ventricular presystole

例句：

1. 1. During the ventricular presystole, the heart is preparing for the next contraction.
   在心室舒张期，心脏为下一次收缩做准备。
2. 2. The ventricular presystole is a critical phase in the cardiac cycle.
   心室舒张期是心脏周期中的关键阶段。
3. 3. The ventricular presystole is often used to measure the heart's efficiency during exercise.
   心室舒张期常用于测量心脏在运动时的效率。