Utility of intracardiac echocardiography during pulsed-field ablation of atrial fibrillation: preliminary experience in large multicenter clinical setting

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. BACKGROUND: Intracardiac echocardiography (ICE) is becoming more common during the ablation of atrial fibrillation (AF) and it may improve procedural effectiveness. However, there is no evidence evaluating efficiency, effectiveness, and safety outcomes of ICE in the context of the novel pulsed-field ablation (PFA) of AF. PURPOSE: We aimed to evaluate the impact of ICE on procedural parameters in consecutive patients (pts) indicated for AF ablation with a new PFA technology. METHODS: All consecutive pts undergoing AF ablation with PFA at 5 experienced centers were included. Protocol-directed PVI was delivered using 2000 V with eight applications per vein, that is, four applications each in the basket and flower poses. Additional lesions were performed at the operator’s discretion. In procedures during which an ICE catheter was used, the ICE catheter was utilized to manipulate the PFA catheter in the left atrium to reach an optimal contact on the atrial structures. At the end of procedures, ICE was utilized for identification of procedure-related complications. Data are reported as median [IQ range]. RESULTS: One-hundred eighty pts were included in this analysis (36[32-40] pts per center; n=124, 69% paroxysmal AF; n=56, 31% persistent AF). The ICE-guided PFA procedures consisted of 35 (19.4%) cases. PVI was achieved in all pts with a 32[32-32.5] PFA applications per pt. Additional applications outside the PVs (i.e. posterior wall ablation) were performed in 31 (17%) cases, requiring 18[12.5-26] PFA deliveries on the lesion sets, all validated through 3D mapping and/or differential pacing. Fluoroscopy time was 17[13-22]min, LA dwell time was 22.5[18.5-27.5]min, skin-to-skin time was 60[52-80]min and total support time (procedural plus patient preparation) was 75[60-90]min. Considering PVI only cases, the use of ICE did not improve procedural metrics (ICE vs no ICE: 23[20-26]min vs 23[19-27]min for the time to PVI, p=0.4141; 65[64-85]min vs 70[60-82]min for support time, p=0.8271; 60[58-60]min vs 60[50-75]min for skin-to-skin time, p=0.8681 and 19[16-23]min vs 15[12-18]min for fluoroscopy time, p=0.0012). On the contrary, when looking at procedures with additional lesion sets, ICE-guided PFA showed some improvements (ICE vs no ICE: 27.5[25-30]min vs 16[13-20]min for the time to PVI, p=0.0003; 75[65-80]min vs 120[90-145]min for support time, p=0.0032; 70[60-74]min vs 82.5[74-112.5]min for skin-to-skin time, p=0.0077 and 20[16.5-22]min vs 20[17-30]min for fluoroscopy time, p=0.3328). No major procedure-related adverse events were reported. CONCLUSION: In our preliminary experience, the use of a novel PFA system for AF ablation was safe and effective. The integration of ICE in guiding ablation, may provide some beneficial aspects, especially in the context of complex AF ablation with additional lesion sets.