Abstract TP159: Does Left Atrial Enlargement Predict Outcomes in Acute Ischemic Stroke?

Introduction: Left atrial enlargement (LAE) is a well-established risk factor for atrial cardiopathy, including atrial fibrillation, a common cause of large vessel occlusion leading to ischemic stroke. Previous studies have suggested that left atrial size could correlate with stroke recurrence, infarct size, and stroke-related mortality, and therefore could prove useful in stroke risk prediction. However, findings have been inconsistent. Objective: To determine whether left atrial size is associated with outcome measures -- including modified Rankin score (mRS), mortality, infarct size, and computed tomography angiography (CTA) collateral score -- in patients with acute ischemic stroke (AIS). Design/Methods: In this retrospective, single-center cross sectional study, we chart-reviewed patients admitted with AIS in the period between 2010 and 2023. Inclusion criteria included patients presenting with AIS and either internal carotid artery (ICA) and/or middle cerebral artery (MCA) M1 segment occlusion undergoing CTA within 24 hours from stroke onset. Patients were categorized into two groups – those with enlarged left atria and those without – based on left atrial volume as measured by echocardiography. The 90-day mRS was dichotomized into “good" (less than or equal to 2) and "poor" (2-6). Logistic regression models were used to identify any associations between LAE and the aforementioned outcomes. Results: A total of 153 patients were included in the study, with 62 (41%) meeting criteria for LAE and 91 (59%) without LAE. Multivariable regression analyses revealed no significant correlation between LAE and CTA collateral score (OR=0.72 0.34-4.86), good 90-day mRS (OR 1.87 0.55-6.33), infarct volume (OR=0.68 [0.17-2.72), or overall mortality (OR=1.27 0.45-3.56). Conclusions: In this study of patients presenting with acute ischemic stroke, LAE was not found to be associated with post-stroke outcomes, including 90-day mRS and overall mortality. Despite prior evidence suggesting a potential link between left atrial size and stroke risk, our findings indicate that LAE may not serve as a reliable prognostic marker for post-stroke outcomes in the acute setting. Further research is warranted to explore the role of atrial cardiopathy in long-term stroke recovery and to clarify its prognostic significance across patient subgroups and stroke types.