Evaluation of left ventricular systolic function in different layers myocardium in patients with hypertrophic cardiomyopathy by two-dimensional speckle tracking echocardiography

Abstract

Objective To assess the systolic function in left ventricular subendocardial myocardium, midmyocardium and subepicardial myocardium in patients with hypertrophic cardiomyopathy (HCM) by two-dimensional speckle tracking echocardiography. Methods A total of 32 patients with HCM and 32 healthy adults were included in the study. All standard measurements were obtained from the left ventricular short-axis views at the levels of mitral annulus, papillary muscle and apex, and apical four-chamber, two-chamber, and long-axis views. Two-dimensional speckle tracking imaging was employed. The global peak systolic radial strain, peak systolic longitudinal strain and circumferential strain of each layer of the left ventricle were measured. Results In patients with HCM and the control group, the peak systolic longitudinal strain and circumferential strain reduced from subendocardial myocardium to subepicardial myocardium. The global peak systolic radial strain in patients with HCM was significant lower than that in the control group. And in patients with HCM, peak systolic longitudinal strain in subendocardial myocardium, midmyocardium and subepicardial myocardium was significant lower than those in the control group. Conclusions Peak systolic longitudinal strain and circumferential strain are reduced from subendocardial myocardium to subepicardial myocardium.Myocardial systolic function is impaired in patients with HCM. In patients with HCM, longitudinal strain of each layer is lower, but circumferential strain is mainly reduced in midmyocardium and subepicardial myocardium compared with that in the control group. Key words: Echocardiography; Cardiomyopathy, hypertrophic; Ventricular function, left; Two-dimensional speckle tracking imaging