His bundle electrograms were recorded and A-V junction pacing was achieved in 30 patients by a pervenous electrode catheter technic. His bundle pacing was achieved in 26, and A-V node pacing in five patients. Conduction time from atrium to the His bundle (A-H time) and His bundle to ventricular activation (H-V time) were measured. During His bundle pacing, the pacing impulse to ventricular acti...

Intra-His bundle block was produced by ligation of the anterior septal artery in dogs. The duration of the His bundle potential was gradually increased following the ligation, and an obvious splitting of the His bundle deflection was observed thereafter. Finally, spontaneous second and/or third degree intra-His bundle block appeared. Before the development of spontaneous block, a pacing induced...

A study correlating the electrocardiographic findings and the histology of the atrioventricular (AV) conduction system was carried out in 14 cases with chronic complete AV block and in 13 cases without chronic complete AV block. Patients with chronic complete AV block were divided into two groups, based on the width of the QRS complex. The QRS complexes were narrow (less than 0.12 second) in fo...

The Purkinje system (PS) and the His bundle have been recently implicated as an important driver of the rapid activation rate after 1-2 minutes of ventricular fibrillation (VF). It is unknown whether activations during VF propagate through the His-Purkinje system to other portions of the the working myocardium (WM). Little is known about restitution characteristic differences between the His bu...

Routes of impulse propagation during reentry in the His-Purkinje system (Re-HPS) in 13 patients were studied using the right ventricular extra stimulus (V2) method and right bundle branch (RBB) recordings in addition to the conventional His (H) bundle recordings. The H-V and RB-V intervals during sinus rhythm averaged 44.2 and 27.6 msec respectively, with the average antegrade H-RB interval 16....