Efficacy and safety of intracardiac echocardiography in pulsed-field ablation for atrial fibrillation: initial experience with 3-dimansional intracardiac echocardiography

Use of intracardiac echocardiography(ICE) has shown to be safe and efficacious in radiofrequency ablation of atrial fibrillation(AF). However, the evidence of using ICE in pulsed-field ablation(PFA) for AF is scare. While there is an emerging use of 3-dimansional(3D) ICE in structural heart intervention, the role of 3D-ICE in electrophysiology intervention is not well studied.

To study the role of ICE, in particular 3D-ICE, in a novel PFA system for AF, focusing on procedural metrics (procedural time, fluoroscopy time and number of ablation) and outcomes (acute success and complication).

This was a retrospective single centre study. Patients undergoing AF ablation with PFA were included, patients with concomitant ablation other than pulmonary vein isolation(PVI) +/- posterior wall isolation(PWI) were excluded. PFA was performed with a multi-electrode pentaspline PFA catheter. ICE and 3D mapping system was used at operator’s discrete. PVI was confirmed with entrance block of pulmonary vein by either 3D mapping or pacing. ICE was used to aid transeptal puncture, to assess catheter contact and to monitor for complication such as pericardial effusion.

A total of twenty-three patients were enrolled, with thirteen patients (56%) using ICE during the procedure. 65% patients (n=15) has proximal AF and 35% patient (n=8) has persistent AF. In 91% (n=21) patient, 3D mapping was used. 30% (n=7) patients had PWI done. ICE guided procedure was associated with less fluoroscopic time (ICE vs non-ICE: mean 13min vs 21min, p= .03*) but longer procedural duration (mean 143min vs 91min, p= .015*), there was no different in number of PFA applied (mean 61 vs 61, p = .97). There was no difference in acute success rate (92% vs 100%, p=.38) and complication rate (0% vs 0%, p=1.0). In subgroup analysis comparing 2D and 3D ICE, there was no difference in procedural metrics (2D vs 3D: procedural time 143min vs 147min, p=.7; fluoroscopy time 14min vs 12min, p=.6; number of ablation 67 vs 56, p=.1) in PVI + PWI ablation, however in PVI only ablation there was a trend towards less number of ablations using 3D-ICE (67 vs 50, p=.06) but no difference in procedural time and fluoroscopy time (143min vs 152min, p=.80; 14min vs 11min, p=.57).

Use of ICE in a novel PFA ablation system for AF is safe and can reduce fluoroscopy time for the procedure. In addition, use of 3D-ICE may provide extra benefit in reducing the number of PFA applications in AF ablation, probably due to better contact assessment of catheter. Further studies are needed to delineate the role of 3D-ICE in AF ablation using PFA.

Subgroup analysis for PVI+PWI ablation