Manuscript Received 28 September 2007; Revised manuscript received 23 October 2007; Accepted for publication 26 October 2007.
A Single Mahaim Fiber Causing Both Antidromic and Orthodromic Reciprocating Tachycardia
Article first published online: 13 DEC 2007
© 2008 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 19, Issue 7, pages 740–742, July 2008
How to Cite
KALBFLEISCH, S., BOWMAN, K. and AUGOSTINI, R. (2008), A Single Mahaim Fiber Causing Both Antidromic and Orthodromic Reciprocating Tachycardia. Journal of Cardiovascular Electrophysiology, 19: 740–742. doi: 10.1111/j.1540-8167.2007.01052.x
- Issue published online: 25 JUL 2008
- Article first published online: 13 DEC 2007
- Mahaim fiber;
- orthodromic tachycardia;
- antidromic tachycardia;
- catheter ablation
We describe the case of a 56-year-old woman referred for electrophysiological (EP) testing for medically refractory supraventricular arrhythmias. During the EP study, the patient was found to have a right free wall atriofasicular (Mahaim type) accessory pathway and an inducible left bundle morphology preexcited tachycardia secondary to antidromic reciprocating tachycardia. The patient also had an inducible narrow complex orthodromic reciprocating tachycardia (ORT). Mapping revealed that the earliest site of retrograde atrial activation during ORT was along the lateral tricuspid annulus. This was the same location where the atriofasicular accessory pathway potential was recorded during sinus rhythm. Radiofrequency ablation at this site eliminated inducibility of both tachycardias and any evidence of antegrade or retrograde accessory pathway conduction. This report describes the case of a very rare right free wall Mahaim type fiber with both antegrade and retrograde conduction capabilities responsible for both antidromic and ORT.