Comparison of irrigated multi-electrode radiofrequency ablation and point-by-point ablation for pulmonary vein isolation in patients with persistent atrial fibrillation with persistent atrial fibrillation

Atrial fibrillation is the most common supraventricular arrhythmia in the general population. It is related to increased morbidity and mortality and reduced quality of life. Pulmonary vein isolation has emerged and today remains the cornerstone of atrial fibrillation ablation. There are multiple different tools and technologies used to achieve pulmonary vein isolation, and irrigated multi-electrode ablation was a novel tool to perform pulmonary vein isolation. It has been evaluated in patients with paroxysmal atrial fibrillation; however there is no data on use of this technology in patients with persistent atrial fibrillation. The aim of our study was to compare irrigated multi-electrode ablation with point-by-point radiofrequency (RF) ablation in patients with persistent atrial fibrillation under-going PVI. In this prospective study, we included forty-nine patients (age 60 + 9 years, 82% male). In 24 patients, the IMEA catheter was used in conjunction with an electroanatomic mapping system. Twenty-five patients undergoing RF point-by-point ablation (RF-PVI) served as a control group. Patients were followed for 12 months with 24 Holter ECG monitoring at 3, 6, and 9 months and 7 days Holter ECG at 12 months follow up. Results have confirmed our hypothesis that procedural parameters are similar between irrigated multielectrode ablation and standard point-by-point radiofrequency ablation. Procedure time was 125 + 23 min in the IMEA group and 127 + 31 min in the RF-PVI group (P = 0.79). Fluoroscopy time was 12.2 (11 – 16.1) min with IMEA compared with 5.2 (4.1 – 9.3) min in the RF-PVI group (P, 0.001). Net ablation time was 11.8 (10.2 – 15.4) min in the IMEA group compared with 33.6 (30.3 – 40.1) min in the RF-PVI group (P, 0.001). However, cumulative ablation times were significantly longer in the IMEA group compared to RF PVI group. Although complication rates were low in our study, longer cumulative ablation times could have implications on complication rates, which needs to be verified in future studies. Success rates, defined as freedom from any atrial fibrillation at 12 months were similar between the two groups. At 12 months, 16 of 24 patients (67%) in the IMEA group compared with 17 of 25 patients (68%) in RF-PVI group were free from AF (P. 0.99). In conclusion, IMEA-PVI was associated with shorter net ablation time and longer fluoroscopy time with similar procedure duration. Irrigated multi-electrode ablation recordings were not sufficient to confirm isolation in 35% of PVs. Single procedure efficacy after 12 months was similar between the two groups