Miles W M, Chang M S, Heger J J, Rinkenberger R L, Zipes D P, Prystowsky E N
Am Heart J. 1987 Jul;114(1 Pt 1):26-33. doi: 10.1016/0002-8703(87)90302-4.
Three patients with drug-resistant atrioventricular (AV) nodal reentrant tachycardia and two patients with reciprocating tachycardia associated with nodoventricular pathways received oral encainide after a control drug-free electrophysiologic study. In one patient with AV nodal reentry, encainide prolonged anterograde AV nodal conduction, produced complete ventriculoatrial (VA) block, and prevented tachycardia induction. Encainide had no effect on AV or VA conduction in the second patient with AV nodal reentry, and tachycardia with similar cycle length was still induced. The third patient was not studied while receiving encainide, but spontaneous AV nodal reentrant tachycardia occurring multiple times daily was abolished. In both patients with nodoventricular pathways, anterograde AV nodal and VA conduction were prolonged by encainide and tachycardia was no longer inducible. Two patients with AV nodal reentry were given long-term encainide therapy and have been free of recurrent arrhythmias for 16 and 30 months. One patient with a nodoventricular pathway has been without arrhythmia recurrence after 73 months of encainide therapy; the other patient required addition of propranolol to encainide because of recurrent tachycardia. We conclude that encainide can prolong anterograde AV nodal and VA conduction and prevent induced and spontaneous tachycardia in some patients with drug-resistant and highly symptomatic AV nodal or nodoventricular reentry.
三名耐药性房室结折返性心动过速患者和两名与结室旁路相关的折返性心动过速患者在进行了无对照药物的电生理研究后接受了口服恩卡胺治疗。在一名房室结折返患者中，恩卡胺延长了房室结前向传导，产生了完全性室房（VA）阻滞，并预防了心动过速的诱发。恩卡胺对第二名房室结折返患者的房室或室房传导没有影响，仍能诱发类似周期长度的心动过速。第三名患者在接受恩卡胺治疗时未进行研究，但每日多次发生的自发性房室结折返性心动过速被消除。在两名有结室旁路的患者中，恩卡胺延长了房室结前向和室房传导，且不再能诱发心动过速。两名房室结折返患者接受了长期恩卡胺治疗，在16个月和30个月内未再发生心律失常。一名有结室旁路的患者在接受恩卡胺治疗73个月后未再发生心律失常；另一名患者因心动过速复发，在恩卡胺治疗基础上加用了普萘洛尔。我们得出结论，恩卡胺可延长房室结前向和室房传导，并预防一些耐药且症状严重的房室结或结室折返患者的诱发和自发性心动过速。
