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Heart sound recognition technology based on convolutional neural network
Ximing Huai1, Satoshi Kitada2, Dongeun Choi3
1Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto, Japan.
Insights
This study introduces a novel convolutional neural network algorithm for classifying heart sound signals, achieving high accuracy. This AI-driven approach aids in early heart disease detection and diagnosis, potentially reducing mortality rates.
Area of Science:
- Cardiology
- Artificial Intelligence
- Biomedical Signal Processing
Background:
- Rising heart disease mortality rates necessitate improved diagnostic tools.
- Heart sound auscultation is a fundamental clinical skill for diagnosing cardiac conditions.
- Current diagnostic methods require enhancement for greater accuracy and accessibility.
Purpose of the Study:
- To develop and evaluate a convolutional neural network (CNN) algorithm for accurate heart sound signal classification.
- To improve the efficiency and effectiveness of diagnosing heart disease through automated auscultation analysis.
- To provide a supplementary tool for clinicians in identifying cardiac abnormalities.
Main Methods:
- Collected clinical and literature-based heart sound data.
- Preprocessed heart sound signals into 5-second grayscale images.
- Trained and optimized a CNN model using the prepared datasets.
- Evaluated the CNN model's performance on a separate test set.
Main Results:
- The CNN achieved a training accuracy of 95.17% and a loss of 0.23.
- Testing yielded an accuracy of 94.80%, sensitivity of 94.29%, and specificity of 95.54%.
- The algorithm demonstrated superior accuracy and sensitivity compared to existing methods, with an AUC of 0.943.
Conclusions:
- The proposed CNN algorithm effectively classifies heart sound signals.
- This method shows significant potential for assisting in heart sound auscultation and early heart disease diagnosis.
- The findings suggest a valuable application of AI in improving cardiovascular diagnostics.
Abstract:
The mortality rate of heart disease continues to rise each year: developing mechanisms to reduce mortality from heart disease is a top concern in today's society. Heart sound auscultation is a crucial skill used to detect and diagnose heart disease. In this study, we propose a heart sound signal classification algorithm based on a convolutional neural network. The algorithm is based on heart sound data collected in the clinic and from medical books. The heart sound signals were first preprocessed into a grayscale image of 5 seconds. The training samples were then used to train and optimize the convolutional neural network; obtaining a training result with an accuracy of 95.17% and a loss value of 0.23. Finally, the convolutional neural network was used to test the test set samples. The results showed an accuracy of 94.80%, sensitivity of 94.29%, specificity of 95.54%, precision of 93.44%, F1_score of 93.84%, and an AUC of 0.943. Compared with other algorithms, the accuracy and sensitivity of the algorithms were improved. This shows that the method used in this study can effectively classify heart sound signals and could prove useful in assisting heart sound auscultation.
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S2 (Second Heart Sound)-
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