The ability of cardiac pump function is mainly decided by the amount of cardiac work and its clinical significance is obvious. The pump per stroke work of heart can given by the increase in blood pressure and the kinetic energy of the ejection blood. With the changing left ventricular pressure during the period, accurate calculation of ventricular stroke work is very difficult. There have many difficult in measurement of cardiac output and assessment of ventricular blood pressure is very convenient if insert conduit. This paper analyzes the ability of left ventricular ejection, summed up the traditional analysis of left ventricular ejection ability, and presents a dynamic simulation model to estimate the left ventricle of left ventricular Micro-Surface doing work to analyze the amount of left ventricular function which is based on the theory of elastic cavity.