速度向量技术测定糖尿病患者肱动脉血管的生物力学性质

目的采用速度向量技术（velocity vector imaging，VVI）评价2型糖尿病患者肱动脉的生物力学特征。方法2型糖尿病患者和健康对照组各20例，于基础状态和舌下含服硝酸甘油（nitroglycerin，NTG）后，分别应用二维超声与VVI技术测定肱动脉舒张末期内径、面积与血管应变。通过Langewouters公式计算肱动脉血管力学参数，并描绘糖尿病组和对照组在两种状态下肱动脉的压力一血管面积曲线与应变一应力曲线。结果糖尿病组NTG状态下肱动脉血管内径增量、血管面积增量、血管壁应力的降幅均较对照组明显减小（P〈0．05），应变一应力曲线出现右移现象。结论VVI可评判在体肱动脉的生物力学特征，并为无创性判定糖尿病患者外周血管病变生物力学分析提供了新思路。

Biomechanical properties of brachial artery measured by velocity vector imaging in patients with type 2 diabetes

Objective To evaluate the application of two-dimensional ultrasonography and vetoclty vector imaging （VVI） in measurement of biomechanical properties of brachial artery （BA） in patients with type 2 diabetes mellitus （T2DM）. Methods Twenty patients with T2DM were enrolled in the study and 20 healthy subjects served as controls. Ultrasound images of BA were displayed and diameter, area and strian of BA were documented from the sonogram and VVI. Biomechanical data in BA were calculated according to Langewouters＇ equation. Curves of pressure-area and stress-strain were mapped and compared at baseline and during nitroglycerin intervention in the patients and the controls. Results Increments of diameter, area, compliance and the decrements of stress of BA were attenuated after intervention of nitroglycerine significantly （P 〈 0. 05 ）. Strain-stress curve was markedly shifted rightward in T2DM patients compared to that of controls. Conclusion VVI can effectively assess the biomechanical properties of BA, which provides a non-invasive measure for analysis of peripheral artery in patients with T2DM.