Pulmonary vein anatomy and long-term outcome after multi-electrode pulmonary vein isolation with phased radiofrequency energy for paroxysmal atrial fibrillation.

AIMS

We evaluated the effect of pulmonary vein (PV) anatomical characteristics on PV isolation (PVI) and long-term efficacy of ablation with phased radiofrequency (RF) energy and pulmonary vein ablation catheter (PVAC) multi-electrode catheter.

METHODS AND RESULTS

Before the procedure, PV anatomy was visualized by magnetic resonance imaging (MRI). Consecutive patients with paroxysmal atrial fibrillation were treated with the PVAC with successful acute isolation. Follow-up was performed at 3, 6, and 12 months with electrocardiogram and 7-day Holter recording at 6 and/or 12 months. Symptomatic patients received additional event recording. In 110 patients a pre-procedure cardiac MRI was performed. Ninety-seven (88%) had a separate left superior PV and separate left inferior PV, all patients had a separate right superior PV and separate right inferior PV. Fourteen (13%) had a left PV with common trunk and 27 (25%) had a separate right middle PV (RMPV). After a follow-up of 1 year, 57 of 110 (52%) patients were free of AF without anti-arrhythmic drug. No specific anatomical variable that was related to long-term failure could be found. There was a trend for patients with larger veins (>24 mm) or separate RMPV to have a lower efficacy. The number of applications per vein or procedure did not influence long-term outcome.

CONCLUSIONS

In patients who have undergone PVI with phased RF energy and PVAC multi-electrode ablation, long-term efficacy is not significantly affected by PV anatomy or number of applications, although a trend for reduced efficacy is seen for PV with diameter >24 mm, and presence of RMPV.