摘要
A canine model of ischemic ventricular tachyarrhythmias was established in open-chest dogs subjected to programmed electrical stimulation (PES) for 5￣8 days after acute myocardial infarction. The electrophysiologic effects of sophoridine (Sop) and procainamide (PA) were observed in this canine model. With routine methods of PES, ventricular tachycardia (VT) and ventricular fibrilation (VF) could be reproducibly initiated in this model. Both drugs distinctly lengthened the QTc interval ( P <0.01) and the effective refractory period (ERP) in normal and ischemic ventricular myocardium ( P <0.01), decreased the dispersion of ERP in ischemic myocardium and the dispersion of ERP in left ventricle (P <0.05), and increased the diastolic excitability threshold of normal and ischemic ventricular myocardium remarkably ( P <0.01). Both drugs effectively prevented the PES-induced VT or VF and ischemia-induced VF ( P <0.05). The results indicated that this canine model is a good and reliable one, sophoridine and procainamide may be effective in preventing the onset of reentrant ventricular tachyarrhythmias after myocardial ischemic damage.
用心脏程控电刺激技术（ＰＥＳ），研究静脉注射槐定对慢性心肌梗塞犬的正常心肌和梗塞心肌的电生理及快速室性心律失常的影响，并与普鲁卡因胺（ＰＡ）对比。研究结果表明，两药均可显著延长ＱＴＣ间期，ＲＥＲＰ、ＮＥＲＰ及ＩＥＲＰ．缩小ＩＤＲ和ＶＤＲ，提高ＤＥＴ，抑制ＰＥＳ诱发的持续性室速和室颤，并能有效地预防心肌梗塞后缺血所致的自发性室颤，证实了槐定有抗缺血性快速室性心律失常的心电生理作用。
