在心脏舒张期，心房和心室放松，血液开始流入。

During diastole, the atria and ventricles of your heart relax and begin to fill with blood.

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每一次心脏跳动都包含两个基本部分：舒张期以及方式收缩期。

Each heartbeat has two basic parts: diastole and atrial and ventricular systole.

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因此，随着时间的推移，心脏在收缩和舒张期之间放松所需要的时间越来越长。

So over time, the heart starts to take a bit longer to relax between contractions and fill back up with blood.

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