A negative relationship between first-pass pulmonary vein isolation and body mass index in ablation index-guided pulmonary vein isolation

Background We previously reported the relationship between first-pass pulmonary vein isolation (FPI) and pulmonary vein isolation (PVI) durability in ablation index-guided atrial fibrillation ablation. Obesity is a worsening factor for atrial tachyarrhythmia (AT) recurrence. However, the impact of obesity on FPI has been scarcely reported. General anesthesia (GA) facilitates completing PVI by preventing airway obstruction caused by sedative drug use. However, the impact of GA on the relationship also has not been elucidated. Objective The study sought to evaluate the impact of obesity and its relationship with GA on FPI. Methods We retrospectively studied 2187 consecutive patients undergoing ablation index-guided first atrial fibrillation ablation (conscious sedation in 1969 and GA in 218). We divided them into 4 groups according to body mass index (BMI): underweight (BMI < 18.5 kg/m2) (n = 80), normal (18.5 kg/m2 <= BMI < 25 kg/m2) (n = 1,160), overweight (25 kg/m2 <= BMI < 30 kg/m2) (n = 763), and obesity (BMI >= 30 kg/m2) (n = 184). Results FPI rate decreased as BMI increased in both conscious sedation (68.1% in underweight, 61.5% in normal, 48.7% in overweight, and 39.0% in obesity; P < .001) and GA (87.5%, 67.1%, 61.3%, and 44.7%, respectively; P = .01). Multivariate analysis revealed overweight (odds ratio 0.65, 95% confidence interval [CI] 0.53-0.79, P < .001, vs normal) and obesity (OR 0.44, 95% CI 0.31-0.62 P < .001, vs normal) as independent predictors for FPI and obesity as an AT recurrence predictor (hazard ratio 1.35, 95% CI 1.01-1.81, P = .04). Conclusion BMI increase was negatively related to the FPI rate. Notably, the FPI rate in obese patients, even under GA, was low, which might be related to their high AT recurrence.