Impact of abdominal obesity on outcomes of catheter ablation in Korean patients with atrial fibrillation

Background Effects of abdominal obesity on outcomes of atrial fibrillation (AF) ablation remains ill-defined. Here, we evaluated the impact of abdominal obesity on the long-term efficacy and safety of catheter AF ablation among Korean patients. Methods We utilized the Korean National Health Insurance Service database to identify patients who underwent AF ablation. Abdominal obesity was defined as waist circumference ≥90cm (males) and ≥85cm (females). The primary endpoint was AF recurrence and secondary endpoints were ischemic stroke, intracranial hemorrhage and death. Additionally, safety endpoints of peri-procedural complications were studied. Results Among 5,397 patients (median age 58 [IQR 51 - 65] years; 23.6% females), abdominal obesity was present in 1,759 (32.6%). The rate of AF recurrence was not statistically different between the groups at 1-year (10.3 vs 8.7 events/100-PYs, p=0.078), though abdominal obesity was associated with significantly higher rates of AF recurrence at 3-year (7.6 vs 6.3 events/100-PYs, p=0.008) and 6-year (6.3 vs 5.2 events/100-PYs, p=0.004) follow-ups. Kaplan-Meier survival analysis found significantly higher rates of AF recurrence in patients with obesity based on body mass index (BMI) and waist circumference (log-rank for trend p=0.006). Using multivariable regression analysis, obesity by both BMI and waist circumference was an independent predictor for AF recurrence (HR 1.21 [95% CI,1.05 - 1.40]), after accounting for other risk factors. There was a trend for increased rates of ischemic stroke at 3-year and 6-year follow-ups in patients with abdominal obesity. Furthermore, this group of patients had a greater rate of intracranial hemorrhage. All-cause death was comparable between both groups. Total peri-procedural complications were not associated with abdominal obesity. Conclusion Abdominal obesity as indicated by waist circumference was associated with a greater burden of concomitant diseases and an independent risk factor for long-term redo AF intervention following catheter ablation but had no effects on total peri-procedural complications.