一、心脏生理(一)心脏的射血机能1.心动周期与心率心脏一次收缩和舒张,称一个心动周期,包括收缩期和舒张期,通常心动周期是指心室的活动周期而言。如按心率75次/分计算,则每一心动周期平均约为0.8秒。其中心房收缩期约为0.1秒,舒张期约0.7秒;继心房收缩终止,心室进入收缩期,约0.3秒,舒张期0.5秒。 First, cardiac physiology (a) the ejection function of the heart 1. Heart cycle and heart rate Heart contraction and relaxation of the heart, said a cardiac cycle, including systolic and diastolic, usually cardiac cycle refers to the ventricular activity cycle terms. If the heart rate of 75 beats / min, then each heart cycle average of about 0.8 seconds. The atrial systole is about 0.1 seconds, diastolic about 0.7 seconds; following atrial contraction termination, ventricular systolic, about 0.3 seconds, diastolic 0.5 seconds.