速度向量成像技术早期无创性评价动脉硬化的临床研究

目的探讨冠心病组和正常对照组颈动脉运动速度、应变及应变率的变化。方法对86例冠心病患者颈动脉无斑块部位和50例健康体检者进行双侧颈动脉高频超声检查，测量颈动脉内膜．中层厚度（IMT），应用速度向量成像（VVI）技术跟踪颈动脉的运动速度、应变、应变率，测量各项指标及肱动脉内皮依赖性舒张功能。结果冠心病组颈动脉内膜一中层厚度、弹性系数和僵硬度均高于正常对照组（P〈0．05），冠心病组内皮依赖性舒张反应肱动脉内径变化数值低于正常对照组（P〈0．05）；冠心病组颈动脉无斑块部位长轴的收缩期径向最大运动速度、最大应变率分别低于正常对照组（P〈0．05）；冠心病组颈动脉无斑块部位短轴的径向运动速度、旋转率、周向应变及应变率均低于正常对照组（P〈0．05）。冠心病组颈动脉径向运动速度与弹性系数呈负相关（r=-0．464，P=0．002）。讨论VVI技术可检测血管壁的弹性变化，颈动脉运动的机械不一致性和不同部位的力学指标差别，有可能作为动脉硬化早期检测和定量评价指标。

Clinical study on early diagnosis of carotid sclerosis by using ultrasonic velocity vector imaging

Objective To assess the vascular changes of the velocity, strain and strain rate in groups of control and coronary heart disease （CHD） without plaque. Methods A total of eighty-six patients with CHD according to the results of coronary arteriography （CAG） and 50 healthy subjects took the high fre- quency ultrasound scanning in two carotid arteries. The carotid artery intima-media thickness was detected. The velocity vector imaging speckle tracking was utilized to track the velocity, strain and stain rate of carot- id. The mechanical parameters of carotid intima were measured simultaneously and calculated automatically. Results The ultrasound-derived IMT, elasticity coefficient and stiffness in the patients with CHD were high- er than those in the group of healthy subjects （ all P 〈 0.05）. The systolic maximum velocity and strain rate of carotid long axis with CHD were significantly lower than those in the control group （ all P 〈 0.05 ）. The systolic radial velocity, rotation rate, circumferential strain and strain rate of carotid short axis with CHD were significantly lower than those with normal control （ P 〈 0.05 ）. There was negative correlation of systolic radial velocity in short axis and elasticity coefficienee （ r = - 0. 464, P = 0. 002 ）. Conclusions The VVI technique could detect the elasticity of blood vessel wall, sclerosis and the mechanism asynehrony of the carotid artery.