Evaluation of Left Atrial Two-Dimensional Strain in Patients with Systolic Heart Failure using Velocity Vector Imaging

Two-dimensional (2D) Strain is a new reproducible technique for assessing regional myocardial function; however, its application for evaluation of left atrium (LA) function is less studied. We sought to assess LA function in heart failure patients using velocity vector imaging (VVI). Thirty five patients (mean age: 43.34 ± 18.1 years, 59.3% male) with systolic dysfunction [left ventricle ejection fraction (LVEF) < 35%] enrolled. Standard Doppler echocardiography and 2D strain were performed on all subjects. Strain measurements were obtained from apical views. A significant differences in LA volume index (LAVI) and strain were found in patients with systolic heart failure (SHF) versus normal subjects (23.8 ± 4.1 versus 57.8 ± 19.7 ml/m2, P < 0.001 and 39.6 ± 10.6 versus 8.2 ± 5.3%, P < 0.001). Multivariate analysis of separate walls revealed significant inverse relationship between LA size and volume with total and regional (2-ch view) 2D strains of LA. Significant inverse relationship were also detected between pulmonary artery systolic pressure and both total LA strain (22 ± 8 versus 42 ± 10 mmHg, r = -0.4, P < 0.001) and LA strain in 2-chamber (r = -0.5, P < 0.001). A cutoff value of total average LA strain (≥ 23.28%) can differentiate normal and abnormal LA function with a sensitivity of 93% and specificity of 100% and a cutoff value of total LA strain (in average) of 17.2% can differentiate mild and moderate and severe diastolic dysfunction with a sensitivity of 100% and a specificity of 97%. LA strain seems to be a better determinant for diagnosis of abnormal LA function and the degree of diastolic dysfunction in SHF.