Abstract
BACKGROUND: A novel size-adjustable cryoballoon can deliver cryotherapy with a 28- or 31-mm balloon size. However, data on antral lesion size with the 31-mm balloon size are scarce. OBJECTIVE: The purpose of this study was to evaluate the antral lesion size of cryoablation with the 31-mm balloon size. METHODS: This prospective single-center study included patients with paroxysmal atrial fibrillation undergoing first-time pulmonary vein isolation (PVI). All pulmonary veins (PVs) were first ablated with the 31-mm balloon size. The 28-mm balloon size was only used as bailout. Pre- and postablation left atrial ultrahigh-definition mapping was performed to assess the antral lesion area. Secondary outcome measures were procedural efficacy including balloon occlusion grade. RESULTS: Complete PVI was achieved in all 80 PVs in 20 patients (mean age 59.7 ± 10.7 years, 75% male). More than one-third of the posterior wall was ablated (35.4% ± 13.8%), and the isolated surface area was 68.7% ± 8.5%. Lateral and septal circumferential antral lesion areas were 12.1 ± 2.0 cm(2) and 19.1 ± 4.7 cm(2), respectively. One patient demonstrated inadvertent overlap of the antral lesions on the roof. There was a trend toward lower complete balloon occlusion in the right superior PV with the 31-mm balloon size in comparison to the 28-mm size (75% and 90%, P = .08). CONCLUSION: Cryoablation with the 31-mm size of a novel size-adjustable cryoballoon results in a large antral lesion. In small atria there is the potential for leaving a small nonablated corridor on the roof when using the 31-mm balloon in both superior PVs, which may be proarrhythmogenic.