心脏功能的定量化分析

目的：利用左心室压力容积环（Ｐ－Ｖ环）对心功能进行定量化分析。方法：本文提出了Ｐ－Ｖ环左侧的面积为心室收缩末势能的概念。心室总能量为收缩末势能，搏出功（ｓｔｒｏｋｅｗｏｒｋ）与充盈功之和，其能量效率为搏出功与总能量之比。利用心室造影资料绘制了２９例正常人和１１５例冠心病患者按ＮＹＨＡ分级的各种心功能心室Ｐ－Ｖ环，并分析了心室能量指标。结果：正常心室有最适搏出功，总能量和收缩末势能最低而能量效率最高。随着心功能减退，总能量和收缩末势能增大而搏出功保持稳定，能量效率下降。结论：利用Ｐ－Ｖ环对心室能量分析可对心功能及储备能力进行定量化评估。

Quantitative Analysis of the Cardiac Function

Objective:Analysis of the left ventricular pressure volume loop (P V loop) to assess the ventricular function quantitatively. Methods:The P V loops of 29 normal individuals and 115 coronary heart disease patients with various heart functions by NYHA criteria were constructed by cineangiographic data and the ventricular energies were analysed based on the concept that the left area of the P V loop is the end systolic potential energy of the ventricle.The total ventricular energy is the sum of the end systolic potential energy,stroke work and filling energy,and the energy efficiency is the ratio of stroke work to total energy. Results:The normal ventricle had optimal stroke work,minimal total energy and end systolic potential energy with maximal energy efficiency.Following heart function deterioration,the ventricular total energy and end systolic potential energy were increased,stroke work kept stable and energy efficiency was decreased. Conclusion:Ventricular energy analysis by the P V loop can assess the cardiac function and reserve quantitatively.