Background: How extensive should an appropriate pulmonary vein (PV) ablation be is a matter of controversy. Objective: The study's aim was to investigate the efficacy of minimally extensive PV ablation for isolating the PV antrum (PVA) with the guidance of electrophysiological parameters. Methods: Fifty-five consecutive symptomatic paroxysmal atrial fibrillation (PAF) patients underwent PV mapping with a multielectrode basket catheter (MBC). A 31-mm MBC was deployed in 3-4 PVs as proximally as possible without dislodgement, and the longitudinal PV mapping enabled us to recognize single sharp potentials formed by the total fusion of the PV and left atrial potentials around the PV ostium or the transverse activation patterns that were observed. Those potentials were defined as PVA potentials. Radiofrequency ablation was performed circumferentially targeting PVA potentials with the end point being their elimination. Results: After circumferential PVA ablation, electrical disconnection was achieved in 77% and residual PVA conduction gaps were observed in 23% of all targeted PVs. Those residual conduction gaps were mainly located at the border between ipsilateral PVs (42%) and between the left PVs and left atrial appendage (33%) and were eliminated by a mean of 3 ± 2 minutes of local radiofrequency deliveries. During the follow-up period (11 ± 5 months), 46 (84%) patients were free of symptomatic PAF without any anti-arrhythmic drugs. No PV stenosis or spontaneous left atrial flutter occurred. Conclusions: Electrophysiological PVA ablation with an MBC is feasible and effective for curing PAF because this minimally extensive PVA isolation technique targets the optimal sites, achieving both high efficacy and safety. © 2006 Heart Rhythm Society. All rights reserved.