Is the 12-lead electrocardiogram during antidromic circus movement tachycardia helpful in predicting the ablation site in atriofascicular pathways?

Aims: Unlike in the Wolff-Parkinson-White syndrome, there has been no systematic study on the role of the pre-excitation pattern in predicting the ablation site in patients with atriofascicular (AF) pathways. We assessed in a large cohort the value of the 12-lead electrocardiogram (ECG) during antidromic tachycardia (ADT) to predict the site of ablation.

Methods And Results: Forty-five patients were studied, 23 males (51%), mean age of 27 ± 12 years with 46 AF pathways and 48 ADT using the AF pathway for A-V conduction.

Atrial premature beats during decrementally conducting antidromic tachycardia.

Background: Advancement of ventricular activation by an atrial premature beat (APB) given during His bundle refractoriness followed by resetting of an antidromic tachycardia (AT) in patients with decrementally conducting accessory pathway (DAP) is a helpful maneuver to prove pathway existence and participation in the circuit. We aim to assess in a large cohort the role of APB during AT in patients with a DAP.

Methods And Results: Thirty-three patients with a DAP having 34 AT were included in the study: 29 patients had an atriofascicular pathway, 1 had a long atrioventricular DAP, and 4 had a short atrioventricular fiber.