Novel Technique for Atrial Fibrillation Ablation: Use of Anatomically Designed Pulmonary Vein Ablation Catheter

Abstract

BACKGROUND: Catheter ablation of atrial fibrillation (AF) has been increasingly used in experienced electrophysiology centers. A novel ablation system delivering duty-cycled phased radiofrequency energy via an over-the-wire multipolar circular ablation catheter (PVAC™, Medtronic) to perform linear continuous ablation has been tested for isolation of pulmonary veins (PVs).

Methods: Consecutive patients with indication for AF ablation have been included. Patients underwent PV isolation using the novel ablation system and the PVAC catheter. PV isolation was confirmed by mapping of PV potentials using the PVAC catheter demonstrating entrance and exit block. Success was defined as no AF (no documentation of AF episodes > 30 seconds during 7-day Holter EKG analysis and no symptomatic recurrences after a 3-month blanking period).

Results: 152 patients (35 female) with a mean age of 55 (±12) years were included. 106 patients (70%) had paroxysmal and 46 patients (30%) persistent AF. During the ablation procedure, 594 out of 598 (99%) PVs were effectively isolated during a mean procedure duration of 100 (±26) min and radiation duration of 20 (±8) min. During a median follow-up of 6 months, 65% of paroxysmal patients and 47% of persistent AF patients had no AF documented after a single ablation procedure.

Conclusions: Using a novel duty-cycled phased radiofrequency ablation system is effective and safe in treating AF patients. PV isolation can acutely be achieved in 99% of targeted veins. Mid-term success using a stringent criterion of no AF after a blanking period of 3 months is 65% for paroxysmal and 47% for persistent AF patients using mainly PV-isolation alone.