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[A heart sound classification method based on complete ensemble empirical modal decomposition with adaptive noise
Meijun Liu1, Quanyu Wu1, Sheng Ding1
1Institute of Bioinformatics and Medical Engineering, School of Electrical and Information Engineering, Jiangsu University of Technology, Changzhou, Jiangsu 213001, P. R. China.
A novel method using Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) permutation entropy enhances phonocardiogram (PCG) classification accuracy. This approach significantly improves heart sound signal analysis compared to traditional methods.
Area of Science:
- Biomedical Engineering
- Signal Processing
- Cardiology
Background:
- Heart sound signals (phonocardiograms, PCG) are complex physiological signals.
- These signals exhibit nonlinear and nonstationary characteristics, posing challenges for accurate classification.
- Existing methods for PCG analysis may lack efficiency and precision.
Purpose of the Study:
- To develop a novel and efficient method for phonocardiogram (PCG) classification.
- To improve the accuracy of heart sound signal analysis.
- To leverage advanced signal decomposition and entropy analysis for enhanced feature extraction.
Main Methods:
- Utilized Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) to decompose PCG signals into intrinsic mode functions (IMFs).
- Sifted IMFs based on correlation coefficient, energy factor, and signal-to-noise ratio for optimal selection.
- Extracted instantaneous frequency via Hilbert transform and computed permutation entropy to form eigenvectors for Support Vector Machine (SVM) classification.
Main Results:
- The proposed CEEMDAN permutation entropy method achieved an accuracy rate of up to 87% in PCG classification.
- Demonstrated a significant improvement in accuracy, an increase of 18%-24%, compared to traditional Empirical Mode Decomposition (EMD) and Ensemble Empirical Mode Decomposition (EEMD) methods.
- Validated the method's effectiveness using 100 PCG samples from the 2016 PhysioNet/CinC Challenge.
Conclusions:
- The CEEMDAN permutation entropy method offers a highly accurate and efficient approach for phonocardiogram classification.
- This technique effectively captures the nonlinear and nonstationary features of heart sound signals.
- The proposed method represents a significant advancement in automated cardiac auscultation and diagnosis.
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