Clinical presentation of ventricular-Hisian and ventricular-nodal accessory pathways

Narrow QRS tachycardia or premature beat with bystander atrial activation or ventricular-atrial dissociation is an unusual arrhythmia that can present diagnostic and therapeutic challenges. When ventricular-atrial conduction is robust, these arrhythmias can be difficult to distinguish from atrioventricular nodal reentry.

The purpose of this study was to describe the electrophysiology characteristics, diagnostic maneuvers, and treatment of these types of arrhythmias in a series of 7 cases.

Standard multipolar recording and pacing electrodes were used during electrophysiology studies. Catheter ablation was performed using radiofrequency or cryoenergy.

During electrophysiology studies, ventricular-nodal or ventricular-Hisian conducting pathways were demonstrated to be responsible for the arrhythmias in all 7 cases. Successful ablation of these pathways using radiofrequency energy was accomplished in 6 of the 7 cases.

Ventricular-Hisian and ventricular-nodal associated tachyarrhythmias should be distinguished from typical forms of atrioventricular nodal reentrant tachycardia. Catheter ablation of these pathways can be successfully accomplished using mapping techniques described in our report.