Resumption of dormant accessory pathway conduction with adenosine administration: a simple intervention to ensure successful accessory pathway ablation.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Resumption of dormant accessory pathway conduction with adenosine administration: a simple intervention to ensure successful accessory pathway ablation Asaf Danon, Krishna Kumar Mohanan Nair, and Sheldon M. Singh* Schulich Heart Center, Sunnybrook Health Sciences Center, University of Toronto, A222, 2075 Bayview Avenue, Toronto, ON, Canada M4N 3M5 * Corresponding author. Tel: +1 416 480 6100 ×83659; fax: +1 416 480 6913. E-mail address: [email protected] A 19-year-old man with documented supraventricular tachycardia was referred for a catheter ablation procedure. Atrioventricular reentrant tachycardia utilizing left posteroseptal accessory pathway (AP). After successful radiofrequency ablation, there was no evidence of (AP) conduction during a 1 h waiting period. However, administration of adenosine resulted in transient resumption of the AP conduction. We discuss the mechanism of action and the role of adenosine in unmasking dormant conduction. A 19-year-old with supraventricular tachycardia was referred for an electrophysiology study (EPS). Delta waves were absent on all preprocedural electrocardiograms. The HV interval was 36 ms and ventriculoatrial (VA) conduction non-decremental. Orthodromic atrioventricular reentrant tachycardia utilizing a left-septal accessory pathway (AP) was diagnosed and radiofrequency (RF) energy delivered at