Impedance cardiography signal denoising using discrete wavelet transform

Souhir Chabchoub1, Sofienne Mansouri2, Ridha Ben Salah3

  • 1University of Tunis El-Manar, ISTMT, Laboratory of Biophysics and Medical Technologies, Tunis, Tunisia. chabchoub_souhir@yahoo.fr.

Insights

This study compares wavelet denoising methods for impedance cardiography (ICG) signals. The Daubechies (db8) wavelet family effectively reduces noise, improving cardiovascular disease diagnosis accuracy.

Area of Science:

  • Biomedical Engineering
  • Signal Processing
  • Cardiology

Background:

  • Impedance cardiography (ICG) is a non-invasive diagnostic tool for cardiovascular diseases.
  • ICG signal acquisition is susceptible to noise, hindering accurate hemodynamic parameter determination and diagnosis.
  • Inaccurate ICG waveform recognition leads to misdiagnosis of cardiovascular conditions.

Purpose of the Study:

  • To identify the most effective wavelet-based denoising method for impedance cardiography signals.
  • To evaluate and compare various wavelet families for ICG signal noise reduction.
  • To assess the performance of the best wavelet method against traditional filtering techniques.

Main Methods:

  • Tested Haar, Daubechies (db2-db8), Symlet (sym2-sym8), and Coiflet (coif2-coif5) wavelet families for denoising.
  • Compared the optimal wavelet family with Savitzky-Golay and median filtering.
  • Evaluated methods using signal-to-noise ratio (SNR), root-mean-square error (RMSE), and percent-difference root-mean-square (PRD).

Main Results:

  • The Daubechies wavelet family, specifically db8, demonstrated superior performance in noise reduction.
  • Daubechies (db8) outperformed other tested wavelet families and traditional filtering methods.
  • Quantitative metrics (SNR, RMSE, PRD) confirmed the effectiveness of the db8 wavelet.

Conclusions:

  • The Daubechies (db8) wavelet is the most suitable method for denoising impedance cardiography signals.
  • Effective ICG signal denoising enhances the accuracy of hemodynamic parameter calculation.
  • Improved signal quality facilitates more reliable diagnosis of cardiovascular diseases.

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