Fasciculoventricular accessory pathway: A misleading and unusual bypass tract

Abstract

We present the case of a 25 year-old man referred for an electrophysiological study due to suspected pre-excitation as the cause of two recent syncopal episodes. The admission electrocardiogram (ECG) showed a borderline PR interval of 120 ms and apparently small delta waves visible in leads V2-V4. Intracardiac recordings showed a short HV interval of 18 ms that was stable despite decremental atrioventricular conduction. A fasciculoventricular accessory pathway was diagnosed. Administration of ajmaline normalized ECG and HV interval. We discuss electrocardiographical features of this rare bypass tract.
(Cardiol J 2010; 17, 1: 83-87)