Abstract WP111: Reduced Left Atrial Strain Is More Common In Embolic Stroke Of Undetermined Source Compared To Non Cardioembolic Stroke

Abstract

Atrial fibrosis, a determinant of atrial cardiopathy, is seen more commonly in ESUS as compared to non-cardioembolic stroke patients and precedes changes in atrial dimension. We utilized speckle tracking echocardiography (STE) to identify atrial cardiopathy and to investigate the association between LA strain and ESUS compared to NCE stroke. Hospitalized patients with ESUS and NCE stroke subtypes who underwent in-hospital STE were included. Three phases of LA strain (reservoir, conduit, and contractile) were retrospectively calculated. Binary logistic regression analyses using LA strain as a continuous variable and as tertiles were performed to determine the association between different phases of LA strain and stroke subtypes (ESUS vs NCE). Among 680 total stroke patients, 355 were classified as NCE and 325 as ESUS. LA reservoir strain (36.3 ± 18.3 vs. 31.5 ± 17.8), LA contractile strain (17.4 ± 11.1 vs. 15.4 ± 10.4), and LA conduit strain (19.0 ± 11.9 vs. 16.7 ± 11.7) differed significantly between NCE and ESUS stroke subtypes. The fully adjusted binary logistic regression revealed that the lowest tertile of LA reservoir (OR 2.378, 95% CI 1.538-3.676), contractile (OR 1.555, 95% CI 1.032-2.342), and conduit strain (OR 2.009, 95% CI 1.293-3.124) was more likely to be associated with ESUS compared to NCE stroke. When using strain as continuous variables, LA reservoir (OR 0.987, 95% CI 0.977-0.997) and conduit strain (OR 0.980, 95% CI 0.965-0.996) were significantly reduced in ESUS compared to NCE. Our study demonstrates that reduced LA strain is more strongly associated with ESUS compared to NCE stroke subtype. We believe that atrial cardiopathy carries mechanistic significance and measuring LA strain may become a critical imaging biomarker in ESUS stroke prognostication.