心律平对房室旁道的电生理作用

应用经食道心房调搏方法观察心律平对房室旁道的电生理作用。结果显示：（１）心律平可明显延长房室旁道前向传导的有效不应期（ＥＲＰ）。（２）对心房和房室传导系统ＥＲＰ亦有延长作用。（３）可降低经旁道１：１下传心室率，并可延长经旁道道传时间和心动过速周期长度。（４）９／１２例病人持续性房室折返性心动过这终止发作，并且证实均止于旁道的逆传途径。以上资料表明心律平延长房室旁道ＥＲＰ的作用，是其治疗预激合并快速心律失常的电生理基础

Electrophysiologic Effects of Propsfenone on Atrioventricular Accessory Pathway

Purpose and Methods: Electrophysioloic effects of intravenous propafenone (1.5 mg' kg-1 ) were evaluated by transesophageal atrial pacing in 18 patients with atrioventricular accessory pathway (AP). Results:The results showed that propafenone caused complete antegrade block of AP in five of 7 patients with Wolf-Parkinson-White (WPW) syndrome, and the antegrade effective refractory period (ERP) of AP were lengthened in two of 7 patients. It also prolonged atrial ERP and the ERP of atrioventricular conduction system. It slightly prolonged the retrograde conduction the of AP, and increased the cycle lengths of tachycardia. Nine of 12 sustained atrioventricular reentrant tachycardia were tednatal after the administration of propafenone, and all of 9 cases were terminated at retrograde limb of the reentrant circle. Conclusion: The data suggested that the effect of propafenone in lengthening ERP of AP was the basis of antiarrhythmia in WPW.