Ventriculo-Atrial Conduction Associated with Ventricular Premature Beats

In a group of eight patients with ventricular premature beats, ventriculo-atrial conduction, with retrograde activation of the His bundle and the atria could be demonstrated by His bundle electrograms in four subjects. All had early ventricular premature beats with coupling indices between 210 and 350 msec. In the other four cases, concealed retrograde conduction could be demonstrated in the A-V nodal area. The ventricular ectopic beats were late, and depending upon the refractory period of the A-V node these extrasystoles were interpolated or followed by compensatory pauses.