Treatment and conversion of drug-resistant atrial flutter with radiofrequency energy

Drug-resistant atrial flutter (AF) is a clinical problem mainly when it is associated with fast ventricular rate or severe heart disease. Endocardial mapping of AF can identify the critical slow conduction area of the reentrant circuit; localized intervention in this area with radiofrequency (RF) energy could modify AF. Eight pts (mean age 56 ± 13 years) were referred for extremely symptomatic, recurrent AF which was resistant to antiarrhythmic drugs (1A, 1C, Sotalol, Amiodarone) used in combination. In 1 pt type I AF was present, in 6 pts type I and II AF was observed, in 1 pt the type was not identifiable. We delivered several RF impulses (10-25 W for 5-10 sec) to the area of slow conduction by means of the distal electrode of a 4-polar lead used in unipolar configuration. In 7 pts RF terminated AF within 24 hours after the procedure without any complication. During the follow-up (range 4-15 months), 6 pts had not AF recurrences; in 1 pt AF resumed 13 months later, in 1 pt stable atrial fibrillation developed, all of them were symptom-free. Three pts were on antiarrhythmic drugs (2 on Amiodarone for ventricular arrhythmias, 1 on Amiodarone and Sotalol for episodes of non sustained atrial fibrillation). We suggest that localized ablation of slow conduction area of the reentrant circuit may have a role in the treatment of drug-resistant AF without the need for nodal ablation and permanent pacemaker.