One-year follow-up after irrigated multi-electrode radiofrequency ablation of persistent atrial fibrillation

Irrigated multi-electrode ablation (IMEA) is a novel tool to perform pulmonary vein isolation (PVI). The aim was to compare IMEA with point-by-point radiofrequency (RF) ablation in patients with persistent atrial fibrillation (AF) undergoing PVI.

Forty-nine patients (age 60 ± 9 years, 82% male) were studied. 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. Validation of PVI based on the IMEA catheter was performed using a standard circular mapping catheter. Ninety-two of 94 pulmonary veins (PVs) (98%) were isolated using IMEA alone. 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). Of 94 PVs presumed to be isolated after IMEA ablation, validation using a standard circular mapping catheter showed persistent PV potentials in 33 PVs (35%), requiring additional IMEA ablation. 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).

With similar total procedure duration, IMEA-PVI was associated with shorter net ablation time and longer fluoroscopy time. 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.