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Published on: April 11, 2025
ECG signal analysis using modified S-transform
1Department of Electronics and Communication Engineering, Gayatri Vidya Parishad College of Engineering (A), Visakhapatnam, Andhra Pradesh 530048, India.
Accurate QRS complex detection is vital for heart rate variability analysis. A novel modified S-transform algorithm achieves high accuracy (99.77%) and a precise ±2 sample search back range for R-peak detection in electrocardiogram (ECG) signals.
Area of Science:
- Biomedical Engineering
- Signal Processing
- Cardiology
Background:
- Accurate QRS complex detection is crucial for analyzing heart rate variability (HRV).
- Existing transform techniques for QRS detection have limitations.
- Electrocardiogram (ECG) signal noise can impede accurate R-peak identification.
Purpose of the Study:
- To develop and evaluate a modified S-transform algorithm for precise QRS complex detection in ECG signals.
- To improve the accuracy and efficiency of R-peak localization compared to existing methods.
- To assess the performance of the proposed algorithm using key diagnostic metrics.
Main Methods:
- De-noising of the ECG signal.
- Application of a modified S-transform for QRS complex detection.
- Implementation of a search-back mechanism for R-peak verification.
- Performance evaluation using sensitivity, positive predictivity, and accuracy.
Main Results:
- The modified S-transform algorithm achieved high performance metrics: 99.91% sensitivity, 99.91% positive predictivity, and 99.77% overall accuracy.
- The integrated search-back mechanism demonstrated a highly accurate R-peak localization with a narrow range of ±2 samples.
- The proposed method shows significant improvement over previously reported algorithms in terms of accuracy and search range.
Conclusions:
- The modified S-transform is a highly effective tool for accurate QRS complex detection in ECG signals.
- The algorithm offers superior performance in R-peak localization, essential for reliable HRV analysis.
- This approach provides a robust and efficient method for cardiac rhythm monitoring and diagnostics.
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