Warmerdam G J J, Vullings R, Schmitt L, Van Laar J O E H, Bergmans J W M
IEEE Trans Biomed Eng. 2017 Aug;64(8):1852-1861. doi: 10.1109/TBME.2016.2626519. Epub 2016 Nov 8.
Filtering power line interference (PLI) from electrocardiogram (ECG) recordings can lead to significant distortions of the ECG and mask clinically relevant features in ECG waveform morphology. The objective of this study is to filter PLI from ECG recordings with minimal distortion of the ECG waveform.
In this paper, we propose a fixed-lag Kalman smoother with adaptive noise estimation. The performance of this Kalman smoother in filtering PLI is compared to that of a fixed-bandwidth notch filter and several adaptive PLI filters that have been proposed in the literature. To evaluate the performance, we corrupted clean neonatal ECG recordings with various simulated PLI. Furthermore, examples are shown of filtering real PLI from an adult and a fetal ECG recording.
The fixed-lag Kalman smoother outperforms other PLI filters in terms of step response settling time (improvements that range from 0.1 to 1 s) and signal-to-noise ratio (improvements that range from 17 to 23 dB). Our fixed-lag Kalman smoother can be used for semi real-time applications with a limited delay of 0.4 s.
The fixed-lag Kalman smoother presented in this study outperforms other methods for filtering PLI and leads to minimal distortion of the ECG waveform.
从心电图（ECG）记录中滤除电力线干扰（PLI）可能会导致ECG出现显著失真，并掩盖ECG波形形态中与临床相关的特征。本研究的目的是在使ECG波形失真最小的情况下，从ECG记录中滤除PLI。
在本文中，我们提出了一种具有自适应噪声估计的固定滞后卡尔曼平滑器。将这种卡尔曼平滑器在滤除PLI方面的性能与固定带宽陷波滤波器以及文献中提出的几种自适应PLI滤波器的性能进行了比较。为了评估性能，我们用各种模拟的PLI干扰干净的新生儿ECG记录。此外，还展示了从成人和胎儿ECG记录中滤除实际PLI的示例。
在阶跃响应建立时间（改善范围为0.1至1秒）和信噪比（改善范围为17至23分贝）方面，固定滞后卡尔曼平滑器优于其他PLI滤波器。我们的固定滞后卡尔曼平滑器可用于延迟有限（0.4秒）的半实时应用。
本研究中提出的固定滞后卡尔曼平滑器在滤除PLI方面优于其他方法，并且使ECG波形的失真最小。
