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Long-range dependencies in heart rate signals- revisited

Danuta Makowiec·Rafal Galaska·Aleksandra Dudkowska·Andrzej Rynkiewicz·Marcin Zwierz
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Abstract

The RR series extracted from human electrocardiogram signal (ECG) is considered as a fractal stochastic process. The manifestation of long-range dependencies is the presence of power laws in scale dependent process characteristics. Exponents of these laws: $β$ - describing power spectrum decay, $α$ - responsible for decay of detrended fluctuations or $H$ related to, so-called, roughness of a signal, are known to differentiate hearts of healthy people from hearts with congestive heart failure. There is a strong expectation that resolution spectrum of exponents, so-called, local exponents in place of global exponents allows to study differences between hearts in details. The arguments are given that local exponents obtained in multifractal analysis by the two methods: wavelet transform modulus maxima (WTMM) and multifractal detrended fluctuation analysis (MDFA), allow to recognize the following four stages of the heart: healthy and young, healthy and advance in years, subjects with left ventricle systolic dysfunction (NYHA I--III class) and characterized by severe congestive heart failure (NYHA III-IV class).

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Danuta Makowiec, Rafal Galaska, Aleksandra Dudkowska, Andrzej Rynkiewicz, Marcin Zwierz. 2005-10-24. Long-range dependencies in heart rate signals- revisited. https://doi.org/10.1016/j.physa.2006.02.038

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