Memory beyond memory in heart beating: an efficient way to detect pathological conditions

P. Allegrini; P. Grigolini; P. Hamilton; L. Palatella; G. Raffaelli

doi:10.1103/physreve.65.041926

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Memory beyond memory in heart beating: an efficient way to detect pathological conditions

P. Allegrini·P. Grigolini·P. Hamilton·L. Palatella·G. Raffaelli

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Abstract

We study the long-range correlations of heartbeat fluctuations with the method of diffusion entropy. We show that this method of analysis yields a scaling parameter $δ$ that apparently conflicts with the direct evaluation of the distribution of times of sojourn in states with a given heartbeat frequency. The strength of the memory responsible for this discrepancy is given by a parameter $ε^{2}$, which is derived from real data. The distribution of patients in the ($δ$, $ε^{2}$)-plane yields a neat separation of the healthy from the congestive heart failure subjects.

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BibTeX RIS

P. Allegrini, P. Grigolini, P. Hamilton, L. Palatella, G. Raffaelli. 2001-07-30. Memory beyond memory in heart beating: an efficient way to detect pathological conditions. https://doi.org/10.1103/physreve.65.041926

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