ECG Enhancement and R-Peak Detection Based on Window Variability

Figures

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  Figure 1. The main waveform in an ECG signal. P wave—Indicates atrial depolarization, or contraction of the atrium; QRS complex—Indicates ventricular depolarization, or contraction of the ventricles; T wave—Indicates ventricular repolarization.

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  Figure 2. Flowchart of the proposed method. WVT—window variance transform signal.

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  Figure 3. Comparison of original signal and the transformed signals, (a) Original signal of 104 from MIT-BIH database. (b) WVT—window variance transform signal. (c) SWVT—squared window variance transform signal.

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  Figure 4. Comparison of original signal and the transformed signals, (a) Original signal of 207 from MIT-BIH database. (b) WVT—window variance transform signal. (c) SWVT—squared window variance transform signal.

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  Figure 5. The R-peak detection results of 101 for different detectors on MIT-BIH database (a red X represents the wrongly identified R peak; a red rectangle is the missing R peak). TP—true positive (correctly identified R peak); FN—false negative (missing R peak); FP—false positive (wrongly identified R peak); SEN—sensitivity; PPV—positive predicative value; CSI—cumulative statistical index.

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  Figure 6. The R-peak detection results of 208 record for different detectors (a red rectangle is the missing R-peak). TP—true positive (correctly identified R peak); FN—false negative (missing R peak); FP—false positive (wrongly identified R peak); SEN—sensitivity; PPV—positive predicative value; CSI—cumulative statistical index.

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  Figure 7. The comparison of QRS complexs distributions with P/T waves. All waves were extracted from the qtdb dataset: (a) amplitude; (b) kurtosis.

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  Figure 8. The performance with different α for SEN (sensitivity), PPV (positive predicative value) and CSI (cumulative statistical index). P wave—Indicates atrial depolarization, or contraction of the atrium; QRS complex—Indicates ventricular depolarization, or contraction of the ventricles; T wave—Indicates ventricular repolarization.