Evaluation of Left Atrial Function in Patients with Coronary Artery Disease by Two-Dimensional Strain and Strain Rate Imaging

Background: Left ventricular (LV) dysfunction in patients with coronary artery disease is shown by strain and strain rate imaging. However, left atrium (LA) function in patients with coronary artery disease (CAD) has not been assessed by this method. Methods and Results: In 34 CAD patients, including 17 patients with enlarged LA (LA diameter = 4.0 cm) and 17 with normal-size LA (LA diameter = 4.0 cm), two-dimensional strain echocardiographic imaging (2DSE) was performed. Twenty healthy subjects as a control group were included. Both conventional parameters and strain parameters, such as LA peak systolic strain (LAs S/SR), preatrial contraction strain (LAa S), peak systolic (LAs SR), early diastolic strain rate (LAe SR) and late diastolic strain rate (LAa SR), were measured. Conventional parameters were abnormal in CAD patients with enlarged LA (ELA), but there were no significant differences between CAD with normal-size left atrium (NLA) and control groups. LAs S/SR and LAe SR were lower in patients than in normal controls, and were even lower in CAD-ELA group (P < 0.05). LAa S/SR were lower in CAD patients with ELA (P < 0.05), but without a significant difference between CAD-NLA and control groups. A significant correlation was observed between LAs S/SR and LA emptying fraction (r = 0.85, P < 0.05; r = 0.72, P < 0.05, respectively). LAa S/SR related well to LA ejection fraction (r = 0.68, P < 0.05; r = 0.61, P < 0.05, respectively). LAs SR was most accurate in identifying both CAD patients with NLA from controls and CAD patients from controls (area under the curve: 0.91; 0.95, respectively). Conclusions: LA diastolic dysfunction occurs prior to LA systolic dysfunction in CAD patients, and LAs SR is the most accurate index in identifying patients with CAD. (Echocardiography 2011;28:1095-1103)