Extent of posterior wall lesion following pulmonary vein isolation with pentaspline pulsed field and cryoballoon ablation: the potential role of deployment technique

Background Pulmonary vein isolation (PVI) using cryoballoon (CB) or pulsed field ablation (PFA) with a pentaspline catheter achieves similar efficacy in atrial fibrillation (AF), but lesion extension on the left atrial posterior wall (LAPW) may differ. Pentaspline-PFA (P-PFA) has been reported to create broader LAPW lesions, potentially leaving narrow viable corridors that have been hypothesized to be proarrhythmic. Objective To descriptively compare the extent of chronic unintended left atrial posterior wall isolation after PVI with P-PFA and CB ablation. Methods We conducted a single-center ambispective study including consecutive patients undergoing repeat left atrial mapping after index PVI with either P-PFA, using a protocol designed to ensure catheter alignment with the pulmonary veins, or CB. Patients with additional LA ablation between index procedure and remapping, unrelated LAPW scarring, or posterior pulmonary vein gaps were excluded. The primary endpoint was isolated LAPW area. Secondary endpoints included percentage of isolated LAPW and minimum residual corridor width. Results Seventy-four patients were included in the analysis: 49 P-PFA and 25 CB. Mean age was 64.2 ± 10.0 years, 64.9% were male, and 55.4% had persistent AF. Isolated LAPW area was 8.3 ± 4.0 cm 2 in the P-PFA group and 9.5 ± 3.9 cm 2 in the CB group, with no statistically significant difference detected between groups (mean difference −1.26 cm 2 , 95% CI: −3.22 to 0.70; p = 0.203). The percentage of isolated LAPW area was 39.9 ± 17.6% vs. 38.9 ± 14.9% ( p = 0.805), and minimum residual corridor width was 19.7 ± 9.9 vs. 18.6 ± 11.0 mm ( p = 0.671), respectively. P-PFA was associated with shorter procedure time (44.2 ± 10.2 vs. 65.8 ± 24.6 min; p < 0.001), shorter LA dwell time (38.1 ± 9.6 vs. 60.6 ± 20.5 min; p < 0.001), lower fluoroscopy time (5.3 ± 3.9 vs. 13.0 ± 9.7 min; p < 0.001), and lower dose–area product [5.3 (2.8–9.7) vs. 19.3 (6.5–31.0) Gy·cm 2 ; p < 0.001]. Conclusion In this descriptive, hypothesis-generating study, no statistically significant difference in chronic LAPW isolation extent was detected between P-PFA and CB ablation. These findings support the hypothesis that catheter deployment technique may influence posterior wall lesion geometry, warranting confirmation in adequately powered prospective studies.