Efficient and fast ECG baseline wander reduction without distortion of important clinical information

Baseline wander makes manual and automatic analysis of ECG records difficult, especially the measuring of ST-segment deviation. Since the spectrum of baseline wander and low frequency component of ECG signal usually overlaps, removing of baseline wander can cause distortion of important clinical information, particularly ST-segment distortion. The use of digital linear phase high-pass filter minimizes this undesirable effect, but it requires large computational complexity. A multirate architecture with linear phase low-pass filter working at low sampling rate is presented for removal of the baseline wander. Design tradeoff between transition band width and filter delay was considered. We determined the optimal decimation factor with respect to complexity and filter delay. For testing and assessment of behavior of baseline filter we used test signals, normal and wide QRS complexes with different heat rate.