One‐Year Clinical Outcomes of Novel Dual‐Sized Cryoballoon Ablation for Atrial Fibrillation

Background Clinical outcomes after atrial fibrillation (AF) ablation using the novel dual‐sized cryoballoon (DS‐CB) are limited. This study aimed to analyze real‐world data on the DS‐CB. Methods This multicenter observational study included consecutive AF patients who underwent pulmonary vein (PV) isolation (PVI) using a DS‐CB catheter (28‐mm/31‐mm). Results In 407 patients (68 ± 11 years, 279 men, 251 paroxysmal AF[PAF]), 1528 (95.9%) out of 1594 targeted PVs were successfully isolated with DS‐CBs. The total application number and application time were 5 [4‐6] and 812 ± 207 s, respectively. Cryoballoon‐related phrenic nerve injury (PNI) occurred in 23 (5.6%) patients, with 4.7% in the right superior PV (RSPV) and 1.0% in the right inferior PV. All but one patient recovered within 12 months. Additional ablation beyond CB‐PVI was performed in 251 (62%) patients. The 1‐year arrhythmia freedom was 91.7% (93.3% for PAF and 89.5% for non‐PAF, p = 0.08), with antiarrhythmic drug use in 23 (9.2%) and 32 (20.6%) PAF and non‐PAF patients, respectively. Forty‐three patients experienced early recurrence of AF (ERAF) within 2 months of follow‐up. In a multivariate Cox regression analysis, including baseline and procedural parameters, a higher nadir balloon temperature in the RSPV (hazard ratio[HR] = 1.076, 95% confidence interval[CI] = 1.024–1.130, p < 0.01) and all 4 PVI with 31‐mm balloons (HR = 3.085, 95% CI = 1.701–5.595, p < 0.01) were significantly associated with arrhythmia recurrence. In the multivariate analysis including all parameters, ERAF (HR = 5.066, 95% CI = 2.928–8.767, p < 0.01) was the strongest predictor of arrhythmia recurrence. Conclusions The 1‐year arrhythmia freedom post‐DS‐CB ablation was 91.7% in real‐world clinical practice; however, right PNI remained a common complication, even with the balloon size adjustability.