The impact of body mass index for atrial fibrillation ablation; real-world data on outcomes and quality of life
Authors: Vermeer J , Houterman S , Medendorp N M , Van Der Voort P H , Dekker L R C 
Published: October 2024

Abstract

Background
Pulmonary vein isolation (PVI) is a cornerstone in the management of atrial fibrillation (AF). Increasing numbers of overweight and obese patients undergo PVI, despite the association between a higher body mass index (BMI) and adverse ablation outcomes. The risks of perioperative complications and quality of life have hardly been studied for the different bodyweight groups.

Purpose
The purpose of this study is to clarify the impact of BMI on PVI outcomes, including both perioperative complications and change in quality of life after PVI.

Methods
This is an observational, multicentre cohort study of prospectively collected data, covering all 15 ablation centres in the Netherlands. The study included all patients who underwent their first catheter-PVI between January 2015 and December 2021. Patients with a BMI below 18.5 kg/m2, missing BMI data, or prior ablations were excluded. Patients were categorized by BMI; normal weight (BMI 18.5-24.9 kg/m2), overweight (BMI 25-29.9 kg/m2) and obesity (BMI ≥30 kg/m2).
The primary outcome was repeat ablation within one year. A logistic regression model was used to adjust for patient characteristics. A generalized additive model was fitted to visualize the correlation between BMI and the risk of repeat ablation. Secondary outcomes were repeat ablation within 3 years, a composite of the periprocedural complications, and change in quality of life, assessed using the Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) questionnaire before and at one year after PVI.

Results
A total of 20,725 patients (33% female) were included; 72% had a paroxysmal AF pattern. Of all patients, 30% were normal weight, 47% overweight and 23% obese. Within the first year post-index PVI, obese patients had a higher incidence of repeat ablation than normal-weighing and overweight patients (17.8% versus 15.6% and 16.1%, P &lt;0.05). Obesity independently predicted an increased risk of repeat ablation within 1 year (odds ratio 1.15; 95%-confidence interval 1.01-1.31, P =0.03). This increased risk was also apparent for repeat ablations within 3 years (hazards ratio 1.15; 95%-confidence interval 1.06-1.25; P &lt;0.01).
The composite complication rate was 3.8% in normal weighing, 3.0% in overweight, and 4.6% in obese patients, with weight class not being an independent predictor.
All weight groups had a substantial improvement in quality of life one year after ablation. Post PVI, summarized AFEQT score was still lower in obese patients (81), than in normal weight (88; P &lt;0.01) and overweight patients (88; P &lt;0.01).

Conclusions
In a nation-wide contemporary cohort, obesity is an independent predictor for undergoing a repeat ablation within both 1 and 3 years. This relation is not apparent for overweight individuals. Catheter ablation can safely be performed in all weight classes. Despite an overall lower quality of life among obese individuals, substantial improvements in quality of life occur in all weight groups.Visual abstract