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Automated Diagnosis of Heart Sounds Using Rule-Based Classification Tree
Mohamed Esmail Karar1, Sahar H El-Khafif2, Mohamed A El-Brawany2
1Faculty of Electronic Engineering (FEE), Menoufia University, Menouf, 32952, Egypt. mekarar@ieee.org.
Insights
This study introduces an automated method for heart sound analysis, classifying heart status using a rule-based tree. The system achieves 95.5% accuracy in diagnosing normal and abnormal heart conditions.
Area of Science:
- Biomedical Engineering
- Cardiology
- Signal Processing
Background:
- Accurate heart sound analysis is crucial for diagnosing cardiac conditions.
- Automated methods can improve the efficiency and consistency of heart sound diagnosis.
Purpose of the Study:
- To develop an automated method for classifying heart status using heart sound signals.
- To differentiate between normal heart sounds and specific abnormalities: aortic valve stenosis, aortic insufficiency, and ventricular septum defect.
Main Methods:
- Automatic detection and segmentation of heart sound signal cycles.
- Preprocessing using discrete wavelet transform and calculation of largest Lyapunov exponents for feature extraction.
- Classification using a rule-based decision tree based on extracted dynamical features.
Main Results:
- The developed automated method successfully classified heart sound signals.
- Achieved a high success rate of 95.5% on twenty-two datasets of normal and abnormal heart sounds.
- Demonstrated that classification rules can be modified to further improve diagnostic accuracy.
Conclusions:
- The proposed rule-based classification tree offers an effective automated approach for heart sound diagnosis.
- Largest Lyapunov exponents derived from heart sound time series are valuable dynamical features for classification.
- The method shows potential for improving the accuracy and accessibility of automated cardiac diagnosis.
Abstract:
In order to assist the diagnosis procedure of heart sound signals, this paper presents a new automated method for classifying the heart status using a rule-based classification tree into normal and three abnormal cases; namely the aortic valve stenosis, aortic insufficient, and ventricular septum defect. The developed method includes three main steps as follows. First, one cycle of the heart sound signals is automatically detected and segmented based on time properties of the heart signals. Second, the segmented cycle is preprocessed with the discrete wavelet transform and then largest Lyapunov exponents are calculated to generate the dynamical features of heart sound time series. Finally, a rule-based classification tree is fed by these Lyapunov exponents to give the final decision of the heart health status. The developed method has been tested successfully on twenty-two datasets of normal heart sounds and murmurs with success rate of 95.5%. The resulting error can be easily corrected by modifying the classification rules; consequently, the accuracy of automated heart sounds diagnosis is further improved.
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