Pericardial effusions typically lead to low QRS voltages or electrical alternans, and can be seen on an echocardiograph.

包积液常显示QRS低电压或电交替现象；超声动图也可做出诊断。

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群都会提前出现，意味着一次提前的室收缩。

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通常与QRS主方相反。

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，下传导到室，成一个正常的QRS。

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大于110ms。

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

这就是所谓的P“被阻滞”或QRS群“脱落”。

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

室收缩以QRS复合群的式展现，室复极以及因此发生舒张的，则视为T。

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消失以及QRS复合变宽。

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

因此，QRS群在V1开始时主要为负，在V6时以正性结束。

You just had 5 mLs. House: The QRS is getting wider.

护士: 你刚刚吸了5毫升。豪斯: QRS越来越宽了。

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

QRS的数目总是等于P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复合有4个P。

Absence of P waves and presence of irregular narrow QRS complexes are the hallmark of atrial fibrillation.

无P和不规则窄QRS是房颤动的特征。

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，在单一的律带上产生了不同式的QRS群。

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的第一个偏移是负的，Q就存在。

The number of flutter waves preceding a QRS complex corresponds to number of atrial contractions to one ventricular contraction.

一个QRS群前的房扑的数目，相当于一次室收缩对应的房收缩的数目。

On an ECG, atrial fibrillation is characterized by absence of P-waves and irregular narrow QRS complexes.

在ECG上，房颤动的特征是没有P和不规则的窄QRS群。

The QRS complex represents depolarization of the ventricles which starts with the interventricular septum.

QRS群代表室从室间隔开始的去极化。

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

在电图上，可见PR间期渐进性延长，随后是P，无QRS复合。

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，除极下传导到左束支，然后异常地穿过室，导致一个异常增宽的QRS群。