biostudies-literatureUnknown6(8)Yamashita S<h4>Background</h4>A new technology, the POLAR cryoballoon system, was designed to enhance maneuvering and stabilizing catheter positions with a softer balloon and more deflectable sheath. These novel characteristics may help achieve successful pulmonary vein (PV) isolation in difficult cases when conventional balloons were used.<h4>Objective</h4>This study aimed to investigate the differences in the lesion profiles, touch-up radiofrequency ablation (RFA) rate, and anatomical predictors of acute PV isolation between the POLAR and Arctic Front Advance Pro (AFA-Pro).<h4>Methods</h4>This retrospective study included 338 consecutive patients who underwent a first cryoballoon ablation for paroxysmal atrial fibrillation at Keio University Hospital from April 2019 to September 2023. Using propensHeart rhythm O21121-1129https://www.ebi.ac.uk/biostudies/studies/S-EPMC12411963biostudies-literatureDifferences between 2 cryoballoon systems in achieving successful pulmonary vein isolation in patients with challenging anatomies.PMC12411963Nishiyama TYamashita SYano SHimeno YKimura TIeda MTakatsuki SYamaoka KIbe SKatsumata YfalseDifferences between 2 cryoballoon systems in achieving successful pulmonary vein isolation in patients with challenging anatomies.<h4>Background</h4>A new technology, the POLAR cryoballoon system, was designed to enhance maneuvering and stabilizing catheter positions with a softer balloon and more deflectable sheath. These novel characteristics may help achieve successful pulmonary vein (PV) isolation in difficult cases when conventional balloons were used.<h4>Objective</h4>This study aimed to investigate the differences in the lesion profiles, touch-up radiofrequency ablation (RFA) rate, and anatomical predictors of acute PV isolation between the POLAR and Arctic Front Advance Pro (AFA-Pro).<h4>Methods</h4>This retrospective study included 338 consecutive patients who underwent a first cryoballoon ablation for paroxysmal atrial fibrillation at Keio University Hospital from April 2019 to September 2023. Using propens2025-01-01T00:00:00Z2025 Aug2026-06-03T07:00:58.886Z2026-05-29T03:05:57.044ZS-EPMC124119634091718510.1016/j.hroo.2025.05.027