S758 Comparative 1-Year Outcomes: Elevated Risk of Cardiac Arrhythmias and Mortality Following Gastric Bypass vs Sleeve Gastrectomy

Introduction: Bariatric surgery significantly improves metabolic health and reduces long-term cardiovascular risk. However, evidence suggests that specific cardiac complications, particularly arrhythmias, may vary between surgical techniques. Gastric bypass induce more profound anatomical and neurohormonal changes than sleeve gastrectomy (SG), potentially influencing cardiac electrophysiology. This study compared the 1-year incidence of cardiac arrhythmias and related outcomes in patients undergoing Gastric bypass versus SG using a large, real-world electronic health record network. Methods: We utilized the TriNetX Global Collaborative Network to conduct a retrospective cohort analysis of patients who underwent gastric bypass (Cohort 1) or sleeve gastrectomy (Cohort 2). Propensity score matching (1:1) was performed using a greedy nearest-neighbor algorithm with a 0.1 caliper. Matching variables included age, sex, race, and comorbidities such as type 2 diabetes, metabolic syndrome, hypertension, obesity, chronic kidney disease, nicotine dependence, and alcohol use. Outcomes assessed over a 1-year period included cardiac arrest, atrial flutter, atrial fibrillation, ventricular tachycardia, ventricular fibrillation, and mortality. Odds ratios (OR) with 95% confidence intervals (CI) were calculated. Results: After matching, each cohort included 81,333 patients. Gastric bypass was associated with higher odds of atrial fibrillation (OR 1.45, 95% CI 1.25–1.68), atrial flutter (OR 1.50, 95% CI 1.15–1.95), ventricular tachycardia (OR 1.54, 95% CI 1.22–1.94), ventricular fibrillation (OR 1.03, 95% CI 0.65–1.63), and cardiac arrest (OR 1.45, 95% CI 1.05–1.99) compared to sleeve gastrectomy. Mortality was also higher in the gastric bypass group (OR 2.29, 95% CI 1.94–2.71). Conclusion: Gastric bypass is associated with increased odds of postoperative cardiac arrhythmias and higher 1-year mortality compared to sleeve gastrectomy. The elevated risk of arrhythmias and cardiac arrest may reflect physiological and metabolic shifts following Gastric bypass, including altered autonomic tone and nutrient absorption. These findings highlight the importance of preoperative cardiac risk assessment and tailored postoperative monitoring in high-risk patients.