Weiss J, Stevenson W G
Pacing Clin Electrophysiol. 1984 Jan;7(1):46-50. doi: 10.1111/j.1540-8159.1984.tb04859.x.
A new type of ventriculo-atrial (V-A) gap phenomenon was observed in a patient who underwent a cardiac electrophysiology study and had complete antegrade infranodal A-V block but intact V-A conduction. During ventricular extrastimulus testing, a split retrograde His potential emerged from the ventricular electrogram. As the prematurity of the extrastimulus was increased, the later of the two retrograde His deflections disappeared suddenly at a critical coupling interval and V-A conduction was interrupted. More premature extrastimuli resulted in progressive delay in the His-Purkinje system and delayed appearance of the earlier retrograde His deflection. As a result of this delay, conduction through the His bundle eventually resumed, the second (split) retrograde His reappeared and conduction to the atria resumed. Thus, the initial site of block during the V-A gap phenomenon in this patient was located in the His bundle, with proximal delay occurring in the distal His-Purkinje system. The results indicate that the classic mechanism of gap phenomenon is operative. To our knowledge, this type of V-A gap phenomenon has not been previously described in man.
在一名接受心脏电生理检查的患者中观察到一种新型的室房（V-A）间隙现象，该患者存在完全性顺行性结下房室传导阻滞但室房传导完整。在心室期外刺激测试期间，心室电图中出现了分裂的逆行希氏束电位。随着期外刺激提前程度增加，两个逆行希氏束偏转中较晚出现的那个在一个临界偶联间期突然消失，室房传导中断。更早的期外刺激导致希氏-浦肯野系统逐渐延迟，较早出现的逆行希氏束偏转延迟出现。由于这种延迟，通过希氏束的传导最终恢复，第二个（分裂的）逆行希氏束电位重新出现，心房传导恢复。因此，该患者V-A间隙现象期间的初始阻滞部位位于希氏束，而远端希氏-浦肯野系统出现近端延迟。结果表明间隙现象的经典机制起作用。据我们所知，这种类型的V-A间隙现象此前在人类中尚未有过描述。
