Zhou S X, Zhang X M, Wu W, Chen X C
Department of Internal Medicine, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University of Medical Sciences, Guangzhou, China.
Zhongguo Yao Li Xue Bao. 1998 Jul;19(4):363-8.
To study the effects of amiodarone (Ami) on cardiac electrophysiologic properties and ventricular fibrillation threshold (VFT) in right ventricular rapid pacing-induced congestive heart failure (CHF) dogs.
Dogs (n = 25) were randomly allocated into 3 groups: A) control group; B) CHF group induced by right ventricular rapid pacing (4 pulses.s-1) for 4-5 wk; C) CHF models p Ami 300 mg.d-1 for 4-5 wk. The electrophysiologic parameters and VFT were evaluated by electric stimulation and monophasic action potential (MAP) recording.
In CHF models, ventricular MAP duration (MAPD90), ventricular late repolarization duration (VLRD), and intra-ventricular conduction time (IVCT) were prolonged by 43%, 318%, and 19%, respectively; the ratio of ventricular effective refractory period (VERP) to MAPD90 (VERP/ MAPD90) and VFT were decreased by 13% and 48% respectively; the dispersion of ventricular recovery time (RT-D) was increased by 185%. In CHF models, Ami had no effects on ventricular MAPD90, but increased VERP/ MAPD90, IVCT, and VFT by 15%, 10%, and 67%, respectively, shortened VLRD by 87%; and decreased RT-D by 87%. Ami had no significant influences on the hemodynamic parameters of the CHF dogs.
Ami normalizes the cardiac electrophysiologic properties in CHF dogs.
研究胺碘酮（Ami）对右心室快速起搏诱导的充血性心力衰竭（CHF）犬心脏电生理特性及室颤阈值（VFT）的影响。
将25只犬随机分为3组：A）对照组；B）通过右心室快速起搏（4次脉冲·秒⁻¹）诱导4 - 5周的CHF组；C）CHF模型组，给予Ami 300 mg·d⁻¹，持续4 - 5周。通过电刺激和单相动作电位（MAP）记录评估电生理参数和VFT。
在CHF模型中，心室MAP持续时间（MAPD90）、心室晚期复极持续时间（VLRD）和心室内传导时间（IVCT）分别延长43%、318%和19%；心室有效不应期（VERP）与MAPD90的比值（VERP/MAPD90）和VFT分别降低13%和48%；心室恢复时间离散度（RT - D）增加185%。在CHF模型中，Ami对心室MAPD90无影响，但使VERP/MAPD90、IVCT和VFT分别增加15%、10%和67%，使VLRD缩短87%；使RT - D降低87%。Ami对CHF犬的血流动力学参数无显著影响。
Ami可使CHF犬的心脏电生理特性恢复正常。
