Heart rate transition patterns reveal autonomic dysfunction in heart failure with renal function decline: a symbolic and Markov model approach

Figures

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  Fig. 1. Graphical summary of the methodology. In this study, we calculated heart rates (HR) from 5-minute electrocardiogram (ECG) records of 358 chronic heart failure patients (CHF). The patients were divided based on estimated glomerular filtration rate into three groups to compare HR transition dynamics across different renal function. The dynamics were investigated after digitizing HR based on their acceleration/deceleration patterns

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  Fig. 2. Comparison of transition probabilities for heart rate (HR) dynamics/transitions across different renal function stages. Transitions were derived using a first-order Markov model with three states: -1 (HR deceleration), 0 (no change), and 1 (HR acceleration). Significant differences between groups are indicated by red asterisks (*). The figure shows monotonic runs (-1 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:\to\:$$\end{document} -1, 1 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:\to\:$$\end{document} 1) declined, while tonic changes (-1 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:\to\:$$\end{document} 1, 1…

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  Fig. 3. Transition Stability Index (TSI) vs. Low Frequency (LF) by Renal Function Stage. Scatter plot showing the relationship between log-transformed LF power and the TSI across kidney function stages. Each dot represents an individual subject, coloured by group: normal kidney function (blue), Stage 2 (S2) (orange), and Stage 3 (S3) (yellow). Ellipses indicate ± 1 standard deviation around the mean of each group, highlighting the variability in TSI and LF. The downward trend in TSI with renal function decline suggests reduced directional stability of heart rate (HR)

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  Fig. 4. Motif frequency distribution of heart rate (HR) transition sequences across kidney function stages