Results of short-term and long-term pulmonary vein isolation for paroxysmal atrial fibrillation using duty-cycled bipolar and unipolar radiofrequency energy.

BACKGROUND: Electrical disconnection of the pulmonary veins (PV) plays an important role in the ablation of paroxysmal atrial fibrillation (AF). Antral ablation using a conventional steerable ablation catheter often is technically challenging and time consuming.

METHODS: Eighty-eight patients (mean age 58 +/- 11 years) with symptomatic paroxysmal AF underwent ablation with a circular mapping/ablation decapolar catheter (PVAC). Ablation was performed in the antral region of the PVs with a power-modulated bipolar/unipolar radiofrequency (RF) generator using 8-10 W delivered simultaneously through 2-10 electrodes, as selected by the operator. Seven-day Holter monitor recordings were performed off antiarrhythmic drugs at 3-, 6-, and 12-month follow-up, and patients were requested to visit the hospital in the event of ongoing palpitations. All follow-up patients were divided into 2 groups: Group 1 with a follow-up of less than 1 year and group 2 patients completing a 1-year follow-up.

RESULTS: Overall, 338 of 339 targeted PVs (99%) were isolated with the PVAC with a mean of 24 +/- 9 RF applications per patient, a mean total procedure time of 125 +/- 28 minutes, and a mean fluoroscopy time of 21 +/- 13 minutes. Freedom from AF off antiarrhythmic drugs was found in 82 and 79% of group 1 and group 2 patients, respectively. No procedure-related complications were observed.

CONCLUSION: PV isolation by duty-cycled unipolar/bipolar RF ablation can be effectively and safely performed with a circular, decapolar catheter. Twelve-month follow-up data compare favorably with early postablation results, indicating stable effects over time.