Left ventricular volumetric conductance catheter for rats.
Left ventricular volumetric conductance catheter for rats.
复制标题
大鼠左心室容积电导导管。
作者：
H. Ito;M. Takaki;H. Yamaguchi;H. Tachibana;H. Suga
左心室 (LV) 容积 (V) 是评估心脏泵功能的重要参数。通过电导导管法原位测量 LVV 已广泛应用于狗和人类，但尚未应用于大鼠等小型实验动物。我们开发了一种用于大鼠左室容积测量的小型化六电极电导导管（3-F）及其信号处理装置。我们比较了在下腔静脉闭塞导致 LVV 逐渐降低期间，通过心尖引入 LV 的电导导管和放置在升主动脉上的电磁流量探头同时测量的每搏输出量 (SV)。通过从六只大鼠中汇集的 SV 进行不同测量，在这些值之间获得了高度线性相关性 (r = 0.982)。在另一组三只大鼠中，用通过心尖引入左心室的 3-F 导管尖端微压计同时测量左心室压力。我们通过逐渐升主动脉闭塞获得收缩末期压力-容积 (P-V) 关系 (Emax) 的斜率。服用普萘洛尔后，Emax 明显降低，而 P-V 关系的体积截距没有变化。电导容量法被证明对大鼠有用。
Left ventricular (LV) volume (V) is an essential parameter for assessment of the cardiac pump function. Measurement of LVV in situ by a conductance catheter method has been widely used in dogs and humans but not yet in small experimental animals such as rats. We instituted a miniaturized six-electrode conductance catheter (3-F) for rat LVV measurement and its signal processing apparatus. We compared stroke volumes (SVs) simultaneously measured with this conductance catheter introduced into the LV through the apex and an electromagnetic flow probe placed on the ascending aorta during gradual decreases in LVV by an inferior vena caval occlusion. A high and linear correlation (r = 0.982) was obtained between these differently measured by SVs pooled from six rats. In another group of three rats, LV pressure was simultaneously measured with a 3-F catheter-tip micromanometer introduced into the LV through the apex. We obtained the slope of the end-systolic pressure-volume (P-V) relationship (Emax) by a gradual ascending aortic occlusion. After administration of propranolol, Emax obviously decreased with no change in volume intercept of the P-V relationship. The conductance volumetry proved to be useful in rats.