速度向量成像技术评价二叶式主动脉瓣患者升主动脉弹性的价值

The Clinical Value of Velocity Vector Imaging In Evaluating the Elasticity of the Ascending Aorta in Patients with Bicuspid Aortic Valve

目的探讨速度向量成像(velocity vector imaging,VVI)技术评估二叶式主动脉瓣(bicuspid aortic valve,BAV)患者升主动脉弹性的临床应用价值。方法选取BAV患者40例作为病例组,选择与病例组年龄、性别相匹配的健康体检者20例作为对照组。首先用M型超声测量升主动脉舒张末期内径和收缩末期内径,同时测量并记录血压值,通过公式计算出升主动脉弹性参数:升主动脉应变(AS)、升主动脉僵硬指数(ASI)和升主动脉扩张性(ADIS)。再应用VVI技术测量升主动脉前、后壁的最大纵向运动速度(Vs)、位移(Ds)、应变值(S_(max))及应变率(SR_(max))参数,比较各组间参数。结果病例组升主动脉内径较对照组增宽,升主动脉应变和扩张性均较对照组减低,升主动脉僵硬指数较对照组增加(P均<0.01)。病例组升主动脉前、后壁的最大纵向应变值、应变率均较对照组减低(P均<0.05)。病例组升主动脉前壁应变值与升主动脉应变呈正相关(r=0.371,P=0.004),与僵硬指数呈负相关(r=-0.383,P=0.003),与扩张性呈正相关(r=0.278,P=0.032)。升主动脉后壁应变值与升主动脉应变呈正相关(r=0.272,P=0.036),与升主动脉僵硬指数、升主动脉扩张性未见相关(P均>0.05)。结论BAV患者升主动脉弹性减低。VVI技术可以作为评价BAV患者升主动脉弹性的一种新技术,且测得的升主动脉应变参数与M型超声检测并计算的升主动脉弹性参数相关性良好。

Objective To explore the clinical application value of velocity vector imaging in evaluating the elasticity of the ascending aorta in patients with bicuspid aortic valve.Methods In strict accordance with the inclusion and exclusion criteria,40 patients with bicuspid aortic valve were selected as the case group,and 20 healthy subjects who matched the age and sex of the case group were included in the control group.First,the diameter of proximal ascending aorta at the end of diastolic and systolic phases were measured by M-mode ultrasound,and the blood pressure was measured and recorded at the same time.Then the ascending aortic elasticity parameters including aortic strain,aortic stiffness index,and aortic distensibility were calculated using the formula.The velocity vector imaging technology was used to measure the maximum longitudinal velocity,displacement,strain and strain rate of the anterior and posterior wall during the systolic and diastolic periods,and the parameters were compared between groups.Results The diameter of the ascending aorta in the case group was wider than that in the control group,and the strain and distensibility of the ascending aorta were lower than those in the control group,and the ascending aortic stiffness index increased in the case group(P all<0.01).The maximum longitudinal strain and strain rate of the ascending aorta in the case group were lower than those in the control group(P all<0.05).In the case group,the ascending aortic anterior wall strain was positively correlated with the aortic strain(r=0.371,P=0.004),negatively correlated with the stiffness index(r=-0.383,P=0.003),and positively correlated with distensibility(r=0.278,P=0.032).The ascending aortic posterior wall strain was positively correlated with the ascending aortic strain(r=0.272,P=0.036),and was not significantly related to the ascending aortic stiffness index and ascending aortic distensibility(P>0.05).Conclusion The ascending Aortic elasticity in patients with bicuspid aortic valve are decreased.VVI technology can be used as a new technology to evaluate the ascending aortic elasticity in patients with bicuspid aortic valve,and the strain of the anterior and posterior walls in patients with bicuspid aortic valve had a good correlation with the elastic parameters of the ascending aorta detected and calculated by M-mode ultrasound.