RADIOFREQUENCY CATHETER ABLATION OF INCES SANT RIGHT ATRIAL REENTRANTTACHYCARDIA WITH A R-P INTERVAL LONGER THAN THE P-R INTERVAL

A case of incessant to permanent supraventricular tachycardia with an R-P interval longer than the P-R interval associated with tachycardiom yopathy is presented. With radiofrequency (RF) current delivered anter ior to the coronary sinus ostium (CSO), the bystander retrograde slow atrioventricular (AV) nodal pathway was ablated at first, enabling to definitely confirm an atrial origin of reentrant tachycardia. Then, RF current delivered inferior to the CSO at the presumed exit from the a rea of slow conduction reproducibly terminated the tachycardia, howeve r, not preventing its reinitiation. Finally, the tachycardia was elimi nated by RF current delivered at the site of earliest and fragmented a ctivity in the low posterolateral right atrium.