Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Quantification of cardiorespiratory interactions based on joint symbolic dynamics
Author: Kabir, M.
Saint, D.
Nalivaiko, E.
Abbott, D.
Voss, A.
Baumert, M.
Citation: Annals of Biomedical Engineering, 2011; 39(10):2604-2614
Publisher: American Institute of Physics
Issue Date: 2011
ISSN: 0090-6964
Statement of
Muammar M. Kabir, David A. Saint, Eugene Nalivaiko, Derek Abbott, Andreas Voss and Mathias Baumert
Abstract: Cardiac and respiratory rhythms are highly nonlinear and nonstationary. As a result traditional time-domain techniques are often inadequate to characterize their complex dynamics. In this article, we introduce a novel technique to investigate the interactions between R-R intervals and respiratory phases based on their joint symbolic dynamics. To evaluate the technique, electrocardiograms (ECG) and respiratory signals were recorded in 13 healthy subjects in different body postures during spontaneous and controlled breathing. Herein, the R-R time series were extracted from ECG and respiratory phases were obtained from abdomen impedance belts using the Hilbert transform. Both time series were transformed into ternary symbol vectors based on the changes between two successive R-R intervals or respiratory phases. Subsequently, words of different symbol lengths were formed and the correspondence between the two series of words was determined to quantify the interaction between cardiac and respiratory cycles. To validate our results, respiratory sinus arrhythmia (RSA) was further studied using the phase-averaged characterization of the RSA pattern. The percentage of similarity of the sequence of symbols, between the respective words of the two series determined by joint symbolic dynamics, was significantly reduced in the upright position compared to the supine position (26.4 ± 4.7 vs. 20.5 ± 5.4%, p < 0.01). Similarly, RSA was also reduced during upright posture, but the difference was less significant (0.11 ± 0.02 vs. 0.08 ± 0.01 s, p < 0.05). In conclusion, joint symbolic dynamics provides a new efficient technique for the analysis of cardiorespiratory interaction that is highly sensitive to the effects of orthostatic challenge.
Keywords: Heart; Heart rate variability; Coupling; Breathing frequency; Respiratory sinus arrhythmia
Rights: © 2011 Biomedical Engineering Society
RMID: 0020114435
DOI: 10.1007/s10439-011-0332-3
Grant ID:
Appears in Collections:Electrical and Electronic Engineering publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.