Impact of Atrial Fibrillation Diagnosis-to-Ablation Time on 24-Month Efficacy and Safety Outcomes in the Cryo Global Registry

Abstract Background and aims Early rhythm-control therapy in atrial fibrillation (AF) results in higher freedom from atrial arrhythmia (AA) recurrence and improved cardiovascular outcomes. The optimal timing of Cryoballoon ablation (CBA) is unknown. Methods We evaluated AA recurrence and procedure-related complications of early vs. late CBA (≤12 vs. >12 months from diagnosis) in patients enrolled in the prospective Cryo Global Registry (121 centers in 37 countries, NCT02752737). Results A total of 3447 subjects were followed through 12 months and 1220 through 24 months. In summary, 1573 patients (46%) had early ablation at a median [IQR] of 0.3 [0.1–0.6] years from AF diagnosis (age 62±12 yrs., 35.8% female, 71.4% paroxysmal), and 1874 (54%) had late ablation at a median of 3.4 [1.9–6.7] years after diagnosis (age 61±11 yrs., 36.2% female, 75.0% paroxysmal). Early ablation patients were less hypertensive (53.5% vs. 57.9%, p=0.01), less symptomatic (1.5±1.1 vs. 1.8±1.1 symptoms/patient, p<0.01), and had smaller left atrial diameters (41±7mm vs. 42±7mm, p<0.01). Freedom from AA recurrence was 81.5% (95% CI: 78.7–83.9%) in the early vs. 71.7% (95% CI: 68.9–74.3%) in the late ablation group at 24 months (p<0.01). The risk of cardioversion was 41% lower in the early ablation group (HRAdj: 0.59 (0.42–0.83), p<0.01). Serious procedure-related adverse events occurred in 2.4% and 3.5% of patients in the early and late ablation groups (p=0.045), respectively. Conclusions CBA within 12 months from AF diagnosis resulted in higher freedom from AA recurrence and is associated with fewer safety events in a real-world evaluation. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT02752737