Abstract 12793: Atrial Arrhythmias in the Young and Syncope: Insights From the Nationwide Readmissions Database

Abstract

Introduction: Atrial fibrillation and atrial flutter are two of the most common cardiac arrhythmias in the general population, and have been recognized in patients who present with syncope. Atrial arrhythmias could be a marker for autonomic dysfunction, especially in the younger population. Large database studies investigating the impact of atrial fibrillation and atrial flutter on patients with syncope are lacking. This study aims to utilize the Nationwide Readmissions Database (NRD) to analyze patients admitted with syncope and to compare readmission rates among those with versus without atrial arrhythmias. Methods: We queried the 2018 NRD for admissions with a primary diagnosis of syncope in patients aged 18 or older. Admissions were grouped into two cohorts: the atrial fibrillation/atrial flutter (AFF) cohort and the non-AFF cohort. Propensity score matching was used to balance the two groups. The cohorts were analyzed over a 6-month follow-up period using readmission for syncope as the primary outcome. A multivariate cox-regression model was utilized to examine the association between atrial arrhythmias and readmission for syncope. Results: 7,986 non-AFF index admissions were matched to 8,046 AFF index admissions. Overall, readmission rates between non-AFF and AFF cohorts were similar (2.2% vs 2.1%, p = 0.75), however, young patients (60 or younger) in the AFF cohort had a higher readmission rate than young patients in the non-AFF cohort (6.4% vs 3.2%, p = 0.04). There was a statistically significant interaction between age and atrial arrhythmias; patients aged 60 or younger with atrial arrhythmias were twice as likely to be readmitted for syncope over the 6-month follow-up period (HR: 2.09 (1.07 - 4.09), p = 0.03). Conclusions: Increased risk of re-admission for syncope in the younger population with AFF could be an indicator of autonomic dysfunction and warrants further exploration for potential treatments that address this common mechanism.