A low-distortion filter method to reject muscle noise in multi-lead electrocardiogram systems

This paper proposes a low-distortion filter method for rejection of muscle noise in multilead electrocardiogram (ECG) systems. This approach combines low-pass filtering with a modified version of source consistency filtering. The low-pass filtering splits the raw ECG signal into a muscle-noise-free part and a muscle-noise-overlapping part. The modified source consistency filtering then extracts the signal components from the muscle-noise-overlapping part. The extracted signal components are restored to the muscle-noise-free part as the output. The performance of our method was verified with simulated and clinically recorded ECG signals. The simulated ECG signals were created from computer simulation using three-dimensional, realistically shaped heart and torso models. The ideal signals are superimposed with white noise to simulate muscle noise and with a low frequency sine wave to simulate baseline drift. For verification, our method was compared with Butterworth low-pass filters. The results show that our method can effectively reduce muscle noise with less distortion of the QRS wave than conventional low-pass filters.