胺碘酮对家兔正常和缺血心脏心室复极及复极离散度影响的研究

目的探讨胺碘酮对正常和缺血心脏心室复极及复极离散度的影响，给临床研究提供实验依据。方法采用同步记录心室外膜多个部位单相动作电位的方法，观察家兔正常心脏（正常组）和急性缺血心脏（缺血组）静注胺碘酮前后单相动作电位时程（ＭＡＰＤ９０）和单相动作电位离散度（ＭＡＰＤｄ）的变化。结果正常组用药后左室前壁、左室心尖部和左室侧壁ＭＡＰＤ９０均显著延长（Ｐ均＜０００１），ＭＡＰＤｄ无显著变化（Ｐ＞００５）。缺血组用药后缺血区（左室前壁及左室心尖部）和非缺血区（左室侧壁）ＭＡＰＤ９０均显著延长（Ｐ均＜０００１），但ＭＡＰＤｄ明显减小（Ｐ＜００１）。结论胺碘酮可延长正常和缺血心脏心室复极，对正常心脏复极离散度无影响，但对缺血心脏可使其复极离散度缩小。

EFFECT OF AMIODARONE ON VENTRICULARREPOLARIZATION AND DISPERSION OF VENTRICULARREPOLATIZATION IN NORMAL ANDISCHEMIC RABBIT HEARTS

Objective To investigate the effect of amiodarone on ventricular repolarization and dispersion of ventricular repolarization in the normal and ischemic heatrts to provide an experimental basis for clinical study. Methods Multiple monophasic action potentials (MAP) from epicardium were recorded simultaneously with lead II ECG, the changes of MAP duration (MAPDd) in the normal (normal group) and ischemic (ischemic group) rabbit hearts, before and after intravenous injection of amiodarone, were observed. Results In the normal group,after use of amiodarone,the MAPD90 in anterior wall,apex and lateral wall of left ventricle was significantly lengthened (all P <0001), and there was no significant change in the MAODd ( P >005).In the ischemic group, after use of amiodarone, the MAPD90 in the ischemic area (anterior wall and apex of left ventricle) and non-ischemic area (lateral wall or left but the MAPDd) was significantly decreased (all P <0001), but the MAPDd was significantly decreased ( P <0 01) . Conclusion Amiodarone lengthens ventricular repolarization in normal and ischemic rabbit hearts and has no effect on the dispersion of ventricular repolarization in normal rabbit heart, but shortens the dispersion of ventricular repolarization in ischemic rabbit heart.