犬食管导联和窦房结区及右心房电位同步记录的研究

目的探讨经食管导联信号平均无创性直接地记录窦房结电位(SNP)的技术。方法对8只犬进行了系列的实验研究,直接将双极电极放置于犬的食管导联、窦房结区和右房等部位进行同步记录与信号叠加同步记录;还对窦房结区、右房、左房等部位的局部电活动进行同步记录与观察;当交界心律出现时,再记录上述电位关系的改变。结果食管导联记录的P前波与窦房结区记录的电位同步,并超前于右心房的电位。结论采用信号平均叠加方法经食管导联所记录的P前波确为窦房结电位。

Study of Sinus Node Potentials Based upon Analysis of Electric Activities of Esophagus, Sinus Node Area and Right Atriium in Dogs

Objective To study sinus node potentials recorded by the esophegeal leads. Methods Eight dogs was used in the experiment. The detection system was made by Wuhan General Hospital of Guanzhou Command. The three-channel amplifier was based on an Analog Devices 290 isolation amplifier. The gain of the system was from 200 to 100 000 and the band width was from 0.5 - 1 000Hz. A/D converted to 16-bit accuracy at 2kHz. More than 200 cardiac cycles were averaged. Bipolar X, Y and Z leads served as inputs to the signal averaging system as described below. The X electrode was in the esophagus. The Y electrode was applied to the sinus node area,The Z electrode was in the right atrium. The electric activity of the heart was synchronously recorded from the intraesophageal ,sinus node area and right atrium electrodes by signal averaging method or direct record. When nodular rate took place, the changes in the electric activities could also be recorded. Results 1. The waves recorded by bipolar esophegeal leads were very clear and had good reproduction. 2. The signal of esophegeal lead and sinus node area had the same onset. Conclusions Sinus node potentials can be directly recorded by the signal averaging method of the esophegeal leads.