OBJECTIVETo evaluate the effect of blood pressure on vascular endothelial function using echo-tracking (ET) technology.

METHODSThirty hypertensive (HP) patients, 30 subjects with high normal blood pressure (HN), and 30 normotensive control (NC) subjects were enrolled in this study. For each subject, conventional two-dimensional ultrasound was performed to measure the intima-media thickness (IMT), and an ET system was utilized to assess the carotid elasticity (Ep, β, AC, AI, and PWVβ).

RESULTSAs the blood pressure increased, IMT, Ep, β, AI, and PWVβ values all increased and AC value decreased. Before excluding the confounding factors, the difference in IMT, Ep, β, AC, AI, and PWVβ values were significant between the 3 groups. After excluding the confounding factors, only PWVβ value was significantly different between HN group and NC group; but between HP and NC group and between HP and HN group, the other parameters still showed significant differences. Systolic blood pressure had significant influences on IMT, Ep, AC, AI, and PWVβ values, diastolic blood pressure significantly affected AI value, and pulse pressure significantly affected Ep and β values.

CONCLUSIONHigh normal blood pressure has no obvious effects on vascular function, and blood pressure is an independent risk factor of vascular endothelial dysfunction only in the stage of early hypertention. In early atherosclerosis, systolic blood pressure is the most significant factors affecting vascular endothelial function, followed by pulse pressure and diastolic blood pressure.