Now - in both these situations, the QRS complex comes in early, which means an early ventricular contraction.

现在，在这两种情况下，QRS波群都会提前出现，意味着一次提前的心室收缩。

Also, the ST segment and T wave, which represent repolarization, will often be directed opposite the QRS complex.

同时，代表复极的ST段和T波通常与QRS主波方向相反。

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。

In severe cases, it can also cause a prolonged PR interval, a diminished or absent P wave, and a widened QRS complex.

情况严重时，甚至可以出现PR间期延长、P波消失以及QRS复合波变宽。

People with WPW usually have a PR interval less than 120 ms, and a QRS complex greater than 110 ms.

WPW患者的PR间期常常小于120ms，QRS波大于110ms。

The ventricular contraction is seen as a QRS complex, and the ventricular repolarization, and therefore it's relaxation, is seen as a T-wave.

心室收缩以QRS复合波群的形式展现，心室复极以及因此发生舒张的波形，则视为T波。

As an example, consider how the 6 chest leads - V1 through V6 - register this depolarization wave form called the QRS complex.

作为例子，我们来看一下这6个胸导联，V1-V6是怎样来记录被称为“QRS波群”的除极波形的。

Lead V6 sees the opposite, producing a wide, characteristic " bunny ears" QRS complex with two R waves.

V6导联则相反，产生一个宽的、特征性的“兔耳”QRS波群，两个R波。

In this situation, the depolarization wave conducts down the left bundle branch and then through the ventricles aberrantly, resulting in an abnormally wide QRS complex.

在这种情况下，除极波向下传导到左束支，然后异常地穿过心室，导致一个异常增宽的QRS波群。

This is known as a " blocked" P wave or a " dropped" QRS complex.

这就是所谓的P波“被阻滞”或QRS波群“脱落”。

The number of QRS complexes always equals the number of P waves MINUS one.

QRS波的数目总是等于P波数目-1。

In this example, there are four P waves for every three QRS complexes.

在这个例子中，每3个QRS复合波有4个P波。

Thus, the QRS complex starts as predominantly negative in V1, and ends as predominantly positive in V6.

因此，QRS波群在V1开始时主要为负，在V6时以正性结束。

On an ECG, this is seen as PROGRESSIVE prolongation of PR interval followed by a P wave WITHOUT a QRS complex.

在心电图上，可见PR间期渐进性延长，随后是P波，无QRS复合波。

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。

Alright, so let's say this heart's cruising along at about 60 bpm, which means that there's 1 second between p waves and QRS complexes.

现在让我们假设这个心脏正在以60次/分的心率循环搏动，这表示P波和QRS复合波之间有1秒钟。

As in this example in a lead in which the QRS complex ends with an R wave.

在本例中，QRS波以R波结束。

In majority of cases, the successfully conducted QRS complexes may appear broader than usual.

大多数情况下，成功传导的QRS波群可能较正常宽。

The QRS wave, which is sometimes called the QRS complex, represents the spread of the electrical impulse through the ventricles, or ventricular depolarization.

QRS波，有时被称为QRS波群，代表电脉冲通过心室的传播，或心室去极化。

You will remember from section 1 that a Q wave exists if the first deflection of the QRS complex is negative.

大家可能记得第一部分中，如果QRS波的第一个偏移是负的，Q波就存在。