Impact of obesity and pattern of atrial fibrillation on long-term outcome following cryoballoon pulmonary vein isolation

Abstract

Abstract Background Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted method for treatment of paroxysmal and persistent atrial fibrillation (PAF, PeAF). Obese and PeAF patients do worse following ablation. However, there are limited data on the impact of both variables on outcomes. Objective To understand the impact of obesity and AF pattern on long-term outcomes following CB PVI. Methods We enrolled consecutive AF patients undergoing CB PVI; all patients had an implantable loop recorder (ILR) for long term continuous monitoring. Obesity (O) was defined as a BMI ≥ 30 kg/m2. The cohort was divided into 4 groups based on presence of obesity and type of AF at the initial ablation: (1) N-O (non-obese) and PAF, (2) O and PAF, (3) N-O and PeAF, and (4) O and PeAF. We assessed long-term AF recurrences, after excluding an initial 3-month post-ablation blanking period. Results The cohort included 322 patients (67 ± 9 years; 209 [65%] male; 177 [55%] PAF; CHA2DS2-VASc 2.7 ± 1.6, 137 [43%] O). Obese patients were younger and more likely to have hypertension and diabetes. During a follow-up of 931 ± 599 days, 211 (66%) patients had recurrent AF. The best outcome was seen in N-O obese patients with PAF; all other groups fared similarly (Figure). Group 1 had significantly lower AF recurrence compared to all 3 other groups (Figure). In multivariate analysis, obesity/AF type was the only significant predictor of AF recurrence (Table). As compared to N-O PAF pts, O PeAF patients had a 2-fold greater likelihood of AF recurrence. Conclusions During almost 3-years of objective follow-up, we found that CB PVI performs best in non-obese pts with PAF. Once obesity occurs, PAF pts respond as poorly to PVI as pts with PeAF, irrespective of obesity status. Additional strategies are needed in these patients.