ABSTRACT
Objective:To evaluate the effects of different blood pressure control levels on left ventricular myocardial mechanics in patients with primary elderly hypertension by using two-dimensional speckle tracking imaging (2D-STI).Methods:A total of 315 elderly patients with essential hypertension diagnosed in Bethune Hospital Affiliated to Shanxi Medical University from January to June 2017 were collected and randomly divided into standard antihypertensive group and intensive antihypertensive group. The patients who were receiving antihypertensive drugs were treated with antihypertensive drugs more or less, and the patients who had not yet been treated started antihypertensive drugs therapy. The blood pressure was adjusted to the target value within 3 months (blood pressure in standard antihypertensive group was controlled at 130-150/<90 mmHg, intensive antihypertensive group was controlled at 110-130/<80 mmHg). All patients were followed up for 24 months. After 24 months of antihypertensive drugs treatment, 26 cases of lost follow-up, substandard blood pressure or poor image quality were excluded, and 289 patients were included, standard antihypertensive group ( n=148), intensive antihypertensive group ( n=141) . During the same period, 71 age-matched people without essential hypertension were selected as control group. Comprehensive echocardiography were performed in all subjects at baseline and 24 months. The longitudinal strain of the inner, middle and outer layers (GLS-endo, GLS-mid, GLS-epi) of the whole left ventricle were obtained by two-dimensional speckle tracking technique. The routine echocardiographic and left ventricular strain parameters were compared at baseline and 24 months. Results:①At baseline, the end-diastolic thickness of interventricular septum (IVSD), the end-diastolic thickness of left ventricular posterior wall (LVPWD), the end-diastolic diameter of left ventricle (LVEDD), the left ventricular mass index (LVMI), the relative wall thickness (RWT) and the ratio of early diastolic mitral flow velocity to early diastolic mitral annulus velocity(E/e′) in two antihypertensive groups were higher than those in the control group, and the levels of GLS-endo, GLS-mid and GLS-epi were lower than those in the control group(all P<0.05). There were no significant differences in routine echocardiographic parameters and strain parameters between standard antihypertensive group and intensive antihypertensive group (all P>0.05). ②After 24 months of antihypertensive drugs treatment, LVEDD and E/e′ in standard antihypertensive group and IVSD, LVPWD, LVEDD, LVMI, RWT, E/e′in intensive antihypertensive group were lower than those at baseline, and IVSD, LVMI and RWT in intensive antihypertensive group were lower than those in standard antihypertensive group (all P<0.05). ③After 24 months of antihypertensive drugs treatment, GLS-endo, GLS-mid and GLS-epi in two antihypertensive groups were higher than those at baseline, and GLS-endo, GLS-mid, GLS-epi in intensive antihypertensive group were higher than those in standard antihypertensive group(all P<0.05). Conclusions:①The left ventricular myocardial mechanics is damaged and the systolic function is decreased in elderly patients with essential hypertension; ②The myocardial mechanics is significantly improved after antihypertensive treatment, with more improvement in intensive antihypertensive treatment patients.