Feasibility of Two‐Dimensional Global Longitudinal Strain and Strain Rate Imaging for the Assessment of Left Atrial Function: A Study in Subjects with a Low Probability of Cardiovascular Disease and Normal Exercise Capacity

Abstract

Two-dimensional (2D) speckle imaging has shown that it could evaluate not only regional but also global strain (epsilon) and strain rate (SR) of the left and right ventricles. There are no data for global epsilon/SR imaging for left atrial (LA) function evaluation. A total of 54 subjects (37 men; mean age, 44 +/- 10 years) with normal treadmill exercise stress echocardiography and no coronary risk factors were enrolled. Global longitudinal LA epsilon/SR data obtained by 2D speckle imaging with automated software (EchoPAC, GE Medical) were compared with LA volumetric parameters. LA epsilon/SR imaging was acceptable in all patients. Bland-Altman analysis for these parameters showed no evidence of any systematic difference regarding inter- and intraobserver variabilities. Global longitudinal LA strain during systole and peak systolic global longitudinal LA SR were correlated with LA total emptying fraction (EF) (r = 0.399, P = 0.004; r = 0.366, P = 0.008). Global longitudinal LA strain during early diastole and peak early diastolic global longitudinal LA SR were correlated significantly with LA passive EF (r = 0.476, P < 0.001; r = 0.507, P < 0.001). Global longitudinal LA strain during late diastole and peak late diastolic global longitudinal LA SR were not correlated with LA active EF (r = 0.198, P = 0.163; r = 0.265, P = 0.060). Global longitudinal LA epsilon/SR parameters determined by 2D speckle tracking echocardiography are feasible and reproducible indices for the evaluation of LA function.