End Systole Research Articles

Cardiovascular magnetic resonance of cardiac morphology and function: impact of different strategies of contour drawing and indexing.

Cardiovascular magnetic resonance (CMR) is the gold standard for the quantitative assessment of cardiac volumes, mass and function. There are, however, various strategies for establishing endocardial borders, the cardiac phase used for measurements and the body dimensions used for indexing these results. The aim of the study was to assess the impact of different strategies on reference values. 362 healthy volunteers (190 men, mean age 51 ± 13years) underwent a standard CMR protocol. Left ventricular end-diastolic (LV-EDV) and end-systolic (LV-ESV) volumes and LV mass (LV-M) were measured at end systole and end diastole in SSFP sequences using two methods, one of which included papillary muscles and trabecular tissue in the LV-M ("include" approach), while the other excluded this tissue ("exclude" approach). There was a strong correlation between the results for LV volumes and LV ejection fraction (LV-EF) between the "include" and the "exclude" approach, while the mean values were different: LV-EDV: 149.7 ± 32.5ml vs 160.5 ± 35.0ml, p < 0.0001; LV-ESV: 48.7 ± 14.5ml vs 56.4 ± 16.7ml, p < 0.0001; LV-EF: 67.7 ± 5.4% vs 65.1 ± 5.6%, p < 0.0001. When comparing end-systolic with end-diastolic data, values for LV-M were significantly higher in end systole irrespective of whether papillary muscles and trabecular tissues were included or not. Furthermore, LV-M missed overweight-induced LV hypertrophy when indexed to body surface area (BSA) instead of height. Quantitative assessment of LV volumes and mass with inclusion of papillary muscles and trabeculae to myocardial mass resulted in significantly different values, while indexing to BSA and not height may miss LV hypertrophy in terms of overweight.

Effects of captopril and valsartan on ventricular remodeling and inflammatory cytokines after interventional therapy for AMI.

The effects of captopril and valsartan on ventricular remodeling and inflammatory cytokines after interventional therapy for acute myocardial infarction (AMI) were investigated. A total of 94 patients with AMI admitted to Honggang Hospital of Dongying from July 2016 to June 2017 were selected as study subjects. The patients were treated with interventional therapy and randomly divided into the observation group (n=47) and the control group (n=47). The control group received aspirin after operation, while the observation group received captopril and valsartan after operation. Three-dimensional ultrasonography was performed to evaluate ventricular remodeling. The related parameters included left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), end-systolic sphericity index/end-diastolic sphericity index (ESSI/EDSI), systolic dyssynchrony index (SDI), diastolic dyssynchrony index (DDI), dispersion end systole (DISPES), DDI-late and DISPED-late. The levels of inflammatory cytokines were determined by enzyme-linked immunosorbent assay (ELISA). The incidence of adverse reactions after treatment was compared. After treatment, LVEF in the control group was significantly lower than that in the observation group, while LVEDV, LVESV and the ratio of early diastolic (E) and late diastolic (A) (E/A) in the control group were significantly higher than those in the observation group (p<0.05). EDSI, DDI-late and DISPED-late in the control group were significantly higher than those in the observation group (p<0.05). ESSI, SDI and DISPES in the control group were significantly higher than those in the observation group (p<0.05). The levels of interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor-α (TNF-α) in the observation group were significantly lower than those in the control group at 1, 4 and 8 weeks after treatment (p<0.05). The administration of captopril and valsartan after interventional therapy for AMI can effectively improve the cardiac function of patients, improve the synchronism of left ventricular diastole and contraction, and reduce the level of inflammation. It is safe and reliable, and has important clinical significance.

Quantitative Assessment of the Effect of the Out-of-Plane Movement of the Homogenous Ellipsoidal Model of the Left Ventricle on the Deformation Measures Estimated Using 2-D Speckle Tracking-An In-Silico Study.

Effect of the out-of-plane (OOP) movement amplitude on estimates of global displacements (radial, circumferential) and strains (radial , circumferential ) was studied in an ellipsoidal model of the left ventricle using finite-element modeling (FEM), synthetic ultrasonic data, and short-axis view. This effect was assessed using median of the absolute relative error (RE) of the global parameters. FEM provided node displacements for synthetic ultrasonic data and reference data generation. Displacements were estimated using block-matching (BM) and B-spline (BS) methods. FEM-derived data analysis, free from errors resulting from speckle tracking, indicated that the tissue motion introduced REs of global strain estimates below 4.5%. The effect of the OOP motion amplitude on strain estimates was strain specific and depended on the displacement estimation method. In the case of , the increase of the OOP amplitude resulted in quasi-linear increase of the RE from approximately 10% to 15%. The modulus of the end-systolic (ES) errors of the estimates almost linearly increased with increasing OOP amplitude approximately from 10% to 16%. REs of the estimate were close to 80% and 40%, respectively, in the case of the BM and BS methods, and increased with increasing OOP amplitude. The modulus of the ES errors of the estimates in the case of the BS method was about -40% and showed low sensitivity to the OOP amplitude; in the BM case, these errors varied approximately from -70% to -58% for OOP amplitude from 0 to 15 mm.

A Novel 4D Semi-Automated Algorithm for Volumetric Segmentation in Echocardiography.

Segmentation of the left ventricle (LV) in temporal 3D echocardiography sequences poses a challenge. However, it is an essential component in generating quantitative clinical measurements for the diagnosis and treatment of various cardiac diseases. Identifying the endocardial borders of the left ventricle can be difficult due to the inherent properties of ultrasound. This study proposes a 4D segmentation algorithm that segments over temporal 3D volumes that has minimal user interaction and is based on a diffeomorphic registration approach. In contrast to several existing algorithms, the proposed method does not depend on training data or make any geometrical assumptions. The algorithm was evaluated on seven patients obtained from the Mazankowski Alberta Heart Institute, Edmonton, Canada in comparison to expert manual segmentation. The proposed approach yielded Dice scores of 0.94 (0.01), 0.91 (0.03) and 0.92 (0.02) at end diastole, at end systole and over the entire cardiac cycle, respectively. The corresponding Hausdorff distance values were 4.49 (1.01) mm, 4.94 (1.41) mm, and 5.05 (0.85) mm, respectively. These results demonstrate that the proposed 4D segmentation approach for the left ventricle is robust and can potentially be used in clinical practice.

Association between epicardial adipose tissue, high-sensitivity C-reactive protein and myocardial dysfunction in middle-aged men with suspected metabolic syndrome

BackgroundAs body fat composition and metabolism differ between men and women, we evaluated sex-related differences in the association among epicardial adipose tissue (EAT), secretome profile, and myocardial function of subjects with suspected metabolic syndrome.MethodsWe evaluated 277 participants (men, n = 140; 56.1 ± 4.7 years) who underwent conventional echocardiography and two-dimensional speckle tracking from the Seoul Metabolic Syndrome cohort. EAT was measured from the right ventricular free wall perpendicular to the aortic annulus at end systole. Global longitudinal strain (GLS) was obtained from 18 apical segments. Apolipoprotein A1, apolipoprotein B, adiponectin, and high-sensitivity C-reactive protein (hs-CRP) levels were measured using immunoturbidimetry assay.ResultsMean age, body mass index, and hs-CRP level did not differ by sex. Waist circumference, fasting blood glucose level, and triglyceride/high-density lipoprotein cholesterol ratio were higher, and apolipoprotein AI and adiponectin levels were lower in men. No significant difference in mean EAT thickness was found (7.02 ± 1.81 vs. 7.13 ± 1.70 mm, p = 0.613). Men had a higher left ventricular (LV) mass index and lower GLS. EAT thickness was associated with hs-CRP level in men alone (ß = 0.206, p = 0.015). LV mass index (ß = 2.311, p = 0.037) and function represented by e′ (ß = − 0.279, p = 0.001) and GLS (ß = − 0.332, p < 0.001) were independently associated with EAT thickness in men alone.ConclusionsIn middle-aged subjects with suspected metabolic syndrome, EAT was associated with inflammation represented by hs-CRP level, LV mass, and subclinical myocardial dysfunction only in men, suggesting that the inflammatory activity of EAT induced myocardial remodeling and dysfunction in middle-aged subjects but was attenuated in women.Trial registration NCT02077530 (date of registration: November 1, 2013)

Association of Circulating Adipokines With Echocardiographic Measures of Cardiac Structure and Function in a Community-Based Cohort.

BackgroundAdipokines mediate cardiometabolic risk associated with obesity but their role in the pathogenesis of obesity‐associated heart failure remains uncertain. We investigated the associations between circulating adipokine concentrations and echocardiographic measures in a community‐based sample.Methods and ResultsWe evaluated 3514 Framingham Heart Study participants (mean age 40 years, 53.8% women) who underwent routine echocardiography and had select circulating adipokines measured, ie, leptin, soluble leptin receptor, fatty acid–binding protein 4, retinol‐binding protein 4, fetuin‐A, and adiponectin. We used multivariable linear regression, adjusting for known correlates (including weight), to relate adipokine concentrations (independent variables) to the following echocardiographic measures (dependent variables): left ventricular mass index, left atrial diameter in end systole, fractional shortening, and E/e′. In multivariable‐adjusted analysis, left ventricular mass index was inversely related to circulating leptin and fatty acid–binding protein 4 concentrations but positively related to retinol‐binding protein 4 and leptin receptor levels (P≤0.002 for all). Left atrial end‐systolic dimension was inversely related to leptin but positively related to retinol‐binding protein 4 concentrations (P≤0.0001). E/e′ was inversely related to leptin receptor levels (P=0.0002). We observed effect modification by body weight for select associations (leptin receptor and fatty acid–binding protein 4 with left ventricular mass index, and leptin with left atrial diameter in end systole; P<0.05 for interactions). Fractional shortening was not associated with any of the adipokines. No echocardiographic trait was associated with fetuin‐A or adiponectin concentrations.ConclusionsIn our cross‐sectional study of a large, young to middle‐aged, relatively healthy community‐based sample, key indices of subclinical cardiac remodeling were associated with higher or lower circulating concentrations of prohypertrophic and antihypertrophic adipokines in a context‐specific manner. These observations may offer insights into the pathogenesis of the cardiomyopathy of obesity.

Effects of hydrogel injection on borderzone contractility post-myocardial infarction.

Injectable hydrogels are a potential therapy for mitigating adverse left ventricular (LV) remodeling after myocardial infarction (MI). Previous studies using magnetic resonance imaging (MRI) have shown that hydrogel treatment improves systolic strain in the borderzone (BZ) region surrounding the infarct. However, the corresponding contractile properties of the BZ myocardium are still unknown. The goal of the current study was to quantify the in vivo contractile properties of the BZ myocardium post-MI in an ovine model treated with an injectable hydrogel. Contractile properties were determined 8 weeks following posterolateral MI by minimizing the difference between in vivo strains and volume calculated from MRI and finite element model predicted strains and volume. This was accomplished by using a combination of MRI, catheterization, finite element modeling, and numerical optimization. Results show contractility in the BZ of animals treated with hydrogel injection was significantly higher than untreated controls. End-systolic (ES) fiber stress was also greatly reduced in the BZ of treated animals. The passive stiffness of the treated infarct region was found to be greater than the untreated control. Additionally, the wall thickness in the infarct and BZ regions was found to be significantly higher in the treated animals. Treatment with hydrogel injection significantly improved BZ function and reduced LV remodeling, via altered MI properties. These changes are linked to a reduction in the ES fiber stress in the BZ myocardium surrounding the infarct. The current results imply that injectable hydrogels could be a viable therapy for maintaining LV function post-MI.

Risk Marker Variability in Subclinical Carotid Plaques Based on Ultrasound is Influenced by Cardiac Phase, Echogenicity and Size

Identification of risk markers based on quantitative ultrasound texture analysis of carotid plaques has the ability to define vulnerable components that correlate with increased cardiovascular risk. However, data describing factors with the potential to influence the measurement variability of risk markers are limited. The aim of this study was to evaluate the influence of electrocardiogram-guided image selection, plaque echogenicity and area on carotid plaque risk markers and their variability in asymptomatic carotid plaques. Plaque risk markers were measured in 57 plaques during three consecutive heartbeats at two cardiac cycle time instants corresponding to the electrocardiogram R-wave (end diastole) and end of T-wave (end systole), resulting in six measurements for each plaque. Risk marker variability was quantified by computing the coefficient of variation (CV) across the three heartbeats. The CV was significantly higher for small plaques (area <15 mm2, 10%) than for large plaques (area >15 mm2, 6%) (p < 0.001) in measurements of area, and the CV for measurements of gray-scale median were higher for echolucent plaques (<40, 15%) than for echogenic plaques (>40, 9%) (p < 0.001). No significant differences were found between systole and diastole for the mean of any risk marker or the corresponding CV value. However, in a sub-analysis, the echolucent plaques were found to have a higher CV during systole compared with diastole. The variability also caused plaque type reclassification in 16% to 25% of the plaques depending on cutoff value. The results of this study indicate that echolucent and small plaques each contribute to increased risk marker variability. Based on these results, we recommend that measurements in diastole are preferred to reduce variation, although we found that it may not be possible to characterize small plaques accurately using contemporary applied risk markers.

Definition of the margin of major coronary artery bifurcations during radiotherapy with electrocardiograph-gated 4D-CT

PurposeThe aim was to measure the cardiac motion-induced displacements of major coronary artery bifurcations utilizing electrocardiography (ECG)-gated four-dimensional computed tomography (4D-CT) and to determine the margin of coronary artery bifurcations. MethodsThirty-seven female patients who underwent retrospective ECG-gated 4D-CT in inspiratory breath hold (IBH) were enrolled. The left main coronary artery bifurcation (LM), the obtuse marginal branch bifurcation (OM), the first diagonal branch bifurcation (D1), the second diagonal branch bifurcation (D2), the caudal portion of the left anterior descending branch (APX), the first right ventricular artery bifurcation (V) and the acute marginal branch bifurcation (AM) were contoured. The center of the contour of the coronary arterial bifurcations at end systole was defined as the standard, and the margin were then calculated. ResultsThe margin in the left–right (LR), cranio-caudal (CC), and anterior-posterior (AP) coordinates were as follows: LM 3, 3, and 3 mm; D1 6, 3, and 3 mm; D2 3, 3, and 3 mm; APX 4, 4, and 4 mm; OM 4, 6, and 5 mm; V 6, 8, and 7 mm; and AM 6, 8, and 7 mm, respectively. ConclusionCoronary artery bifurcations should be considered a separate organ at risk (OAR), and different margin should be provided due to the differences resulting from motion displacement. The maximum margin in the LR, CC, and AP coordinates of left coronary artery bifurcations were 6, 6, and 5 mm, and those of the right coronary artery bifurcations were 6, 8, and 7 mm, respectively.

Effect of down-regulation of IKs repolarization-reserve on ventricular arrhythmogenesis in a guinea pig model of cardiac hypertrophy

To observe the changes of rapidly activated delayed rectifier potassium channel (IKr) and slowly activated delayed rectifier potassium channel (IKs) in cardiac hypertrophy and to evaluate the effects of IKr and IKs blocker on the incidence of ventricular arrhythmias in guinea pigs with left ventricular hypertrophy (LVH). Methods: Guinea pigs were divided into a sham operation group and a left ventricular hypertrophy (LVH) group. LVH model was prepared. Whole cell patch-clamp technique was used to record IKr and IKs tail currents in a guinea pig model with LVH. The changes of QTc and the incidence rate of ventricular arrhythmias in LVH guinea pigs were observed by using the IKr and IKs blockers. Results: Compared with cardiac cells in the control group, the interventricular septal thickness at end systole (IVSs), left ventricular posterior wall thickness at end systole (LVPWs), QTc interval and cell capacitance in guinea pigs with LVH were significantly increased (P<0.05); while IKs densities were significantly reduced [+60 mV: (0.36±0.03) pA/pF vs (0.58±0.05) pA/pF, P<0.01]. However, LVH exerted no significant effect on IKr densities. IKr blocker markedly prolonged the QTc interval (P<0.01) and increased the incidence of ventricular arrhythmias in guinea pigs with LVH compared with the control guinea pigs. In contrast, IKs blocker produced modest increase in QTc interval in guinea pigs of control group with no increase in LVH animals. IKs blocker did not induce ventricular arrhythmias incidence in either control or LVH animals. Conclusion: The cardiac hypertrophy-induced arrhythmogenesis is due to the down-regulation of IKs.

Development and clinical validation of a hybrid method for semiautomated left ventricle endocardial and epicardial boundary extraction on cine-magnetic resonance images.

We describe a hybrid method for left ventricle (LV) endocardial and epicardial segmentation on cardiac magnetic resonance (CMR) images requiring minimal operator intervention. Endocardium extraction results from the union of three independent estimations based on adaptive thresholding, region growing, and active contour with Chan-Vese energy function. Epicardium segmentation relies on conditional morphological dilation of the endocardial mask followed by active contour optimization. The proposed method was first evaluated using an open access database of 18 CMR for which expert manual contouring was available. The method was further validated on a retrospective cohort of 29 patients, who underwent CMR with expert manual segmentation. Regarding the open access database, similarity (Dice index) between hybrid and expert segmentations was good for end-diastolic (ED) endocardium (0.92), end-systolic (ES) endocardium (0.88), and ED epicardium (0.92). As for derived LV parameters, concordance (Lin's coefficient) was good for ED volume (0.91), ES volume (0.93), ejection fraction (EF; 0.89), and fair for myocardial mass (MM; 0.74). Regarding the retrospective patient study, concordance between expert and hybrid estimations was excellent for ED volume (0.95), ES volume (0.96), good for EF (0.86), and fair for MM (0.71). Hybrid segmentation resulted in small biases ([Formula: see text] for ED volume, [Formula: see text] for ES volume, [Formula: see text] for EF, and [Formula: see text] for MM) with little clinical relevance and acceptable for routine practice. The quickness and robustness of the proposed hybrid method and its ability to provide LV volumes, functions, and masses highly concordant with those given by expert segmentation support its pertinence for routine clinical use.

In Utero Exposure To Cigarette Smoke Promotes Cardiac Dysfunction In High‐fat Fed Mice

Maternal smoking during pregnancy is associated with an increased risk for metabolic syndrome, a risk factor for heart disease. In this study, we investigated whether in utero exposure to second hand cigarette smoke would adversely affect cardiac structure/function in the exposed offspring fed a high‐fat diet. Pregnant mice (C57B1/6J) were exposed to cigarette smoke or air (4 hr/d) on gestational days 6–19. The male offspring (age: 35 days) from the smoke and air exposure groups were fed either normal chow, or high‐fat liquid diet (35% of fat; HFD) for 16 weeks (n=12/group). Cardiac function was measured by echocardiography at baseline (30 days) and at the end of pair feeding. Mice were then sacrificed and heart tissue collected for histological analysis. At baseline, left ventricular internal diameter at end systole was significantly greater in the smoke‐exposed compared to the air group (3.2±0.1 vs 2.8±0.1 mm, P&lt;0.05). All other baseline echocardiographic parameters were similar between the groups. 16 weeks of HFD feeding significantly increased the body weight and heart weight/tibial length in both the air and smoke‐exposed mice (P&lt;0.05, smoking+HFD vs. smoking+chow; air+HFD vs. air+chow). However, there was no significant difference in body weight or heart weigh/tibial length between the smoking+HFD and air+HFD groups. Compared to air+HFD mice, smoking+HFD mice had significantly decreased left ventricular internal diameters and volumes during diastole (3.95±0.09 vs. 4.34±0.24 mm; 67.8±1.5 vs. 85.4±4.4 μl, P&lt;0.05) and systole (2.91±0.07 vs. 3.34±0.15 mm; 32.5±1.9 vs. 46.3±5.1 μl, P&lt;0.05), accompanied by increases in left ventricular wall during diastole (0.72±0.03 vs. 0.66±0.03 mm, P&lt;0.01) and septal thickness during systole (1.2±0.06 vs. 0.99±0.05 mm, P&lt;0.05) and increased fractional shortening. There was also increased collagen in the hearts of the smoking+HFD mice. These data indicate the development of concentric cardiac hypertrophy in smoking+HFD mice. We conclude that in utero exposure to second hand cigarette smoke produces differential cardiac responses following challenge with obesogenic high fat diet.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

What the Current Arterial‐Ventricular Coupling Index Fails to Tell Us

BACKGROUNDThe arterial‐ventricular (AV) coupling index (k) is often employed to evaluate ventricular performance in relation to arterial properties. The index k is defined as the ratio of end‐systolic (ES) ventricular elastance (Emax) and effective arterial elastance (Ea). Emax describes the nonlinear trajectory of ventricular pressure (P) and volume (V) at end‐systole. Within a sufficiently small range Emax may be approximated by ESP/(ESV − Vo), where Vo is the extrapolated volume axis intercept. Likewise Ea is defined as ESP/SV, where SV is stroke volume. It may be convenient to index (i) volumes for body surface area (BSA). However, in the formula for k, both ESP and BSA cancel out, resulting in a dimensionless index. Unfortunately, the term Vo is neglected in most studies.AIMSThis investigation addresses the question if AV coupling can be described completely by k, or if an additional cofactor (kc) may be necessary, regardless of inclusion of Vo or not.METHODSSince k concerns a ratio, information is lost compared to the constitutive details available, namely SV and (ESV‐Vo). Plotting SV vs (ESV‐Vo) shows k as the tangent, while the missing companion of k (here termed kc) can be identified as the distance from the origin. The Pythagorean theorem states that kc equals the root of the sum of SV and (ESV‐Vo) each squared. We calculated the possible association between k and kc for published data (Asanoi et al., Circ Res 1989;65: 483–493) on 12 healthy individuals and 16 patients with cardiac dysfunction including heart failure. In their study Emax and Vo were obtained via linear regression analysis on more than 5 data points obtained by combined 2D echocardiography and variation of ESP as induced by phenylephrine and sodium nitroprusside i.v., respectively. While omitting Vo (indicated by the prime for k and kc), we also calculated k′ and kc′.RESULTSAlthough there is an association k′ = 0.486 k + 0.4861, R2 = 0.3928 (P&lt;0.001), N=28, the connection strongly diverges for k&gt;1, where a value between 1 and 2 is supposed to correspond with optimal matching. The kc relates to k via kc = −17.22 ln (k) + 71.57, R2 = 0.384, N=28, and likewise kc′ to k′ as kc′ = −31.81 ln (k′) + 77.96, R2 = 0.624, N=28.CONCLUSIONSThe dimensionless metric k is only characterized by SV, ESV and Vo, not by end‐systolic pressure level. The companion kc depends on the same variables, and has the dimension of volume (index). AV‐coupling is more completely characterized by the combination of k and kc. Consideration of the value of k in isolation provides an incomplete description of AV‐coupling characteristics, regardless of the fact whether Vo is included.Support or Funding InformationnoneThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Assessment of epicardial fat and carotid intima media thickness in gestational hypertension.

Gestational hypertension (GHT) is a common disorder of pregnancy characterized by new onset hypertension without the presence of detectable proteinuria after 20 weeks of gestation. Epicardial fat thickness (EFT) and carotid intima media thickness (CIMT) are suggested as new predictors of subclinical atherosclerosis. Although the relationship between these parameters and essential hypertension has been demonstrated, this association in patients with GHT is still unknown. We aimed to investigate CIMT and EFT in patients with GHT. A total of 90 patients (44 GHT and 46 controls) were enrolled. Patients with diabetes mellitus, chronic hypertension and cardiovascular disease (CVD) were excluded. In the third trimester, the mean CIMT at the far wall of both left and right common carotid arteries was measured on B-mode duplex ultrasound. EFT was measured on the free wall of the right ventricle at the end systole in the parasternal long-axis view by standard transthorasic 2D echocardiography. Unlike the mean CIMT (0.52 ± 0.13 mm vs 0.47 ± 0.11 mm; P = 0.078), the mean EFT was significantly higher in the GHT group compared to the controls (5.31 ± 1.68 mm vs 4.17 ± 1.16 mm; P = 0.002). In multivariate logistic regression analysis, among the most pertinent clinical variables, only EFT is an independent determinant of GHT (OR: 2.903; 95% confidence interval [CI]: 1.454-5.796; P = 0.003). In receiver operating characteristic (ROC) analysis, EFT >5.5 mm had 82.6% specificity and 52.3% sensitivity in predicting a diagnosis of GHT (ROC area under curve: 0.689, 95% CI: 0.577-0.802, P = 0.002). Maternal EFT may be higher in pregnant women with GHT in comparison with those of controls.

Relation Between Wrist Circumference and Left Ventricular Structure in Overweight Children

The aim of this study was to assess the relation of wrist circumference with changes in left ventricular (LV) structure in a population of overweight/obese children and adolescents. One hundred and six children and adolescents were consecutively enrolled. In all subjects body weight, height, wrist circumference, waist circumference, body mass index-standard deviation score, fasting glucose, insulin, lipid profile, and blood pressure were evaluated. All subjects underwent echocardiographic assessment, and the following parameters were evaluated: LV dimension at end diastole and LV dimension at end systole, LV posterior wall thickness at end diastole and LV posterior wall thickness at end systole, interventricular septal thickness at end diastole and interventricular septal thickness at end systole, LV mass, and epicardial adipose tissue (EAT). LV hypertrophy was defined as LVM Index ≥95th percentile. Wrist circumference correlated with all parameters of LV dimensions and LV mass (p <0.0001) and EAT (p = 0.04). The strongest correlations were reported between wrist circumference with LV dimension at end diastole and LV dimension at end systole (r = 0.73 and r = 0.68 respectively, p <0.0001, for both). Results of the multivariate regression analysis showed that wrist circumference was significantly associated with all parameters of LV dimensions, LV mass, and EAT (p ≤0.002). The logistic regression showed that wrist circumference was significantly associated with LV hypertrophy (odds ratio 1.39, p = 0.046). In conclusion, wrist circumference could be a useful measure of cardiovascular risk in obese children and adolescents, opening new perspectives in the prediction of cardiovascular diseases.

Precision of regional wall motion estimates from ultra-low-dose cardiac CT using SQUEEZ

Resting regional wall motion abnormality (RWMA) has significant prognostic value beyond the findings of computed tomography (CT) coronary angiography. Stretch quantification of endocardial engraved zones (SQUEEZ) has been proposed as a measure of regional cardiac function. The purpose of the work reported here was to determine the effect of lowering the radiation dose on the precision of automatic SQUEEZ assessments of RWMA. Chronic myocardial infarction was created by a 2-h occlusion of the left anterior descending coronary artery in 10 swine (heart rates 80-100, ejection fraction 25-57%). CT was performed 5-11 months post infarct using first-pass contrast enhanced segmented cardiac function scans on a 320-detector row scanner at 80kVp/500mA. Images were reconstructed at end diastole and end systole with both filtered back projection and using the "standard" adaptive iterative dose reduction (AIDR) algorithm. For each acquisition, 9 lower dose acquisitions were created. End systolic myocardial function maps were calculated using SQUEEZ for all noise levels and contrast-to-noise ratio (CNR) between the left ventricle blood and myocardium was calculated as a measure of image quality. For acquisitions with CNR > 4, SQUEEZ could be estimated with a precision of ± 0.04 (p < 0.001) or 5.7% of its dynamic range. The difference between SQUEEZ values calculated from AIDR and FBP images was not statistically significant. Regional wall motion abnormality can be quantified with good precision from low dose acquisitions, using SQUEEZ, as long as the blood-myocardium CNR stays above 4.

Relationship between left ventricular diastolic dyssynchrony and systolic dyssynchrony in hypertrophic cardiomyopathy by single-cardiac real-time three-dimensional ultrasonography.

The relationship between left ventricular diastolic and systolic dyssynchrony in hypertrophic cardiomyopathy (HCM) was investigated by single-cardiac real-time three-dimensional ultrasonography. A total of 52 patients with HCM were selected in Jining No. 1 People's Hospital from July 2016 to June 2017. Additionally, a total of 52 healthy people were selected to serve as the control group. All participants received real-time two- and three-dimensional ultrasonography to evaluate left ventricular morphology, function and systolic and diastolic function. The relevant parameters included left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), end-systolic/diastolic sphericity index (ESSI/EDSI), systolic dyssynchrony index (SDI), diastolic dyssynchrony index (DDI), dispersion end systole (DISPES), diastolic dyssynchrony index-late (DDI-late) and dispersion end diastole (DISPED-late). The LVEF of observation group was significantly lower than that of the control group, while LVEDV, LVESV, E/A and E/Ea were significantly higher than those in control group (P<0.05); EDSI, DDI-late and DISPED-late were significantly higher in observation than in control group (P<0.05); ESSI, SDI and DISPES in observation were significantly higher than those in control group (P<0.05); The 16-segment time-volume curve of observation group was disordered without synchronization, while the curve of control group was regular and smooth with synchronization; Pearson's correlation analysis showed that SDI and DDI were positively correlated (P<0.05). In conclusion, three-dimensional ultrasonography can be used to effectively evaluate left ventricular diastolic and systolic dyssynchrony in HCM. The severity of diastolic is positively correlated with systolic dyssynchrony.

Comparison of 2D versus M-mode echocardiography for assessing fetal myocardial wall thickness

Objective: M-mode and 2D have been proposed for evaluating fetal myocardial thickness. However, studies comparing the performance of both modalities are lacking. We aimed to compare 2D versus M-mode reproducibility for assessing myocardial wall thicknesses.Methods: A prospective study including 45 healthy fetuses from low-risk pregnancies evaluated between 18 and 41 weeks of gestation. Left and right ventricular free-wall and septal myocardial thicknesses were measured at end-diastole (ED) and end-systole (ES) in transverse 4-chamber view using 2D and M-mode. Intra- and interobserver reproducibility was evaluated by the concordance correlation coefficient (CCC). Both techniques were compared by t-test of the CCC.Results: 2D and M-mode demonstrated excellent and similar intraobserver repeatability, with the best concordance in ES septal thickness (M-mode CCC 0.956 versus 2D-mode CCC 0.914). Interobserver reproducibility demonstrated also a high concordance, optimal in ES left ventricular free wall (M-mode 0.925 versus 2 D 0.855). Comparison of both techniques demonstrated a high concordance in all measurements, except for ED septal thickness with better reproducibility using M-mode (CCC 0.954 versus 0.847, p = .017).Conclusions: 2D and M-mode can be used in a reproducible manner for measuring fetal myocardial thickness, with a slightly better performance of M-mode for assessing ED septal wall thickness.

Comparison of left ventricular strains and torsion derived from feature tracking and DENSE CMR

BackgroundCardiovascular magnetic resonance (CMR) feature tracking is increasingly used to quantify cardiac mechanics from cine CMR imaging, although validation against reference standard techniques has been limited. Furthermore, studies have suggested that commonly-derived metrics, such as peak global strain (reported in 63% of feature tracking studies), can be quantified using contours from just two frames – end-diastole (ED) and end-systole (ES) – without requiring tracking software. We hypothesized that mechanics derived from feature tracking would not agree with those derived from a reference standard (displacement-encoding with stimulated echoes (DENSE) imaging), and that peak strain from feature tracking would agree with that derived using simple processing of only ED and ES contours.MethodsWe retrospectively identified 88 participants with 186 pairs of DENSE and balanced steady state free precession (bSSFP) image slices acquired at the same locations across two institutions. Left ventricular (LV) strains, torsion, and dyssynchrony were quantified from both feature tracking (TomTec Imaging Systems, Circle Cardiovascular Imaging) and DENSE. Contour-based strains from bSSFP images were derived from ED and ES contours. Agreement was assessed with Bland-Altman analyses and coefficients of variation (CoV). All biases are reported in absolute percentage.ResultsComparison results were similar for both vendor packages (TomTec and Circle), and thus only TomTec Imaging System data are reported in the abstract for simplicity. Compared to DENSE, mid-ventricular circumferential strain (Ecc) from feature tracking had acceptable agreement (bias: − 0.4%, p = 0.36, CoV: 11%). However, feature tracking significantly overestimated the magnitude of Ecc at the base (bias: − 4.0% absolute, p < 0.001, CoV: 18%) and apex (bias: − 2.4% absolute, p = 0.01, CoV: 15%), underestimated torsion (bias: − 1.4 deg/cm, p < 0.001, CoV: 41%), and overestimated dyssynchrony (bias: 26 ms, p < 0.001, CoV: 76%). Longitudinal strain (Ell) had borderline-acceptable agreement (bias: − 0.2%, p = 0.77, CoV: 19%). Contour-based strains had excellent agreement with feature tracking (biases: − 1.3–0.2%, CoVs: 3–7%).ConclusionCompared to DENSE as a reference standard, feature tracking was inaccurate for quantification of apical and basal LV circumferential strains, longitudinal strain, torsion, and dyssynchrony. Feature tracking was only accurate for quantification of mid LV circumferential strain. Moreover, feature tracking is unnecessary for quantification of whole-slice strains (e.g. base, apex), since simplified processing of only ED and ES contours yields very similar results to those derived from feature tracking. Current feature tracking technology therefore has limited utility for quantification of cardiac mechanics.

Realization of fully automated quantification of left ventricular volumes and systolic function using transthoracic 3D echocardiography

BackgroundStudy on automated three-dimensional (3D) quantification of left heart parameters by using Heartmodel software is still in the early stage and fully automatic analysis was not clearly achieved. The aim of our study was to evaluate the performance of this new technology in measuring left ventricular (LV) volume and ejection fraction (EF) in patients with a variety of heart diseases on the basis of rationally determining the default endocardial border values.MethodsSubjects with a variety of heart diseases were included prospectively. High quality Heartmodel images were selected to determine the end-diastolic and end-systolic default values of endocardial border. The accuracy and reproducibility of automated three-dimensional echocardiography (3DE) for measuring LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF were evaluated with the traditional manual 3DE as the relative standard.ResultsNinety seven subjects were enrolled in the study. The default endocardial border values were determined as 66% and 40% for end-diastole (ED) and end-systole (ES), respectively. Most of the subjects (84/97) were automatically analyzed by Heartmodel software without manual adjustment, revealing a close correlation of automated 3DE with manual 3DE in measuring EDV, ESV and EF (r-values: EDV: 0.96, ESV: 0.97, EF: 0.96). The EDV and ESV values obtained by automated 3DE were higher than those measured by manual 3DE (biases: EDV: 16 ± 18 ml, ESV: 11 ± 12 ml). The intra- and inter-observer reproducibility of automated 3DE was better than that of manual 3DE. Automated 3DE with manual adjustment showed good consistency with manual 3DE in assessing the impairment degree of systolic function in patients with wall motion abnormalities (n = 58), (Kappa = 0.74, P = 0.00).ConclusionFully automated 3DE quantification of LV volume and EF could be achieved in most patients. Since automated 3DE was accurate and more reproducible, it could replace the existing manual 3DE technology and be routinely used in clinical practice.