Abstract: Objective〖HTSS〗To assess the left ventricular systolic function in apical hypertrophic cardiomyopathy（AHCM） with three-dimensional speckle tracking imaging(3D-STI).
〖WTHZ〗Methods〖HTSS〗Twenty-one AHCM patients (AHCM group) and 21 healthy volunteers(control group) were selected for routine two-dimensional echocardiography and 3D-STI examination. Three-dimensional dynamic images of left ventricle were obtained and stored, and analyzed by 4D AUTO LVQ software. The parameters and curves of longitudinal strain(LS), circumference strain(CS), area strain(AS) and radial strain(RS) were compared between two groups.
〖WTHZ〗Results〖HTSS〗LVEDV and SV were lower in AHCM group than those in control group(P＜0.05). The values of global LS, CS, AS and RS in AHCM group were all lower than those in the control group(P＜0.01). Compared to the control group, the LS values of anterior wall, lateral wall, posterior wall and posterior interval of the mitral valve level were lower. At papillary muscles level, the LS, AS and RS values of all segment were lower, and the CS values of anterior, anterior wall, lateral wall and  posterior wall interval were lower. All of the strain values of the apex level were lower in AHCM group.The above differences were statistically significant(P＜0.05 or P＜0.01).
〖WTHZ〗Conclusion〖HTSS〗In patients with AHCM, the global systolic function of left ventricular decreased to different degrees, while the segment systolic function of the left ventricular reduced most obviously at the apex level, and the papillary muscle level is also affected. 3D-STI can reflect the variations of left ventricular global and segmental systolic function in AHCM patients.

Key words: cardiomyopathy, hypertrophic, echocardiography, three-dimensional speckle tracking