Schlack W, Ebel D, Thämer V
Institut für Klinische Anaesthesiologie, Heinrich-Heine-Universität, Düsseldorf, Germany.
Acta Anaesthesiol Scand. 1996 May;40(5):621-30. doi: 10.1111/j.1399-6576.1996.tb04498.x.
Reperfusion after short coronary occlusion induces regional myocardial dysfunction ("stunning"), including asynchrony of left ventricular (LV) wall motion. Contractile function of stunned myocardium can be increased by inotropic stimulation, but whether this has an influence on wall motion asynchrony is unknown.
In six anaesthetized dogs, the effect of inotropic stimulation on regional myocardial function, and LV asynchrony was tested after the induction of regional stunning (by 15 min of left circumflex artery side branch occlusion). Regional myocardial function was assessed as mean systolic wall thickening velocity (Vswt) by sonomicrometry in the stunned (posterobasal wall) and normal myocardium (anteroapical wall), and LV asynchrony by the phase difference (phi) of the first Fourier transform of the wall thickness signals.
In the stunned myocardium, Vswt decreased from 8.6 +/- 1.0 to 1.7 +/- 1.4 mm s-1 (mean +/- SEM), P < 0.01, and simultaneously phi increased from 10.8 +/- 3.6 to 85.7 +/- 14.3 degrees, P < 0.01. Intracoronary noradrenaline (NADR, 0.25 microgram) improved Vswt (8.3 +/- 1.4 mm s-1, P < 0.01) in the stunned region and changed phi to -38.1 +/- 18.0 degrees, P < 0.05. Systemic NADR (5 micrograms) also increased Vswt of the stunned region (to 3.8 +/- 2.1 mm s-1, P < 0.05), but left phi unchanged (82.9 +/- 19.8 degrees).
Regional function of stunned myocardium can be augmented by inotropic stimulation with noradrenaline, but this does not result in an improvement of LV wall motion asynchrony during systemic inotropic stimulation.
短时间冠状动脉闭塞后的再灌注会诱发局部心肌功能障碍（“顿抑”），包括左心室（LV）壁运动不同步。正性肌力刺激可增强顿抑心肌的收缩功能，但这对壁运动不同步是否有影响尚不清楚。
在6只麻醉犬中，诱导局部顿抑（通过左旋支动脉侧支闭塞15分钟）后，测试正性肌力刺激对局部心肌功能和LV不同步的影响。局部心肌功能通过声测法评估为顿抑心肌（后基底壁）和正常心肌（前心尖壁）的平均收缩期壁增厚速度（Vswt），LV不同步通过壁厚度信号的第一次傅里叶变换的相位差（phi）来评估。
在顿抑心肌中，Vswt从8.6±1.0降至1.7±1.4mm/s（平均值±标准误），P<0.01，同时phi从10.8±3.6增加到85.7±14.3度，P<0.01。冠状动脉内去甲肾上腺素（NADR，0.25μg）改善了顿抑区域的Vswt（8.3±1.4mm/s，P<0.01），并使phi变为-38.1±18.0度，P<0.05。全身应用NADR（5μg）也增加了顿抑区域的Vswt（至3.8±2.1mm/s，P<0.05），但phi未改变（82.9±19.8度）。
去甲肾上腺素的正性肌力刺激可增强顿抑心肌的局部功能，但在全身正性肌力刺激期间，这并不会改善LV壁运动不同步。
