Influence of pulmonary vein ovality on the occlusion efficacy of a size-adjustable cryoballoon: Insights from a 3D silicone model study
Year: 2025
Type: article
Abstract: BACKGROUND: Cryoballoon ablation is an established therapy for atrial fibrillation, but complete pulmonary vein (PV) occlusion can be challenging in large or anatomically complex veins. The size-adjustable cryoballoon (POLARx™ FIT), expandable to 31 mm, was developed to improve occlusion; however, downsizing to a 28-mm balloon is sometimes required. The impact of PV morphology, particularly ovality, on occlusion performance remains unclear. METHODS: In vitro PV models with long-axis diameters of 30 mm and 24 mm were created, each including multiple ovality indices. Occlusion was assessed using 28-mm and 31-mm POLARx™ FIT cryoballoons. Intraluminal PV pressure was measured as an index of occlusion efficacy, with three repeated measurements averaged for each model. RESULTS: For the 31-mm balloon, a significant negative correlation was observed between ovality index and PV pressure in both model sizes (p < 0.0001), indicating reduced occlusion with increasing ovality. No such correlation was observed for the 28-mm balloon. In 24-mm models, the 28-mm balloon achieved higher and more consistent pressures. CONCLUSION: Pre-freeze mechanical occlusion differed according to balloon size and PV geometry. The 31-mm balloon performed best in larger, more circular veins, whereas the 28-mm balloon showed more uniform performance across varying shapes, likely reflecting differences in stiffness and compliance. These findings provide mechanistic insight into balloon-PV interactions and warrant further experimental and clinical validation.
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $550
OpenAlex ID: W7117324737