Purpose: Magnetically guided irrigated ablation has been introduced for atrial fibrillation (AF) ablation. However, data on ablation of persistent AF is scarce, and first-generation platinum-iridium catheters were burdened by char formation at the catheter tip. Furthermore, energy transmission of these catheters may be suboptimal. Irrigated gold-tip catheters have been introduced to overcome these problems.
Methods: Antral pulmonary vein (PV) isolation (PVAI) was performed using a 5-mm irrigated gold-tip magnetic catheter (power setting, 48 °C maximum, 50 W, 15 s lesion duration; flow-rate, 30 mL/min). The catheter tip was guided by a uniform magnetic field and a motor drive. Left atrial maps were created using an impedance-based left atrial reconstruction and fused with a preprocedural CT or an intraprocedural rotational angiography-based scan.
Results: Fifty-seven patients (42 male, 61.9 ± 8.8 years) underwent PVAI for symptomatic, drug-refractory persistent AF. PVAI was performed successfully in all patients confirmed by entrance block. Procedure time (skin-to-skin) was 214 ± 47 min (104-354 min). Fluoroscopy time was 31 ± 21 min. Ablation time was 4,153 ± 1,350 s. No char or thrombus formation was found at the catheter tip. One pericardial tamponade was observed. Freedom from atrial tachyarrhythmias could be achieved in 57.9 % of the patients included in a follow-up of 11.6 ± 4.2 month. There was a trend to a better outcome in patients without previous attempts of AF ablation (n = 48; 60.4 % vs. 44.4 %, p = 0.47).
Conclusions: Remote magnetic navigation for PVAI seems to be safe and feasible using an irrigated gold-tip catheter. Effectiveness of this novel technique can be confirmed by mid-term outcome.