Clinical Study of the Ascending Aorta Wall Motion by Velocity Vector Imaging in Patients with Primary Hypertension

We studied the wall motion characteristics of the ascending aorta by velocity vector imaging （VVI） in primary hypertension patients. The ascending aortas both in 30 patients with primary hypertension and 30 normal controls were examined by Acuson sequoia 512 equiped with VVI. The maximum velocity （Vs, Ve） of every point on the anterior wall of ascending aorta both in systole and diastole was measured. The aortic diameter was wider in the hypertension patients than that in the healthy subjects （P〈0.05）. The movement amplitude of the anterior wall of the ascending aorta in long axis view in the hypertension patients was lower than that in the healthy subjects （P〈0.05）. The motion and time to peak in systole of each point of the ascending aorta in the healthy subjects had no significant difference （P〉0.05）. The velocity curves of the anterior wall of ascending aorta both in the hypertension and healthy subjects were regular, and the curve in systole was named S wave and that in diastole named E wave. The velocity of S wave and E wave was slower in the hypertension patients than that in the healthy subjects （P〈0.05）. The time to peak of S wave on the anterior wall of ascending aorta in systole was shorter in the hypertension patients than in the healthy subjects （P〈0.05）. VVI could be used to accurately and directly observe the movement character of the ascending aorta walls, which would help us understand the elasticity of great arteries in patients with hypertension.

Comparison of Elastic Properties of Bilateral Carotid Arteries in Relation to Site of Acute Ischemic Stroke Using Velocity Vector Imaging

INTRODUCTIONlschemic stroke accounts for 70% of all the cerebrovascular diseases. Severe stenosis and occlusions ofextracranial and intracranial artery are all important risk factors causing ischemic stroke. Based on the widespread observation worldwide, intracranial atherosclerosis is the most common vascular lesions in Asians, Hispanics, and Africans. Therefore, accurate and noninvasive methods fbr early diagnosis of stroke in individuals without significant stenosis of the extracranial carotid artery is of considerable clinical interest.

Evaluation of the asynchronization and function of the left ventricle in patients with chronic pulmonary hypertension by velocity vector imaging

Background Pulmonary hypertension （PH） is a set of pathophysiological syndromes characterized by increased pulmonary artery pressure and pulmonary vascular resistance,resulting in increased right ventricular afterload.The left and right ventricles interact through hemodynamics.What impact will PH have on synchronization and function of the left ventricle （LV）？ The aim of this study was to evaluate the synchronization of the left ventricular wall motion and left ventricular function in patients with varying degrees of PH using velocity vector imaging （Wl） technology.Methods Sixty patients with chronic PH served as the experimental group,and 20 healthy volunteers served as the control group.According to the different degrees of pulmonary artery systolic pressure,the experimental group was divided into three groups：mild,moderate,and severe PH groups.The time to peak systolic longitudinal velocity （Tvl）,the peak systolic longitudinal velocity （Vsl）,the peak diastolic longitudinal velocity （Vel）,the peak systolic longitudinal strain （SI）,and strain rate （SRI） in 18 segments were measured in each group.Results TvI in the control group and each group with PH was reduced from basal to apical segment,and in control group Tvl in various segments of the same wall and in different walls showed no significant difference （P ＞0.05）.With increase in pulmonary artery pressure,Tvl values measured showed an increasing trend in groups with PH.In groups with PH,Vsl and Vel of each wall were reduced sequentially from basal to apical segments,showing gradient change; Vsl and Vel values measured showed a decreasing trend with increase in pulmonary artery pressure,in which the differences of Vel values measured in the control group and the mild PH group were statistically significant （P ＜0.01）,and the differences between other groups were statistically significant （P ＜0.01）.In groups with PH,SI and SRI in basal segment and the middle segment of each wall were decreased; the difference between groups was statistically significant （P ＜0.01）.Conclusions Asynchronization of the LV and decreased left ventricular function were present in patients with chronic PH;WI technology can accurately evaluate left ventricular function in patients with PH,and indicators such as Tvl,Vsl,and Vel are valuable.

Use of velocity vector imaging technology to evaluate the motion of myocardial infarction

Background The velocity vector imaging is an ultrasound speckle imaging that was recently developed, which is based on the two-dimensional gray scale image, with more accurate tracking process and more conve-nient and time-saving operation method can quantitatively displays the varied curve of myocardial velocity and direction sampling taking from multiple parts in one cardiac cycle by tracking the space motion of echo spots of the cardiovascular tissue, and then analyze their movements, avoiding the angular dependence and the limita-tions of analysis section that could effect on Doppler technology. The technology provides a new auxiliary method for the diagnosis and treatment of cardiovascular disease and is valuable on clinical diagnosis and scientific re-search and a wide horizon of development.

Deformation of the left and right ventricular longitudinal myocardium in fetuses with umbilical cord around neck

Background Umbilical cord around neck, a common obstetric complication, affects fetal hemodynamics. Does it influence fetal cardiac functions？ The purpose of this study was to investigate the left and right ventricular systolic and diastolic functions of fetuses with umbilical cord around neck in the third trimester by applying velocity vector imaging （VVI）. Methods Thirty-five cases of fetuses with umbilical cord around neck whose gestational ages from 35 to 40 weeks were selected, including 20 cases of umbilical artery ratio of the highest systolic velocity （S） to the lowest diastolic velocity （D） （S/D） 〈3.0 and 15 cases of umbilical artery S/D ≥3.0, while 20 cases of normal fetuses of 35–40 gestational weeks were selected as the control group. The changes in longitudinal velocity, strain, and strain rate of fetal left and right ventricle in systole and diastole in two groups, and the changes in fetal cardiac function under the situation of umbilical cord around neck were analyzed.Results Longitudinal strain and strain rate overall of fetal left and right ventricle in systole and diastole were less in fetuses with umbilical artery S/D 33.0 and umbilical cord around neck than those in fetuses with umbilical artery S/D 〈3.0 and those in control group （P 〈0.05）; there was no significant difference （P 〉0.05） in longitudinal strain and strain rate overall of fetal left and right ventricle in systole and diastole between fetuses with umbilical artery S/D 〈3.0 and those in control group.Conclusions Left and right ventricular systolic and diastolic dysfunction was detected in fetuses with umbilical cord around neck and umbilical artery S/D 33.0. VVI could sensitively respond to cardiac function changes in fetuses with umbilical cord around neck, which provides another valuable method in the evaluation of fetal cardiac function.