Measurement of left ventricular mass by real-time three-dimensional echocardiography: validation against magnetic resonance and comparison with two-dimensional and m-mode measurements

Challenges in Echocardiography for the Diagnosis and Prognosis of Non-Ischemic Hypertensive Heart Disease

It has been well established that arterial hypertension is considered as a predominant risk factor for the development of cardiovascular diseases. Despite the link between arterial hypertension and cardiovascular diseases, arterial hypertension may directly affect cardiac function, leading to heart failure, mostly with preserved ejection fraction (HFpEF). There are echocardiographic findings indicating hypertensive heart disease (HHD), defined as altered cardiac morphology (left ventricular concentric hypertrophy, left atrium dilatation) and function (systolic or diastolic dysfunction) in patients with persistent arterial hypertension irrespective of the cardiac pathologies to which it contributes, such as coronary artery disease and kidney function impairment. In addition to the classical echocardiographic parameters, novel indices, like speckle tracking of the left ventricle and left atrium, 3D volume evaluation, and myocardial work in echocardiography, may provide more accurate and reproducible diagnostic and prognostic data in patients with arterial hypertension. However, their use is still underappreciated. Early detection of and prompt therapy for HHD will greatly improve the prognosis. Hence, in the present review, we shed light on the role of echocardiography in the contemporary diagnostic and prognostic approaches to HHD.

Accuracy of Devereaux and Teichholz formulas for left ventricular mass calculation in different geometric patterns: comparison with cardiac magnetic resonance imaging

Left ventricular (LV) myocardial mass is important in the evaluation of cardiac remodeling and requires accurate assessment when performed on linear measurements in two-dimensional echocardiography (Echo). We aimed to compare the accuracy of the Devereaux formula (DEV) and the Teichholz formula (TEICH) in calculating LV myocardial mass in Echo using cardiac magnetic resonance (CMR) as the reference method. Based on preceding mathematical calculations, we identified primarily LV size rather than wall thickness as the main source of bias between DEV and TEICH in a retrospective derivation cohort (n = 1276). Although LV mass from DEV and TEICH were correlated with CMR, TEICH did not show a proportional bias as did DEV (- 2 g/m2 vs. + 22 g/m2). This could be validated in an independent prospective cohort (n = 226) with symptomatic non-ischemic heart failure. DEV systematically overestimated LV mass in all tiers of LV remodeling as compared to TEICH. In conclusion, the TEICH method accounts for the changes in LV geometry with increasing LV mass and thus better reflects the different pattern of LV remodeling than the DEV method. This has important clinical implications, as TEICH may be more appropriate for use in clinical practice, rather than DEV, currently recommended.

Multimodality cardiovascular imaging in hypertension

PURPOSE OF THE REVIEW

Hypertension accounts for the largest proportion of cardiovascular (CV) mortality worldwide and its prevalence continues to rise. While prominent CV societies have offered strong recommendations on the management of hypertension in adults, the role of noninvasive CV imaging in the evaluation of hypertensive patients remains incompletely defined.

RECENT FINDINGS

Noninvasive imaging is a rapidly expanding field with a growing number of sophisticated and readily applicable modalities to assess how cardiac structure and function changes after periods of sustained, elevated blood pressure. Echocardiography remains the initial modality to screen these patients while developments in nuclear, computed tomography and cardiac magnetic resonance complement and expand investigations for alternative diagnoses that may complement or conflict with the diagnosis of left ventricular hypertrophy.

SUMMARY

In this review article, we summarize the application of echocardiography, nuclear imaging, cardiac computed tomography, and cardiac magnetic resonance imaging in the evaluation and management of hypertensive heart disease.

Hypertensive Heart Disease-The Imaging Perspective

Hypertensive heart disease (HHD) develops in response to the chronic exposure of the left ventricle and left atrium to elevated systemic blood pressure. Left ventricular structural changes include hypertrophy and interstitial fibrosis that in turn lead to functional changes including diastolic dysfunction and impaired left atrial and LV mechanical function. Ultimately, these changes can lead to heart failure with a preserved (HFpEF) or reduced (HFrEF) ejection fraction. This review will outline the clinical evaluation of a patient with hypertension and/or suspected HHD, with a particular emphasis on the role and recent advances of multimodality imaging in both diagnosis and differential diagnosis.

Structure, Property, and Performance of Catalyst Layers in Proton Exchange Membrane Fuel Cells

Catalyst layer (CL) is the core component of proton exchange membrane (PEM) fuel cells, which determines the performance, durability, and cost. However, difficulties remain for a thorough understanding of the CLs' inhomogeneous structure, and its impact on the physicochemical and electrochemical properties, operating performance, and durability. The inhomogeneous structure of the CLs is formed during the manufacturing process, which is sensitive to the associated materials, composition, fabrication methods, procedures, and conditions. The state-of-the-art visualization and characterization techniques are crucial to examine the CL structure. The structure-dependent physicochemical and electrochemical properties are then thoroughly scrutinized in terms of fundamental concepts, theories, and recent progress in advanced experimental techniques. The relation between the CL structure and the associated effective properties is also examined based on experimental and theoretical findings. Recent studies indicated that the CL inhomogeneous structure also strongly affects the performance and degradation of the whole fuel cell, and thus, the interconnection between the fuel cell performance, failure modes, and CL structure is comprehensively reviewed. An analytical model is established to understand the effect of the CL structure on the effective properties, performance, and durability of the PEM fuel cells. Finally, the challenges and prospects of the CL structure-associated studies are highlighted for the development of high-performing PEM fuel cells.

Graphical abstract

Clinical significance of myocardial contraction fraction in significant primary mitral regurgitation

BACKGROUND

The optimal timing for mitral valve (MV) surgery in asymptomatic patients with primary mitral regurgitation (MR) remains a matter of debate. Myocardial contraction fraction (MCF) - the ratio of the left ventricular (LV) stroke volume to that of the myocardial volume - is a volumetric measure of LV myocardial shortening independent of size or geometry.

AIM

To assess the relationship between MCF and outcome in patients with significant chronic primary MR due to prolapse managed in contemporary practice.

METHODS

Clinical, Doppler-echocardiographic and outcome data prospectively collected in 174 patients (mean age 62 years, 27% women) with significant primary MR and no or mild symptoms were analysed. The impact of MCF< or ≥30% on cardiac events (cardiovascular death, acute heart failure or MV surgery) was studied.

RESULTS

During an estimated median follow-up of 49 (22-77) months, cardiac events occurred in 115 (66%) patients. The 4-year estimates of survival free from cardiac events were 21±5% for patients with MCF <30% and 40±6% for those with ≥30% (P<0.001). MCF <30% was associated with a considerable increased risk of cardiac events after adjustment for established clinical risk factors, MR severity and current recommended class I triggers for MV surgery (adjusted hazard ratio: 2.33, 95% confidence interval: 1.51-3.58; P<0.001). Moreover, MCF<30% improved the predictive performance of models, with better global fit, reclassification and discrimination.

CONCLUSIONS

MCF<30% is strongly associated with occurrence of cardiac events in patients with significant primary MR due to prolapse. Further studies are needed to assess the direct impact of MCF on patient management and outcomes.

Determination of sources of error and improvement in accuracy of left ventricular mass measurement by echocardiography

Abnormal Left ventricular mass (LVM) prognosticates adverse cardiovascular events. Conventionally, LVM measured by echo assumes a prolate ellipsoid (PE) shape; however, it poorly correlates with reference standard of cardiac magnetic resonance imaging (CMR) derived LVM. PE model assumes LVL = 2 × LVID. We developed a new echo LVM formula based on LV length and tested for accuracy against CMR. A retrospective study of consecutive patients with an echocardiogram and CMR within 3 months. Derivation (n = 170) and validation cohorts (n = 54) were used to test the new formula. Following analysis of correlation of interventricular septum (IVS), LV internal dimension (LVID), posterior wall (PW) and LVL between echo and CMR, a novel paraboloid-shape linear regression (PLR) model was derived. LVM by both models were compared to CMR. Poor correlation observed between actual and assumed LVL (0.52 with CMR; 0.44 with echo). Strong correlation was noted between echo and CMR measured LVL, LVID, IVS (r > 0.80) and a moderate correlation with PW (r = 0.62). Strong correlation of LVL was harnessed to develop PLR model, which significantly decreased paired error in derivation cohort (from 64 ± 42 to 22 ± 21 gm) and validation cohort (from 63 ± 46 to 25 ± 18 gm). Furthermore, it demonstrates significant reduction in absolute, relative errors and variability along with superior correlation in both cohorts. Between echo and CMR, LVL demonstrates one of the best correlation among LV dimensions. The assumption, LVL = 2 × LVID appears inaccurate. PLR model incorporates LVL and significantly improves accuracy, reduces variability of LVM.

Phenotyping the hypertensive heart

Arterial hypertension remains the most frequent cardiovascular (CV) risk factor, and is responsible for a huge global burden of disease. Echocardiography is the first-line imaging method for the evaluation of cardiac damage in hypertensive patients and novel techniques, such as 2D and D speckle tracking and myocardial work, provide insight in subclinical left ventricular (LV) impairment that would not be possible to detect with conventional echocardiography. The structural, functional, and mechanical cardiac remodelling that are detected with imaging are intermediate stages in the genesis of CV events, and initiation or intensification of antihypertensive therapy in response to these findings may prevent or delay progressive remodelling and CV events. However, LV remodelling—especially LV hypertrophy—is not specific to hypertensive heart disease (HHD) and there are circumstances when other causes of hypertrophy such as athlete heart, aortic stenosis, or different cardiomyopathies need exclusion. Tissue characterization obtained by LV strain, cardiac magnetic resonance, or computed tomography might significantly help in the distinction of different LV phenotypes, as well as being sensitive to subclinical disease. Selective use of multimodality imaging may therefore improve the detection of HHD and guide treatment to avoid disease progression. The current review summarizes the advanced imaging tests that provide morphological and functional data about the hypertensive cardiac injury.

A new method to quantify left ventricular mass by 2D echocardiography

Increased left ventricular mass (LVM) is a strong independent predictor for adverse cardiovascular events, but conventional echocardiographic methods are limited by poor reproducibility and accuracy. We developed a novel method based on adding the mean wall thickness from the parasternal short axis view, to the left ventricular end-diastolic volume acquired using the biplane model of discs. The participants (n = 85) had various left ventricular geometries and were assessed using echocardiography followed immediately by cardiac magnetic resonance, as reference. We compared our novel two-dimensional (2D) method to various conventional one-dimensional (1D) and other 2D methods as well as the three-dimensional (3D) method. Our novel method had better reproducibility in intra-examiner [coefficients of variation (CV) 9% vs. 11–14%] and inter-examiner analysis (CV 9% vs. 10–20%). Accuracy was similar to the 3D method (mean difference ± 95% limits of agreement, CV): Novel: 2 ± 50 g, 15% vs. 3D: 2 ± 51 g, 16%; and better than the “linear” 1D method by Devereux (7 ± 76 g, 23%). Our novel method is simple, has considerable better reproducibility and accuracy than conventional “linear” 1D methods, and similar accuracy as the 3D-method. As the biplane model forms part of the standard echocardiographic protocol, it does not require specific training and provides a supplement to the modern echocardiographic report.

Necropsy Validation of a Novel Method for Left Ventricular Mass Quantification in Porcine Transthoracic and Transdiaphragmal Echocardiography

Introduction

Increased left ventricular mass (LVM) is one of the most powerful predictors of adverse cardiovascular events. Clinical evaluation requires reliable, accurate and reproducible echocardiographic LVM-quantification to manage patients. For this purpose, we have developed a novel two-dimensional (2D) method based on adding the mean wall thickness to the left ventricular volume acquired by the biplane method of disks, which has recently been validated in humans using cardiac magnetic resonance as reference value. We assessed the hypothesis that the novel method has better accuracy than conventional one-dimensional (1D) methods, when compared to necropsy LVM in pigs.

Materials and Methods

Echocardiography was performed during anesthesia in 34 Danish Landrace pigs, weight 47–59 kg. All pigs were euthanized, cardiac necropsy was performed and the left ventricle was trimmed and weighed for necropsy LVM. Trans-thoracic echocardiography was applied for parasternal images. Transdiaphragmal echocardiography was applied for the apical images, which are otherwise difficult to obtain in pigs. We compared the conventional 1D- and 2D-methods and the novel 2D-method to the LVM from cardiac necropsy.

Results

Necropsy LVM was 132 ± 11 g (mean ± SD). The novel method had better accuracy than other methods (mean difference ± 95% limits of agreement; coefficients of variation; standard error of the estimate, Pearson's correlation). Novel (−1 ± 20 g; 8%; 11 g; r = 0.70), Devereux (+26 ± 37 g; 15%; 33 g; r = 0.52), Area-Length (+27 ± 34 g; 13 %; 33 g; r = 0.63), Truncated Ellipsoid (+10 ± 30 g; 12%; 19 g; r = 0.63), biplane endo-/epicardial tracing (−3 ± 2 g; 10%; 14 g; r = 0.57). No proportional bias in linear regression was detected for any method, when compared to necropsy LVM.

Conclusion

We confirm high accuracy of the novel 2D-based method compared to conventional 1D/2D-methods.

Guide de Pratique Clinique. Prise en charge de l’hypertension artérielle chez l’adulte en Tunisie

Ce document a été réalisé dans le cadre d'une collaboration entre l'Instance Nationale de l’Évaluation et de l'Accréditation en Santé (INEAS), la Société Tunisienne de Cardiologie et de Chirurgie Cardiovasculaire (STCCCV) et la Caisse Nationale d’Assurance Maladie (CNAM).

Left Ventricular Mass Assessment by 1- and 2-Dimensional Echocardiographic Methods in Hemodialysis Patients: Changes in Left Ventricular Volume Using Echocardiography Before and After a Hemodialysis Session

RATIONALE & OBJECTIVE

Left ventricular (LV) mass (LVM) is a predictor of cardiovascular morbidity and mortality and commonly calculated using 1-dimensional (1D) echocardiographic methods. These methods are vulnerable to small measurement errors and LVM may wrongly change according to changes in LV volume (LVV). Less commonly used 2-dimensional (2D) methods can accommodate to the changes in LVV and may be a better alternative among patients receiving hemodialysis (HD) with large fluid fluctuations.

STUDY DESIGN

Observational study.

SETTING & PARTICIPANTS

Patients with end-stage kidney disease receiving HD.

EXPOSURE

One HD session.

ANALYTICAL APPROACH

Transthoracic echocardiography was performed right before and after HD. LVM was calculated using 1D (Devereux, Penn, and Teichholz) and 2D methods (truncated ellipsoid and area-length).

OUTCOMES

Significant differences in LVM after HD.

RESULTS

We compared dimensions, LVV and LVM, in 53 patients (mean age, 63 ± 15 years; 66% men). For each 1-L increase in ultrafiltration volume (UFV), LV internal diameter decreased 1.1 mm (95% CI, 0.5-1.7 mm; P = 0.001). Patients were divided into 2 groups by the median UFV of 1.6 L. Patients with UFV > 1.6 L had significant smaller LVV and LV internal diameter after HD. LVM calculated using 1D methods decreased according to changes in LVV. Conversely, LVM calculated using 2D methods was not significantly different after HD. No significant change in differences between diastolic - systolic myocardial thickness or LVM as assessed using 1D and 2D methods was observed before and after HD, indicating that LVM remained constant despite HD.

LIMITATIONS

We did not use contrast enhancement, 3-dimensional methods, or cardiac magnetic resonance.

CONCLUSIONS

LVM calculated using 2D methods, truncated ellipsoid and area-length, is less affected by fluctuations in fluid and LVV, in contrast to 1D methods. Complementary LVM calculation using 2D methods is encouraged, especially in patients with large fluid fluctuations in which increased LVM using a 1D method has been detected.

Position statement of the Interamerican Society of Cardiology (IASC) on the current guidelines for the prevention, diagnosis and treatment of arterial hypertension 2017-2020

OBJECTIVES

As an Inter-American Society we are convinced of the need to standardize the steps in which we diagnose, evaluate, treat and control hypertension, establishing guidelines and rules that should be adopted in all countries of Latin America, aimed at standardizing management and control of CV risk in order to achieve a substantial decrease in CV events.

METHODS

In the last four years important international guidelines for the diagnosis, management, treatment and control of arterial hypertension have been published. In America, mostly in mid- and low-income countries, hypertension is a major problem of public health, being the most important cardiovascular risk factor due to its great population impact. Therefore, it is crucial to dedicate all the possible efforts to increase substantially the number of hypertensive patients diagnosed in a given area, and to improve the percentage of controlled patients. This is a major necessity in order to reduce the morbidity and mortality for CVD in the Latin American region, although no guidelines takes the Latin American populations into account, and much less standardizes their diagnosis and management.

CONCLUSIONS

The Inter-American Society of Cardiology suggest the use of the blood pressure classification of the Latin American Society of Hypertension (LASH) and recommends the use of the SCORE System to stratify the global CV risk because this system has the capability to adapt the global risk by means of a correcting factor based on the ethnicity of the different native populations in America.

Role of advanced left ventricular imaging in adults with aortic stenosis

This review focuses on the available data regarding the utility of advanced left ventricular (LV) imaging in aortic stenosis (AS) and its potential impact for optimising the timing of aortic valve replacement. Ejection fraction is currently the only LV parameter recommended to guide intervention in AS. The cut-off value of 50%, recommended for decision-making in asymptomatic patients with AS, is currently under debate. Several imaging parameters have emerged as predictors of disease progression and clinical outcomes in this setting. Global longitudinal LV strain by speckle tracking echocardiography is useful for risk stratification of asymptomatic patients with severe AS and preserved LV ejection fraction. Its prognostic value was demonstrated in these patients, but further work is required to define the best thresholds to aid the decision-making process. The assessment of myocardial fibrosis is the most studied application of cardiac magnetic resonance in AS. The detection of replacement fibrosis by late gadolinium enhancement offers incremental prognostic information in these patients. Clinical implementation of this technique to optimise the timing of aortic valve intervention in asymptomatic patients is currently tested in a randomised trial. The use of T1 mapping techniques can provide an assessment of interstitial myocardial fibrosis and represents an expanding field of interest. However, convincing data in patients with AS is still lacking. All these imaging parameters have substantial potential to influence the management decision in patients with AS in the future, but data from randomised clinical trials are awaited to define their utility in daily practice.

Echocardiographic Left Ventricular Mass Estimation: Two-Dimensional Area-Length Method is Superior to M-Mode Linear Method in Swine Models of Cardiac Diseases

Echocardiography offers rapid and cost-effective estimations of left ventricular (LV) mass, but its accuracy in patients with cardiac disease remains unclear. LV mass was measured by M-mode-based linear method and two-dimensional echocardiography (2DE)-based area-length method in pig models and correlation with actual LV weight was assessed. Twenty-six normal, 195 ischemic heart disease (IHD), and 33 non-IHD HF pigs were included. A strong positive linear relationship to the actual LV weight was found with 2DE-based area-length method (r = 0.82, p < 0.001), whereas a moderate relationship was found with M-mode method in the overall population (r = 0.68, p < 0.001). Two correlation coefficients were significantly different (p < 0.001), and were driven mainly by incremental overestimation of LV mass in heavier hearts using the M-mode method. IHD and LV dilation were the factors contributing to overestimation using M-mode method. 2DE-based area-length method provides a better estimation of LV weight in swine models of HF, particularly in those with IHD.

Performance of a new fully automated transthoracic three-dimensional echocardiographic software for quantification of left cardiac chamber size and function: Comparison with 3 Tesla cardiac magnetic resonance

PURPOSE

To evaluate the accuracy and reproducibility of a new fully automated fast three-dimensional (3D) transthoracic echocardiography (TTE) software for the simultaneous assessment of left atrial (LA) volumes and LA ejection fraction (EF), left ventricular (LV) volumes, LV mass, and LVEF, and to compare the results obtained with a cardiac magnetic resonance (CMR) reference.

METHODS

We included retrospectively 56 patients (46 men; mean age 63 ± 13 years) in sinus rhythm who had had comprehensive 3D TTE and CMR examinations within 24 hours.

RESULTS

Despite a slight underestimation of LV and LA volumes, LVEF and LAEF were similar using CMR or 3DTTE (58% ± 16% vs 58% ± 12%; P = .65 and 45% ± 14% vs 46% ± 15%; P = .38, respectively) in the total population. Despite significant correlation between TTE and CMR measurements (r = 0.78; P < .001), 3D TTE underestimated LV mass (bias = -27 ± 35 g).

CONCLUSION

3D TTE using a new-generation fully automated software is a fast and reproducible imaging modality for simultaneous extensive quantification of left heart chambers size and function in routine practice. Potential underestimation of LA volume and LV mass, and of LVEF in patients with LVEF <50%, should be taken into consideration.

Accuracy of three-dimensional systolic dyssynchrony and sphericity indexes for identifying early left ventricular remodeling after acute myocardial infarction

Objective:

Left ventricle (LV) geometry and dyssynchrony are associated with LV remodeling after acute myocardial infarction (AMI). The aim of this prospective study was to assess the diagnostic value of new three-dimensional echocardiography (3DE) parameters [sphericity (SI) and systolic dyssynchrony indexes (SDI)] for the prediction of LV remodeling after AMI and to compare them with two-dimensional echocardiography (2DE) parameters.

Methods:

2DE and 3DE were performed in 75 patients with AMI within 3 days from the onset of MI and 6 months later. LV remodeling was defined as a ≥15% increase in the LV end-diastolic volume (EDV) at follow-up. 3D SI was calculated by dividing EDV by the volume of a sphere whose diameter was derived from the major end-diastolic LV long axis. SDI was considered as a standard deviation of the time from cardiac cycle onset to minimum systolic volume in 16 LV segments.

Results:

LV remodeling was identified in 34 (45%) patients using the 2DE method and in 22 (29%) patients using the 3DE method. Evaluated 3DE parameters, such as EDV [area under the receiver operating characteristic (ROC) curve (AUC) 0.742, sensitivity 71%, specificity 79%], end-systolic volume (AUC 0.729, sensitivity 69%, specificity 78%), SDI (AUC 0.777, sensitivity 73%, specificity 77%), and SI, had significant prognostic value for LV remodeling. According to the AUC, the highest predictive value had 3D SI (AUC 0.957, sensitivity 90%, specificity 91%).

Conclusion:

3DE parameters, especially 3D SI and SDI, play important roles in the prediction of LV remodeling after AMI and can be used in clinical practice.

Cardiac left ventricular myocardial tissue density, evaluated by computed tomography and autopsy

BACKGROUND

Left ventricular mass (LVM) is an independent risk factor for the prediction of cardiac events. Its assessment is a clinically important diagnostic procedure in cardiology and may be performed by Computed Tomography (CT). The aim of this study was to assess the correlation between the cardiac left ventricular shell volume (LVShV) determined by postmortem Computed Tomography (PMCT) and the anatomic LVM obtained at autopsy and to calculate the myocardial tissue density.

METHODS

A total of 109 deceased individuals were examined with a 64-slice CT scanner and LVShV was determined. At autopsy, the left ventricle was dissected and weighted. The correlation between LVShV and the anatomic LVM was analysed. Asymmetric left ventricular (LV) hypertrophy was recorded. Inter-observer variability was evaluated, and a density value for myocardial tissue was calculated.

RESULTS

The mean age of the deceased was 55 ± 16 years, and 58% was men. We found 30 cases of asymmetric LV hypertrophy. A highly positive correlation existed between LVShV and anatomic LVM (r = 0.857; p < 0.0001), regardless of hypertrophy, asymmetric hypertrophy and gender. The mean difference in the inter-observer variability for LVShV assessment was - 4.4 ml (95% CI: -26.4; 17.6). A linear regression analysis was performed, resulting in a value of 1.265 g/ml for myocardial tissue density. Applying the hitherto used myocardial tissue density of 1.055 g/ml underestimated the anatomic LVM by 18.1% (p < 0.0001).

CONCLUSION

PMCT is a helpful tool for the assessment of LVM, and LVShV is highly correlated with LVM as assessed by subsequent autopsy. The correlation between the two was independent of gender, hypertrophy and LV asymmetric hypertrophy. We found a higher myocardial tissue density of 1.265 g/ml compared to previous studies. We show that PMCT combined with autopsy may contribute not only to anatomical but also clinical knowledge.

Agreement of 2D transthoracic echocardiography with cardiovascular magnetic resonance imaging after ST-elevation myocardial infarction

BACKGROUND

This study was designed to investigate the agreement of 2D transthoracic echocardiography (2D TTE) with cardiovascular magnetic resonance imaging (CMR) in a contemporary population of ST-elevation myocardial infarction (STEMI) patients.

METHODS

In this subanalysis of the GIPS-III trial, a randomized controlled trial investigating the administration of metformin in STEMI patients to prevent reperfusion injury, we studied 259 patients who underwent same-day CMR and 2D TTE assessments four months after hospitalization for a first STEMI. Bland-Altman analyses were performed to assess agreement between LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV ejection fraction (LVEF), and LV mass measurements. Sensitivity and specificity of 2D TTE to detect categories of LVEF (≤35%, 35-50%, ≥50%) was determined. Linear regression of absolute differences in measurements between imaging modalities was used to investigate whether patient characteristics impact measurement bias.

RESULTS

Pairwise difference (bias) and 95% limits of agreement between CMR and 2D TTE measurements were +84 (37, 147) ml for LVEDV, +39 (6, 85) ml for LVESV, -1.1 ± 13.5% for LVEF, and -75 (-154, -14) g for LV mass. Sensitivity and specificity of 2D TTE to detect subjects with moderately depressed LVEF (35-50%) as measured by CMR were 52% and 88% respectively. We observed a significant effect of enzymatic infarct size on bias between 2D TTE and CMR in measuring LVESV and LVEF (P = 0.029, P = 0.001 respectively), of age and sex on bias between 2D TTE and CMR in measuring LV mass (P = 0.027, P < 0.001) and LVEDV (P = 0.001, P = 0.039), and of heart rate on bias between 2D TTE and CMR in LV volume measurements (P = 0.004, P = 0.016).

CONCLUSIONS

Wide limits of agreement, underestimation of LV volumes and overestimation of LV mass was observed when comparing 2D TTE to CMR. Enzymatic infarct size, age, sex, and heart rate are potential sources of bias between imaging modalities.

Evaluation of Left Ventricular Systolic Function and Mass in Primary Hypertensive Patients by Echocardiography

Hypertension is an independent risk factor for cardiovascular diseases. The accurate evaluation of cardiovascular risk is of paramount importance in the management of hypertensive patients. Conventional echocardiographic methods have provided the assessment of left ventricular systolic function and mass for many years. Tissue Doppler imaging, 3-dimensional echocardiography, and speckle tracking echocardiography are newer echocardiographic modalities for the left ventricular systolic function and mass quantification. The major emphasis of this review is to evaluate the left ventricular systolic function and mass by conventional and newly developed echocardiographic in hypertensive patients.

Automated, machine learning-based, 3D echocardiographic quantification of left ventricular mass

BACKGROUND

Although 3D echocardiography (3DE) circumvents many limitations of 2D echocardiography by allowing direct measurements of left ventricular (LV) mass, it is seldom used in clinical practice due to time-consuming analysis. A recently developed 3DE machine learning (ML) approach allows automated determination of LV mass. We aimed to evaluate the accuracy of this new approach by comparing it to cardiac magnetic resonance (CMR) reference and to conventional 3DE volumetric analysis.

METHODS

We prospectively studied 23 patients who underwent 3DE (Philips EPIQ) and CMR imaging on the same day. Single-beat wide-angle 3D datasets of the left ventricle were acquired. LV mass was quantified using the new automated software (Philips HeartModel) with manual corrections when necessary and using conventional volumetric analysis (TomTec). CMR analysis was performed by manual slice-by-slice tracing of LV endo- and epicardial boundaries. Reproducibility of the ML approach was assessed using repeated measurements and quantified by intra-class correlation (ICC) and coefficients of variation (CoV).

RESULTS

Automated LV mass measurements were feasible in 20 patients (87%). The results were similar to CMR-derived values (Bland-Altman bias 5 g, limits of agreement ±37 g) and also to the conventional 3DE analysis (bias 7 g, ±27 g). Processing time was considerably shorter: 1.02 ± 0.24 minutes (CMR: 2.20 ± 0.13 minutes; TomTec: 2.36 ± 0.09 minutes), although manual corrections were performed in most patients. Repeated measurements showed high reproducibility: ICC = 0.99; CoV = 4 ± 5%.

CONCLUSIONS

3D Echocardiography analysis of LV mass using novel ML-based algorithm is feasible, fast, and accurate and may thus facilitate the incorporation of 3DE measurements of LV mass into clinical practice.

2018 ESC/ESH Guidelines for the management of arterial hypertension: The Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension: The Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension

: Document reviewers: Guy De Backer (ESC Review Co-ordinator) (Belgium), Anthony M. Heagerty (ESH Review Co-ordinator) (UK), Stefan Agewall (Norway), Murielle Bochud (Switzerland), Claudio Borghi (Italy), Pierre Boutouyrie (France), Jana Brguljan (Slovenia), Héctor Bueno (Spain), Enrico G. Caiani (Italy), Bo Carlberg (Sweden), Neil Chapman (UK), Renata Cifkova (Czech Republic), John G. F. Cleland (UK), Jean-Philippe Collet (France), Ioan Mircea Coman (Romania), Peter W. de Leeuw (The Netherlands), Victoria Delgado (The Netherlands), Paul Dendale (Belgium), Hans-Christoph Diener (Germany), Maria Dorobantu (Romania), Robert Fagard (Belgium), Csaba Farsang (Hungary), Marc Ferrini (France), Ian M. Graham (Ireland), Guido Grassi (Italy), Hermann Haller (Germany), F. D. Richard Hobbs (UK), Bojan Jelakovic (Croatia), Catriona Jennings (UK), Hugo A. Katus (Germany), Abraham A. Kroon (The Netherlands), Christophe Leclercq (France), Dragan Lovic (Serbia), Empar Lurbe (Spain), Athanasios J. Manolis (Greece), Theresa A. McDonagh (UK), Franz Messerli (Switzerland), Maria Lorenza Muiesan (Italy), Uwe Nixdorff (Germany), Michael Hecht Olsen (Denmark), Gianfranco Parati (Italy), Joep Perk (Sweden), Massimo Francesco Piepoli (Italy), Jorge Polonia (Portugal), Piotr Ponikowski (Poland), Dimitrios J. Richter (Greece), Stefano F. Rimoldi (Switzerland), Marco Roffi (Switzerland), Naveed Sattar (UK), Petar M. Seferovic (Serbia), Iain A. Simpson (UK), Miguel Sousa-Uva (Portugal), Alice V. Stanton (Ireland), Philippe van de Borne (Belgium), Panos Vardas (Greece), Massimo Volpe (Italy), Sven Wassmann (Germany), Stephan Windecker (Switzerland), Jose Luis Zamorano (Spain).The disclosure forms of all experts involved in the development of these Guidelines are available on the ESC website www.escardio.org/guidelines.

Current Clinical Applications of Three-Dimensional Echocardiography: When the Technique Makes the Difference

Advances in ultrasound, computer, and electronics technology have permitted three-dimensional echocardiography (3DE) to become a clinically viable imaging modality, with significant impact on patient diagnosis, management, and outcome. Thanks to the inception of a fully sampled matrix transducer for transthoracic and transesophageal probes, 3DE now offers much faster and easier data acquisition, immediate display of anatomy, and the possibility of online quantitative analysis of cardiac chambers and heart valves. The clinical use of transthoracic 3DE has been primarily focused, albeit not exclusively, on the assessment of cardiac chamber volumes and function. Transesophageal 3DE has been applied mostly for assessing heart valve anatomy and function. The advantages of using 3DE to measure cardiac chamber volumes derive from the lack of geometric assumptions about their shape and the avoidance of the apical view foreshortening, which are the main shortcomings of volume calculations from two-dimensional echocardiographic views. Moreover, 3DE offers a unique realistic en face display of heart valves, congenital defects, and surrounding structures allowing a better appreciation of the dynamic functional anatomy of cardiac abnormalities in vivo. Offline quantitation of 3DE data sets has made significant contributions to our mechanistic understanding of normal and diseased heart valves, as well as of their alterations induced by surgical or interventional procedures. As reparative cardiac surgery and transcatheter procedures become more and more popular for treating structural heart disease, transesophageal 3DE has expanded its role as the premier technique for procedure planning, intra-procedural guidance, as well as for checking device function and potential complications after the procedure.

Left Ventricular Myocardial Segmentation in 3-D Ultrasound Recordings: Effect of Different Endocardial and Epicardial Coupling Strategies

Cardiac volume/function assessment remains a critical step in daily cardiology, and 3-D ultrasound plays an increasingly important role. Though development of automatic endocardial segmentation methods has received much attention, the same cannot be said about epicardial segmentation, in spite of the importance of full myocardial segmentation. In this paper, different ways of coupling the endocardial and epicardial segmentations are contrasted and compared with uncoupled segmentation. For this purpose, the B-spline explicit active surfaces framework was used; 27 3-D echocardiographic images were used to validate the different coupling strategies, which were compared with manual contouring of the endocardial and epicardial borders performed by an expert. It is shown that an independent segmentation of the endocardium followed by an epicardial segmentation coupled to the endocardium is the most advantageous. In this way, a framework for fully automatic 3-D myocardial segmentation is proposed using a novel coupling strategy.

Image-Derived Assessment of Left Ventricular Mass in Fetal Myocardial Hypertrophy by 4-Dimensional Echocardiography: An In Vitro Study

OBJECTIVES

This study tested the accuracy of new 4-dimensional fetal echocardiography to evaluate left ventricular (LV) mass in an experimental model of fetal myocardial hypertrophy.

METHODS

Ten fresh rabbit hearts were studied. Fetal myocardial hypertrophy was simulated by fixing different amounts of myocardial tissue to the LV epicardium. A small latex balloon was mounted on vinyl tubing and fixed within each LV cavity. The proximal end of the tube was attached to a pulsatile pump apparatus. The pump was calibrated to deliver stroke volumes of 2 and 4 mL at stroke rates of 60 and 120 beats per minute (bpm). Four-dimensional data were acquired and analyzed with quantification software. Reference values for LV mass were determined by the displacement method.

RESULTS

Echo-derived measurements of LV mass showed good correlations with reference values at all stroke rates and stroke volumes: at 2 mL and 60 bpm, r = 0.95; at 2 mL and 120 bpm, r = 0.95; at 4 mL and 60 bpm, r = 0.93; and at 4 mL and 120 bpm, r = 0.95 (P< .01 for all values). There was also excellent interobserver (r = 0.98; mean difference of -0.32 g; -4.4% of the mean) and intraobserver (r = 0.98; mean difference of -0.28 g; -3.8% of the mean) agreement.

CONCLUSIONS

In this controlled in vitro study, high-resolution 4-dimensional echocardiography was shown to accurately assess LV mass and have the potential to evaluate fetal myocardial hypertrophy.

Recommendations on the Use of Echocardiography in Adult Hypertension: A Report from the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE)

Hypertension remains a major contributor to the global burden of disease. The measurement of blood pressure continues to have pitfalls related to both physiological aspects and acute variation. As the left ventricle (LV) remains one of the main target organs of hypertension, and echocardiographic measures of structure and function carry prognostic information in this setting, the development of a consensus position on the use of echocardiography in this setting is important. Recent developments in the assessment of LV hypertrophy and LV systolic and diastolic function have prompted the preparation of this document. The focus of this work is on the cardiovascular responses to hypertension rather than the diagnosis of secondary hypertension. Sections address the pathophysiology of the cardiac and vascular responses to hypertension, measurement of LV mass, geometry, and function, as well as effects of treatment.

Discrepancies in Left Ventricular Mass Calculation Based on Echocardiography and Cardiovascular Magnetic Resonance Measurements in Patients with Left Ventricular Hypertrophy

BACKGROUND

Increased left ventricular (LV) mass is associated with adverse cardiovascular outcomes, and its accurate assessment is important. The aim of this study was to analyze the degree of difference among various methods of LV mass calculation based on transthoracic echocardiographic (TTE) measurements and cardiovascular magnetic resonance (CMR) measurements, especially in patients with aortic stenosis with varying degrees of LV hypertrophy (LVH). The mechanism underlying this disagreement was also investigated.

METHODS

Ninety-nine patients with moderate to severe aortic stenosis and 33 control subjects matched for age, sex, body weight, and height were enrolled in this prospective observational cohort study. All patients underwent TTE and CMR imaging. LV mass index (LVMI) was calculated using three formulas on the basis of TTE measurements (the Penn-cube, American Society of Echocardiography [ASE], and Teichholz methods) and compared with measurements obtained using CMR, the reference method.

RESULTS

Although all methods calculated using TTE measurements showed good correlations with CMR measurements, LVMI measured using the Penn-cube and ASE methods tended to be larger than LVMI measured using CMR (difference in LVMI by the Penn-cube and ASE methods, 59.3 ± 29.7 and 30.6 ± 22.3 g/m², respectively). This tendency decreased with the Teichholz method (difference in LVMI by the Teichholz method, 22.9 ± 19.1 g/m²). The degree of LVMI overestimation was significantly different among the three methods (P < .001 by one-way analysis of variance), which was more significant in patients with LVH, especially with the Penn-cube method (differences between CMR and TTE measurements in patients with aortic stenosis and LVH, 66.3 ± 34.8 vs 31.2 ± 26.6 vs 15.5 ± 20.9 g/m² for the Penn-cube, ASE, and Teichholz methods, respectively; P < .001 with post hoc Tukey analysis). There was a good correlation between LVMI and LV diameter-to-length ratio (r = 0.468, P < .001), which suggested that the left ventricle takes on a more globular shape with the increase of LVMI, resulting in a significant deviation from the basic assumptions on which the Penn-cube and ASE methods were built.

CONCLUSIONS

Current methods of calculating LVMI from echocardiographic measurements carry a tendency to measure LVMI larger than methods based on CMR measurements, which was more significant in patients with LVH. The change of the left ventricle's shape with LVH may be a plausible explanation for this, and a correction method may be needed when calculating LVMI from echocardiographic measurements, especially in patients with LVH and smaller body size.

Left Ventricular Hypertrophy in Chronic Kidney Disease Patients: From Pathophysiology to Treatment

Cardiovascular diseases represent the main causes of morbidity and mortality in patients with chronic kidney disease (CKD). According to a well-established classification, cardiovascular involvement in CKD can be set in the context of cardiorenal syndrome type 4. Left ventricular hypertrophy (LVH) represents a key feature to provide an accurate picture of systolic-diastolic left heart involvement in CKD patients. Cardiovascular involvement is present in about 80% of prevalent hemodialysis patients, and it is evident in CKD patients since stage IIIb-IV renal disease (according to the K/DOQI CKD classification). According to the definition of cardiorenal syndrome type 4, kidney disease is detected before the development of heart failure, although timing of the diagnosis is not always possible. The evaluation of LVH is a bit heterogeneous, and few standard imaging methods can provide the accuracy of either CT- or MRI-derived left ventricular mass. Key principles in the treatment of LVH in CKD patients are mainly based on anemia and blood pressure control, together with the management of secondary hyperparathyroidism and sudden cardiac death prevention. This review is mainly focused on the clinical aspects of CKD-related LVH to provide practical guidelines both for cardiologists and nephrologists in the daily clinical approach to CKD patients.

Role of echocardiography in clinical hypertension

Hypertension is a major and correctable cardiovascular risk factor. The correct diagnosis of hypertension and precise assessment of cardiovascular risk are essential to give proper treatment in patients with hypertension. Although echocardiography is the second-line study in the evaluation of hypertensive patients, it gives many clues suggesting bad prognosis associated with hypertension, including increased left ventricular (LV) mass, decreased LV systolic function, impaired LV diastolic function, and increased left atrial size and decreased function. Along with conventional echocardiographic methods, tissue Doppler imaging, three-dimensional echocardiography, and strain echocardiography are newer echocardiographic modalities in the evaluation of hypertensive patients in the current echocardiographic laboratories. Understanding conventional and newer echocardiographic parameters is important in the diagnosis and assessment of cardiovascular risk in hypertensive patients.

Prognostic value of LV deformation parameters using 2D and 3D speckle-tracking echocardiography in asymptomatic patients with severe aortic stenosis and preserved LV ejection fraction

OBJECTIVES

The objective of this study was to determine which strain component assessed by 2-dimensional speckle-tracking echocardiography (2DSTE) and 3-dimensional speckle-tracking echocardiography (3DSTE) was the most powerful predictor for future major adverse cardiac events (MACE) in asymptomatic patients with severe aortic stenosis (AS).

BACKGROUND

Ongoing debate exists regarding the appropriateness of early surgery in asymptomatic severe AS and preserved left ventricular ejection fraction (LVEF). Previous studies showed that 2-dimensional global longitudinal strain (2DGLS) was a significant predictor in asymptomatic severe AS patients. However, the prognostic utility of 3DSTE-derived multidirectional strain parameters has not been investigated in these patients.

METHODS

We enrolled 104 asymptomatic severe AS patients (indexed aortic valve area <0.6 cm(2)/m(2)) and preserved LVEF and performed strain analysis using both 2DSTE and 3DSTE. Two-dimensional and 3-dimensional global longitudinal, circumferential, and radial strain and global 3-dimensional strain were measured in each patient. All patients were followed to record MACE.

RESULTS

During a median follow-up of 373 days, MACE developed in 33 patients (32%). 2DGLS (-14.7 ± 3.3 vs. -16.3 ± 3.3, p = 0.0168), 3DGLS (-13.5 ± 2.5 vs. -16.1 ± 2.4, p < 0.0001) and 3-dimensional global radial strain (3DGRS) (35.9 ± 4.5 vs. 38.1 ± 4.4, p = 0.0209) were significantly impaired in patients with MACE compared with those without MACE. Kaplan-Meier analysis showed 2DGLS (cutoff: -17.0%), 3DGLS (cutoff: -14.5%), and 3DGRS (cutoff: 39.0%) provide a significant difference in MACE rate. Receiver-operating characteristic analysis revealed that the area under the curve of 3DGLS for MACE (0.78) was significantly larger than that of 2DGLS (0.62, p = 0.0044) and 3DGRS (0.66, p = 0.0069). Separate multivariate analysis revealed 3DGLS was only significant as independent predictor for future MACE after correcting for mean pressure gradient and left ventricular mass index.

CONCLUSIONS

3DGLS is the most robust index for predicting future adverse cardiac events in asymptomatic severe AS patients with preserved LVEF.

The clinical benefits of adding a third dimension to assess the left ventricle with echocardiography

Three-dimensional echocardiography is a novel imaging technique based on acquisition and display of volumetric data sets in the beating heart. This permits a comprehensive evaluation of left ventricular (LV) anatomy and function from a single acquisition and expands the diagnostic possibilities of noninvasive cardiology. It provides the possibility of quantitating geometry and function of LV without preestablished assumptions regarding cardiac chamber shape and allows an echocardiographic assessment of the LV that is less operator-dependent and therefore more reproducible. Further developments and improvements for widespread routine applications include higher spatial and temporal resolution to improve image quality, faster acquisition, processing and reconstruction, and fully automated quantitative analysis. At present, three-dimensional echocardiography complements routine 2DE in clinical practice, overcoming some of its limitations and offering additional valuable information that has led to recommending its use for routine assessment of the LV of patients in whom information about LV size and function is critical for their clinical management.

Comparison of three-dimensional echocardiographic findings to those of magnetic resonance imaging for determination of left ventricular mass in patients with ischemic and non-ischemic cardiomyopathy

The standard echocardiographic evaluation of left ventricular (LV) mass, particularly in ischemic cardiomyopathy (IC) is challenging because it is based on geometric assumptions. The aim of this study was to assess the accuracy of LV mass calculation using echocardiographic modalities compared with cardiac magnetic resonance (CMR) in IC and in nonischemic cardiomyopathy (non-IC). Echocardiography was performed in 104 patients (mean age 55 ± 15 years) referred for CMR: 63 with IC and 41 with non-IC. CMR, M-mode echocardiography, 2-dimensional echocardiography, and 3-dimensional echocardiography (3DE) were analyzed using standard commercial tools to obtain LV mass. LV mass on 3DE showed a higher correlation with CMR than 2-dimensional echocardiography (r = 0.87 vs r = 0.70, p <0.001). M-mode echocardiography overestimated LV mass (bias +30%) and 2-dimensional echocardiography underestimated LV mass (bias -11%), whereas measurements on 3DE showed only minimal bias (-2%). LV mass on 3DE in non-IC showed a significantly higher correlation with CMR than in IC (r = 0.92 vs r = 0.84, z = 2.3, p <0.05). In non-IC, the mean difference was -2 g (-1% of the mean), with 95% limits of agreement of ±33 g (±19% of the mean). In IC, the mean difference was -7 g (-4% of the mean), with limits of agreement of ±56 g (±31% of the mean). There was a correlation between the absolute LV mass differences (3DE derived and CMR derived) and scar percentage (infarcted mass/total LV mass) using delayed-hyperenhancement images (r = 0.40, p <0.05). The net reclassification index with 3DE was +16% for concentric LV hypertrophy. In conclusion, the most accurate and reliable echocardiographic measurement of LV mass is 3DE, but underestimation and variability remain challenges in IC.

Usefulness of real-time 3-dimensional echocardiography to identify and quantify left ventricular dyssynchrony in patients with Kawasaki disease

OBJECTIVES

The role of left ventricular (LV) dyssynchrony in Kawasaki disease is unknown. This study sought to establish values for real-time 3-dimensional (3D) echocardiographically derived LV dyssynchrony parameters and identify and quantify LV dyssynchrony in patients with Kawasaki disease.

METHODS

Forty patients hospitalized for Kawasaki disease were analyzed retrospectively, and 40 sex- and age-matched healthy control volunteers were also enrolled. The systolic dyssynchrony index (percentage of the cardiac cycle) from 16 and 12 LV segments on real-time 3D echocardiography was analyzed to calculate LV dyssynchrony (defined as the standard deviation of the time to reach the minimum systolic volume for 16 LV segments) according to a 17-segment model. We analyzed the 3D LV ejection fraction (LVEF), end-diastolic volume, and end-systolic volume in the patients with Kawasaki disease compared to the controls.

RESULTS

The 16-segment systolic dyssynchrony index ± SD was significantly higher in the patients with Kawasaki disease: 2.73% ± 0.96% compared to 2.01% ± 0.85% in the controls (P < .05). The 12-segment systolic dyssynchrony index in the patients with Kawasaki disease was 2.65% ± 0.93% compared to 1.98% ± 0.81% in the controls (P< .05). Patients with Kawasaki disease and an LVEF of less than 50% had a significantly higher systolic dyssynchrony index compared to patients with an LVEF of 50% or greater (2.89% ± 0.79% versus 2.26% ± 0.73%; P < .05). The LVEF measured by echocardiography was decreased in the patients with Kawasaki disease, and global systolic function was impaired. The LVEF measured by a biplane method was sufficiently related to the LVEF measured by echocardiography.

CONCLUSIONS

Real-time 3D echocardiography is a noninvasive and feasible method for identifying and evaluating LV dyssynchrony in children with Kawasaki disease. Left ventricular dyssynchrony is significantly impaired and related to LV systolic function in patients with Kawasaki disease.

Left-ventricular structure in the Southall And Brent REvisited (SABRE) study: explaining ethnic differences

Cardiometabolic risk is elevated in South Asians and African Caribbeans compared with Europeans, yet whether this is associated with ethnic differences in left-ventricular structure is unclear. Conventional M-mode or 2-dimensional echocardiography may be misleading, because they calculate left-ventricular mass and remodeling using geometric assumptions. Left-ventricular structure was compared in a triethnic population-based cohort using conventional and 3-dimensional echocardiography on 895 individuals (aged 55-85 years; 427 European, 325 South Asian, 143 African Caribbean). Left-ventricular mass was indexed, and left-ventricle remodeling index and relative wall thickness were calculated. Anthropometry, blood pressure, and fasting bloods were measured. Three-dimensional left-ventricular mass index did not differ between Europeans (mean ± SE, 29.8 ± 0.3 g/m(2.7)) and African Caribbeans (29.9 ± 0.5 g/m(2.7); P=0.9), but it was significantly lower in South Asians (28.1 ± 0.4 g/m(2.7); P<0.0001) compared with Europeans. These findings persisted on multivariate adjustment. In contrast, conventional left-ventricle mass index was significantly higher in African Caribbeans (46.4 ± 0.9 g/m(2.7)) than in Europeans (41.9 ± 0.5 g/m(2.7); P<0.0001). Left-ventricle remodeling index was the highest in African Caribbeans and the lowest in South Asians. Relative wall thickness was also higher in African Caribbeans, but no different in South Asians, compared with Europeans. Differences in left-ventricle remodeling index were attenuated by adjustment for cardiometabolic factors between African Caribbeans and Europeans only. In conclusion, left-ventricular mass is lower in South Asians and equivalent in African Caribbeans compared with Europeans, even when cardiometabolic risk factors are accounted for. Left-ventricular remodeling rather than hypertrophy may explain the increased risk of heart failure in people of African Caribbean origin.