Abstract 13406: Atrial Fibrillation and Atrial Flutter as Predictors of Cardiovascular Outcomes in Patients Hospitalized With Covid-19 Infection

Abstract

Introduction: Patients with atrial structural changes have a higher risk of developing atrial arrhythmias, such as atrial fibrillation (AF) and flutter (AFL), particularly during pro-inflammatory states such as a COVID-19 infection. Amongst these patients, AF/AFL have been found to be markers of disease severity. Our aim was to evaluate AF/AFL as predictors of cardiovascular outcomes, and their synergistic relationship with atrial dilatation, in patients with COVID-19. Methods: We conducted a two-center retrospective study in patients hospitalized with COVID-19 from 2020 to 2021. Atrial enlargement was defined by 2D-guided linear measurement by echocardiography. The primary outcome of interest was to determine the association of MACE, defined as myocardial infarction, non-fatal stroke, cardiac arrest, and/or death, in patients who developed AF/AFL. The secondary outcome was to explore the synergistic risk of atrial enlargement and AF/AFL on MACE. Statistical analyses were performed using SAS 9.4. Results: From 488 patients, 68 (14%) developed AF/AFL. These patients were older (74±11 vs. 64±15 years), had higher rates of hypertension (79% vs. 64%), coronary artery disease (29% vs. 12%), and heart failure (28% vs 10%). There was a significant unadjusted effect of right atrial enlargement (OR 2.12, CI 1.15-3.91) and AF/AFL (OR 1.90, CI 1.14-3.19) on MACE, whereas the effect was not sustained for left atrial enlargement. Multivariable adjusted models showed that AF/AFL and right atrial enlargement had no longer a significant effect on MACE, and only age remained an independent significant predictor (OR 1.27, CI 1.09-1.47). Moreover, there was no joint effect of AF/AFL and right atrial enlargement on MACE when their interaction was accounted for. Conclusion: AF and AFL were not associated with a higher risk of MACE, nor was atrial enlargement shown to modify the relationship between AF/AFL and MACE in patients who were hospitalized with COVID-19. Age remains to be a predictor of poor outcomes. Studies with a larger sample size would be needed to determine if there’s a significant relationship.