First, if the AV node is receptive, it gets conducted down to the ventricles, resulting in a normal QRS complex.

首先，如果房室结接受它，它将向下传导到心室，形成一个正常的QRS波。

If, for example, the SA node stopped altogether, then the AV node would take over at it's slightly slower pace.

比如说，如果窦房结一起停止工作，那么房室结就会接任，以一种稍慢的速率。

When that depolarization wave from an atrial ectopic focus gets to the AV node, there are a couple options.

当除极波从房性异位起搏点到达房室结，它有许多选择可做。

This empty space here is called the PR segment, and it corresponds to the pause in the AV node.

这里的时间间隔叫做PR间期，它相当于房室结处的延搁。

So from the AV node, the signal travels straight down to the inferior end of the heart and gets distributed to both sides.

所以从房室结，信号直接传播到心脏的下端，并被分布到两侧。

Another scenario, though, is if a depolarization wave from an atrial ectopic focus gets through the AV node but get sent through the ventricles abnormally like when a bundle branch is in refractory.

另一种情况，如果从房性异位起搏点来的除极波通过了房室结，但却在一个异常的时间到达心室，比如当一个束支处于不应期。

Now in a normal electrical conduction system, the AV node is the only place where the signal can get through from the atria to the ventricles.

在一个正常的电传导系统中，房室结是心房向心室传导的唯一通路。

Also, the closer the ectopic focus is to the AV node, the shorter the PR interval, which is the time from the P wave to the QRS complex.

并且，异位起搏点越靠近房室结，PR间期就越短，也就是P波到QRS复合波群的时间。

On an electrocardiogram, the P-wave corresponds to atrial contraction, the PR interval corresponds to the slight delay through the AV node, and the QRS complex is ventricular contraction.

在心电图里，P波表示心房收缩，PR间期表示房室结的延搁，QRS波代表心室的收缩。

Now, when the signal hits the AV node, it actually gets delayed for like, a tenth of a second — so the atria can finish contracting before the ventricles contract.

现在，当信号到达房室节点时，它实际上会延迟十分之一秒——所以心房可以在心室收缩之前完成收缩。

The impulses leap across synapse-like connections between the cells called gap junctions, and continue down the conduction system until they reach the atrioventricular node, or AV node, located just above the tricuspid valve.

这些脉冲跨越细胞之间称为间隙连接的突触状连接，并沿着传导系统继续前进，直到它们到达位于三尖瓣正上方的房室结或房室结。

This treatment essentially uses cautery to cut and destroy the pathway, essentially boarding off the secret back door, leaving behind only one connection between the atria and the ventricles, the AV node.

这种治疗手段主要是通过烧灼来切断和破坏旁路，最终封闭这些秘密的后门，只留下一条心房通往心室的道路，即房室结。

Now, the interesting thing is that in addition to the pacemaker cells in the SA node, cells in the AV node, Bundle of His, and the Purkinje fibers, all have the ability to generate an electrical potential.

好了，有趣的是除窦房结起搏细胞以外，房室结、希氏束以及浦肯野纤维中的细胞都有形成电势的能力。

It's then delayed just slightly as it goes through the atrioventricular or AV node, before it passes through the Bundle of His and to the Purkinje fibers of the left and right ventricles, causing them to contract as well.

之后，它在通过房室结时发生了短暂的延搁，而后通过房室束以及左右室的浦肯野纤维，使左右心室收缩。