Objective To explore the value of strain rate imaging in detecting left atrial systolic function in patients with hypertrophic cardiomyopathy (HCM) or hypertensive left ventricular hypertrophy (HLVH).

Methods There were three groups in this study, the group of HCM, HLVH and control, each group had 30 cases. Left atrial diameter, interventricular septal thickness, posterior left ventricle thickness, peak E and A of mitralis were measured by conventional echocardiography. Left atrial fractional shortening (LAFS) was calculated. Tissue velocity imaging of all patients and controls were accepted in apical two, four and long axis chamber views. Strain rate (SR) imaging was performed on all cases, peak atrial systolic left atrial SR (LASRa) were measured at each segment (septal, lateral, posterior, anterior, and inferior walls of left atrium), mean LASRa was calculated by averaging data in all segments.

Results Compared with controls, LAFS and mLASRs of HCM and HLVH were significantly higher (p<0.05). Moreover, LAFS and mLASRs of HCM were significantly higher than HLVH (p<0.05). mLASRa correlated positively with LAFS of HCM and HLVH respectively (r=0.81, 0.88; p<0.01, 0.01).

Conclusions The change of left atrial function of HCM and HLVH presented as pump function increased, especially of HCM, which may take some clinical information to identify these two diseases.