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Fractal fluctuations in cardiac time seriesHuman heart rate, controlled by complex feedback mechanisms, is a vital index of systematic circulation. However, it has been shown that beat-to-beat values of heart rate fluctuate continually over a wide range of time scales. Herein we use the relative dispersion, the ratio of the standard deviation to the mean, to show, by systematically aggregating the data, that the correlation in the beat-to-beat cardiac time series is a modulated inverse power law. This scaling property indicates the existence of long-time memory in the underlying cardiac control process and supports the conclusion that heart rate variability is a temporal fractal. We argue that the cardiac control system has allometric properties that enable it to respond to a dynamical environment through scaling.
Document ID
20040089008
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
West, B. J.
(Research Triangle NC 27709-2211, United States)
Zhang, R.
Sanders, A. W.
Miniyar, S.
Zuckerman, J. H.
Levine, B. D.
Blomqvist, C. G.
Date Acquired
August 21, 2013
Publication Date
August 15, 1999
Publication Information
Publication: Physica A
Volume: 270
Issue: 4-Mar
ISSN: 0378-4371
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: HL53206-03
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Cardiopulmonary
Non-NASA Center

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