Le Heuzey J Y, Moutet J P, Guize L, Olmos A, Cabanis C, Maurice P, Péronneau P
Arch Mal Coeur Vaiss. 1984 Feb;77(2):146-54.
Strips of isolated atrium were obtained from 10 rabbits to study the validity of indirect methods of estimating sinoatrial conduction time during variations of the sinus rhythm. Direct recordings of the trans-membrane action potential of the sinus node were made. Mapping of the sinus region was undertaken to determine the site of the dominant pacemaker. A quadripolar surface electrode was positioned on the lower part of the crista terminalis for stimulation and recording of the atrial potential. This enabled a comparison to be made between the indirect estimated and the directly measured conduction times. An intrasinusal shift of the dominant pacemaker was obtained by cooling from 38 degrees C to 35 degrees C. This shift occurs progressively in the cranino-candal direction. The estimated and measured conduction times were compared under basal conditions and after cooling. The sinus cycle was significantly longer (p less than 0.001) at 35 degrees C (318 +/- 68 ms) than at 38 degrees C (255 +/- 48 ms). The mean measured anterograde conduction time also decreased from 36 to 31 ms (p less than 0.01) and the mean measured retrograde conduction time also decreased from 39 to 33 ms (p less than 0.02); the total conduction time decreased from 75 to 64 ms (p less than 0.001). The results of the total estimated conduction times were discordant. The associated effects of stimulation and cooling can cause conduction defects and an overestimation of the conduction time.(ABSTRACT TRUNCATED AT 250 WORDS)
从10只兔子身上获取离体心房条带，以研究在窦性心律变化期间估计窦房传导时间的间接方法的有效性。对窦房结的跨膜动作电位进行了直接记录。对窦房区域进行标测以确定主导起搏点的位置。将四极表面电极置于界嵴下部用于刺激和记录心房电位。这使得能够对间接估计的传导时间和直接测量的传导时间进行比较。通过从38℃冷却至35℃获得主导起搏点的窦内移位。这种移位在头尾方向上逐渐发生。在基础条件下和冷却后比较估计和测量的传导时间。35℃时（318±68毫秒）的窦性周期明显长于38℃时（255±48毫秒）（p<0.001）。平均测量的前向传导时间也从36毫秒降至31毫秒（p<0.01），平均测量的逆向传导时间也从39毫秒降至33毫秒（p<0.02）；总传导时间从75毫秒降至64毫秒（p<0.001）。总估计传导时间的结果不一致。刺激和冷却的相关效应可导致传导缺陷并高估传导时间。（摘要截短于250字）
