The Evaluation Of The Carotid Artery Wall Elasticity In Patients With Hypertension By Using VVI Technology

ObjectiveTo evaluate the carotid artery elasticity in patients with hypertension by measuring the carotid artery wall motion with velocity vector imaging technologyMethods:80patients with hypertension (HP) and40patients in normal control group (NC) were investigated. The patients in HP group were divided into two subsets according to the carotid artery intima-media thickness (IMT) measured by high frequency ultrasound detection:patients with primary hypertension not associated with carotid atherosclerosis (HNCA)group (40patients), Systolic blood pressure≥140mmHg and/or Diastolic blood pressure>90mmHg and IMT<1.0mm; and patients with primary hypertension associated with carotid atherosclerosis (HCA) group (40patients), Systolic blood pressures≥140mmHg and/or Diastolic blood pressure≥90mmHg and IMT≥1.0mm.The measurements were performed with Siemens Sequoia-512color Doppler ultrasonic diagnostic apparatus, equipped with VVI image analysis software and workstation, which works with15L8linear array probe in frequency of8.0to14.0MHz. The equipments works in conventional two-dimensional ultrasound and M type mode to measure the IMT, End-systolic diameter (Ds), end-diastolic diameter (Dd) and to calculate the difference (^D),the stiffness (β) and compliance (C). Under ⅤⅥ model, evaluate the carotid artery vascular intimal sites short axis strain and strain rate, measure the maximum strain of systolic (Ssm) and the maximum strain rate of systolic (SRsm) and compared. The application of the SPSS16.0statistics software package was used for statistical processing of data.Results1. Gernerally, there’re no significant differences in age, gender, left ventricular systolic function, heart rate, fasting blood glucose and blood lipid indexes for the patients in the three groups (P>0.05); the systolic blood pressure and pulse pressure (A P) of the patients in the3groups is different (p<0.05), the hihg-low order is NC group<HNCA group<HCA group; the diastolic blood pressure of the patients in HP group is higher than the NC group (P<0.05); there’s no significant difference between the two subgroups in HP group (P>0.05).2. Comparison of conventional two-dimensional ultrasound measurements and elastic derived parameter:the IMT of the patients in HCA group increased compare with the NC group and HNCA group (P<0.01). There’s no significant difference in IMT of patients in HNCA group and NC group (P>0.05). the Ds and Dd of the patients in HCA group increased compare with the NC group and HNCA group (P<0.05); the D of the patients in HCA group is higher than NC group and HNCA group (p<0.05), and there’s no significant difference between NC group and HNCA group (p>0.05). The high-low order for β is HCA group> HNCA group> NC group (p<0.05); and the order for Compliance is HCA group<HNCA group<NC group (p<0.05), and the β and Compliance of the patients in the HCA group is significant different from the NC group and the HNCA group(P<0.01).3. There’s no significant difference in the Ssm and SRsm of the patients in each group (p>0.05). And there’s significant difference in the Ssm and SRsm of the patients among the3groups(p<0.05); the high-low order is as the following:HCA group<HNCA group<NC group; and the Ssm and SRsm of the patients in the HCA group is significant different from the NC group(P<0.01).Conclusions1. VVI technology can be used for quantitative evaluation of carotid artery wall elasticity, and can reflect the variation in carotid artery elasticity in absence of increased thickness in IMT.2. Ssm and SRsm decreased gradually in NC group, HNCA group and HCA group, which present that the sclerosis degree of vessel wall gradually increased. The more obviously the Ssm and SRsm decreased, the poorer the pipe wall deformation ability is. Ssm and SRsm are more sensitive than IMT and D parameters to the carotid artery elasticity.3. In combination of the parameters measured by VVI technology and the conventional ultrasonic detection index, the morphological structure and elastic state of carotid artery wall can be more comprehensive understood and evaluated.