This means that the SA node essentially skips one cycle of sending its own signal.

这窦跳过了放它自己冲动的一个周期。

Normally, an electrical signal starts at the sinoatrial or SA node in the right atrium.

通常，电冲动从位于心的窦开始。

So the sinus node waits the same interval but fires based on the ectopic beat.

接下来窦又等待了同样的间隔时间，该时间内传导的冲动是基于异位心搏出的。

And those fast, leaky cells are found in the sinoatrial node, or the SA node, up in the right atria.

这些快速渗漏的细胞位于窦，或 SA ，位于心上方。

If an atrial cell outside of the SA node initiates a depolarization, it's called an atrial ectopic focus.

如果一个窦以外的心细胞引了一个除极，这个心细胞被称为性异位起搏点。

The starting point of the intrinsic conduction system is the sinoatrial node, or SA node.

内在传导系统的起点是窦。

Notice that each time the SA node fires, it resets all the slower ones, and this is exactly how it works.

注每次窦放电，它就重置了所有更慢的细胞，这就是它工作的原理。

Electrical impulses from the SA node spread throughout both atria and stimulate them to contract.

窦出的电脉冲扩散到整个心并刺激它们收缩。

The gene caused the creation of an exact copy of the sino-atrial node in the heart's upper right chamber.

该基因导致心脏上腔室中窦的精确副本的产生。

In a healthy heart, the sinoatrial node or SA node initiates all electrical impulses in the atria.

在健康的心脏内，窦（SA）产生心内的所有电脉冲。

P wave represents depolarization of the atria initiated by the SA node.

P波代表窦引起的心去极化。

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

比如说，如果窦一起停止工作，那么室就会接任，以一种稍慢的速率。

So let's say the SA node is firing along as usual, but all the sudden an ectopic focus fires one off early.

比方说窦和往常一样放冲动，但是一个异位起搏点提前放冲动阻断了这些冲动的传播。

One important effect of the premature depolarization is that the ectopic focus will depolarize the cells of the SA node, causing the SA node to skip a cycle.

过早除极的一个重要影响就是异位起搏点将会使窦细胞除极，导致窦跳过一个心动周期。

Heart blocks are classified by location where the blockage occurs: - SA nodal block, or SA block – blockage within the SA node.

-窦阻滞，或窦阻滞--窦内的阻滞。

Let's use this bar to visualize the SA node's depolarization rate, which is the fastest, and then each one below is slightly slower.

让我们用这个进度条来表示窦的去极化速率，它是最快的，然后下面的每一条都稍慢一些。

When the atria are full of blood, the SA node fires, electrical signals spread throughout the atria and cause them to depolarize.

心充盈时，窦立即出冲动，电信号会传遍整个心并使其去极化。

In this case, after being depolarized, the sinus node waits its 1 second, and then sends another signal and again we carry on as normal.

在这种情况下，窦在除极之后等待了1秒，然后放另一个信号，心搏得以重新正常进行。

In fact, if something goes wrong with this node, a person might need to have an artificial pacemaker implanted to keep their heart's steady beat.

事实上，如果窦出了问题，个体可能需要植入人工心脏起搏器来保持心脏的稳定跳动。

Now, if we measure out the interval between each SA node fire, we see that it should have fired here, but it doesn't because it was depolarized by the ectopic focus.

这时，如果我们测量每一个窦冲动的间隔，我们可以看到它本应在此处放，但并没有，因为它被异位起搏点除极化了。