The impact of severe obesity on outcomes following cryoballon pulmonary vein isolation

Abstract Introduction Cryoballoon (CB) ablation is a common technique for pulmonary vein isolation (PVI) in patients with symptomatic atrial fibrillation (AF). Obesity is a well-known risk factor for AF and numerous patients undergoing PVI are obese. We aimed to evaluate the effect of severe obesity (BMI ≥35 kg/m2) on atrial arrhytmia recurrence and procedural complications following CB PVI. Methods All patients undergoing de novo CB PVI between January 2021 and October 2023 at a tertiary referral EP center were included in this retrospective analysis. Based on their baseline BMI two patient groups were defined (group A: BMI <35 kg/m2; group B: BMI ≥35 kg/m2); freedom from recurrent atrial arrhytmia within the first year after one PVI procedure and complication rates were compared. Results A total of 404 patients (60.9% male, age 60.8 ±12 years) underwent successful CB PVI. AF was paroxysmal (PAF) in 59.7% of patients, the average BMI was 30 kg/m2. 326 and 78 patients were assigned to group A and B, respectively. Persistent AF (PersAF) was more frequent in group B (38% in group A vs 51% in group B; p=0.028). Median procedure time (55 min vs 54 min; p=0.871) and fluoroscopy time (11 min vs 12 min; p=0.197) were similar in both groups, however cumulative dose was higher in patients with severe obesity (75 mGy vs 176 mGy; p<0.001). Both patient groups had comparable 1-year outcome (67.5% in group A vs 62.8% in group B; p=0.433). PersAF patients without or with severe obesity had similar one year arrhythmia-free survival rates (55.3% vs 57.5%; p=0.806). Procedural complications were numerically higher in group B compared to group A without a statistically significant difference (2.5% vs 3.8%; p=0.497). Conclusion CB ablation in AF patients with severe obesity is safe and effective with an acceptable 1-year atrial arrhytmia recurrence rate.