Radiofrequency Catheter Ablation of a Mahaim Fiber at Lateral Tricuspid Annulus

Choi, Yun Shik; Lee, Myung Yong; Kim, Hyo Soo; Sohn, Dae Won; Oh, Byung Hee; Lee, Myoung Mook; Park, Young Bae; Seo, Jung Don; Lee, Young Woo; Choi, Young Jin

Abstract

A 20 year-old male with recurrent syncope and wide QRS tachycardea with LBBB type underwent radopfreqiemcu catjeter ab;atopn. Symptoms were present for 8 years. Electrophysiologic study revealed an antidromic atrioventricular reentrant tachycardia using an atrioventricular Mahaim fiber which conducted only anterogradely and resulted in LBBB QRS morphology on preexcitation. ecremental conduction was also noticed during single atrial extrastimulation and rapid atrial pacing. The ateial insertion of thd Mahaim fiber was at the lateral tricuspid annulus and the venteicular insertion was at the lateral right ventricle near the tricuspid annulus. iscrete Mahaim fiber potential was recorded during atrial pacing and during tachycardia. ahaim fiber was successfully ablated at the atrial side of lateral tricuapid annulus where the discrete Mahaim fiber potential was recorded. No complications occurred. Tachycardiadid not recur during a follow-up of 6 months.