Physiol.Home page
B. D Levine, J. A Pawelczyk, A. C Ertl, J. F Cox, J. H Zuckerman, A. Diedrich, I. Biaggioni, C. A Ray, M. L Smith, S. Iwase, et al.
Human muscle sympathetic neural and haemodynamic responses to tilt following spaceflight
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