Balloon-in-basket vs integrated pentaspline vs variable-loop circular pulse field ablation catheter for atrial fibrillation ablation head to head

Introduction

Pulsed-field ablation (PFA) is comparable in safety, feasibility, and efficacy to thermal energy for atrial fibrillation (AF). Three platforms embody distinct architectures and pulse deliveries. VARIPULSE (Biosense Webster) is a variable-loop circular catheter (VLCC) delivering bipolar microsecond pulses (3x1.8 kV) across ten ring electrodes; loop diameter adapts to pulmonary vein (PV) size. FARAWAVE (Boston Scientific) is a pentaspline multielectrode catheter (four electrodes per spline) applying biphasic microsecond pulse trains (1.8-2.0 kV per 2.5s) in basket/flower pose with rotational stacking for antral coverage. VOLT (Abbott) is a single-use balloon-in-basket catheter whose eight nitinol splines serve for mapping, pacing, and PFA delivery (1.345-1.7 kV). All three catheter use impedance-based proximity for contact visualization ad magnetic-sensor electroanatomic mapping (EAM) integration. Direct head-to-head comparisons remain limited.

PURPOUSE: To compare feasibility, safety and efficacy across VLCC, Pentaspline and Balloon catheter.

Methods

We analysed consecutive AF ablations using VLCC (n=121), Pentaspline (n=115) or Balloon (n=40). End points: procedure, fluoroscopy and left-atrial (LA) times, number of PFA applications (per-vein/overall), first-pass isolation (FPI), intra-procedural AF termination, and acute safety. Mid-term efficacy (≥6-month) was assessed as AF-free survival.

Results

Baseline features were broadly balanced (table 1), but persistent AF was more frequent in Pentaspline cohort than in the VLCC and balloon (p<0.05). VLCC had the shortest fluoroscopy and procedural time; the balloon catheter had the shortest LA dwell time (p<0.05). Applications per PV were highest with VLCC (15/vein), intermediate with pentaspline (8), and lowest with Balloon (4); yielding overall deliveries of 54 [33–66], 53.7±10.6, and 14.5 [9.5–17.75] respectively. First pass isolation (FPI): VLCC 87%, Pentaspline 94%, Balloon 87.5% (p<0.05). In patient with ≥ 6 month follow-up, AF free survival did not differ (p=0.988): VLCC 91.3%, Pentaspline 81.8%, Balloon 81.3%. One major complication (transient ST-segment elevation) occurred with the balloon catheter resolved after nitrates infusion.

Conclusions

Catheter architecture and pulse-delivery strategy translated into distinct procedural profiles with broadly comparable acute and mid-term effectiveness. The balloon-in-basket system required the fewest applications and had the shortest LA dwell time, consistent with a single-shot workflow. The pentaspline system combined high FPI with more frequent intra-procedural AF termination but longer times, reflecting a higher prevalence of persistent AF and PVI+ strategies. The VLCC also achieved high FPI but required more applications, consistent with integrated-mapping, multipoint ring-electrode approach. Safety was favourable across systems, with only one transient coronary event reported.Clinical and Echo Characteristics