Velocity Vector Imaging Parameters Research Articles

Additional effects of combination therapy of antihypertensive medication on aortic elastic properties beyond blood pressure lowering effect in spontaneously hypertensive rats

Abstract Background Combination therapy in the treatment of hypertension provides better therapeutic efficacy, improved tolerability by lowering the dose and reduced potential for side effects than monotherapy. Especially, combinations of calcium channel blocker (CCB), angiotensin receptor blocker (ARB) or diuretics (thiazide) are generally effective and well tolerated regimen in antihypertensive treatment. However, we have focused more on the antihypertensive power of the combination therapy rather than the effect on the vessel itself. Purpose The purpose of this study is to determine the efficacy of antihypertensive medications as ARB and CCB and its combination with or without thiazide on the aortic structural and functional properties beyond the effect of blood pressure (BP) lowering. Methods Fourteen-week-old male spontaneous hypertensive rats were randomly divided into 5 groups, and treated with 1) vehicle (V), 2) amlodipine besylate (A), 3) olmesartan (O), 4) combined amlodipine and olmesartan (AO) or 5) combined amlodipine, olmesartan and thiazide (AOD), respectively. After 8 weeks of treatment, hemodynamic parameters and structural and functional properties of aorta as intima-media thickness (IMT) and velocity vector imaging (VVI) parameters of aorta including fractional area change (FAC), circumferential strain (CS) and strain rate (CSR) were assessed in each group and collagen contents of aorta were quantified as well. Results During the study period, systolic and diastolic BP were serially decreased in all treatment groups. Especially, AOD group showed lowest systolic and diastolic BP levels and also showed smallest IMT and vessel area and highest elasticity (FAC and CS) among the other groups (p<0.01) at 8 weeks (Table 1). In histologic analysis, collagen contents of aorta in all treatment groups showed significant associations with BP, IMT and VVI parameters (FAC, CS, CSR) (p<0.05), respectively. Particularly, aorta of AO and AOD groups showed significantly lower levels of collagen contents than that of control group. (p< 0.05) (Figure 1) Conclusion(s) Beyond the BP lowering effect, combination of amlodipine and olmesartan with or without thiazide minimize structural changes and shows better protection for the progression of arteriosclerosis than individual monotherapy in treatment of hypertension.Table 1Figure 1

Vascular Alterations Preceding Arterial Wall Thickening in Overweight and Obese Children.

Background: Childhood obesity is linked to adverse cardiovascular outcomes in adulthood. This study aimed to assess the impact of childhood obesity on the vasculature and to investigate whether vascular alteration precedes arterial wall thickening in childhood. Methods: A total of 295 overweight (body mass index [BMI] 85th to 95th percentile, n = 30) and obese (BMI ≥ 95th percentile, n = 234) children aged 7–17 years and 31 normal-weight controls with similar age and gender were prospectively recruited. We assessed anthropometric data and laboratory findings, and measured the carotid intima–media thickness (IMT), carotid artery (CA) diameter, M-mode-derived arterial stiffness indices, and velocity vector imaging parameters, including the CA area, fractional area change, circumferential strain, and circumferential strain rate (SR). Results: The mean ± standard deviation age of the participants was 10.8 ± 2.1 years; 172 (58%) children were male. Regarding structural properties, there was no difference in the IMT between the three groups. The CA diameter was significantly increased in obese children, whereas the CA area showed a significant increase beginning in the overweight stage. Regarding functional properties, contrary to β stiffness and Young’s elastic modulus, which were not different between the three groups, the circumferential SR showed a significant decrease beginning in the overweight stage and was independently associated with BMI z-scores after adjusting for covariates. Conclusion: We have demonstrated that arterial stiffening and arterial enlargement precede arterial wall thickening, and that these vascular alterations begin at the overweight stage in middle childhood or early adolescence.

Velocity Vector Imaging to Assess Longitudinal Wall Motion of Adult Carotid Arteries.

We aimed to assess longitudinal wall motion of the common carotid artery (CCA) using velocity vector imaging (VVI). From October 2018 to July 2019, we prospectively performed VVI of 204 CCAs (102 adult volunteers, 57 men, 45 women) in young (n = 40, 20-44 y), mid-age (n = 30, 45-64 y), and senior (n = 32, ≥65 y) groups. VVI parameters of CCA included longitudinal motion pattern, motion parameters (strain, strain rate, displacement), and time-to-peak motion parameters (time-to-peak strain, time-to-peak strain rate, time-to-peak displacement). Statistical analyses included one-way ANOVA post-hoc testing to examine the difference in VVI parameters among the 3 age groups and in paired groups; unpaired t tests to examine the difference in VVI parameters between CCAs with and without atherosclerotic plaque, between hypertensive and normotensive subjects without atherosclerotic plaque; linear regression to analyze correlations of VVI parameters to age, carotid intima-media thickness; and intraclass correlation coefficient to test inter- and intra-observer reliability in performing VVI of the CCA. Differences in VVI parameters and patterns among the 3 age groups, between hypertensive and normotensive, and CCAs with and without plaque were significant (p < .01). CCA motion- and time-to-peak motion parameters were correlated to age (R2 = 0.63-0.56) and carotid intima-media thickness (R2 = 0.29-0.22). CCA wall motion dyssynchrony was remarkable in seniors. The repeatability and reproducibility for performing carotid artery VVI were good (intraclass correlation coefficient > 0.85). VVI is feasible to assess changes in longitudinal CCA wall mechanical properties and synchrony with aging, atherosclerosis, and hypertension.

Quantitative Assessment of Cardiac Function in Fetuses of Women with Maternal Gestational Thyroid Dysfunction Using VVI Echocardiography.

BackgroundThe study aimed to investigate the clinical value of velocity vector imaging (VVI) in assessing heart function in fetuses of pregnant women with thyroid dysfunction. The inter-observer and intra-observer variability was assessed for all VVI parameters observed.Material/MethodsThe participants were enrolled from singleton pregnant women with gestational ages ranging 24+0 to 40+1 weeks who visited the Department of Obstetrics and Gynecology at the Affiliated Hospital of Qingdao University, China, for prenatal care from July 2011 to February 2014. Digital 2-dimensional (2D) dynamic 4-chamber images of the heart were collected. A total of qualified 226 images from 125 fetuses of pregnant women with normal thyroid (control group), 64 fetuses of pregnant women with hypothyroidism (hypothyroidism group), and 37 fetuses of pregnant women with hyperthyroidism (hyperthyroidism group) were interrogated offline using VVI software. The echocardiographic parameters including the myocardium peak systolic velocity (Vs), peak diastolic velocity (Vd), peak systolic strain (S), peak systolic strain rate (SRs), peak diastolic strain rate (SRd) of RV and LV, were obtained from the velocity curves of 2D myocardial motion. The heart rate was measured using a virtual M-mode algorithm built into the software.ResultsThe study found that the longitudinal Vs and Vd of both ventricles in the control group gradually decreased from basal segments to apical segments and significantly increased over the gestation. S, SRs, and SRd of both ventricles remained stable after middle gestation. Compared with the control group, the hypothyroidism and hyperthyroidism groups exhibited significantly reduced S, SRs, and SRd, even for fetuses at 24-weeks gestation. There were no significant differences in global Vs and global Vd between the control group and the hyperthyroidism or hypothyroidism groups.ConclusionsThe thyroid dysfunction of pregnant women may damage fetal heart function, and VVI could be a sensitive technique to measure the variation of fetal heart function.

Application of velocity vector imaging and dobutamine stress echocardiography in evaluating the strain of left ventricular in the long axis views in diabetic patients with LVEF ＞50％

Objective To assess the systolic strain of left ventricular(LV) in the long axis views in diabeties mellitus(DM) patients with LVEF value ＞ 50％ with velocity vector imaging (VVI) and dobutamine stress echocardiography (DSE).Methods Thirty DM patients,which were excluded from coronary artery disease,valvular heart diseases,congenital heart diseases,hypertension,and LVEF value ＞50％ by echocardiography,and 20 volunteers with age and sex matched were involved in the study.Two-dimensional VVI echocardiographic cine loops were stored at baseline and dobutamine stress in the apical four-chamber,two-chamber and long axis views of LV.The maximum long systolic velocity (Vs),strain (e)and strain rate (SR) were obtained from sygno VVI software.Results The Vs,e and SR decreased from basal to apical in the LV walls whether in the control group or in the DM group.At baseline,SR in 7 segments,e in 4 segments and Vs in 3 segments in the DM group decreased significantly than those in the control group (P ＜0.05).After the maximum dobutamine stress,all parameters decreased significantly in the DM group than those in the control group (all P ＜0.05).In addition,67％ parameters in apical LV and 11％ parameters in middle LV in the DM group were lower than those in the control group.All parameters in basal LV were comparable between the two groups at baseline.Conclusions The Vs,e and SR showed decreased tendency from basal to apical in the long axis of LV.The Vs,e and SR impairment in the long axis of DM patients appeared first in apical tissue of LV.DSE could increase the sensitivity of VVI parameters in the earlier stage. Key words: Echocardiography, stress; Diabetes mellitus; Ventricular function, left; Dobutamine; Velocity vector imaging

Evaluation of systolic function of left ventricular in the short axis views in diabetic patients with ejection fraction>50％with velocity vector imaging and dobutamine stress echocardiography

Objective To evaluate the systolic function of left ventricle(LV) in the short axis views in diabetic patients with ejection fraction (EF) value ＞ 50％ with velocity vector imaging (VVI) and dobutamine stress echocardiography (DSE).Methods 30 diabetic patients,which were excluded from coronary artery disease,hypertension,valvular heart diseases,congenital heart diseases,and EF value ＞50 ％by echocardiography,and 20 volunteers with age and sex matched were involved in the study.Twodimensional VVI echocardiographic cine loops were stored at baseline and dobutamine stress (10,20,30 and 40 μg · kg-1 · min-1) in the basal,middle and apical short axis views of LV.The maximum systolic velocity (Vs),strain (e) and strain rate (SR) were obtained from sygno VVI software.Results The Vs,e and SR showed decrement tendency from basal to apical short axis view whether in the control group or in the DM group.At baseline,the SR in the apical view decreased significantly in the DM group than that in the control group (P ＜0.05),other parameters were comparable between the two groups.After 10 μg· kg-1 · min-1 dobutamine stress,the SR in the middle and apical views and Vs,e in the apical view decreased significantly in the DM group than those in the control group (all P ＜ 0.05).After 20μg· kg-1 · min-1 dobutamine stress,the SR in the basal,middle and apical views and Vs,e in the middle and apical views decreased significantly in the DM group than those in the control group (all P ＜0.05).After the maximum dobutamine stress,all parameters decreased significantly in the DM group than those in the control group (all P ＜0.05).Conclusions The systolic function impairment of DM patients appeared first in the apical tissue of LV,SR was more sensitive index than velocity arnd strain,DSE could increase the sensitivity of VVI parameters in detecting the myocardial systolic function impairment in the earlier stage. Key words: Echocardiography, stress; Diabetes mellitus; Ventricular function, left; Dobutamine; Velocity vector imaging

Quantitative Assessment of Aortic Elasticity With Aging Using Velocity-Vector Imaging and Its Histologic Correlation

Velocity-vector imaging (VVI) represents a valuable new method for noninvasive quantification of vascular properties associated with aging. The purpose of this study was to assess the correlations between VVI parameters and histological changes with aging. Fourteen mongrel dogs were classified as either young (n=7; age, 1-2 years; female; weighing 22-29 kg) or senescent (n=7; age, 8-12 years; female; weighing 36-45 kg). The short-axis image of the descending thoracic aorta was obtained for VVI analysis with transesophageal echocardiography. The location of the image was identified using fluoroscopic guidance, and the aortic tissue was extracted. After dividing the aortic wall into 6 segments, both regional and segmental tissue collagen and elastin contents were quantified and correlated with the aortic elastic properties. In the regional analysis, the M-mode-derived aortic dimensions and elastic moduli except for intima-media thickness were not significantly different between the groups, whereas the VVI-derived aortic area and fractional area changes showed more dilated and stiffer aorta in senescent dogs. Also, fractional area change was significantly correlated with the tissue collagen content unlike the M-mode-derived elastic moduli. In the segmental analysis, the radial velocity, circumferential strain, and strain rates of VVI were more reduced in senescent dogs than young dogs, and the radial velocity and circumferential strain showed independent associations with the collagen content of the corresponding aortic wall. VVI was a feasible method for direct quantification of aortic elastic properties with a significant histological correlation.

Predicting Myocardial Recovery in Children with Dilated Cardiomyopathy

Purpose Dilated cardiomyopathy (DCM) is a common indication for heart transplantation (Tx) in children but not all progress to Tx. Standard 2D echocardiography (2DE) and Doppler techniques do not predict which patients will recover function. Myocardial function can be reliably determined using Velocity Vector Imaging (VVI), an angle independent method of evaluating myocardial mechanics using conventional 2DE images. We believe VVI provides a valid and reproducible measure of myocardial function in DCM patients with correlation to clinical outcomes. Methods and Materials Medical records and 2DEs were retrospectively reviewed on patients with DCM. VVI analysis was performed offline using Siemens Syngo software. Using VVI on a 4 chamber image, longitudinal velocity (LVel), strain (S), strain rate (SR) were obtained. Ventricular functional parameters were compared to normal. Results 22 patients were treated for DCM − 8 patients recovered function, 4 patients underwent Tx, 3 patients were listed for Tx, 7 patients died without recovering or while awaiting Tx. Mortality was associated with mechanical, ventilatory support, and renal failure. The overall mortality rate was 36% (8/28). LVel, S, and SR were decreased compared to normal in all groups. LVel, S, and SR were statistically different in those who progressed to Tx and listed for Tx compared to those who did recover. S and SR did not return to normal even in the group who clinically recovered. Ejection fraction and 2DE dimensions correlated with VVI parameters. Conclusions VVI derived myocardial functional parameters do not return to normal despite clinical recovery and return to normal of conventional 2DE parameters. VVI is an effective tool to predict degree of myocardial recovery and serves as an adjunct to conventional 2DE measures of systolic and diastolic function.

VALUE OF VELOCITY VECTOR IMAGING IN THE DETECTION OF THE LEFT VENTRICULAR SYSTOLIC DYSFUNCTION IN EARLY DIABETIC RATS

ObjectivesThe aim of this study was to investigate the left ventricular systolic dysfunction in early diabetic rats with velocity vector imaging (VVI).MethodsThe diabetes mellitus (DM) group comprised 12 male diabetic...

Correlation between Myocardial Dysfunction and Perfusion Impairment in Diabetic Rats with Velocity Vector Imaging and Myocardial Contrast Echocardiography

The purpose of this study was to investigate whether myocardial systolic dysfunction and perfusion impairment occur in diabetic rats, and to assess their relationship using velocity vector imaging (VVI) and myocardial contrast echocardiography (MCE). Forty-six rats were randomly divided into either control or the diabetes mellitus (DM) groups. DM was induced by intraperitoneal administration of streptozotocin. Twelve weeks later, 39 survival rats underwent VVI and MCE in short-axis view at the middle level of the left ventricle, both at rest and after dipyridamole stress. VVI-derived contractile parameters included peak systolic velocity (Vs ), circumferential strain (εc ), strain rate (SRc ), and their reserves. MCE-derived perfusion parameters consisted of myocardial blood flow (MBF) and myocardial flow reserve (MFR). At rest, SRc in the DM group was significantly lower than in the control group, Vs , εc , and MBF did not differ significantly between groups. After dipyridamole stress, all VVI parameters and their reserves in the DM group were significantly lower than those in the control group, MBF and MFR were substantially lower than those in the control group, too. Meanwhile, significant correlations between VVI parameter reserves and MFR were observed in the DM group. Both myocardial systolic function and perfusion were impaired in DM rats. Decreased MFR could be an important contributor to the reduction in myocardial contractile reserve.

Two-Dimensional Strain Rate and Doppler Tissue Myocardial Velocities: Analysis by Echocardiography of Hemodynamic and Functional Changes of the Failed Left Ventricle during Different Degrees of Extracorporeal Life Support

To evaluate hemodynamic and functional changes of the failed left ventricle by Velocity Vector Imaging (VVI) and tissue Doppler, 22 patients with cardiogenic shock supported by extracorporeal life support (ECLS) were imaged during ECLS output variations inducing severe load manipulations. The following data were acquired: (1) mean arterial pressure, aortic Doppler velocity-time integral, left ventricular end-diastolic volume, and mitral Doppler E wave; (2) tissue Doppler systolic (Sa) and early diastolic (Ea) velocities; and (3) systolic peak velocity (Sv), strain, and strain rate using VVI. Load variations were documented by a significant decrease in afterload (mean arterial pressure, -21%), an increase in preload (left ventricular end-diastolic volume, +12%; E, +46%; E/Ea ratio, +22%), and an increase in the velocity-time integral (+45%). VVI parameters increased (Sv, +36%; strain, +81%; and strain rate, +67%; P < .05), unlike tissue Doppler systolic velocities (+2%; P = NS). Whatever the ECLS flow, Sa was higher in patients who survived. VVI parameters are not useful in characterizing the failed left ventricle with rapidly varying load conditions. Tissue Doppler systolic velocities appear to be load independent and thus could help in the management of ECLS patients.

Value of velocity vector imaging and stress echocardiography in the assessment of systolic function of left ventricular in diabetic rats

Objective To investigate whether velocity vector imaging (VVI) combined with stress echocardiography could detect potential myocardial impairment of the left ventricle(LV) in diabetic rats.Methods DM rats ( n = 18,administered by STZ at 65 mg/kg) and control rats( n = 12) were performed with VVI and M-mode echocardiography both at rest and after dipyridamole stress 12 weeks later. Twodimensional echocardiographic cine loops and M-mode images of three consecutive beats were obtained from the short-axis views at the mid-LV level. The means of segmental peak systolic velocity(Vs), circumferential strain(ec) ,radial strain(er), systolic circumferential and radial strain rate (SRc, SRr) and the percent wall thickening (WT% ,derived from M-mode) were obtained. After echocardiograms were performed,the hearts were excised and prepared for HE staining and ultrastructural observations under electron microscopy.Results At rest,only SRc in the DM group was significantly lower than that in the control group( P ＜0.05), the other parameters were statistically comparable between the two groups. After dipyridamole stress,all VVI values in the DM group were significantly lower than those in the control group ( P ＜0.05).However,there was no significant difference in WT% between the two groups either at rest or after dipyridamole stress ( P ＞0.05). Conclusions The VVI parameters combined with dipyridamole stress are more effective in evaluating potential myocardial impairment of the LV walls in diabetic rats. SRc might be more sensitive indices that can be used to detect myocardial impairment at rest. Key words: Echocardiography,stress; Diabetes mellitus; Ventricular function,left; Dipyridamole; Velocity vector imaging

Assessment of regional right ventricular longitudinal functions in fetus using velocity vector imaging technology

The velocity vector imaging (VVI) technique is useful to assess regional myocardial mechanics. The aim of this study was to evaluate the usefulness of this technology in assessing regional right ventricular longitudinal functions in the fetus and to establish a nomogram of the right ventricle (RV). We studied 170 healthy fetuses that were divided into five groups based on gestational age. Dynamic digital images of four chambers were collected and analyzed off-line. The longitudinal VVI parameters were calculated in the right free wall and ventricular septum, respectively. A total of 151 out of 170 fetuses (89%) were successfully analyzed using VVI, with good inter- and intra-observer agreements. Normal values for velocity, strain, and strain rate were established. The tissue velocity gradually decreased from basal to apical segment (P < 0.05), whereas strain and strain rate remained stable. The tissue velocity increased with gestational age (P < 0.05), whereas strain and strain rate were stable (P > 0.05). Fetal myocardial velocity, strain, and strain rate measurements are easy to obtain and are reproducible. From mid-to-late gestation, the longitudinal tissue velocity of the RV increases with gestational age, whereas strain and strain rate remain stable. These results indicate that myocardial contractility is established in mid-gestation and remains constant throughout gestation.

Assessment of Left Ventricular Wall Motion in Diabetic Rats Using Velocity Vector Imaging Combined with Stress Echocardiography

The aim of this study was to investigate whether velocity vector imaging (VVI) combined with stress echocardiography could detect potential diffused myocardial impairment of the left ventricle (LV) in diabetic rats. Thirty-five male SD rats were randomly divided into either the control group or the diabetes mellitus (DM) group (induced with STZ). VVI was performed both at rest and after dipyridamole stress in all rats 12 weeks later. Segmental peak systolic velocity (V(s)), diastolic velocity (V(d)), radial strain (epsilon(r)), circumferential strain (epsilon(c)), systolic and diastolic radial strain rate (SR(r)), and circumferential strain rate (SR(c)) were measured from six segments at the mid-level of the LV. At rest, systolic and diastolic SR(c) in the DM group were significantly lower than those in the control group. After dipyridamole stress, all VVI parameters in the DM group were significantly lower than those in the control group, although all values increased significantly after dipyridamole stress compared to those at rest in both groups. The VVI-derived V(s,) V(d), epsilon(r), epsilon(c), systolic and diastolic SR(r) and SR(c), combined with dipyridamole stress are all effective parameters in evaluating potential myocardial impairment due to ultrastructural alterations of cardiocytes and microcirculation disturbances in DM rats. Systolic and diastolic SR(c) may be more sensitive indices that could be useful in detecting myocardial impairment at rest.