Influence of the direction of the atrial wave front on A-V nodal transmission in isolated hearts of rabbits.
Influence of the direction of the atrial wave front on A-V nodal transmission in isolated hearts of rabbits.
复制标题
心房波前方向对兔离体心脏 A-V 结传输的影响。
DOI：
10.1161/01.res.25.4.439
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发表时间：
1969
影响因子：
20.1
通讯作者：
M. Janse
中科院分区：
文献类型：
--
作者：
M. Janse
记录离体兔心脏房室结细胞的跨膜电位，同时通过在终嵴或房间隔上以高、恒定的速率刺激心房来改变心房活动进入房室结的路径。房间隔产生的心房活动向 A-V 结提供的输入效率较低，如 2:1 A-V 传导阻滞的发生所示，与以相同速率在终嵴上行驶期间的 1:1 A-V 传导阻滞相比。大多数房室结细胞动作电位上升的幅度和速率在房间隔驱动过程中较小，并且许多细胞在复极阶段出现较大或较小的“驼峰”，而在刺激终嵴时则不存在这种情况。刺激终嵴期间的房室结兴奋模式与自发性窦性心律期间的类似，但在刺激房间隔期间发生了深刻的改变。结果可以通过假设来自房间隔的心房波阵面异步地激发 A-V 结的心房边缘，导致结内不均匀传导，从而引起纵向分离来解释。结果表明，通过房室结的成功传播至少部分取决于心房波前的方向。该因素可能在心房颤动期间发挥重要作用。
Transmembrane potentials of A-V nodal cells in isolated rabbit hearts were recorded while the route of entry of atrial activity into the A-V node was changed by stimulating the atrium at a high, constant rate on eitherthe crista terminalis or the interatrial septum. Atrial activity arising from the interatrial septum provided a less effective input to the A-V node, as shown by the occurrence of 2 : 1 A-V conduction block, compared to 1 : 1 during driving on the crista terminalis at the same rate. The amplitude and rate of rise of the action potentials of most A-V nodal cells was smaller during driving on the interatrial septum, and many cells developed alarger or smaller "hump" in the repolarization phase, which was absent during stimulation on the crista terminalis. The pattern of A-V nodal excitation during stimulation on the crista terminalis was similar to that during spontaneous sinus rhythm, but was profoundly altered during stimulation on the interatrial septum. The results can be explained by assuming that an atrial wave front coming from the interatrial septum excites the atrial margin of the A-V node asynchronously, resulting in inhoinogeneous conduction within the node, causing longitudinal dissociation. The results show that successful propagation through the A-V node is at least partly determined by the direction of the atrial wave front. This factor may play an important role during atrial fibrillation.