Multivariable Analysis of Associations between LA strain and Atrial Fibrillation Detection in ESUS patients
Among all ESUS patients, in binary logistic analysis using LA strain as tertiles, the lowest tertile of strain values (Tertile 1) showed significant association of LA reservoir strain (unadjusted OR 2.534, 95% CI 1.029-6.236, p = 0.043), LA contractile strain (unadjusted OR 2.828, 95% CI 1.158-6.903, p = 0.022) and LA conduit strain (unadjusted OR 2.614, 95% CI 1.003-6.815, p = 0.049) with AF detection (Table 5). When utilizing LA strain as a continuous variable, decreased LA reservoir strain (unadjusted OR 0.957, 95% CI 0.929-0.987, p = 0.005), LA contractile strain (unadjusted OR 0.949, 95% CI 0.907-0.993, p = 0.025), and LA conduit strain (unadjusted OR 0.952, 95% CI 0.912-0.994, p = 0.025) were significantly associated with detection of AF (Table 5). Findings remain unchanged in the sensitivity analyses adjusting for age. In the sensitivity analysis using only the 155 ESUS patients who received cardiac monitoring, the effect size of LA strain remained stable but significance was lost likely due to small sample size (Supplementary Table 2).