Maughan W L, Sunagawa K
Fed Proc. 1984 Jun;43(9):2408-10.
The end-systolic pressure-volume relationship (ESPVR) defines the systolic limits of cardiac performance. Using an isolated cross-circulated canine heart preparation, we examined the influence of afterload impedance changes, changes in coronary artery pressure (CAP), and regional ischemia on the ESPVR. We found that afterload impedance did not change the slope of the ESPVR but that increases in resistance and characteristic impedance did shift the relation slightly to the left. There was no change in the ESPVR with changes in CAP above a certain critical value. A decrease in CAP below this value caused a progressive decline in the slope of the ESPVR. With regional ischemia the ESPVR became nonlinear, and there was a near parallel downward shift of the ESPVR in the high-volume range. This shift was directly proportional to the extent of ischemic area. We conclude that an adequate measurement of the ESPVR demands at least three pressure-volume points to check for linearity and characterization of both the slope and volume intercept.
收缩末期压力-容积关系（ESPVR）定义了心脏功能的收缩极限。我们使用离体交叉循环犬心制备模型，研究了后负荷阻抗变化、冠状动脉压力（CAP）变化以及局部缺血对ESPVR的影响。我们发现，后负荷阻抗并未改变ESPVR的斜率，但阻力和特性阻抗的增加确实使该关系略微向左偏移。当CAP高于某个临界值时，ESPVR不会随其变化而改变。当CAP降至该值以下时，ESPVR的斜率会逐渐下降。在局部缺血情况下，ESPVR变为非线性，并且在高容积范围内ESPVR近乎平行向下偏移。这种偏移与缺血面积的大小成正比。我们得出结论，对ESPVR进行充分测量至少需要三个压力-容积点，以检查其线性以及斜率和容积截距的特征。
