Noise reduction and ECG feature extraction using interpolation and Hilbert transform

An effective and reliable noise reduction and Electrocardiogram (ECG) feature extraction algorithm is proposed in this paper. Contaminated ECG samples are de-noised using a Butterworth lowpass and IIR notch filter. First derivative using Lagrange Five Point Interpolation formula and Hilbert Transform of those ECG samples are computed. Sample having maximum amplitude is found out from the transformed data and those samples having amplitude within a lead wise specific threshold of that maximum are selected. The point where those selected samples undergo slope alteration in the original time domain ECG signal is marked as R peak. After successful identification of R peak points, base line modulation correction is implemented using an empirically determined formula. Q and S points are identified by finding minimum amplitude on the either side of the most recently detected R peak. QRS onset and offset points are also detected. After detecting all these characteristic points, Heart Rate, R, Q and S peak heights and QRS duration are measured. Errors in these extracted ECG features are also calculated. The algorithm offers a good level of Sensitivity (99.84%), Positive Predictivity (99.84%) and Detection Accuracy (99.84%) of R peak. Different types of ECG data of all the 12 leads taken from PTB diagnostic ECG database (PTB-DB) is used for testing the performance of the proposed module.

[1]  M. Mitra,et al.  An ECG data compression method via R-Peak detection and ASCII Character Encoding , 2011, 2011 International Conference on Computer, Communication and Electrical Technology (ICCCET).

[2]  Truong Q. Nguyen,et al.  Comparing stress ECG enhancement algorithms , 1996 .

[3]  G.G. Cano,et al.  An approach to cardiac arrhythmia analysis using hidden Markov models , 1990, IEEE Transactions on Biomedical Engineering.

[4]  Morteza Shahram,et al.  ECG beat classification based on a cross-distance analysis , 2001, Proceedings of the Sixth International Symposium on Signal Processing and its Applications (Cat.No.01EX467).

[5]  P Jafari Moghadam Fard,et al.  A novel approach in R peak detection using Hybrid Complex Wavelet (HCW). , 2008, International journal of cardiology.

[6]  Leo Schamroth,et al.  An introduction to electrocardiography , 1976 .

[7]  Madhuchhanda Mitra,et al.  ECG signal compression using ASCII character encoding and transmission via SMS , 2013, Biomed. Signal Process. Control..

[8]  H. Gholam-Hosseini,et al.  ECG noise cancellation using digital filters , 1998, Proceedings of the 2nd International Conference on Bioelectromagnetism (Cat. No.98TH8269).

[9]  S. K. Mukhopadhyay,et al.  Time plane ECG feature extraction using Hilbert transform, variable threshold and slope reversal approach , 2011, 2011 International Conference on Communication and Industrial Application.

[10]  P.E. Trahanias,et al.  An approach to QRS complex detection using mathematical morphology , 1993, IEEE Transactions on Biomedical Engineering.

[11]  J.P. Marques de Sa,et al.  ECG noise filtering using wavelets with soft-thresholding methods , 1999, Computers in Cardiology 1999. Vol.26 (Cat. No.99CH37004).

[12]  Mahadev D. Uplane,et al.  Design and implementation of digital FIR equiripple notch filter on ECG signal for removal of power line interference , 2008 .

[13]  E. Skordalakis,et al.  Bottom-up approach to the ECG pattern-recognition problem , 2006, Medical and Biological Engineering and Computing.

[14]  R. Warlar,et al.  Integer coefficient bandpass filter for the simultaneous removal of baseline wander, 50 and 100 Hz interference from the ECG , 1991, Medical and Biological Engineering and Computing.

[15]  Willis J. Tompkins,et al.  Biomedical Digital Signal Processing , 1993 .

[16]  Allan Kardec Barros,et al.  independent , 2006, Gumbo Ya Ya.

[17]  S. K. Mukhopadhyay,et al.  An ECG signal compression technique using ASCII character encoding , 2012 .

[18]  F. Gritzali Towards a generalized scheme for QRS detection in ECG waveforms , 1988 .

[19]  Cuiwei Li,et al.  Detection of ECG characteristic points using wavelet transforms , 1995, IEEE Transactions on Biomedical Engineering.

[20]  S. Griffis EDITOR , 1997, Journal of Navigation.

[21]  George Carayannis,et al.  QRS detection through time recursive prediction techniques , 1988 .

[22]  Patrick Gaydecki,et al.  The use of the Hilbert transform in ECG signal analysis , 2001, Comput. Biol. Medicine.

[23]  Ali Ghaffari,et al.  A new mathematical based QRS detector using continuous wavelet transform , 2008, Comput. Electr. Eng..

[24]  S. K. Mukhopadhyay,et al.  ECG feature extraction using differentiation, Hilbert transform, variable threshold and slope reversal approach , 2012, Journal of medical engineering & technology.

[25]  Pablo Laguna,et al.  Bioelectrical Signal Processing in Cardiac and Neurological Applications , 2005 .

[26]  Mohammad Bagher Shamsollahi,et al.  Multiadaptive Bionic Wavelet Transform: Application to ECG Denoising and Baseline Wandering Reduction , 2007, EURASIP J. Adv. Signal Process..

[27]  G. Boudreaux-Bartels,et al.  Wavelet transform-based QRS complex detector , 1999, IEEE Transactions on Biomedical Engineering.

[28]  C. Li,et al.  Detection of ECG characteristic points using wavelet transforms. , 1995, IEEE transactions on bio-medical engineering.

[29]  M. Mitra,et al.  ECG signal processing: Lossless compression, transmission via GSM network and feature extraction using Hilbert transform , 2013, 2013 IEEE Point-of-Care Healthcare Technologies (PHT).

[30]  Antonio Albiol,et al.  A new adaptive scheme for ECG enhancement , 1999, Signal Process..

[31]  P. E. Tikkanen,et al.  Nonlinear wavelet and wavelet packet denoising of electrocardiogram signal , 1999, Biological Cybernetics.

[32]  P. Laguna,et al.  Adaptive estimation of QRS complex wave features of ECG signal by the hermite model , 2007, Medical and Biological Engineering and Computing.

[33]  Leslie Tung,et al.  A novel algorithm for cardiac biosignal filtering based on filtered residue method , 2002, IEEE Transactions on Biomedical Engineering.

[34]  Somnath Ghosh,et al.  LOSSLESS ELECTROCARDIOGRAM COMPRESSION TECHNIQUE AND GSM BASED TELE-CARDIOLOGY APPLICATION , 2013 .

[35]  S. K. Mukhopadhyay,et al.  ECG Compression Technique Using ASCII Character Encoding and Transmission Using GSM Transmitter , 2013 .

[36]  S. Mitra,et al.  An ECG Data Compression Method via Standard Deviation and ASCII Character Encoding , 2011, 2011 Second International Conference on Emerging Applications of Information Technology.

[37]  Sarabjeet Singh Mehta,et al.  Identification of QRS complexes in 12-lead electrocardiogram , 2009, Expert Syst. Appl..

[38]  Jacek M. Leski,et al.  ECG baseline wander and powerline interference reduction using nonlinear filter bank , 2005, Signal Process..

[39]  Pablo Laguna,et al.  A wavelet-based ECG delineator: evaluation on standard databases , 2004, IEEE Transactions on Biomedical Engineering.

[40]  Zhongwei Jiang,et al.  Development of QRS detection algorithm designed for wearable cardiorespiratory system , 2009, Comput. Methods Programs Biomed..

[41]  S. Mitra,et al.  QRS complex identification using Hilbert transform, variable threshold and slope reversal approach , 2012 .

[42]  Alina Momot,et al.  Methods of weighted averaging of ECG signals using Bayesian inference and criterion function minimization , 2009, Biomed. Signal Process. Control..

[43]  Manuel Blanco-Velasco,et al.  ECG signal denoising and baseline wander correction based on the empirical mode decomposition , 2008, Comput. Biol. Medicine.

[44]  Karen O. Egiazarian,et al.  Improving the transform domain ECG denoising performance by applying interbeat and intra-beat decorrelating transforms , 2001, ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196).

[45]  J. Leski Robust weighted averaging. , 2002, IEEE transactions on bio-medical engineering.

[46]  Madhuchhanda Mitra,et al.  A lossless ECG data compression technique using ASCII character encoding , 2011, Comput. Electr. Eng..

[47]  Jacek M. Leski Robust weighted averaging [of biomedical signals] , 2002, IEEE Transactions on Biomedical Engineering.