Ablative Instincts in a 22-year-old patient with a delta wave and syncope

Abstract

A 22-year-old male experienced a presyncopal spell while studying for a university examination. The symptoms disappeared within a minute. On assessment in the emergency room, a 12-lead electrocardiogram (ECG) showed a delta wave suggestive of the presence of an accessory pathway (fig. 1). Transthoracic echocardiography was performed and did not detect any structural anomalies. The patient was referred for an electrophysiological study and elective radiofrequency catheter ablation of the accessory pathway (AP). Catheters were placed in the high right atrium (HRA), the His bundle (His), the right ventricular apex (RVA) and the coronary sinus (CS). Baseline cycle length in sinus rhythm, atrial-His (AH) and His-ventricular (HV) intervals were 866, 62 and 10 ms, respectively. Ventriculoatrial conduction was present at baseline with decremental conduction properties on incremental pacing and with the earliest retrograde atrial