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

接下来窦房结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发出的。

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

如果一个窦房结以的心房细胞引发了一个除极，这个心房细胞被称为房性异位起搏点。

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

比方说窦房结和往常一样发放冲动，但是一个异位起搏点提前发放冲动阻断了这些冲动的传播。

I'm a registered nurse. I was a patient for the first time during this experience of having an ectopic pregnancy that had burst.

我是注册护士。在这次的经历中，我是第一次当病人。

Unlike pituitary adenomas, ectopic sites of ACTH productions typically don't respond even to high doses of dexamethasone, and the serum cortisol remains high.

和垂体腺瘤不同，异位ACTH综合征一般对高剂量地塞米松没有反应，血清皮质醇还是会很高。

Ectopic beats can also have “triggered activity” which is where cells depolarize early.

异位心搏也有“激发活动”，即在细胞提前除极的位置。

Another type of atrial ectopic focus is a reentrant loop, which is when there’s some tissue that doesn’t depolarize right.

另一类房性异位起搏点是一个折返环路，主要发生在当某些组织不能正确地除极的时候。

Low ACTH levels can be seen in adrenal adenomas and carcinomas, whereas high ACTH levels can be seen in Cushing disease and ectopic ACTH production.

肾上腺腺瘤和肾上腺癌会检测出低水平ACTH，库欣病和异位ACTH综合征会检测出高水平ACTH。

In rare situations, an ectopic focus can trigger atrial fibrillation, which is a more serious arrhythmia where the atria essentially just quiver.

罕见情况下，异位起搏点会引发心房颤动，这是更为严重的心律失常，心房基本上只能颤动（不能正常收缩）。

Alright, so also the location of the ectopic focus in the atria determines how the heart contracts and therefore what the ECG looks like.

并且心房异位起搏点的位置决定了心脏如何收缩以及因此产生的心电图形状。

A ventricular ectopic focus can fire at different points in the cardiac cycle, which we can look at using the ECG.

室性异位起搏点会在心动周期的不同时间点放电，我们可以用心电图监测到。

Next are endometrioid tumors which come from endometrium-like cells which is ectopic, meaning they’re out of place, because those sorts of cells are usually found in the endometrium.

接下来是子内膜样肿瘤，来自出现异位的子内膜样的细胞，意思是它们并没有待在原位，因为那类细胞经常在子内膜上被找到。

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房结细胞除极，导致窦房结跳过一个心动周期。

Also, you might have multiple ectopic foci PVCs, producing different appearing QRS complexes on a single rhythm strip.

同样，你可能有许多室性期前收缩的异位起搏点，在单一的心律带上产生了不同形式的QRS波群。

Nonetheless, the fact that fetuses can develop outside of the uterus has raised serious questions about whether it would be possible for men to have such an ectopic implantation.

尽管如此，胎儿能够在子生长的事实引起许多问题，有关男人可不可能异位妊娠。

Apart from pituitary adenomas, there are ectopic sources of ACTH like small cell lung cancer, and in these cases the excess ACTH is coming from somewhere other than the pituitary.

除了垂体腺瘤，ACTH也有异位来源，比如小细胞肺癌；在这种情况下，垂体以的部位分泌过多的ACTH。

Alternatively, medications such as adrenal steroid inhibitors, like ketoconazole and metyrapone can be helpful - especially for cases of ectopic ACTH production or adrenal carcinomas that have already spread.

另一种方法，像肾上腺类固醇生成抑制剂药物，比如酮康唑和甲吡酮，也会有帮助，尤其是在异位ACTH综合征或已经扩散的肾上腺癌中。

Alright, as a quick recap - A premature atrial contraction is when the atria contract too early because of a depolarization from an ectopic focus.

好，快速总结一下：房性期前收缩是指心房因为来自异位起搏点的除极化而过早地收缩。

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房结冲动的间隔，我们可以看到它本应在此处发放，但并没有，因为它被异位起搏点除极化了。

If an ectopic focus is triggering atrial fibrillation, radiofrequency ablation can be done, which is where radiofrequency waves are used to destroy the tissue that’s causing the ectopic heartbeat.

如果异位起搏点引发了心房颤动，就需要做射频消融了，即利用射频波坏导致异位心搏的组织。