Increased rates of atrial fibrillation recurrence following pulmonary vein isolation in overweight and obese patients

Abstract

Introduction: Catheter ablation is common for patients with symptomatic, drug-refractory atrial fibrillation (AF). Obesity is a known risk factor for incident AF. The impact of obesity on AF ablation outcomes is incompletely understood. We sought to determine the impact of elevated body mass index (BMI) on pulmonary vein isolation (PVI) procedural outcomes and associated complications.

Methods and results: We evaluated patients undergoing PVI from 2001 to 2015, dividing them into four groups: normal weight (BMI ≥ 18.5 to < 25), overweight (BMI ≥ 25 to < 30), obese (BMI > 30 to < 40), and morbidly obese (BMI ≥ 40). Demographic and procedural characteristics, complications, and ablation outcomes were compared among groups. A total of 701 patients (146 time-matched controls, 227 overweight, 244 obese, and 84 morbidly obese) with complete demographic, procedural, and follow-up data were included. Increasing BMI correlated positively with HTN, OSA, CHA₂ DS₂ -VASC score, and persistent AF (P ≤ 0.001 for all associations). Radiofrequency application time and intraprocedural heparin dose increased with BMI (P ≤ 0.001). Arrhythmia recurrence at 1 year was 39.9% in controls, while higher in all high-BMI groups (overweight, 51.3%; obese, 57%; morbidly obese, 58.1 %; P = 0.007 for all versus controls). Impact of BMI on AF recurrence was not seen in persistent AF patients. Complication rates across groups were similar.

Conclusions: AF recurrence after catheter ablation is higher in overweight, obese, and morbidly obese patients comparing to normal-weight controls, driven primarily by outcomes differences in paroxysmal AF patients. Complications were not associated with increased BMI.

Keywords: atrial fibrillation; body mass index; catheter ablation; obesity.