Quantitative comparison of the isolation lesions between conventional- and larger-sized visually guided laser balloon ablation.

Background: The importance of a wider circumferential isolation of the pulmonary veins (PV), which includes a large portion of the left atrial posterior wall (LAPW), has been suggested in several studies. However, the extended isolation area using a larger inflated visually guided laser balloon (VGLB) ablation remains to be elucidated.

Methods: Seventy-eight patients with atrial fibrillation (AF) who underwent VGLB ablation were enrolled in this prospective study. An electroanatomic map of the left atrium was obtained before and after PV isolation (PVI) using a conventional-sized VGLB. The isolation areas were extended by the largest-sized VGLB ablation and remapped in the same manner. After the ablation, isolation areas were calculated with CARTO-3 system. The one-year atrial arrhythmia (Ata) recurrence was assessed.  RESULTS: The largest-sized VGLB ablation yielded statistically greater areas of isolation in left-sided PV antrum (PVA) (11.5 ± 2.3 cm² vs. 15.9 ± 3.5 cm², P < .001) and right-sided PVA (14.2 ± 3.3 cm² vs. 20.6 ± 4.4 cm², P < .001) than the conventional-sized VGLB. Further, non-ablated LAPW (12.3 ± 4.4 cm² vs. 7.8 ± 3.9 cm², P < .001) was significantly reduced after largest-sized VGLB ablation, compared to the conventional-sized VGLB ablation. The one-year Ata freedom was 83.7% in patients with paroxysmal AF and 96.4% in those with persistent AF.

Conclusion: The largest-sized VGLB ablation technique can create a significantly wider isolation area of PVA and debulk a large amount of LAPW than the conventional-sized VGLB ablation. The one-year outcome was similarly high in paroxysmal and persistent AF.