Abstract Body (Do not enter title and authors here): Background: Obesity is associated with increased in-hospital complications in patients with atrial fibrillation and atrial flutter (AF/AFL). The effects of weight loss intervention through bariatric surgery remain controversial, as it has been reported to increase in-hospital mortality in AF/AFL patients but also shown to reduce AF recurrence after ablation. However, its impact on short-term outcomes in AF/AFL patients undergoing ablation remains unclear.
Hypothesis: Pre-ablation weight loss via bariatric surgery reduces in-hospital complications in AF/AFL patients afterablation.
Methods: Data from the National Inpatient Sample (2016-2022) were used. Patients with a primary diagnosis of AF/AFL who underwent catheter ablation were included, while those with body mass index (BMI) < 30 kg/m² were excluded. Eligible patients were categorized into 4 groups based on BMI or bariatric surgery status: 1) Class I obesity(N=2,450), 2) Class II obesity (N=2,430), 3) Class III obesity (N=3,740), and 4) Pre-ablation weight loss (N=527). Demographics and in-hospital outcomes were analyzed. Multivariable analysis was performed with adjustment for age, sex, race, and comorbidities.
Results: Our results showed that class I obesity patients were the oldest (66±11 years), while class III obesity patients were the youngest (61±11 years); the mean age in the weight loss group was 64±10 years. Most patients in the overweight and obese groups were male, whereas females predominated in the weight loss group (p<0.01). Patients in the weight loss group had fewer comorbidities than those with obesity (p < 0.01). The weight loss group had significantly shorter hospital length of stay (LOS) (p<0.01; β-coefficient [95%CI]: -0.44 [-0.79, -0.09], -1.01 [-1.45, -0.57] vs. classesII–III obesity, respectively) and lower incidence of acute kidney injury (p<0.01 vs. classes II–III obesity), acute respiratory syndrome and infection (p<0.01 vs. class III obesity). The incidence of cardiac/pericardial complications and hemorrhage/hematoma were comparable across groups. In-hospital outcomes did not differ between patients in the weight loss group and those with class I obesity (Figure 1).
Conclusion: Pre-ablation weight loss through bariatric surgery was associated with short-term benefits in AF/AFLpatients after catheter ablation, including reduced in-hospital LOS and complications, particularly among those with Class III obesity, and may help prevent long-term adverse outcomes.