评价心室肌收缩力的参数—Emax及其方法

Emax-a Parameter for Evaluating Left ventricular Contractility

通过理论分析发现心室收缩期的最大张力、心室收缩末期压力和每搏心输出量三者之间存在着相互关系，从而获得一种新的简便的评价心室肌收缩力的方法—心室收缩末期容积—压力相关直线斜率（Ｅｍａｘ）。用１２条狗进行实验验证，测得的Ｅｍａｘ值（０．６０±０．１７ｋＰａ／ｍｌ）与复杂方法测得的值相接近；而且重复性好，能非常敏感地反映出心肌收缩力的变化。结果表明，采用这种方法来评价心肌缺血时的心室肌收缩功能，比其他血流动力学参数更有效。因此，本方法是一种有效的评价心室肌收缩力的方法。

After making theoretical analysis,the relationship among the maximal tension of ventricularcontraction, left ventricular end-systolic pressure and stroke volume was found and then.a new andsimple method for evaluating left ventricular contractility,the slope of the left ventricular end-systolicpressure-volume relation(Emax) was found.12 male mongrel dogs were used to test this method,theresults show that the value of Emax 0.60 ± 0.17 kPa/ml obtained from this simple method is veryclose to the value got from complicated method;it has good repetition and is very sensitive to the varia-tion of myocardial contraction.Using the method to evaluate left ventricular contraction after ischemia,we found Emax is more effective than other hemodynamic parameters.