Demonstration of retrograde conduction over an atriofascicular accessory pathway.

INTRODUCTION

Absence of retrograde conduction over a right atriofascicular accessory pathway causing reciprocating tachycardia has been considered a hallmark of this clinical entity.

METHODS AND RESULTS

This report describes successful catheter ablation in a patient presenting with the distinctive pattern of preexcited left bundle branch block tachycardia utilizing a right atriofascicular accessory pathway. This pathway, however, exhibited the unique capability of ventriculoatrial conduction. Both anterograde and retrograde conduction were characterized by "node-like" properties.

CONCLUSION

Demonstration of retrograde accessory pathway conduction in this particular setting does not exclude the diagnosis of a single, atriofascicular accessory pathway.