Curvature Analysis of Multifractal Spectra for Time Series of RR Intervals for Patients with Congestive Heart Failure

Abstract

Multifractal analysis have been used to study time series of physiological systems such as the series of heartbeat intervals. Using the multifractal formalism we analyze RR interval time series from 54 healthy subjects and 44 patients with congestive heart failure (CHF). Their multifractal spectra were calculated for each time series and it was observed that around the maximum of the multifractal spectra of healthy subjects, the spectra are smooth but the multifractal spectra of CHF patients tended to be pointed, therefore it is proposed to measure the curvature of all multifractal spectra. We conclude that this parameter provides information about the health state of the persons in the sample.