Comparison of ECG Baseline Wander Removal Techniques and Improvement Based on Moving Average of Wavelet Approximation Coefficients (original) (raw)

PERFORMANCE CALCULATION OF WAVELET TRANSFORMS FOR REMOVAL OF BASELINE WANDER FROM ECG

International Journal of …, 2012

As change in ST segment is an indication of ischemia in ECG and usually baseline wanders which are low frequency component of 0.5 to 1 Hz signal overlaps the ST segment in ECG, when the ECG is recorded by the electrodes from the chest of the patient. So Baseline wanders may makes wrong interpretation for the detection of ischemia and removal of baseline wander may cause another loss of important clinical information. This paper is to present the wavelet transform for estimation of baseline wanders in ECG and to find the effectiveness of this method by the Percent Root Mean Square Difference (PRD). Obtained results show that the wavelet transform approach performs successfully removal of baseline wanders. To test the proposed method, ECG signals obtained from European ST-T database have been used.

REMOVING BASELINE WANDER FROM ECG SIGNAL USING WAVELET TRANSFORM

REMOVING BASELINE WANDER FROM ECG SIGNAL USING WAVELET TRANSFORM, 2019

Electrocardiogram (ECG) signal is the representation of electrical activity generated by heart muscles, which is primarily utilized to detect cardiac abnormalities. Due to the sensitive nature of ECG, its important features are affected by different noises and create problems for diagnosis. This study proposes biorthogonal wavelet family by investigating different wavelet families to reduce baseline wander from the ECG signal. The proposed approach performance is compared to adaptive normalized least-mean-square (NLMS) and notch filters. Different performance parameters, such as amplitude spectrum, magnitude squared coherence (MSC), and power spectral density (PSD) has been evaluated. Signal-to-noise ratio (SNR), percentage root-mean-square difference (PRD), mean-square-error (MSE), normalized mean-square-error (NMSE), root mean-square-error (RMSE), and normalized root mean-square-error (NRMSE) performance parameters are calculated as well. The SNR values of the reconstructed ECG signal are-0.0046 dB and 1.6122 dB for notch and adaptive NLMS filters, respectively, which are lower than that of 8.0464 dB for the biorthogonal wavelet transform. Similarly, the MSC values are 0.091903 and 0.44522 after notch and adaptive NLMS filtrations, respectively, which are lower than those of 0.8913 after wavelet filtration. Also, the PSD value for the wavelet transform is-9.317 dB/Hz, which is better than that of adaptive NLMS (-6.788 dB/Hz) and notch (-6.669 dB/Hz) filters. Therefore, the analysis based on performance parameters has justified that proposed biorthogonal wavelet family represent better performance for reducing baseline wander from the ECG signal than adaptive NLMS and notch filters.

Baseline wander removal methods for ECG signals: A comparative study

arXiv (Cornell University), 2018

Cardiovascular diseases are the leading cause of death worldwide, accounting for 17.3 million deaths per year. The electrocardiogram (ECG) is a non-invasive technique widely used for the detection of cardiac diseases. To increase diagnostic sensitivity, ECG is acquired during exercise stress tests or in an ambulatory way. Under these acquisition conditions, the ECG is strongly affected by some types of noise, mainly by baseline wander (BLW). In this work were implemented nine methods widely used for the elimination of BLW, which are: interpolation using cubic splines, FIR filter, IIR filter, least mean square adaptive filtering, moving-average filter, independent component analysis, interpolation and successive subtraction of median values in RR interval, empirical mode decomposition, and wavelet filtering. For the quantitative evaluation, the following similarity metrics were used: absolute maximum distance, the sum of squares of distances and percentage root-mean-square difference. Several experiments were performed using synthetic ECG signals generated by ECGSYM software, real ECG signals from QT Database, artificial BLW generated by the software and real BLW from the Noise Stress Test Database. The best results were obtained by the method based on FIR highpass filter with a cutoff frequency of 0.67 Hz.

Electrocardiogram baseline wander removal using stationary wavelet approximations

2010

In this paper, a method to reduce the baseline wandering of an electrocardiogram signal is presented. The described method is based on stationary wavelet approximation of the whole signal. The main advantage of this method, compared with others, is the fact that it is a non-supervised method, allowing the process to be used in an automatic analysis of electrocardiograms. Moreover, the results are as accurate as those obtained with other methods of baseline wandering removal, methods considered as references in the scientific bibliography.

Comparisons of Different Approaches for Removal of Baseline Wander from ECG Signal

Baseline wandering can mask some important features of the Electrocardiogram (ECG) signal hence it is desirable to remove this noise for proper analysis and display of the ECG signal. This paper presents the implementation and evaluation of different methods to remove this noise. The parameters i.e. Power Spectral density (PSD), average Power & Signal to noise ratio (SNR) are calculated of signals to compare the performance of different filtering methods. IIR zero phase filtering has been proved efficient method for the removal of Baseline wander from ECG signal. The results have been concluded using Matlab software and MIT-BIH arrhythmia database.

Comparison of different approaches for removal of baseline wander from ECG signal

Proceedings of the International Conference & Workshop on Emerging Trends in Technology - ICWET '11, 2011

Baseline wandering can mask some important features of the Electrocardiogram (ECG) signal hence it is desirable to remove this noise for proper analysis and display of the ECG signal. This paper presents the implementation and evaluation of different methods to remove this noise. The parameters i.e. Power Spectral density (PSD), average Power & Signal to noise ratio (SNR) are calculated of signals to compare the performance of different filtering methods. IIR zero phase filtering has been proved efficient method for the removal of Baseline wander from ECG signal. The results have been concluded using Matlab software and MIT-BIH arrhythmia database.

Real Time Analysis of ECG Signal for Baseline Wander Removal and R Peak Detection Using Discrete Wavelet Transform

2016

Inspiration of this project is from the need to find an efficient method for analysis of ECG signal which needs to be simple, have good accuracy and have less computational time. As the main cause of death around the globe is being led by heart related diseases, hence a recent study shows that in the working age group of around 24-65 years, the death percentage of 25 is only because of the various heart related diseases. Hence ECG is the most important signal for consideration and observation to prevent these issues. ECG is a bio medical signal which can be detected by using electrodes placed in the particular locations of human body. In my research work there are two stages for the efficient analysis of ECG signal. Primary stage is the enhancement of ECG signal, that is removal of noise. It is done by extracting the required cardiac components by rejecting the background noises mainly Baseline Wander noise which is a low frequency noise and generally lies below 0.5 Hz. This is done...

Comparison of Baseline Wander Removal Techniques considering the Preservation of ST Changes in the Ischemic ECG: A Simulation Study

Computational and Mathematical Methods in Medicine, 2017

The most important ECG marker for the diagnosis of ischemia or infarction is a change in the ST segment. Baseline wander is a typical artifact that corrupts the recorded ECG and can hinder the correct diagnosis of such diseases. For the purpose of finding the best suited filter for the removal of baseline wander, the ground truth about the ST change prior to the corrupting artifact and the subsequent filtering process is needed. In order to create the desired reference, we used a large simulation study that allowed us to represent the ischemic heart at a multiscale level from the cardiac myocyte to the surface ECG. We also created a realistic model of baseline wander to evaluate five filtering techniques commonly used in literature. In the simulation study, we included a total of 5.5 million signals coming from 765 electrophysiological setups. We found that the best performing method was the wavelet-based baseline cancellation. However, for medical applications, the Butterworth high...

Baseline Drift Removal and De-Noising of the ECG Signal using Wavelet Transform

ECG signal plays an important role in the primary diagnosis and analysis of heart diseases. When an Electrocardiogram is recorded many kinds of noise are recorded. The aim of this paper is to use discrete wavelet transform (DWT) for de-noising the ECG signal. Text formatted ECG signals of ten second duration are taken from the MIT-BIH arrhythmia database. ECG signal of Modified lead II (MLII) are chosen for processing. For wavelet transform, daubechies wavelets were used because the scaling functions of this wavelet filter are similar to the shape of the ECG. From the decomposition of the ECG signal it was seen that the low frequency component cause the baseline shift, theses component were deducted to get a signal without baseline drift. Also the high frequency components of the signal were removed for getting denoised signal. A program has been developed with MATLAB software for this work.

Baseline Drift Removal of ECG Signal

Research Advances in the Integration of Big Data and Smart Computing, 2016

The filtering techniques are primarily used for preprocessing of the signal and have been implemented in a wide variety of systems for Electrocardiogram (ECG) analysis. It should be remembered that filtering of the ECG is contextual and should be performed only when the desired information remains undistorted. Removal of baseline drift is required in order to minimize changes in beat morphology that do not have cardiac origin, which is especially important when subtle changes in the ''low-frequency'' ST segment are analyzed for the diagnosis of ischemia. Here, for baseline drift removal different filters such as Median, Low Pass Butter Worth, Finite Impulse Response (FIR), Weighted Moving Average and Stationary Wavelet Transform (SWT) are implemented. The fundamental properties of signal before and after baseline drift removal are statistically analyzed.