Impact of obesity on atrial fibrillation ablation: Patient characteristics, long-term outcomes, and complications.

BACKGROUND: There is an association between obesity and atrial fibrillation (AF). The impact of obesity on AF ablation procedures is unclear. OBJECTIVE: The purpose of this study was to evaluate the influence of body mass index (BMI) on patient characteristics, long-term ablation outcomes, and procedural complications. METHODS: We evaluated 2715 patients undergoing 3742 AF ablation procedures. BMI was ≥30 kg/m2 in 1058 (39%) and ≥40 kg/m2 in 129 (4.8%). Patients were grouped by BMI ranges (<25, 25-<30, 30-<35, 35-<40, and ≥40 kg/m2). RESULTS: As BMI increased from <25 to ≥40 kg/m2, age decreased from 65.3 ± 11.2 to 61.2 ± 9.2 years (P < .001), left atrial size increased from 3.91 ± 0.68 to 4.72 ± 0.62 cm (P < .005), and CHADS2 scores increased from 1.24 ± 1.10 to 1.62 ± 1.09 (P < .001). As BMI increased, paroxysmal AF decreased from 48.0% to 16.3% (P < .0001) and there was an increase in dilated cardiomyopathy (from 7.6% to 12.4%; P < .0001), hypertension (from 41.0% to 72.9%; P < .0001), diabetes (from 4.3% to 23.3%; P < .0001), and sleep apnea (from 7.0% to 46.9%; P < .0001). For the entire cohort, for BMI ≥35 kg/m2 the 5-year ablation freedom from AF decreased from 67%-72% to 57% (P = .036). For paroxysmal AF, when BMI was ≥40 kg/m2 ablation success decreased from 79%-82% to 60% (P = .064), and for persistent AF, when BMI was ≥35 kg/m2 ablation success decreased from 64%-70% to 52%-57% (P = .021). For long-standing AF, there was no impact of BMI on outcomes (P = .624). In multivariate analysis, BMI ≥35 kg/m2 predicted worse outcomes (P = .036). Higher BMI did not impact major complication rates (P = .336). However, when BMI was ≥40 kg/m2, minor (from 2.1% to 4.4%; P = .035) and total (from 3.5% to 6.7%; P = .023) complications increased. CONCLUSION: In patients undergoing AF ablation, increasing BMI is associated with more patient comorbidities and more persistent and long-standing AF. BMI ≥35 kg/m2 adversely impacts ablation outcomes, and BMI ≥40 kg/m2 increases minor complications.

Efficacy of adjunctive ablation of complex fractionated atrial electrograms and pulmonary vein isolation for the treatment of atrial fibrillation: a meta-analysis of randomized controlled trials.

AIMS: Although useful, percutaneous left atrial ablation for pulmonary vein isolation (PVI) does not eliminate atrial fibrillation (AF) in all patients. The ablation of complex fractionated atrial electrograms (CFAEs) has been proposed as an adjunctive strategy to improve the maintenance of sinus rhythm after PVI. Our objective was to analyse the efficacy of adjunctive CFAE ablation. METHODS AND RESULTS: We meta-analysed six randomized controlled trials (total, n=538) using random-effects modelling to compare PVI (n=291) with PVI plus CFAE ablation (PVI+CFAE) (n=237). The primary outcome was freedom from AF or other atrial tachyarrhythmias (ATs) after a single ablation with or without antiarrhythmic drugs. Following a single ablation, PVI+CFAE improved the odds of freedom from any AF/AT compared with PVI alone (odds ratio 2.0, 95% confidence interval 1.04-3.8, P=0.04) at ≥3-month follow-up. There was moderate heterogeneity among trials (I2=63.0%). Complex fractionated atrial electrogram ablation significantly increased mean procedural (178.5±66.9 vs. 331.5±92.6 min, P<0.001), mean fluoroscopy (59.5±22.2 vs. 115.5±35.3 min, P<0.001), and mean radiofrequency (RF) energy application times (46.9±36.6 vs. 74.4±43.0 min, P<0.001). CONCLUSIONS: Pulmonary vein isolation followed by adjunctive CFAE ablation is associated with increased freedom from AF after a single procedure. Adjunctive CFAE ablation increased procedural, fluoroscopy, and RF application times, and the risk/benefit profile of adjunctive CFAE ablation deserves further evaluation with additional studies and longer-term follow-up.