|
|
||||||||
1Department of Physiology, Academic Medical Center, University of Amsterdam; and 2BMEYE, Academic Medical Center, Amsterdam, The Netherlands
Submitted 20 July 2005 ; accepted in final form 18 May 2006
Noninvasive finger blood pressure has become a surrogate for central blood pressure under widely varying circumstances. We tested the validity of finger-aorta transfer functions (TF) to reconstruct aortic pressure in seven cardiac patients before, during, and after incremental bicycle exercise. The autoregressive exogenous model method was used for calculating finger-aorta TFs. Finger pressure was measured noninvasively using Finapres and aortic pressure using a catheter-tip manometer. When applying the individual TFs found during rest for reconstruction of aortic pressure during all workloads, systolic pressure was increasingly underestimated, with large variation between subjects: +4.0 to 18.1 mmHg. In most subjects, diastolic pressure was overestimated: 3.9 to +5.5 mmHg. Pulse pressure estimation varied between +4.5 and 21.9 mmHg. In all cases, wave distortion was present. Postexercise, error in reconstructed aortic systolic pressure slowly declined, and diastolic pressure was overestimated. During rest, the TF gain had a minimum between 3.65 and 4.85 Hz (Fmin). During exercise, Fmin shifted to frequencies between 4.95 and 7.15 Hz at the maximum workload, with no change in gain. Postexercise, gain in most subjects shifted to values closer to unity, whereas Fmin did not return to resting values. Within each subject, aorta-Finapres travel time was linearly related to mean pressure. During exercise, Fmin was linearly related to both delay and heart rate. We conclude that, during increasing exercise, rest TFs give an increasingly unreliable reconstruction of aortic pressure, especially at higher heart rates.
autoregressive exogenous
This article has been cited by other articles:
![]() |
B. E. Westerhof, I. Guelen, W. J. Stok, H. A. J. Lasance, C. A. P. L. Ascoop, K. H. Wesseling, N. Westerhof, W. J. W. Bos, N. Stergiopulos, and J. A. E. Spaan Individualization of transfer function in estimation of central aortic pressure from the peripheral pulse is not required in patients at rest J Appl Physiol, December 1, 2008; 105(6): 1858 - 1863. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Munir, B. Jiang, A. Guilcher, S. Brett, S. Redwood, M. Marber, and P. Chowienczyk Exercise reduces arterial pressure augmentation through vasodilation of muscular arteries in humans Am J Physiol Heart Circ Physiol, April 1, 2008; 294(4): H1645 - H1650. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |