A New Bodysurface Detection Method for Multibeat Sinoatrial Node Electrogram

This paper presented a new bodysurface detection method for multibeat sinoatrial node electrogram. The idea is to use 40~200 Hz band-pass filter to remove low frequency components of electrocardiogram (ECG) and instrument noise, use amplifier with high common-mode rejection ratio and digital notch filter to remove 50 Hz power-line interference, use optimal wavelet domain Wiener filter to remove electromyogram (EMG) interference, and finally extracts high-resolution microvolt sinoatrial node wave. Clinical trial results have shown that the method has the following advantages: (1) The multibeat sinoatrial node (SAN) electrogram can measure precise sinoatrial conduction time (SACT) directly like the intracardiac SAN electrogram and analyze the dynamic changes of SAN wave in different cardiac cycles. (2) The intracardiac SAN electrogram gives apre-P wave not entirely separated from the atrial A wave, but the multibeat SAN electrogram gets an independent SAN wave. Therefore, the latter is better in the accurate identification of SAN wave. (3) The multibeat SAN electrogram can be detected non-invasively on bodysurface like the time-domain average SAN electrogram, but without the shortcomings of the latter, such as poor synchronous accuracy, low detection rate and unable to do dynamic analysis, etc. (4) The multibeat SAN electrogram needs no shielded room. It is easy to operate, and has low cost and risk. In addition, the detection can be repeated if necessary.