Abstract WP203: Left Atrial Appendage Morphology is Similar in Embolic Stroke of Undetermined Source and Cardioembolic Stroke and Different From Atherothrombotic Subtypes

Abstract

Background: The left atrial appendage (LAA) is the main source of thrombus in atrial fibrillation (AF), and there is an association between non-chicken wing (NCW) LAA morphology and stroke. We hypothesized that the prevalence of non-chicken wing LAA morphology would be higher among patients with cardioembolic (CE) stroke and embolic stroke of undetermined source (ESUS) than among those with non-cardioembolic stroke (NCS). Methods: This multi-center retrospective study included consecutive patients with ischemic stroke from three comprehensive stroke centers who previously underwent a qualifying chest CT. Patients underwent inpatient diagnostic evaluation for ischemic stroke, and stroke subtype was determined based on ESUS criteria. LAA morphology was determined using clinically performed contrast enhanced thin-slice chest CT by investigators blinded to stroke subtype. The primary predictor was NCW LAA morphology and the outcome was stroke subtype (CE, ESUS, NCS). Results: We identified 172 ischemic stroke patients who had a clinical chest CT performed. Mean age was 70.1±14.3 years and 51.7% were male. Compared to patients with NCS, the prevalence of NCW LAA morphology was higher in patients with CE stroke (58.7% vs. 46.3%, p=0.1) and ESUS (58.8% vs. 46.3%, p=0.2) but this difference did not achieve statistical significance. Conclusion: The prevalence of NCW LAA morphology is similar in patients with ESUS and CE, and may be higher than that in those with NCS. Larger studies are needed to confirm this association.