Abstract 12868: Normal Values and Reference Ranges for Left Atrial Strain by Speckle Tracking Echocardiography: The Copenhagen City Heart Study

Background: In current literature, left atrial (LA) function assessed by 2D speckle tracking echocardiography (2DSTE) has shown increasing clinical and prognostic significance. We sought to establish age- and sex-based normative values of LA strain measures in the general population and to assess the diagnostic and prognostic yield of the prediction intervals (PI) in relation to baseline and future atrial fibrillation (AF). Methods: We performed 2DSTE in members of the general population included in the 5 th round of the Copenhagen City Heart Study. We determined normative values of peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and left atrial conduit strain (LACS) based on age and sex in 1,757 healthy participants. In a secondary analysis, 3,657 participants, regardless of health status, were included to assess the diagnostic and prognostic value of the established reference values. Results: In the healthy cohort, median age was 46 years (IQR: 33, 57), 62% were female. Median normative values of PALS, PACS, and LACS in the healthy participants were 39.1% (PI: 22.7-67.4%), 15.5% (PI: 6.3-28.0%), and 23.5% (PI: 8.6-44.8%), respectively. We observed higher values and reference limits of PALS and LACS in females compared to males, while no differences were observed for PACS. Across four different age categories, all three LA strain parameters differed significantly in both females and males. PALS and LACS decreased, while PACS increased with advancing age (Figure 1). The lower reference limits of all three LA strain parameters showed high specificity (range 96-98%) in relation to baseline and future AF, implying a low risk of AF in participants with LA strain above the lower prediction interval in their respective sex and age group. Conclusion: We report normal values for LA strain measures stratified by sex and age. The established lower reference limits showed high specificity regarding baseline and future AF diagnosis.