Spinelli J C, Clavin O E, Cabrera E I, Chatruc M R, Pichel R H, Valentinuzzi M E
Med Prog Technol. 1986;11(1):25-32.
By means of tetrapolar intraventricular impedancimetric measurements and by modifying the aortic impedance with a brief volume unit step afterload increase, with a balloon catheter, we obtained the geometric locus of the end-systolic pressure-admittance points (PES-YES) from the beat to beat pressure-impedance diagram (DPZ), usually three or four beats after inflation. Six experiments in five anesthetized mongrel dogs (average weight 21.6 kg, SD 2.5) were carried out under control conditions and after a slow infusion (4 micrograms/kg/min) of epinephrine to change the myocardial inotropic state. In control, the PES-YES points fell in all cases on a straight line (average correlation 0.968, SD 0.033). After epinephrine, linearity was still good in four experiments (average correlation 0.938, SD 0.059). All animals showed displacements of the regression lines after epinephrine with respect to control. However, the direction of the shifts was not always consistent: three dogs yielded an upward-leftward shift; one showed a crossing point between the two regression lines with an increase in slope after epinephrine; in the remaining two experiments (same dog in different days), the post-epinephrine regression lines of the pressure-admittance end-systolic points were displaced downwards and rightwards. Five out of the six experiments increased the slopes of the lines after infusion of epinephrine.
the method supplied the end-systolic point locus obtained from simple cardiac catheterization and this locus was altered by inotropic intervention.
通过四极心室内阻抗测量，并使用球囊导管短暂增加容量单位阶跃后负荷来改变主动脉阻抗，我们从逐搏压力 - 阻抗图（DPZ）中获得了收缩末期压力 - 导纳点（PES - YES）的几何轨迹，通常在充气后三到四个搏动时获得。在五只麻醉的杂种犬（平均体重21.6 kg，标准差2.5）身上进行了六项实验，分别在对照条件下以及在缓慢输注肾上腺素（4微克/千克/分钟）以改变心肌收缩力状态后进行。在对照情况下，所有病例的PES - YES点都落在一条直线上（平均相关性0.968，标准差0.033）。注射肾上腺素后，四项实验中的线性仍然良好（平均相关性0.938，标准差0.059）。所有动物在注射肾上腺素后相对于对照都显示出回归线的位移。然而，位移方向并不总是一致的：三只狗的回归线向左上方移动；一只狗的两条回归线之间出现交叉点，注射肾上腺素后斜率增加；在其余两项实验中（同一只狗在不同日期），收缩末期压力 - 导纳点的肾上腺素后回归线向下和向右位移。六项实验中有五项在注射肾上腺素后增加了线的斜率。
该方法提供了通过简单的心导管插入术获得的收缩末期点轨迹，并且该轨迹因变力干预而改变。
