[The radiofrequency ablation of Mahaim and Kent fibers during the repair of Ebstein's anomaly].

A young man 20 years old was referred to the Institute with Ebstein anomaly. He had experienced palpitations since the age of eight. Those episodes occurred several times a year. During the electrophysiologic study a regular antidromic reciprocating tachycardia was induced using a right atriofascicular connection (Mahaim). The atrial insertion of the Mahaim fibers was in the right posterolateral atrium. Also another orthodromic supraventricular tachycardia was induced with anterograde conduction over atrioventricular node and retrograde conduction over to canceled atrioventricular right posteroseptal bypass tract (Kent). During surgery to repair Ebstein anomaly we decided to perform radiofrequency catheter ablation of both Mahaim and Kent fibers at the tricuspid annulus in the posteroseptal and lateral regions, eliminating accessory pathways conduction. There were no complications during the procedure. The tachycardia has not recur in a six months period of follow up. No antiarrhythmic drugs has been given.