Radiofrequency Catheter Ablation of Accessory Atrioventricular Connections

or paroxysmal supraventricular tachycardia involving a concealed accessory AV connection underwent catheter ablation with the use of radiofrequency current. In 179 of the 250 patients, catheter ablation was performed at the time of an initial electrophysiology test. Two hundred thirty-five patients had one accessory AV connection and 15 patients had two or more. One hundred eighty-three accessory AV connections were manifest and 84 were concealed. One hundred sixty-one were located in the free wall of the left ventricle, 47 were in the right free wall, 44 were posteroseptal, 10 were anteroseptal, and five were intermediate septal. The time required for catheter placement, the diagnostic component of the electrophysiology test, and the ablation procedure was recorded for each patient, as was the total duration of fluoroscopy. A follow-up electrophysiology test was performed 2-3 months after the ablation procedure. Ninety-four percent of patients had all accessory AV connections successfully ablated and remained free of symptomatic tachycardia during a mean follow-up of 10±4 months. Two hundred nineteen patients (88%) had all accessory AV connections ablated during the initial attempt at catheter ablation. Mean duration of the entire procedure was 134±75 minutes. Procedure duration was longest in patients with multiple accessory AV connections, shortest in patients with intermediate septal accessory AV connections, and similar in all other locations. A nonfatal complication occurred in nine patients (4%). Conclusions. The results of this study indicate that catheter ablation of accessory AV connections with radiofrequency current can be performed safely and expeditiously in a majority of patients and confirm in a large series the feasibility of catheter ablation at the time of an initial diagnostic electrophysiology test. This abbreviated therapeutic approach avoids the need for electropharmacological testing, long-term antiarrhythmic drug therapy, and surgical therapy in the majority of patients with the Wolff-ParkinsonWhite syndrome or with symptomatic tachycardias involving accessory AV connections. (Circulation 1992;85:1337-1346)