It's highest during systole, when the heart contracts to force blood through the arteries.

血压收缩的时候是最高的。当收缩迫使血液通过动脉。

It would squeeze the capsule tightly as the heart contracted and still keep a firm grip on it when the heart was relaxed.

它可以随着的收缩轻微挤压胶囊，且放松时，也能紧紧抓住。

That is reassuring. But what about the other bad beats, the premature contractions in the heart's lower chambers?

这就让人放了。那其有害跳，发生下腔的期前收缩(室性期前收缩)呢?

And what we found was that stimuli that occurred during heart's contraction were perceived to last shorter than stimuli that occurred between the beats, when the heart was relaxed.

们发现，收缩期间发生的刺激持续时间比放松时两次跳之间发生的刺激持续时间短。

On rare occasions, a sudden change in heart rhythm prevents the upper chambers of the heart from contracting normally.

极少数情况下，节律的突然变化会妨碍上腔的正常收缩。

This is a term used to describe the contraction of the heart.

这是一个用来描述收缩的术语。

However because calcium is also involved in cardiac myocyte contraction, these agents also reduce contractility of the heart and should not be used in case of systolic heart failures.

然而，因为钙通道也参与了肌收缩，所以这些药物也会减弱的收缩力，因此收缩性力衰竭患者不应该使用该类药物。

This ability is thanks to the intrinsic conduction system, which is the internal regulating system that causes the heart to contract rhythmically.

这种能力是由于内的传导系统，这是导致有节奏收缩的内部调节系统。

Frank and Starling were looking at the amount of blood in the heart before the ventricles contract.

Frank 和Starling正观察室收缩前的血流量。

This ability is thanks to the intrinsic conduction system, which is defined as the internal regulating system that causes the heart to contract rhythmically.

这种能力归功于内传导系统，内传导系统被定义为使有节奏地收缩的内部调节系统。

That's right - a healthy heart does not pump every last drop of blood out of the ventricles when they contract no matter how strongly they contract.

没错，一个健康的收缩的时候不会把每一滴血从室中泵出，不管收缩的多厉害。

This is the term used to describe the contraction of the heart.

这是用来描述收缩的术语。