Evaluation of left ventricular systolic function and synchrony in patients with essential hypertension by longitudinal strain and peak strain dispersion

Objective To investigate the clinical application value of longitudinal peak strain(LPS) and peak strain dispersion(PSD) in evaluating left ventricular systolic function and synchrony in patients with essential hypertension. Methods Fifty-five patients with essential hypertension were enrolled, including 30 patients with non-left ventricular hypertrophy (NLVH), 25 patients with left ventricular hypertrophy (LVH), at the same time, 30 healthy volunteers were selected as the control group. Echocardiography was performed in all three groups, and two-dimensional dynamic images of the left ventricular apical four-chamber, three-chamber, and two-chamber′s long-axis views were collected for three consecutive cardiac cycles. The myocardial layer-specific strain was used to measure the LPS of the left ventricular myocardium of subendocardium, the middle layer, the subepicardium, and the myocardial strain and the PSD of the whole myocardial layers. Correlation analysis and ROC curve analysis were performed. Results The LPS in the control group, NLVH group and LVH group were decreased in turn from inner to out myocardial layers.Compared with the control group, the LPS in the subendocardial, middle, subepicardial, and whole myocardial layer of NLVH group were decreased (P 0.05). The LPS in the subendocardial, middle, subepicardial, and whole myocardial layer of LVH group were all reduced (P 0.05). Compared with the control group, the PSD of the NLVH group and the LVH group increased (P<0.05). Compared with the NLVH group, the PSD of the LVH group increased (P<0.05). Inter-ventricular septum thickness (IVSd) and the LPS in the subendocardial, middle, subepicardial, and whole myocardial layer were negatively correlated (r=-0.537, -0.518, -0.266, -0.471; all P<0.05), left ventricle posterior wall thickness (LVPWd) and the LPS in the subendocardial, middle, subepicardial, and whole myocardial layer were negatively correlated (r=-0.539, -0.524, -0.283, -0.478; all P<0.05). The area under the ROC curve (AUC) of the LPS in the subendocardial, middle, subepicardial, and whole myocardial layer and PSD for the diagnosis of hypertension were 0.685, 0.652, 0.510, 0.623, 0.995, respectively. The cut-off values were -21.70%, -18.90%, -16.95%, -19.45%, 46.50 ms, and the sensitivities were 94.4%, 83.3%, 77.8%, 94.4%, 100%, respectively, and the specificities were 47.8%, 52.2%, 39.1%, 39.1%, 95.7%, respectively. Conclusions The layer-specific strain can quantitatively evaluate myocardial longitudinal strain in patients with essential hypertension, provide a non-invasive test for early diagnosis of hypertensive heart disease, and the evaluation of left ventricular myocardial stratification. PSD for evaluating primary synchronous changes in left ventricular myocardial contraction in patients with hypertension has certain advantages. Key words: Echocardiography; Hypertension; Ventricular function; Layer-specific strain; Peak strain dispersion