Ejection Period Research Articles

Prolonged vortex formation during the ejection period in the left ventricle with low ejection fraction: a study by vector flow mapping.

Vortex formation in the left ventricle (LV) can be visualized by novel vector flow mapping (VFM) based on color Doppler and speckle tracking data. The aim of this study was to evaluate the impact of a vortex during the ejection period using VFM. Color Doppler images were obtained to produce VFM images in 80 subjects (20 normal, 29 with dilated cardiomyopathy, and 31 with old myocardial infarction). The duration of the LV vortex was measured and expressed as the ratio to the ejection time (VTRe). The VTRe showed significant correlations with EDV (ρ=0.672, p<0.001), ESV (ρ=0.772, p<0.001), EF (ρ=-0.783, p<0.001), left atrium diameter (LAd) (ρ=0.302, p=0.007), stroke volume (ρ=-0.600, p<0.001), e' (ρ=-0.389, p<0.001), a' (ρ=-0.314, p=0.005), s' (ρ=-0.512, p<0.001), and E/e' (ρ=0.330, p=0.003). The diastolic parameters (e', a', E/e', LAd) were not correlated when they were adjusted by EF. In the normal LV, a vortex existed for only a limited time during the early ejection period. In contrast, the lower the EF was, the longer the vortex remained during systole. Evaluation of vortices by VFM may noninvasively provide novel insights into the pathophysiology of impaired cardiac function.

Material ejection by the cold jets and temperature evolution of the south seasonal polar cap of Mars from THEMIS/CRISM observations and implications for surface properties

As the seasonal CO2 ice polar caps of Mars retreat during spring, dark spots appear on the ice in some specific regions. These features are thought to result from basal sublimation of the transparent CO2 ice followed by ejection of regolith‐type material, which then covers the ice. We have used Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) reflectance data, Thermal Emission Imaging System (THEMIS) visible images, and THEMIS‐derived temperature retrievals along with a thermal numerical model to constrain the physical and compositional characteristics of the seasonal cap for several areas exhibiting dark spots at both high spatial and temporal resolutions. Data analysis suggests an active period of material ejection (before solar longitude (Ls) 200), accumulation around the ejection points, and spreading of part of the ejected material over the whole area, followed by a period where no significant amount of material is ejected, followed by complete defrosting (≈ Ls 245). Dark material thickness on top of the CO2 ice is estimated to range from a few hundreds of microns to a few millimeters in the warmest spots, based on numerical modeling combined with the observed temperature evolution. The nature of the venting process and the amount of material that is moved lead to the conclusion that it could have an important impact on the surface physical properties.

Impact of levosimendan on right ventricular functions by using novel tissue Doppler derived indices in patients with ischaemic left ventricular failure

Right ventricular (RV) dysfunction complicates advanced left ventricular (LV) heart failure (HF) and contributes to a poor prognosis. Levosimendan is a positive inotropic agent improving cardiac contractility without increasing myocardial oxygen consumption in HF. To evaluate the effect of levosimendan therapy on RV systolic function, by using derived tissue Doppler imaging (TDI) in patients with ischaemic HF. The study consisted of 30 patients with HF who were admitted to our hospital due to new onset of decompensated HF, having LV ejection fraction < 40%, with functional status class III-IV, according to the New York Heart Association (NYHA). TDI-derived systolic velocities of tricuspid annulus (isovolumic myocardial acceleration [IVA], peak myocardial velocity during isovolumic contraction [IVV], peak systolic velocity during ejection period [Sa]) and diastolic indices (early [Ea] and late diastolic [Aa] velocities, Ea/Aa, E/Ea ratios and myocardial performance index [Tei index]) were measured. 72 hours after treatment, all measurements were re-evaluated. Considering TDI-derived systolic indices of the RV, IVA and IVV increased significantly, whereas Tei index decreased, after the therapy. Also, there was a significant decrease in serum levels of B-type natriuretic peptide. No significant change was observed in TDI derived diastolic indices of the RV. Levosimendan improves RV systolic function as expressed by TDI-derived parameters in patients with acutedecompensated HF.

Assessing right ventricular systolic function in a population of unselected patients before cardiac surgery: a multiparametric approach is mandatory

Background and aim: According to recent American guidelines, RV dysfunction can be diagnosed on a single parameter: 1) Peak systolic velocity during ejection period (S') <10 cm/sec 2) RV fractional area change (RVFAC) <35%. The aim of our study was to assess these recent recommendations in a large non-selected cohort of patients awaiting cardiac surgery and to evaluate less validated RV function criteria. Methods: Four hundred and thirteen patients (means values of age and LVEF respectively: 70.3±10.3 years and 62±13%) were enrolled of which 63% were awaiting valve surgery, 49% coronary artery bypass grafting and 3% others. To evaluate RV function, the following parameters were obtained: parameters derived from pulsed tissue Doppler at the tricuspid annulus (S', right myocardial performance index (RMPI), isovolumic acceleration (IVA)), RVFAC, and 2D Strain of the basal lateral wall. Indices of RV preload (IVC collapse index and right atrium RA area) and afterload (systolic pulmonary artery pressure, pulmonary vascular resistance) were also recorded. Results: Out of 413 patients, 320 patients (77.5%) had normal RV function (group 1, defined by S'>10cm/s and RVFAC> 35%,). RV dysfunction was probable in 54 patients (group 2, defined by S'<10cm/s OR RVFAC< 35%). RV dysfunction was highly probable in 39 patients (group 3, defined by S'<10cm/s AND RVFAC< 35%). Using group 1 and 3, other less-validated parameters were evaluated: IVA ≤1.8 m/s2 and basal 2D-Strain ≥-17% had both the best diagnostic value to detect RV dysfunction with a sensitivity of 86% and a specificity > 80%. A cut-off value of RMPI30.60 allowed an acceptable discrimination (AUC 0.79) to predict RV dysfunction with a specificity of 80%. Moreover, IVA was found to be the least load-dependent while basal 2D-Strain and RMPI appeared to be afterload and preload dependent. Conclusions: In patients with a suspicion of RV dysfunction, S' and RVFAC are frequently discordant (58% of the patients). Using a group of highly probable RV dysfunction (S'<10cm/s AND RVFAC< 35%), we found that IVA and basal 2D-Strain have both a good diagnostic value. Moreover, contrary to 2D-strain, IVA was not influenced by loading conditions, adding to its diagnostic value. Our results underline the need of a multiparametric approach to diagnose RV dysfunction, and for this setting both IVA and 2D strain could help.

The Impact of Blood Pressure on Carotid Artery Stiffness and Wave Intensity in Patients with Resistant Hypertension after Renal Sympathetic Denervation

Objective: The study investigated the impact of renal sympathetic denervation on office blood pressure and ambulatory blood pressure monitoring in patients with resistant hypertension. We evaluated whether a decrease in blood pressure may improve local carotid stiffness and parameters of wave intensity. Methods: Renal sympathetic denervation was performed in 17 patients (age 55 ± 9 years) with true resistant hypertension. Measurements of carotid stiffness and wave intensity were performed using ultrasound combined with echo-tracking. Results: We found significantly improved office systolic blood pressure changes 1 month (p=0.023) and together with pulse pressure changes at the 6 month follow up (p=0.041; p=0.016). Changes in systolic blood pressure during the daytime were significantly decreased at 1 month and diastolic blood pressure changes during the daytime were significantly reduced at 1 and 3 months. Stiffness parameters beta stiffness and pressure-strain elastic modulus were significantly reduced (p=0.04; p=0.03) and arterial compliance was increased (p=0.03), especially 1 and 3 months. The changes in negative area were significantly reduced after 1 month (p=0.041) and the ejection period was significantly increased at the 6 month follow-up (p=0.011). According to linear regression analysis systolic blood pressure correlated positively with the beta stiffness, pressure-strain elastic modulus, pulse wave velocity, and negatively with arterial compliance. Conclusions: We found significantly lower office blood pressure as well as blood pressure from ambulatory blood pressure monitoring in patients with resistant hypertension 6 months after renal sympathetic denervation. The decrease in blood pressure was followed by improvement of carotid stiffness and wave intensity. That may be reflected in enhancement of ventricular-arterial coupling.

Hemodynamics in the Cardiac Catheterization Laboratory of the 21st Century

There has been a striking evolution in the role of the cardiac catheterization laboratory over the past decades.1 In the 1950s and 1960s, hemodynamic assessment in the cardiac catheterization laboratory was essential for understanding the physiology and pathophysiology of patients with cardiovascular diseases. With the development of surgical interventions to treat patients with valvular and congenital heart disease, it became necessary for the cardiac catheterization laboratory to provide an accurate hemodynamic assessment, laying out a therapeutic road map. Nearly all patients who had open heart surgery underwent a complete hemodynamic catheterization before surgery. In the 1980s and 1990s, the evolution of 2-dimensional echocardiography and Doppler echocardiography provided an alternative noninvasive approach for the assessment of both cardiac anatomy and hemodynamics in patients with structural heart disease.2 By measuring blood flow velocities noninvasively, Doppler echocardiography was able to provide information on volumetric flow, intracardiac pressures, pressure gradients, and valve areas, as well as diastolic filling of the heart. Furthermore, noninvasive studies could be repeated easily, allowing the practitioner to follow the progress of his/her patient's condition longitudinally. At the same time, there was growing emphasis on coronary angiography for defining epicardial coronary disease with the subsequent development of interventional approaches for coronary disease with catheter-based therapies. As the major focus in the catheterization laboratory shifted to the diagnosis and treatment of the patient with acute and chronic coronary artery disease, the hemodynamic assessment of patients with structural heart disease was left to the noninvasive echocardiographic laboratory. As a consequence, many cardiac catheterization laboratories provided neither the training nor the expertise to assess hemodynamics properly. However, the advent of procedures such as balloon valvotomy, percutaneous valve implantation, and septal ablation has revived interest in structural heart disease and provided the invasive cardiologist with an armamentarium to treat patients who previously …

Assessing potential errors of MRI-based measurements of pulmonary blood flow using a detailed network flow model

MRI images of pulmonary blood flow using arterial spin labeling (ASL) measure the delivery of magnetically tagged blood to an image plane during one systolic ejection period. However, the method potentially suffers from two problems, each of which may depend on the imaging plane location: 1) the inversion plane is thicker than the imaging plane, resulting in a gap that blood must cross to be detected in the image; and 2) ASL includes signal contributions from tagged blood in conduit vessels (arterial and venous). By using an in silico model of the pulmonary circulation we found the gap reduced the ASL signal to 64-74% of that in the absence of a gap in the sagittal plane and 53-84% in the coronal. The contribution of the conduit vessels varied markedly as a function of image plane ranging from ∼90% of the overall signal in image planes that encompass the central hilar vessels to <20% in peripheral image planes. A threshold cutoff removing voxels with intensities >35% of maximum reduced the conduit vessel contribution to the total ASL signal to ∼20% on average; however, planes with large contributions from conduit vessels underestimate acinar flow due to a high proportion of in-plane flow, making ASL measurements of perfusion impractical. In other image planes, perfusion dominated the resulting ASL images with good agreement between ASL and acinar flow. Similarly, heterogeneity of the ASL signal as measured by relative dispersion is a reliable measure of heterogeneity of the acinar flow distribution in the same image planes.

Assessment of the hemodynamics of left ventricle in ventricular aneurysm during the contraction phase by vector flow mapping

Objective To evaluate the systolic function of left ventricle in myocardial infarction(MI)patients with ventricular aneurysm and the changing law of blood flow in ventricle with regional abnormality of wall movement by vector flow mapping (VFM).Methods Tirty-one MI patients with ventricular aneurysm and 35 healthy participants were enrolled in this study.The characteristic of vector and streamline,and the changing of the velocity gradient in left ventricular outflow tract (LVOT), and the average flow quantity through aneurysm neck were detected in the isovolumic contraction period, the rapid ejection period and the slow ejection period by VFM.Results The distinction between aneurysm and control group was mainly the persistance of vortex in aneurysm.The size of vortex in aneurysm was highly correlated with that measured by 2-D ultrasound(P ＜0.01).The percentage of vortex duration to cardiac cycle in patients group was significantly greater than that in control group(P ＜0.01).In the early systolic contraction the velocity gradient in LVOT in patients with ventricular aneurysm was smaller than that of control group(P ＜0.05).The average flow through aneurysm neck was notablely decreased compared with control group(P ＜0.01).Conclusions VFM can reveal the hemodynamics of left ventricle with aneurysm directly as well as quantitively measure the regional velocity and flow quantity.VFM can evaluate the systolic function of left ventricle exactly. Key words: Echocardiography ; Myocardial infarction; Heart aneurysm; Hemodynamic phenomena

Evaluation of ventricular functions using tissue Doppler echocardiography in patients with subclinical hypothyroidism

We evaluated right (RV) and left (LV) ventricle functions by tissue Doppler imaging (TDI) in patients with subclinical hypothyroidism (SH). Twenty-seven patients (24 women, 3 men; mean age 35.4±11.4 years) with newly diagnosed SH and 22 age- and sex-matched healthy subjects (20 women, 2 men; mean age 34.8±8.6 years) were evaluated by standard echocardiography and TDI. The diagnosis of SH was based on increased serum thyrotropin (TSH) level in the presence of normal free T3 and free T4 levels. The following TDI-derived parameters were measured: isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (S), and diastolic indices including peak early (E') and late (A') diastolic velocities, E'/A' and E/E' ratios, and myocardial performance index. Compared to healthy controls, patients with SH had higher LV mitral A velocity (p=0.022), lower E/A ratio (p=0.021), lower E' velocity (p=0.019), and higher E/E' ratio (p=0.017), suggesting significant LV diastolic dysfunction. The patient group also had lower IVV (p=0.004) and IVA (p<0.001), and higher isovolumic contraction time (p=0.012), suggesting LV subclinical systolic dysfunction. For RV parameters, decreased E/A ratio (p=0.014) and E' velocity (p=0.028) and increased isovolumic relaxation time (p=0.003) in SH patients were consistent with RV diastolic dysfunction, whereas parameters of RV systolic function were similar in the two groups. Myocardial performance indices of both ventricles were also significantly higher in the patient group (p<0.05). Our data suggest that SH is associated with biventricular systolic and diastolic dysfunction.

Evaluation of the eff ect of L-thyroxin therapy on cardiac functions by using novel tissue Doppler-derived indices in patients with subclinical hypothyroidism

Objectives Subclinical hypothyroidism (SH) is characterized by normal serum free T4 (fT4), free T3 (fT3) levels and increased serum thyroid stimulating hormone (TSH) levels. The aim of this study was to assess the validity of tissue Doppler imaging (TDI) in evaluating cardiac eff ects of SH and to demonstrate the improving eff ects of L-thyroxin(L-T4) on TDI parameters.Methods Twenty-seven patients with SH and 22 healthy controls were evaluated by standard echocardiography and TDI. TDI-derived systolic velocities [isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa)] and diastolic indices (peak early (Ea) and late diastolic (Aa) velocities, Ea/Aa, E/Ea ratios and Tei index) were measured. After restoring euthyroidism, all measurements were repeated.Results At baseline, left ventricular (LV) systolic velocities (IVV and IVA) and diastolic indices were signifi cantly impaired in the SH group. After L-T4 therapy, left ventricular systolic and diastolic functions were improved. Right ventricular (RV) systolic velocities were similar between the study group and the healthy controls but diastolic functions were impaired in the SH group, at baseline. Tei index of the RV was improved after L-T4 therapy. RV IVA remained unchanged after hormone replacement therapy.Conclusions SH is associated with biventricular systolic and diastolic dysfunction. IVA which is an accurate estimate of subclinical systolic dysfunction, was signifi cantly impaired in the left ventricle and had improved after L-T4 therapy. We found that IVA is able to detect early eff ects of subclinical hypothyroidism on LV systolic functions and L-T4 therapy can improve ventricular functions.

Hemodynamic Assessment of Severe Aortic Stenosis

Direct magnetic resonance imaging (MRI) planimetry of the maximal systolic aortic valve area does not consider temporal variations of the opening area during the ejection period. We evaluated an MRI-based methodology for the assessment of valvular dynamics in patients with severe aortic stenosis by measuring the systolic variability of the valvular blood stream, that is, the "vena contracta." With institutional review board approval, we examined 22 patients (13 male, 9 female; mean age, 68 ±10 years) with severe aortic stenosis using 1.5 T MRI and a standardized scanning protocol consisting of gradient-echo phase-contrast velocity imaging and steady-state free precession-cine MRI before and after valve replacement therapy. Temporal changes of the aortic valve area, represented by systolic variations of the area of poststenotic turbulent flow at its smallest convergence, that is, the proximal vena contracta, were determined by MRI and quantified by a calculated parameter of temporal valve dynamics (T). T was defined as the period which the aortic valve spent over its maximal opening area (>85%) during systole. MRI was also used to determine left ventricular hypertrophy before (LVMI) and its regression (LVMR) after valve replacement. Findings were compared with transthoracic echocardiography and cardiac catheterization. All patients had an echocardiographic effective orifice area, EOATTE, of <1.0 cm2. The comparison of T to LVMI and LVMR revealed significant correlations (LVMI: r = -0.62; P = 0.002; LVMR: r = 0.62; P = 0.002). Further significant correlations with aortic stenosis severity were observed in the comparison with manual planimetry, invasive measurements, and echocardiographic valve areas, as well as with pressure gradients. MRI can measure systolic variations of the aortic valve area. Quantitative parameters of the hemodynamic relevance of valve dynamics obtained by this method correlate with established parameters of aortic stenosis severity and LVMR.

Non-invasive ultrasound-based assessment of ventricular–arterial interaction in vascular Ehlers–Danlos syndrome patients

The role of ventricular–arterial hemodynamic interaction in the occurrence of arterial dissection and rupture in vascular Ehlers–Danlos syndrome (vEDS) is unknown. We recently introduced an ultrasound-based method to extract, from common carotid artery (CCA) diameter waveforms, central arterial properties and left ventricular (LV) systolic time intervals. We obtained CCA diameters, compliance and distensibility coefficients, and LV isovolumic contraction and ejection periods (ICP and EP) of 19 vEDS patients (aged 27–65 yrs) and 19 age-matched healthy controls. CCA distension and compliance tended to be lower in vEDS subjects ( p = 0.062 and p = 0.073), especially in younger patients. ICP (−12 ms) and EP (−24 ms) were shorter ( p < 0.001), while heart rate was increased (+10 bpm; p < 0.001) in vEDS. The ICP/EP ratio and estimated isovolumic d P LV/d t indicated increased LV contractility in vEDS. In conclusion, vascular EDS patients tend to have a lower CCA compliance but a normal pulse pressure, most likely reflecting reduced physical fitness.

Renal Dysfunction Does Not Affect the Peripheral-to-Central Arterial Pressure Transfer Function

Arterial generalized transfer functions (GTFs) are increasingly used to estimate central pressure from peripheral measurements. Analysis of derived central waveforms may be valuable in the assessment of patients with chronic kidney disease. The aim of this study was to assess whether the GTF is affected by renal disease. Ninety-four subjects with varying degrees of renal function (Kidney Disease Outcomes Quality Initiative stages 1 to 5; 14 controls) had simultaneous measurements of carotid and radial waveforms made by applanation tonometry. GTFs were calculated by Fourier analysis for each subject group. Derived carotid waveforms were obtained by applying an independently generated GTF to the radial waveform. Glomerular filtration rate inversely correlated with central systolic (R = -0.42; P < 0.001), mean (R = -0.34; P < 0.01) and diastolic (R = --0.27, P < 0.01) blood pressures, as well as central augmentation index (R = -0.30; P< 0.01) and carotid-femoral pulse wave velocity (R = -0.33; P < 0.001). Derived waveforms were not significantly different from measured waveforms in terms of systolic blood pressure, augmentation index, maximum slope, or the delay between the incident and reflected waves, although the derived waveforms slightly underestimated the systolic ejection period (-4.4 ± 0.9 ms; P < 0.001). Overall root-mean-square error was 2.4 ± 0.1 mm Hg. No significant relationship existed between the degree of bias of any derived waveform measure and glomerular filtration rate or chronic kidney disease stage (P > 0.16). No significant differences between chronic kidney disease stages were observed in transfer function gain or phase (P > 0.05). We conclude that the peripheral-to-central GTF is not affected by degree of renal dysfunction and can be used with equivalence in patients with varying degrees of chronic kidney disease.

Impact of Myocardial Acceleration during Isovolumic Contraction in Evaluating Subclinical Right Ventricular Systolic Dysfunction in Type 2 Diabetes Mellitus Patients

In diabetes mellitus (DM) patients, left ventricular dysfunction is widely evaluated and established by conventional diagnostic methods, whereas right ventricular (RV) function is not as sufficiently evaluated. The aim of this study is to assess the preclinical effects of DM on RV function by using novel Tissue Doppler Imaging (TDI)-derived indices. The study included 96 patients with type II DM [60 with DM only and 36 patients with coexisting DM and hypertension (DMHT)] and 40 healthy controls. Conventional parameters and TDI-derived systolic velocities of tricuspid annulus [isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), RV Tei index] were measured. TDI-derived RV IVA was significantly lower in both DM and DMHT patients compared to controls indicating subclinical impairment in RV systolic function in the study patients (P = 0,0001). However RV IVA was similar in DM and DMHT subgroup supporting RV systolic impairment in DM was independent from HT. In correlation analysis, RV IVA was significantly correlated with the existence of diabetic nephropathy (r =-0,38; P = 0,003), retinopathy (r =-0,35; P = 0,006), insulin resistance (r =-0,52; P = 0,0001). Diabetes is associated with subclinical RV systolic dysfunction, regardless of coexisting hypertension. Tissue Doppler-derived IVA; is a novel, non-invasive parameter which may be used in early detection of RV systolic dysfunction in patients with DM.

Double-Trouble Doppler: Reduction in Aortic Flow Due to Combined Left Ventricular Outflow Tract Obstruction and Severe Aortic Stenosis, Complete Diagnosis by Transthoracic Doppler Echocardiography

In patients with hypertrophic obstructive cardiomyopathy and dynamic left ventricular outflow tract obstructions, an additional fixed obstruction may uncommonly coexist. In these situations, flow through the aortic valve is usually delayed but typically still throughout the entire ejection period. We describe a case of marked reduction in aortic flow during mid and late systole, diagnosed by Doppler echocardiography, caused by combined hypertrophic obstructive cardiomyopathy and severe calcific bicuspid aortic stenosis.

Development and intra-institutional and inter-institutional validation of a comprehensive new hepatobiliary software: part 1 – liver and gallbladder function

To develop a software tool for quantification of liver and gallbladder function, and to assess the repeatability and reproducibility of measurements made with it. The software tool developed with the JAVA programming language uses the JAVA2 Standard Edition framework. After manual selection of the regions of interest on a 99mTc hepatic iminodiacetic acid study, the program calculates differential hepatic bile flow, basal duodeno-gastric bile reflux (B-DGBR), hepatic extraction fraction (HEF) of both the lobes with deconvolutional analysis and excretion half-time with nonlinear least squares fit. Gallbladder ejection fraction, ejection period (EP), ejection rate (ER), and postcholecystokinin (CCK) DGBR are calculated after stimulation with CCK-8. To assess intra-observer repeatability and intra-observer reproducibility, measurements from 10 normal participants were analyzed twice by three nuclear medicine technologists at the primary center. To assess inter-site reproducibility, measurements from a superset of 24 normal participants were also assessed once by three observers at the primary center and single observer at three other sites. For the 24 control participants, mean+/-SD of hepatic bile flow into gallbladder was 63.87+/-28.7%, HEF of the right lobe 100+/-0%, left lobe 99.43+2.63%, excretion half-time of the right lobe 21.50+6.98 min, left lobe 28.3+/-11.3 min. Basal DGBR was 1.2+/-1.0%. Gallbladder ejection fraction was 80+/-11%, EP 15.0+/-3.0 min, ER 5.8+/-1.6%/min, and DGBR-CCK 1.3+/-2.3%. Left and right lobe HEF was virtually identical across readers. All measures showed high repeatability except for gallbladder bile flow, basal DGBR, and EP, which exhibited marginal repeatability. Ejection fraction exhibited high reproducibility. There was high concordance among the three primary center observers except for basal DGBR, EP, and ER. Concordance between the primary site and one of the other sites was high, one was fair, and one was poor. New United States Food and Drug Administration-approved personal computer-based Krishnamurthy Hepato-Biliary Software for quantification of the liver and gallbladder function shows promise for consistently repeatable and reproducible results both within and between institutions, and may help to promote universal standardization of data acquisition and analysis in nuclear hepatology.

OP04.08: Direct 4D-MPI in fetuses with evolving cardiac compromise

Modified myocardial performance index (Mod-MPI) is an accepted method of cardiac performance evaluation in children, adults and fetuses based on Doppler flow evidence of opening and closing of the AV and semilunar valves. We demonstrated 4D-MPI, based on analysis of STIC-acquired volume sets for direct visualization of opening and closing of the valves and assessment of the isovolumetric and ejection periods. We applied 4D-MPI to the evaluation of pathological cases with suspected or developing cardiac compromise and compared these results with Mod-MPI and normal 4D-MPI nomograms. Gravidae referred for evaluation of fetal pathologies with suspicion of cardiac compromise were examined with 2DUS parameters as indicated, including Mod-MPI. 4D-MPI was obtained in post-processing from saved STIC volumes. In multiplanar mode in post-processing, isovolumetric and ejection periods were measured according to valve status. 4D-MPI results were compared to conventional Mod-MPI. 30 healthy fetuses were examined to establish normal range of values for 4D-MPI at 24–32 weeks. MPI measured in both methods remained relatively stable during pregnancy. In 13 cases of evolving cardiac compromise (agenesis of ductus venosus with extra-hepatic connection-4, cardiomyopathy-2, SVT-2, diaphragmatic hernia-1, fetal anemia [before treatment]-2, pulmonary-venous shunt-1, CMV infection-1), conventional Mod-MPI and 4D-MPI showed similar results. The difference between them did not exceed ± 0.05 (clinically insignificant). 4D-MPI is useful for direct evaluation of fetuses with suspected cardiac compromise, and provided results comparable to those obtained with conventional Mod-MPI. 4D-MPI may form part of the 3D/4DUS exam performed on these fetuses.

Are measurements of systolic myocardial velocities and displacement with colour and spectral Tissue Doppler compatible?

BackgroundTissue Doppler (TD) in pulsed mode (spectral TD) and colour TD are the two modalities today available in tissue velocity echocardiography (TVE). Previous studies have shown poor agreement between these two methods when measuring myocardial velocities and displacement. In this study, the concordance between the myocardial velocity and displacement measurements using colour TD and different spectral TD procedures was evaluated.MethodsLeft ventricular (LV) longitudinal systolic myocardial velocities and displacement during ejection period were quantified at the basal septal and lateral wall in 24 healthy individuals (4 women and 20 men, 34 ± 12 years) using spectral TD, colour TD and M-mode recordings. Mean, maximal and minimal spectral TD systolic velocities and the corresponding displacement values were obtained by measurements at the outer and inner borders of the spectral velocity signal. The results were then compared with those obtained with the two other modalities used.ResultsSystolic myocardial velocities derived from mean spectral TD frequencies were highly concordant with corresponding colour TD measurements (mean difference 0.10 ± 0.54 cm/sec in septal and 0.09 ± 0.97 cm/sec in lateral wall). Similarly, the agreement between spectral and colour TD (mean difference 0.22 ± 0.74 mm in septal and 0.02 ± 0.86 mm in lateral wall) as well as M-mode was good when mean spectral velocities were temporally integrated and the results did not differ statistically. Conversely, displacement values from the inner or outer border of the spectral signal differed significantly from values obtained with colour TD and M-mode (p < 0.001, in both cases).ConclusionLV systolic myocardial measurements based on mean spectral TD frequencies are highly concordant with those provided by colour TD and M-mode. Hence, in order to maintain compatibility of the results, the use of this particular spectral TD procedure should be advocated in clinical praxis.

A preliminary study on the evaluation of relationship between left ventricular torsion and cardiac cycle phase by two-dimensional ultrasound speckle tracking imaging

In normal subjects there is a certain corresponding relationship between the peak rotation angle of the apex and the base with respect to the phase of the cardiac cycle. We hypothesized that the myocardial contractile force and the delay of conduction may affect the correspondence of them. Our study aims to use speckle tracking imaging (STI) technique to analyze the relationship between the left ventricular rotation/torsion (LVrot/ LVtor ) characteristics and cardiac cycle phase, to investigate its clinical feasibility. The echocardiographic images of the short-axis view of the left ventricles (LV) at the apical and basal planes were acquired by STI in 32 healthy controls and 48 heart failure patients (New York Heart Association class I or II). LVtor angle, LVrot angle, the peak value and time of LVtor and LVrot were measured offline using frame-to-frame tracking of gray-scale speckle patterns at the standardized time point, respectively. All the acquired data of the two groups were compared and analyzed. In the healthy controls, there was no significant difference among the isovolumetric contraction time, peak time of clockwise rotation at the apical level and the peak time of clockwise rotation at the basal level segments (P > 0.05). There was no significant difference among systolic time, peak time of counterclockwise rotation at the apical level and peak time of counterclockwise rotation at the basal level segments (P > 0.05). There was no significant difference between systolic time and peak time of LVtor (P > 0.05). Compared with normal group, the peak of LVtor and LVrot angle were decreased at both apical and basal planes in heart failure group (P < 0.05). The peak time of LVtor was delayed in heart failure group (P < 0.05). The peak time of clockwise rotation at the apical level segments was longer than control group (P < 0.05) and continued to the ejection period. In the normal subjects, there is no sequence difference of LVrot between the basal and apical planes. They were correspondent to cardiac cycle. There is a temporal sequence difference of LVrot between basal and apical planes during LV contraction in heart failure group and decreased LVtor/rot have been demonstrated to influence left ventricular function. STI has shown great potential in early detecting the conduction variability in ventricular wall.

Analysis of the Origin of Cardiac Wall Motion that Constitutes Myocardial Velocity-Time Curves in Patients with Left Bundle Branch Block

Septal and lateral wall myocardial velocity-time curves from tissue Doppler imaging were analyzed to determine wall motion from which the velocity originated in 34 patients with left bundle branch and systolic dysfunction (ejection fraction < 45%). Longitudinal strain rate by speckle tracking imaging was assessed to identify whether corresponding wall motion was active or passive. All lateral peak velocities during the ejection period were derived from delayed active movement. However, septal peak velocities were more numerous and complex. Septal peak velocities during pre-ejection were derived from the first active movement in 29 patients (85.2%). Septal peak velocities during the ejection period were derived from the second active movement in 20 patients, passive movement in 9 patients, and first active movement in 5 patients. Because septal peak velocities were consistent with various wall motion types, identification of the origin of septal peak velocities, including during pre-ejection, may be important in identifying LV dyssynchrony based on the propagation of first active myocardial movements.