One‐Year Outcomes of Pulmonary Vein Isolation With a Novel Cryoballoon in Asian Population

Background Cryoballoon ablations for pulmonary vein isolation (PVI) to treat atrial fibrillation (AF) are well established. The POLAR SMART study was designed to collect prospective real‐world data on acute and 12‐month safety and effectiveness of the POLARx cryoballoon for de novo PVI. Methods POLAR SMART is a prospective, non‐randomized, multicenter study (NCT05282823) with patients enrolled across 19 centers (Japan and South Korea) and followed up to 12 months. Results AF ablation was performed in 293 patients, 181 receiving only PVI. In the PVI‐only cohort, acute PVI was achieved in 95.0% of patients, and 98.2% of pulmonary veins (PV) with the cryoballoon. Procedure time and fluoroscopy time were 75 ± 25 min and 18.5 ± 11.1 min, respectively. Time to isolation was 42 ± 32 s, with nadir temperature of −56.6 ± 6.9°C. The study met the primary safety endpoint with an event‐free rate of 97.3%. The study effectiveness event‐free rate at 12 months was 75.6% for entire cohort and 81.1% for PVI‐only cohort (POLARx, n = 116; 79.3% and POLARx FIT, n = 65; 84.4%). AF recurrence in PVI‐only cohort was 7.2% for POLARx and 6.2% for POLARx FIT. Ablation procedure increased heart rate (HR) significantly for entire cohort ( p < 0.001). The optimal HR value at predischarge for 12‐month outcome was calculated with 70 bpm (Predicted Probability 0.83). The effect of increased HR remained stable after 12 months for patients ablated with POLARx FIT. Conclusions The POLARx and POLARx FIT cryoballoon systems are safe and effective for PVI in real‐world use. POLARx FIT ablation was associated with a sustained HR increase over 12 months.