Modification of the pulmonary vein antrum is associated with recurrence after durable pulmonary vein isolation for paroxysmal atrial fibrillation.

Background: Although previous studies have shown the isolated areas after pulmonary vein isolation (PVI) using cryoballoons (CB) (CB-PVI), no studies have investigated the association between the isolated area and recurrence of atrial fibrillation (AF) and atrial tachycardia (AT). This single-center observational study investigated the association between the ablated area and recurrence rate after durable CB-PVI for paroxysmal AF.

Methods: This study included 76 patients with paroxysmal AF who underwent CB-PVI and established durable PVI with a second procedure, regardless of AF/AT recurrence, 6 months after the first procedure. To compare the ablated zones, we quantified the left- and right-sided PV antral isolation areas and non-ablated posterior wall (PW) area. We examined non-ablated areas of the PW and AF/AT recurrence in the chronic phase.

Results: In total, 16 of the 76 patients had AF/AT recurrence. The mean follow-up duration was 34 months. The non-ablated PW area (14.0 ± 4.6 cm² vs. 11.5 ± 3.7 cm²; p = 0.0213) and the ratio of the non-ablated PW area to the whole PW area (NAPW) (52.9 ± 9.1% vs. 44.8 ± 9.8%; p = 0.003) were significantly higher in the AF/AT recurrence group than in the AF/AT non-recurrence group. NAPW > 50% was an independent predictor of AF/AT recurrence.

Conclusion: The NAPW after durable CB-PVI is associated with AF/AT recurrence. PW isolation or additional applications on the PV antrum with cryoballoon may be considered in addition to PVI in paroxysmal AF, especially in patients with dilated left atria.