Functional importance of the long axis dynamics of the human left ventricle

Multiaxial pressure-strain analysis of regional myocardial work in the setting of graded coronary stenoses and dobutamine stress

We present a detailed analysis of regional myocardial blood flow and work to better understand the effects of coronary stenoses and low-dose dobutamine stress. Our analysis is based on a unique open-chest model in anesthetized canines that features invasive hemodynamic monitoring, microsphere-based blood flow analysis, and an extensive three-dimensional (3-D) sonomicrometer array that provides multiaxial deformational assessments in the ischemic, border, and remote vascular territories. We use this model to construct regional pressure-strain loops for each territory and quantify the loop subcomponent areas that reflect myocardial work contributing to the ejection of blood and wasted work that does not. We demonstrate that reductions in coronary blood flow markedly alter the shapes and temporal relationships of pressure-strain loops, as well as the magnitudes of their total and subcomponent areas. Specifically, we show that moderate stenoses in the mid-left anterior descending coronary artery decrease regional midventricle myocardial work indices and substantially increase indices of wasted work. In the midventricle, these effects are most pronounced along the radial and longitudinal axes, with more modest effects along the circumferential axis. We further demonstrate that low-dose dobutamine can help to restore or even improve function, but often at the cost of increased wasted work. This detailed, multiaxial analysis provides unique insight into the physiology and mechanics of the heart in the presence of ischemia and low-dose dobutamine, with potential implications in many areas, including the detection and characterization of ischemic heart disease and the use of inotropic support for low cardiac output.NEW & NOTEWORTHY Our unique experimental model assesses cardiac pressure-strain relationships along multiple axes in multiple regions. We demonstrate that moderate coronary stenoses decrease regional myocardial work and increase wasted work and that low-dose dobutamine can help to restore myocardial function, but often with further increases in wasted work. Our findings highlight the significant directional variation of cardiac mechanics and demonstrate potential advantages of pressure-strain analyses over traditional, purely deformational measures, especially in characterizing physiological changes related to dobutamine.

Automated quantitative evaluation of fetal atrioventricular annular plane systolic excursion

OBJECTIVES

The primary aim of this study was to evaluate the feasibility of automated measurement of fetal atrioventricular (AV) plane displacement (AVPD) over several cardiac cycles using myocardial velocity traces obtained by color tissue Doppler imaging (cTDI). The secondary objectives were to establish reference ranges for AVPD during the second half of normal pregnancy, to assess fetal AVPD in prolonged pregnancy in relation to adverse perinatal outcome and to evaluate AVPD in fetuses with a suspicion of intrauterine growth restriction (IUGR).

METHODS

The population used to develop the reference ranges consisted of women with an uncomplicated singleton pregnancy at 18-42 weeks of gestation (n = 201). The prolonged-pregnancy group comprised women with an uncomplicated singleton pregnancy at ≥ 41 + 0 weeks of gestation (n = 107). The third study cohort comprised women with a singleton pregnancy and suspicion of IUGR, defined as an estimated fetal weight < 2.5^th centile or an estimated fetal weight < 10^th centile and umbilical artery pulsatility index > 97.5^th centile (n = 35). Cineloops of the four-chamber view of the fetal heart were recorded using cTDI. Regions of interest were placed at the AV plane in the left and right ventricular walls and the interventricular septum, and myocardial velocity traces were integrated and analyzed using an automated algorithm developed in-house to obtain mitral (MAPSE), tricuspid (TAPSE) and septal (SAPSE) annular plane systolic excursion. Gestational-age specific reference ranges were constructed and normalized for cardiac size. The correlation between AVPD measurements obtained using cTDI and those obtained by anatomic M-mode were evaluated, and agreement between these two methods was assessed using Bland-Altman analysis. The mean Z-scores of fetal AVPD in the cohort of prolonged pregnancies were compared between cases with normal and those with adverse outcome using Mann-Whitney U-test. The mean Z-scores of fetal AVPD in IUGR fetuses were compared with those in the normal reference population using Mann-Whitney U-test. Inter- and intraobserver variability for acquisition of cTDI recordings and offline analysis was assessed by calculating coefficients of variation (CV) using the root mean square method.

RESULTS

Fetal MAPSE, SAPSE and TAPSE increased with gestational age but did not change significantly when normalized for cardiac size. The fitted mean was highest for TAPSE throughout the second half of gestation, followed by SAPSE and MAPSE. There was a significant correlation between MAPSE (r = 0.64; P < 0.001), SAPSE (r = 0.72; P < 0.001) and TAPSE (r = 0.84; P < 0.001) measurements obtained by M-mode and those obtained by cTDI. The geometric means of ratios between AVPD measured by cTDI and by M-mode were 1.38 (95% limits of agreement (LoA), 0.84-2.25) for MAPSE, 1.00 (95% LoA, 0.72-1.40) for SAPSE and 1.20 (95% LoA, 0.92-1.57) for TAPSE. In the prolonged-pregnancy group, the mean ± SD Z-scores for MAPSE (0.14 ± 0.97), SAPSE (0.09 ± 1.02) and TAPSE (0.15 ± 0.90) did not show any significant difference compared to the reference ranges. Twenty-one of the 107 (19.6%) prolonged pregnancies had adverse perinatal outcome. The AVPD Z-scores were not significantly different between pregnancies with normal and those with adverse outcome in the prolonged-pregnancy cohort. The mean ± SD Z-scores for SAPSE (-0.62 ± 1.07; P = 0.006) and TAPSE (-0.60 ± 0.89; P = 0.002) were significantly lower in the IUGR group compared to those in the normal reference population, but the differences were not significant when the values were corrected for cardiac size. The interobserver CVs for the automated measurement of MAPSE, SAPSE and TAPSE were 28.1%, 17.7% and 15.3%, respectively, and the respective intraobserver CVs were 33.5%, 15.0% and 17.9%.

CONCLUSIONS

This study showed that fetal AVPD can be measured automatically by integrating cTDI velocities over several cardiac cycles. Automated analysis of AVPD could potentially help gather larger datasets to facilitate use of machine-learning models to study fetal cardiac function. The gestational-age associated increase in AVPD is most likely a result of increasing cardiac size, as the AVPD normalized for cardiac size did not change significantly between 18 and 42 weeks. A decrease was seen in TAPSE and SAPSE in IUGR fetuses, but not after correction for cardiac size. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Assessment of longitudinal systolic function using tissue motion annular displacement in dogs with degenerative mitral valve disease

INTRODUCTION

Although degenerative mitral valve disease (DMVD) is essentially a disorder of the valve, the progression of the disease leads to structural myocardial changes that may compromise left ventricular systolic function. Tissue motion annular displacement (TMAD) is a surrogate for longitudinal fiber function based on speckle tracking assessment of the movement of the mitral annulus toward the apex during systole. The aim of this study was to evaluate longitudinal systolic function with TMAD in dogs with DMVD.

ANIMALS

Ninety-four dogs with DMVD and 32 healthy dogs.

METHODS

Prospective cross-sectional observational study. Dogs with DMVD of various American College of Veterinary Internal Medicine classification stages and healthy control dogs underwent physical examination, electrocardiography, systolic blood pressure measurement, as well as a standard and speckle tracking echocardiography. Global longitudinal strain (GLS) and TMAD were used to assess longitudinal systolic function.

RESULTS

The global TMAD_mm and global TMAD_% were higher in American College of Veterinary Internal Medicine B2 animals than in the stage CD. Global TMAD _(mm/kg,_mm/bodyweight3, _mm/m²) were correlated with GLS and ejection fraction. Global TMAD _(mm/kg,_mm/m²,%) and GLS were influenced by sex. In addition, systolic blood pressure influenced GLS (P < 0.01; r = -0.23), global TMAD_mm/kg (P = 0.017; r = -0.21) and global TMAD_mm/m² (P = 0.031; r = -0.19). Tissue motion annular displacement was fast to be performed and produced good repeatability in dogs with DMVD.

CONCLUSIONS

Global TMAD _(mm,%), was reduced in DMVD dogs with clinical signs of heart failure compared with stage B2. Tissue motion annular displacement was shown to be a repeatable technique for evaluation of longitudinal systolic function in dogs with DMVD.

Prediction of Significant Coronary Artery Disease Through Advanced Echocardiography: Role of Non-invasive Myocardial Work

Background: Non-invasive prediction of critical coronary artery stenosis (CAST) in patients with coronary artery disease (CAD) is challenging. Strain parameters can often capture an impairment of regional longitudinal function; however, they are load dependent. A novel non-invasive method to estimate Myocardial Work (MW) has been recently proposed, showing a strong correlation with invasive work measurements. Our aim was to investigate the ability of non-invasive MW to predict the ischaemic risk area underlying a CAST. Methods and Results: The study population comprises 80 individuals: 50 patients with CAST and 30 controls (CTRL). Echocardiography recordings were obtained before coronary angiography to measure global longitudinal strain (GLS), Myocardial Work Index (MWI), Myocardial Constructive Work (MCW), Myocardial Wasted work (MWW), Myocardial Work Efficiency (MWE). Global MWI (p = 0.048), MWE (p < 0.001), and MCW (p = 0.048) at baseline were significantly reduced in patients with CAST compared to controls (p < 0.05). Regional MWE within the myocardial segments underlying the CAST, but not LS, was significantly reduced compared to non-target segments (p < 0.001). At ROC analysis, the diagnostic performance to predict CAST for regional MWE (AUC = 0.920, p < 0.001) was higher compared to both regional post-systolic shortening index (PSI) (AUC = 0.600, p = 0.129) and regional LS (AUC = 0.546, p = 0.469). Conclusions: Non-invasive estimation of MW work indices is able to predict a CAST before invasive angiography.

Feasibility and Reliability of Automatic Quantitative Analyses of Mitral Annular Plane Systolic Excursion by Handheld Ultrasound Devices: A Pilot Study

OBJECTIVES

Handheld ultrasound devices (HUDs) have previously been limited to grayscale imaging without options for left ventricle (LV) quantification. We aimed to study the feasibility and reliability of automatic measurements of mitral annular plane systolic excursion (MAPSE) by HUDs.

METHODS

An algorithm that automatically measured MAPSE from live grayscale recordings was implemented in a HUD. Twenty patients at a university hospital were examined by either a cardiologist or a sonographer. Standard echocardiography using a high-end scanner was performed. The apical 4-chamber view was recorded 4 times by both echocardiography and the HUD. MAPSE was measured by M-mode and color tissue Doppler (cTD) during echocardiography and automatically by the HUD.

RESULTS

The automatic method underestimated mean MAPSE ± SD versus M-mode (9.6 ± 2.2 versus 10.9 ± 2.6 mm; difference, 1.2 ± 1.4 mm, P < .005). The difference between the automatic and cTD measurements was not significant (0.8 ± 1.8 mm; P = .073). The intraclass correlation coefficients (ICCs) between automatic and M-mode measurements was 0.85, and 0.81 for cTD measurements. There was good agreement between the methods, and the intra- and inter-rater ICCs were excellent for all methods (≥0.86).

CONCLUSIONS

In this novel study evaluating automatic quantification of LV longitudinal function by HUD, we showed the high feasibility and reliability of the method. Compared to M-mode imaging, the automatic method underestimated MAPSE by 8% to 10%, but the difference with cTD imaging was nonsignificant. We conclude that this study's method for automatic quantitative assessment of LV function can be integrated in HUDs.

Non-invasive myocardial work is reduced during transient acute coronary occlusion

Background

During ischemia a close relationship exists between sub-endocardial blood flow and myocardial function. Strain parameters can capture an impairment of regional longitudinal function but are load dependent. Recently, a novel non-invasive method to calculate Myocardial Work (MW) showed a strong correlation with invasive work measurements.

Our aim was to investigate the ability of non-invasive MW indices to identify the ischaemic risk area during transient acute coronary occlusion (TACO).

Methods and results

The study population comprises 50 individuals with critical coronary stenosis (CCS). Echocardiography recordings were obtained before coronary angiography, during TACO and after revascularization to measure global longitudinal strain (GLS), Myocardial Work Index (MWI), Myocardial Constructive Work (MCW), Myocardial Wasted work (MWW), Myocardial work efficiency (MWE).

Compared to baseline, we found a significant reduction of GLS (p = 0.005), MWI, MCW and MWE (p<0.001) during TACO.

Conclusions

The non-invasive measurement of MW parameters is a sensitive and early marker of myocardial ischemia during TACO.

Echocardiographic assessment of left ventricular size and systolic function in Warmblood horses using linear measurements, area-based indices, and volume estimates: A retrospective database analysis

Background

Echocardiographic assessment of left ventricular (LV) size and function using area‐based indices and volumetric estimates is not well established in horses.

Objective

To report reference intervals and measurement variability for uni‐, 2‐, and 3‐dimensional echocardiographic indices of LV size and systolic function in Warmblood horses and to provide proof of concept for allometric scaling of variables to body weight. Unidimensional indices were to be compared to area‐based indices and LV volume estimates to establish their clinical use.

Animals

Thirty healthy Warmblood horses and 70 Warmblood horses with a primary diagnosis of mitral regurgitation or aortic regurgitation.

Methods

Echocardiographic indices of LV size and systolic function were measured using an existing echocardiography database. Weight‐related variables were scaled to body weight (BWT). Reference intervals and measurement variability were calculated, the influence of valvular regurgitation on LV size and function was investigated and agreement between different variables for detection of reduced, normal, and increased LV size and systolic function was assessed.

Results

Reference values for healthy Warmblood horses were reported. Measurement variability was sufficiently low for clinical use of all variables. Allometric scaling was effective to correct diastolic LV dimensions and cardiac output for differences in BWT. Various echocardiographic indices resulted in different conclusions regarding identification of LV enlargement and systolic dysfunction in healthy horses and horses with valvular regurgitation.

Conclusions and Clinical Importance

Echocardiographic assessment of LV size and systolic function should include joint assessment of multiple uni‐ and multidimensional indices. Area‐based or volumetric indices that reflect LV long‐axis motion should be included.

Severe Aortic Valve Stenosis: Symptoms, Biochemical Markers, and Global Longitudinal Strain

BACKGROUND

According to the actual guidelines regarding severe aortic valve stenosis (AS), symptoms are the most important trigger for aortic valve replacement (AVR). However, the objective analysis of cardiological clinic can be confused, considering the aging population this disease affects and the comorbidities.

OBJECTIVES

Looking for an objective marker of disease, useful for scheduling the correct AVR, we researched the relation between some biochemical markers of left ventricular (LV) dysfunction and its global longitudinal strain.

MATERIALS AND METHODS

We analyzed 74 consecutive patients (82 ± 4 years) with severe AS. We identified 61 patients with symptoms (angina, dyspnea, and syncope) and 13 asymptomatic patients. The clinical and echocardiographic parameters were compared between these two groups. LV ejection fraction (LVEF), LV global longitudinal strain (LVGLS), NT-pro-B-type brain natriuretic peptide (BNP), troponin T (TNT), creatine kinase-MB (CPK-MB), and myoglobin were determined at the time of evaluation.

RESULTS

Compared with the asymptomatic group, patients in the symptomatic group had a lower LVGLS (P = 0.002) and an increased pro-BNP (P = 0.0002). LVGLS showed a good correlation with pro-BNP as a marker of myocardial damage, with a linear increase of pro-BNP in patients with a linear decrease of LVGLS (r = 0.43). Despite the normal value of LVEF > 50% in asymptomatic patients, some of them (46%) have an early dysfunction of LVGLS. No other statistically significant difference emerged from the biochemical analysis, in TNT (P = 0.29), CPK-MB (P = 0.36), and myoglobin (P = 0.38).

CONCLUSIONS

Pro-BNP and LVGLS can be considered an objective marker of clinical severity of AS disease, useful for management and scheduling of AVR, especially in asymptomatic patients.

Assessment of fetal cardiac function with echocardiography

The circulatory physiology of fetuses differs from that of neonates. The concept of biventricular combined cardiac output is necessary to understand and assess the fetal cardiac function. Fetal cardiac function has been estimated using echocardiographic methods such as M-mode, B-mode and pulsed wave Doppler. In addition, recent studies have reported the utility of tissue Doppler imaging in fetal echocardiography. However, parameters for fetal cardiac function remain to be established. Recently, we developed two novel techniques for assessing fetal cardiac function: an automatic fractional shortening method and E/e' determination using the dual-gate Doppler method. These two techniques are expected to be reliable and useful for assessing the fetal status in various pathological conditions.

Reduced regional strain rate is the most accurate dysfunction in predicting culprit lesions in patients with acute coronary syndrome

BACKGROUND AND AIM

Predicting culprit lesions in acute coronary syndrome (ACS) could be a challenge. The aim of this study was to assess the accuracy of regional wall motion abnormalities (RWMA) using various echocardiographic techniques and ECG changes in predicting the culprit coronary lesion in a group of patients with ACS.

METHODS

In 80 consecutive patients with ACS (age 55·7 ± 9·4 years, 77% male, 15% with CCS Angina III), an echocardiographic examination of left ventricle (LV) RWMA, tissue Doppler imaging (TDI) and speckle tracking myocardial strain and strain rate (SR) were performed before intervention.

RESULTS

Of the 80 patients, one-vessel stenosis (>70%) was present in 53 (66%), two-vessel disease in 12 (15%) and multivessel disease in 15 patients (19%). About 51% of patients had hypertension, 40% diabetes and 23% dyslipidaemia. There was no relationship between individual segmental RWMA and SR. Mean regional SR, but not peak strain, correlated with culprit lesion branch: left anterior descending - LAD (r = 0·35, P = 0·005), circumflex LCx (r = 0·32, P = 0·03) and right coronary RCA (r = 0·37, P = 0·01). Only ECG changes in the LAD territory (r = 0·26, P = 0·04) correlated with the culprit lesion. SR of LAD territories ≤-0·74 was 71% sensitive and 70% specific (AUC = 0·70, CI = 0·67-0·93, P = 0·01), SR of LCx territories of ≤-0·67 was 75% sensitive and 63% specific (AUC = 0·72, CI = 0·58-0·87, P = 0·02) and SR of RCA territories ≤-0·83 was 73% sensitive and 71% specific (AUC = 0·80, CI = 0·66-0·93, P = 0·001) in predicting significant stenosis. SR was more accurate than all other techniques in predicting the culprit lesion.

CONCLUSION

In ACS, mean regional speckle tracking SR is more sensitive than peak strain, TDI, ECG changes and wall motion abnormalities in detecting significant coronary artery stenosis.

Feasibility of automated fetal fractional shortening measurement with two-dimensional tracking and construction of a reference range for normal fetuses

PURPOSE

To assess the feasibility of an automated fractional shortening (Auto FS) measurement method using two-dimensional tracking and to construct a reference range for normal fetuses.

METHODS

This study was conducted from May 2017 to March 2018. First, cardiac motion in the four-chamber view was recorded in the B-mode. Subsequently, the region of interest was set on the edge of the ventricular septum or ventricular muscle at a point one-third away from the atrioventricular valve toward the cardiac apex. Tracking was automatically performed. Values measured between the ventricular septum and right ventricle were defined as R-Auto FS, whereas those measured between the ventricular septum and left ventricle were defined as L-Auto FS. Those on each ventricular muscle were defined as Combined-Auto FS.

RESULTS

Data were obtained from 131 singleton fetuses. R-Auto FS significantly decreased with an increase in the number of gestational weeks, and L-Auto FS and Combined-Auto FS showed the same tendency (Spearman's correlation analysis: p = - .528, p = - .351, and p = - .636, respectively).

CONCLUSION

We succeeded in defining a reference Auto FS value for normal singleton pregnancies. Auto FS was negatively correlated with gestational age. This novel technique can assess fetal heart contractility.

Aging and the relationships between long-axis systolic and early diastolic excursion, isovolumic relaxation time and left ventricular length-Implications for the interpretation of aging effects on e`

BACKGROUND

Both the left ventricular (LV) long-axis peak early diastolic lengthening velocity (e`) and long-axis early diastolic excursion (EDExc) decrease with age, but the mechanisms underlying these decreases are not fully understood. The aim of this study was to investigate the relative contributions to aging-related decreases in e`and EDExc from LV long-axis systolic excursion (SExc), isovolumic relaxation time (IVRT, as a measure of the speed of relaxation) and LV end-diastolic length (LVEDL).

METHODS

The study group was 50 healthy adult subjects of ages 17-75 years with a normal LV ejection fraction. SExc, EDExc, e`and IVRT were measured from pulsed wave tissue Doppler signals acquired from the septal and lateral walls. Multivariate modelling was performed to identify independent predictors of EDExc and e`which were consistent for the septal and lateral walls.

RESULTS

EDExc decreased with age and the major determinant of EDExc was SExc, which also decreased with age. There was also a decrease of e`with age, and the major determinant of e`was EDExc. IVRT decreased with age and on univariate analysis was not only inversely correlated with EDExc and e`, but also with SExc. IVRT was only a minor contributor to models of EDExc which included SExc, and was an inconsistent contributor to models of e`which included EDExc. LVEDL decreased with age independent of sex and body size, and was positively correlated with SExc, EDExc and e`.

CONCLUSION

Major mechanisms underlying the decrease in e`seen during aging are the concomitant decreases in long-axis contraction and early diastolic excursion, which are in turn related in part to long-axis remodelling of the left ventricle. After adjusting for the extent of systolic and early diastolic excursion, slowing of relaxation, as reflected in prolongation of the IVRT, makes no more than a minor contribution to aging-related decreases in EDExc and e`.

Are Measures of Left Ventricular Longitudinal Shortening Affected by Left Atrial Enlargement?

BACKGROUND

Even though left atrial (LA) size and function are intimately related to left ventricular (LV) diastolic dysfunction, the role of LA with regard to LV systolic function is less clear. Consequently, we examined the potential association that might exist between measures of longitudinal LV systolic shortening and LA dilation using LA volume index (LAVI).

METHODS

In this retrospective analysis, data from 75 echocardiograms (mean age 53 ± 14; range 24 - 89 years; mean body surface area (BSA) 2.0 ± 0.3) were analyzed.

RESULTS

Peak global longitudinal (PGLS) correlated best with LV mass index (LVMI) followed by mitral annular systolic excursion (MAPSE), and age. Similar results were obtained when analyzing the best variables that correlated with LAVI. Finally, MAPSE correlated best with PGLS, then with MA tissue Doppler systolic velocity, BSA, and LAVI in that order. All patients had normal LV ejection fraction (LVEF) and normal sinus rhythm when studied.

CONCLUSIONS

LAVI does not directly affect LV systolic function and longitudinal measures of LV shortening are mainly dependent on LV mass. Additional studies are now required to determine how these associations vary when different degrees of LV dilatation and systolic dysfunction are included in the analysis.

Left ventricular endocardial and epicardial strain changes with apical myocardial ischemia in an open-chest porcine model

Early detection of acute myocardial ischemia is critical to prevent permanent myocardial damage. The impact of apical ischemia on global left ventricular (LV) function can be difficult to characterize using traditional volume‐based echocardiography measures. Myocardial strain imaging is a sensitive, quantitative marker of myocardial deformation that can measure ventricular function. Recent advances allow layer‐specific measurement of endo‐ and epicardial strain, enhancing the ability to evaluate myocardial ischemia. This study investigates the effects of apical ischemia on LV function using epi‐ and endocardial strain. We hypothesize that myocardial strain will identify changes in regional and global myocardial function associated with focal apical ischemia as compared to ejection fraction (EF), and that longitudinal strain will be a better indicator of myocardial dysfunction compared to circumferential or radial strain. In a porcine model (n = 9), acute ischemia was induced by left anterior descending coronary artery occlusion. Echocardiograms were performed at baseline, during 15‐min ischemia, and after reperfusion. Global longitudinal strain decreased with acute focal ischemia of the left ventricular apical region (baseline: −16.4% vs. ischemia: −12.2%; P = 0.010), with no change observed in global circumferential and radial strain or EF. Both endocardial and epicardial longitudinal strain decreased by 68% (P < 0.001) in the ischemic and peri‐ischemic zone, while circumferential and radial strain only decreased in endocardium of the ischemic zone. Longitudinal strain was more sensitive to ischemia, being able to detect changes in global LV function and thus may confer clinical diagnostic advantage in the evaluation of acute LV apical ischemia.

Long Term Osmotic Mini Pump Treatment with Alpha-MSH Improves Myocardial Function in Zucker Diabetic Fatty Rats

The present investigation evaluates the cardiovascular effects of the anorexigenic mediator alpha-melanocyte stimulating hormone (MSH), in a rat model of type 2 diabetes. Osmotic mini pumps delivering MSH or vehicle, for 6 weeks, were surgically implanted in Zucker Diabetic Fatty (ZDF) rats. Serum parameters, blood pressure, and weight gain were monitored along with oral glucose tolerance (OGTT). Echocardiography was conducted and, following sacrifice, the effects of treatment on ischemia/reperfusion cardiac injury were assessed using the isolated working heart method. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was measured to evaluate levels of oxidative stress, and force measurements were performed on isolated cardiomyocytes to determine calcium sensitivity, active tension and myofilament co-operation. Vascular status was also evaluated on isolated arterioles using a contractile force measurement setup. The echocardiographic parameters ejection fraction (EF), fractional shortening (FS), isovolumetric relaxation time (IVRT), mitral annular plane systolic excursion (MAPSE), and Tei-index were significantly better in the MSH-treated group compared to ZDF controls. Isolated working heart aortic and coronary flow was increased in treated rats, and higher Hill coefficient indicated better myofilament co-operation in the MSH-treated group. We conclude that MSH improves global heart functions in ZDF rats, but these effects are not related to the vascular status.

Expert consensus document: Echocardiography and lung ultrasonography for the assessment and management of acute heart failure

Echocardiography is increasingly recommended for the diagnosis and assessment of patients with severe cardiac disease, including acute heart failure. Although previously considered to be within the realm of cardiologists, the development of ultrasonography technology has led to the adoption of echocardiography by acute care clinicians across a range of specialties. Data from echocardiography and lung ultrasonography can be used to improve diagnostic accuracy, guide and monitor the response to interventions, and communicate important prognostic information in patients with acute heart failure. However, without the appropriate skills and a good understanding of ultrasonography, its wider application to the most acutely unwell patients can have substantial pitfalls. This Consensus Statement, prepared by the Acute Heart Failure Study Group of the ESC Acute Cardiovascular Care Association, reviews the existing and potential roles of echocardiography and lung ultrasonography in the assessment and management of patients with acute heart failure, highlighting the differences from established practice where relevant.

End-systolic Pressure-Volume Relation, Ejection Fraction, and Heart Failure: Theoretical Aspect and Clinical Applications

A mathematical formalism describing the nonlinear end-systolic pressure–volume relation (ESPVR) is used to derive new indexes that can be used to assess the performance of the heart left ventricle by using the areas under the ESPVR (units of energy), the ordinates of the ESPVR (units of pressure), or from slopes of the curvilinear ESPVR. New relations between the ejection fraction (EF) and the parameters describing the ESPVR give some insight into the problem of heart failure (HF) with normal or preserved ejection fraction. Relations between percentage occurrence of HF and indexes derived from the ESPVR are also discussed. When ratios of pressures are used, calculation can be done in a noninvasive way with the possibility of interesting applications in routine clinical work. Applications to five groups of clinical data are given and discussed (normal group, aortic stenosis, aortic valvular regurgitation, mitral valvular regurgitation, miscellaneous cardiomyopathies). No one index allows a perfect segregation between all clinical groups, it is shown that appropriate use of two indexes (bivariate analysis) can lead to better separation of different clinical groups.

Early detection of regional and global left ventricular myocardial function using strain and strain-rate imaging in patients with metabolic syndrome

BACKGROUND

Strain and strain-rate imaging (SRI) have been found clinically useful in the assessment of cardiac systolic and diastolic function as well as providing new insights in deciphering cardiac physiology and mechanics in cardiomyopathies, and identifying early subclinical changes in various pathologies. The aim of this study was to evaluate the regional and global left ventricular (LV) myocardial function in metabolic syndrome (MS) with SRI so that we can provide more myocardial small lesions in patients with MS, which is robust and reliable basis for early detection of LV function.

METHODS

Thirty-nine adults with MS were enrolled in the study. There was a control group of 39 healthy adults. In addition to classic echocardiographic assessment of LV global functional changes, SRI was used to evaluate regional and global LV function. Including: Peak systolic strain (S), peak systolic strain-rate (SR-s), peak diastolic strain-rate (SR-e).

RESULTS

There were no statistically significant differences between MS and controls in all traditional parameters of LV systolic function. On the other hand, significant differences were observed between MS and the control group in most of the parameters of S, SR-s, SR-e in regional LV function. Multiple stepwise regression analyses revealed that S and SR significantly were negatively correlated with blood pressure, waist circumference, fasting plasma glucose, uric acid, suggesting that risk factories were relevant to regional systolic dysfunction.

CONCLUSION

In MS with normal LV ejection fraction, there was regional myocardial dysfunction, risk factors contributed to the impairment of systolic and diastolic function of the regional myocardium. Assessment of myocardial function using SRI could be more accurate in MS patient evaluation than conventional echocardiography alone.

Echocardiographic changes in patients with stage 3-5 chronic kidney disease and left ventricular diastolic dysfunction

BACKGROUND

Left ventricular (LV) diastolic dysfunction in chronic kidney disease (CKD) patients frequently leads to the development of congestive heart failure. We evaluated changes in echocardiographic parameters among CKD patients with LV diastolic dysfunction.

METHODS

We examined 70 ambulatory patients with CKD at stages 3-5 and 26 patients without CKD as a control group. Standard echocardiography and tissue Doppler imaging were performed on all patients. Patients with CKD were divided into two groups according to the results of lateral mitral early diastolic velocity (EmLVlat): a group with diastolic dysfunction (DD group; EmLVlat <8 cm/s) and a group without diastolic dysfunction (WDD group; EmLVlat ≥8 cm/s).

RESULTS

Compared to the patients in the WDD group, those in the DD group were characterized by lower values of mitral annular plane systolic excursion [MAPSE; 13 (11-17) vs. 14 (11-16) mm, p < 0.0001] and lateral mitral annular systolic velocity [SmLVlat; 7 (5-14) vs. 8 (5-13) cm/s, p = 0.006]. The area under the receiver operating characteristic (ROC) curve of the MAPSE level for the detection of LV diastolic dysfunction was 0.801 [95% CI 0.684-0.890, p < 0.0001], whereas a ROC-derived MAPSE value of ≤13 mm was characterized by a sensitivity of 84.4% and a specificity of 75.8% for diagnosing LV diastolic dysfunction. The only independent variable predicting LV diastolic dysfunction was MAPSE [OR = 0.39; 95% CI 0.21-0.74, p = 0.003].

CONCLUSION

We showed that reduced MAPSE, but not SmLVlat, is an independent predictive factor for LV diastolic dysfunction in CKD patients.

Mitral annulus displacement measured by two-dimensional speckle tracking imaging to assess the left ventricular longitudinal systolic function in coronary heart disease

AIM

To assess the clinical utility of measuring mitral annulus displacement (MAD) by two-dimensional speckle tracking for the rapid evaluation of left ventricular longitudinal systolic function in patients with coronary heart disease (CHD).

METHODS

Left ventricular longitudinal systolic function was evaluated by MAD using speckle tracking echocardiography in 30 healthy volunteers (controls) as well as in 30 patients with mild, 30 patients with moderate, and 30 patients with severe CHD. All participants had their apical four-chamber and two-chamber view echocardiographic images recorded. Left ventricular end-diastolic volume, left ventricular end-systolic volume, and left ventricular ejection fraction were calculated by the biplane Simpson method. MAD of interventricular septum (MADsep), left ventricular lateral wall (MADlat), and the middle point of the mitral annulus (MADmid) were measured offline with speckle-tracking echocardiography. MADmid% was defined as MADmid divided by left ventricular end-diastolic diameter.

RESULTS

MADmid% was 16.9 ± 1.9, 11.8 ± 3.2, 11.8 ± 2.9, and 10.3 ± 3.6, respectively, in controls and in patients with mild, moderate, and severe CHD. All MAD indexes were lower in patients with moderate or severe CHD than in controls or patients with mild CHD.

CONCLUSIONS

MAD is an early and rapid index for the assessment of left ventricular longitudinal systolic function in patients with different degrees of coronary artery disease.

Different implication of elevated B-type natriuretic peptide level in patients with heart failure with preserved ejection fraction and in those with reduced ejection fraction

BACKGROUND

There have been no reports that show significant direct relationship between echocardiographic parameters and B-type natriuretic peptide (BNP) level. This could be due to the heterogeneous pathophysiology of heart failure and a lack of appropriate echocardiographic parameters. We sought to determine the best echocardiographic parameter that described elevated BNP level in patients with heart failure with and without systolic dysfunction.

METHODS AND RESULTS

We studied 111 consecutive heart failure patients. They were divided into patients with heart failure and preserved ejection fraction (HFPEF, n = 61) and that with heart failure and reduced ejection fraction (HFREF, n = 50). Conventional and new echocardiographic parameters including myocardial strains were measured. BNP did not reflect any single echocardiographic parameter in patients with heart failure in total. The ratio of early diastolic transmitral flow velocity and mitral annular velocity had strong positive correlation with BNP level in the HFPEF group but not in the HFREF group. In the group of HFREF, global longitudinal and circumferential strains were positively correlated. Multivariate analysis revealed that predicted factors for BNP value in HFPEF and in HFREF were different.

CONCLUSION

High BNP level may indicate high filling pressure when ejection fraction is preserved and may indicate myocardial dysfunction when it is reduced.

A study to determine the contribution to right ventricle stroke volume from pulmonary and tricuspid valve displacement volumes

BACKGROUND

Describing the systolic function of the right ventricle (RV) is a difficult task due to the complex shape and orientation of the RV. The purpose of this study was to investigate the extent to which the volumes encompassed by the pulmonary and tricuspid valve displacements contribute to the total right ventricle stroke volume (RVSV).

METHODS

Twelve healthy volunteers were examined using cardiac magnetic resonance (CMR). Two series of time-resolved axially rotated MR images were acquired that encompassed the tricuspid valve and the pulmonary valve, respectively. The volume related to each valve movement, the tricuspid plane displacement (TPD) and the pulmonary plane displacement (PPD), was determined by delineation in diastole and systole. These volumes, RVSV(TPD) and RVSV(PPD) , were compared to the stroke volume to determine the contributions to the total stroke volume from the TPD and the PPD. The remaining volume of the total RVSV was referred to as RVSV(Other) . An initial in vitro study was carried out to validate the accuracy of volume measurements using axially rotated images.

RESULTS

In vitro measurements indicated that the method for volumetric measurements using axially rotated images was a very accurate one, with a mean difference of 0·04 ± 0·10 ml. The in vivo measurements of RVSV(TPD) , RVSV(PPD) and RVSVOther were 45 ± 10%, 13 ± 2% and 42 ± 11%, respectively.

CONCLUSIONS

Right ventricle stroke volume is determined by different individual volume changes as follows: RVSV(TPD) together with RVSVOther contributes to almost the entire RVSV in nearly equal proportions, while RVSV(PPD) contributes only a small amount and is approximately 30% of either RVSV(TPD) or RVSV(Other) .

The relationship between mitral annular systolic velocity and ejection fraction in patients with preserved global systolic function of the left ventricle

BACKGROUND

The aim of the study was to investigate the relationship between the ejection fraction (EF) and the mitral annular systolic velocity (Sm) in patients with preserved left ventricular systolic function (EF>55%). The study task was to evaluate whether the assessment of Sm(avg) can be used as an alternative to the Simpson's method in assessment of the EF. The expected benefit was that Sm could be used to predict EF, when EF is difficult to assess due to poor image quality (IQ).

METHOD

Sm was obtained by spectral pulse wave Tissue Doppler Imaging (pwTDI) from the lateral and septal sites of the mitral annulus (MA) and an averaged value was calculated - Sm(avg). EF was assessed using Simpson's rule. Participants were divided into controls (n=70), hypertensive (HTN, n=56), HTN with diastolic dysfunction (HTN/DD, n=65), HTN with diabetes mellitus (HTN/DM, n=52) and HTN with DD and DM (HTN/DD/DM, n=65).

RESULTS

Sm(avg) showed strong correlation with EF (r=0.978; p<0.0001). There were no significant differences between the correlation coefficients between the subgroups and the controls. The mathematical model that the study recommended to assess the EF is: EF=45.0 + 2 × Sm(avg).

CONCLUSION

The assessment of Sm(avg) could be used as an alternative to EF. This approach may be useful especially when the IQ is poor. The method maintains high accuracy and reproducibility in prediction of the EF.

Right ventricular wall-motion changes after infant open heart surgery--a tissue Doppler study

BACKGROUND

Right ventricular (RV) dysfunction is a well-recognized complication of cardiopulmonary bypass surgery (CPB) in adults. Infants and neonates may also be at high risk for this due to immature myocardium. Conventional assessment of RV function is just qualitative, but novel tissue Doppler echocardiographic (TDI) markers including peak systolic strain rate (SR) and isovolumic contraction acceleration (IVA) permit noninvasive quantitation of RV function. This study assessed myocardial velocities, IVA and SR in infants and neonates undergoing open heart surgery using TDI to study regional myocardial function perioperatively.

METHODS

Transthoracic TDI data were obtained in the OR before and 24 hours post-CPB on 53 consecutive infants (age 0.39 ± 0.23 years). They were followed with TDI through hospital discharge.

RESULTS

Mean CPB time was 87 ± 49 min (cross-clamp 52 ± 26 min). Peak systolic (STDI ) and diastolic myocardial velocities (ETDI , ATDI ), IVA, and peak SR were recorded in RV and LV from standard views for offline analysis. Postoperatively, LV systolic function and diastolic longitudinal function were unchanged or improved from baseline. LV radial velocities were increased postoperatively indicating adequate support. In contrast, RV longitudinal systolic and diastolic function was significantly diminished after CPB. RV changes persisted through hospital discharge.

CONCLUSIONS

In infants and neonates, perioperative measurements of systolic and diastolic tissue Doppler parameters are feasible and revealed significant RV systolic and diastolic dysfunction post-CPB with preserved LV function. As such, TDI provides a sensitive tool to monitor the infant heart after CPB and may potentially be useful to assess different myocardial protection strategies.

Left Ventricular Diastolic Dysfunction — Early Cardiac Impairment in Patients with Polymyositis/Dermatomyositis: A Tissue Doppler Imaging Study

Objective.

To investigate early cardiac involvement in patients with polymyositis/dermatomyositis (PM/DM), and to evaluate the risk factors for early cardiac impairment.

Methods.

The study population included 46 patients with PM/DM who did not have overt cardiovascular manifestations and 21 age- and sex-matched healthy controls. Traditional echocardiography and tissue Doppler imaging (TDI) were used to evaluate cardiac function in both groups. Clinical characteristics were recorded. Multivariate logistics regression analysis was applied to investigate risk factors for early cardiac impairment in patients with PM/DM.

Results.

No significant difference was found between patients and controls by traditional echocardiography. However, compared to controls, PM/DM patients had a significantly lower ratio of early diastolic mitral annulus velocity to late diastolic mitral annulus velocity (Em/Am; 1.23 ± 0.52, 1.79 ± 0.37, respectively; t = −4.485, p < 0.001) and a higher ratio of peak early diastolic transmitral flow velocity to Em (E/Em; 8.26 ± 2.57, 6.76 ± 1.17; t = 3.287, p < 0.05) as found by TDI measurements. There was no significant difference between the TDI variables of patients with PM and DM. The multivariate regression analysis showed that female sex (OR 11.044, 95% CI 1.066–114.357, p = 0.044), late onset (OR 1.157, 95% CI 1.047–1.278, p = 0.004), and duration of disease (OR 1.060, 95% CI 1.008–1.115, p = 0.023) were risk factors for abnormal left ventricular filling pressures.

Conclusion.

TDI is useful for detecting early cardiac impairment in patients with PM/DM. Left ventricular diastolic dysfunction is an early feature of cardiac involvement. Female sex, late onset, and long course of disease are 3 independent risk factors for predicting left ventricular diastolic dysfunction in patients with PM/DM.

Speckle tracking echocardiography-determined measures of global and regional left ventricular function correlate with functional capacity in patients with and without preserved ejection fraction

Background

Standard measures of left ventricular systolic and diastolic function often fail to identify left ventricular dysfunction in patients with heart failure and do not correlate with measures of functional capacity.

Aim

To determine if speckle tracking echocardiography (STE)–determined measures of global and regional myocardial contractility have a linear association with functional capacity in patients with and without preserved ejection fraction.

Methods

In 68 adult patients, functional status was estimated with the Duke Activity Status Index (DASI), left ventricular ejection fraction was determined with Simpson’s biplane method, and QLAB advanced quantification software (Philips, The Netherlands) was used to determine peak measures of strain.

Results

Global and regional measures of longitudinal, circumferential, and radial strain had a strong linear association with the DASI score. Longitudinal strain in the inferolateral segments had the strongest correlation with DASI (r = −0.72, P < 0.001). In patients with an ejection fraction ≥45%, ejection fraction and E/e’ had no correlation with DASI, whereas longitudinal strain in the inferolateral segments had significant correlation with DASI (r = −0.53, P = 0.03, n = 16).

Conclusions

STE–determined measures of global and regional left ventricular function have a strong linear association with estimates of functional capacity in patients with and without preserved ejection fraction. STE–determined measures of strain, especially longitudinal strain, are likely to be important targets for therapy and should be considered in future studies aimed at improving our diagnosis of left ventricular inadequacy in patients with heart failure, especially those with preserved ejection fraction.

Left Ventricular Diastolic Function Assessment Using the Timing of Mitral Annular and Transmitral Flow Velocities

Background and aims:

Evaluation of left ventricular (LV) diastolic function plays an important role in clinical echocardiography. The relationship between mitral annular velocities from tissue Doppler imaging (TDI) (E′ and A′) and mitral inflow velocities (E and A) from Doppler echocardiography (DE) provide additional information about LV filling and diastolic function. The aims of this study are to i) assess the time differences between peak E and peak E′, peak A and peak A′, peak Ar and peak A, and ii) examine the effects of age and gender on these time intervals parameters in normal subjects.

Methods:

A total of 117 healthy subjects (age ranging from 22- to 78-years-old) were recruited for a standard of echocardiogram (ECHO). During early diastole, the time intervals from the peak of R-wave on the ECG to the peak of E-wave (R-pE), to the peak of E wave to peak of E′-wave (R-pE′) were measured. During late diastole, the time intervals from the onset of P-wave on the ECG to the peak A-wave (P-pA), to the peak Ar-wave on the pulmonary valve flow (P-pAr), to the peak A′-wave (P-pA′) were measured. Early-diastolic temporal discordance (EDTD) and late-diastolic temporal discordance (LDTD) were calculated as the differences between (R-pE) and (R-pE′), and (P-pA) and (P-pA′), respectively.

Results:

The mean EDTD and LDTD were 28.7 ± 10.6 ms and 21.2 ± 15.9 ms, respectively. Similarly, the mean time difference [(P-pA) - (P-pAr)] was 21.5 ± 14.1 ms. EDTD was not associated with age (r=0.15, p=NS), while LDTD was inversely correlated with age (r=-0.65, p<0.01). No significant differences were found for both EDTD and LDTD between genders.

Conclusion:

EDTD and LDTD, the temporal discordances between mitral annulus motion and trans-mitral flow, embody one of the earliest events at early- and late-diastole. Age is not associated with EDTD, but is accompanied by a decline in LDTD. With respect to gender, both EDTD and LDTD are not influenced.

Mitral annular plane systolic excursion (MAPSE) in shock: a valuable echocardiographic parameter in intensive care patients

BACKGROUND

Assessing left ventricular (LV) dysfunction by echocardiography in ICU patients is common. The aim of this study was to investigate mitral annular plane systolic excursion (MAPSE) in critically ill patients with shock and its relation to LV systolic and diastolic function, myocardial injury and to outcome.

METHODS

In a prospective, observational, cohort study we enrolled 50 patients with SIRS and shock despite fluid resuscitation. Transthoracic echocardiography (TTE) measuring LV function was performed within 12 hours after admission and daily for a 7-day observation period. TTE and laboratory measurements were related to 28-day mortality.

RESULTS

MAPSE on day 1 correlated significantly with LV ejection fraction (LVEF), tissue Doppler indices of LV diastolic function (é, E/é) and high-sensitive troponin T (hsTNT) (p< 0.001, p= 0.039, p= 0.009, p= 0.003 respectively) whereas LVEF did not correlate significantly with any marker of LV diastolic function or myocardial injury. Compared to survivors, non-survivors had a significantly lower MAPSE (8 [IQR 7.5-11] versus 11 [IQR 8.9-13] mm; p= 0.028). Other univariate predictors were age (p=0.033), hsTNT (p=0.014) and Sequential Organ Failure Assessment (SOFA) scores (p=0.007). By multivariate analysis MAPSE (OR 0.6 (95% CI 0.5- 0.9), p= 0.015) and SOFA score (OR 1.6 (95% CI 1.1- 2.3), p= 0.018) were identified as independent predictors of mortality. Daily measurements showed that MAPSE, as sole echocardiographic marker, was significantly lower in most days in non-survivors (p<0.05 at day 1-2, 4-6).

CONCLUSIONS

MAPSE seemed to reflect LV systolic and diastolic function as well as myocardial injury in critically ill patients with shock. The combination of MAPSE and SOFA added to the predictive value for 28-day mortality.

Left ventricular myocardial performance in patients with dengue hemorrhagic fever and thrombocytopenia as assessed by two-dimensional speckle tracking echocardiography

OBJECTIVES

We obtained longitudinal, radial and circumferential strains in patients with dengue hemorrhagic fever (DhF) and thrombocytopenia using two-dimensional (2D) speckle tracking echocardiography to analyze left ventricular (LV) myocardial performance.

METHODS

In this prospective study, 2D echocardiographic images of the left ventricle in the four-, three- and two-chamber views and parasternal short-axis views at the basal, mid and apical levels were obtained in 40 subjects: 20 patients (23 ± 8 years, 12 male) with DhF and thrombocytopenia and 20 healthy controls (23 ± 5 years, 11 male). Of the 20 patients, imaging was performed again in 19 at discharge after a hospital stay of 8 ± 1 days. Longitudinal, circumferential and radial strains were quantified and compared in an 18-segment model using a novel speckle tracking system.

RESULTS

Left ventricular global ejection fraction was reduced in patients with DhF at presentation as compared with controls (51.25 ± 0.96% vs. 59.32 ± 1.26%; p = 0.032). Peak longitudinal strain in patients with DhF was significantly attenuated in the subendocardial region compared with normal controls (p < 0.001). A significant increase in circumferential strain for patients with DhF was evident only in the subepicardial region (p = 0.009). Patients with DhF showed significantly higher radial strain than controls (p < 0.001). On multivariate analysis, subendocardial longitudinal strain independently predicted the duration of hospital stay in patients with DhF.

CONCLUSION

Assessment of speckle tracking echocardiography-derived LV mechanics helps in understanding myocardial mechanics in patients with DhF and thrombocytopenia. Identification of reduced LV longitudinal strain helps in understanding the mechanism of reduced LV myocardial performance seen in patients with DhF.

What is the primary source of discordance in strain measurement between vendors: imaging or analysis?

Strain imaging quantifies myocardial deformation in both overt and subclinical myocardial diseases. Strain values have been shown to vary between vendors. The aim of this study was to investigate whether this variation reflects differences of image characteristics or analysis software. We enrolled 45 patients (age 54 ± 14 years, 26 males) who underwent two echocardiograms on the same day with two different commercially available ultrasound systems. Three apical views were analyzed by two vendor-specific and two digital imaging and communications in medicine (DICOM)-based software packages. The results were compared in two ways; comparison of global longitudinal strain (GLS) by nine different combinations of ultrasound systems and strain software, and comparison of strains by wall, view and global levels. Comparison of GLS between two vendor-specific software packages yielded poor correlation (ρ = 0.35). The use of the same software on the images from different vendors was concordant (ρ = 0.74 and 0.64; bias = 0.0 and -0.5). There were no significant differences in correlation coefficients among the comparisons with DICOM-based software. There was no significant difference in correlation coefficients among three views (4CV vs. 3CV, p = 0.44; 4CV vs. 2CV, p = 0.47). Comparison of walls showed the septum to have the best correlation (ρ = 0.73), and the posterior wall (ρ = 0.31; p = 0.005 vs. septum) had the worst. Use of the same software to measure strain in images from different vendors minimizes the variation of GLS. Post-processing is the most important determinant in inter-vendor variation, with differences in acquisition having a small effect. These findings should be examined and confirmed with other combinations of ultrasound machines and deformation software.