Inagaki Y, Saito T, Shukuya M
Jpn Circ J. 1979 Mar;43(3):207-13. doi: 10.1253/jcj.43.207.
Changes in ET/PEP in normal subjects are characterized by initial increase associated with the increase in the heart rate, stroke volume and cardiac contractility and are subsequently followed by plateuing or slightly decrease after exceeding the 70% heart rate level of the age predicted maximal heart rate. The decrease in ET/PEP is thought to be mainly due to decrease in stroke volume. After exceeding the predicted maximal heart rate ET/PEP reveals remarkable decrease that may reflect decreased cardiac function (CF). Some patients with ischemic heart diseases revealed decrease of ET/PEP at the heart rate less than the 60% level of the age predicted maximal heart rate. This may indicate decreased cardiac contractility associated with decreased stroke volume (Fig. 10). Since transient left ventricular failure is thought to take place in anginal attack, decreased ET/PEP at the heart rate below the 60% of age predicted maximal heart rate may indicate decreased cardiac function, although invasive evaluation of the cardiac function was not performed in the present study.
正常受试者中，射血时间（ET）与左室射血前期（PEP）的变化特点是，最初随着心率、每搏输出量和心肌收缩力的增加而升高，随后在超过年龄预测最大心率的70%心率水平后趋于平稳或略有下降。ET/PEP的降低被认为主要是由于每搏输出量的减少。超过预测最大心率后，ET/PEP显著降低，这可能反映了心功能（CF）下降。一些缺血性心脏病患者在心率低于年龄预测最大心率的60%时，ET/PEP降低。这可能表明心肌收缩力下降伴每搏输出量减少（图10）。由于认为心绞痛发作时会发生短暂性左心室衰竭，尽管本研究未进行心功能的有创评估，但心率低于年龄预测最大心率的60%时ET/PEP降低可能表明心功能下降。
