The Role of Automated 3D Echocardiography for Left Ventricular Ejection Fraction Assessment

Aortic stenosis and right ventricular dysfunction

At the present time, right ventricular function in patients with aortic stenosis is insufficiently taken into account in the decision-making process of aortic valve replacement. The aim of our study was to evaluate significance of right ventricular dysfunction in patients with severe aortic stenosis by modern 3D echocardiographic methods. This is prospective analysis of 68 patients with severe high and low-gradient aortic stenosis. We evaluated function of left and right ventricle on the basis of 3D reconstruction. Enddiastolic, endsystolic volumes, ejection fraction and stroke volumes of both chambers were assessed. There were more patients with right ventricular dysfunction in low-gradient group (RVEF < 45%) than in the high-gradient group (63.6% vs 39%, p = 0.02). Low-gradient patients had worse right ventricular function than high-gradient patients (RVEF 36% vs 46%, p = 0.02). There wasn't any significant correlation between the right ventricular dysfunction and pulmonary hypertension (r = - 0.25, p = 0.036). There was significant correlation between left and right ejection fraction (r = 0.78, p < 0.0001). Multiple regression analysis revealed that the only predictor of right ventricular function is the left ventricular function. According to our results we can state that right ventricular dysfunction is more common in patients with low-gradient than in high-gradient aortic stenosis and the only predictor of right ventricular dysfunction is left ventricular dysfunction, probably based on ventriculo-ventricular interaction. Pulmonary hypertension in patients with severe AS does not predict right ventricular dysfunction.

Echocardiography Core Laboratory Validation of a Novel Vendor-Independent Web-Based Software for the Assessment of Left Ventricular Global Longitudinal Strain

BACKGROUND

Global longitudinal strain (GLS) is an accurate and reproducible parameter of left ventricular (LV) systolic function which has shown meaningful prognostic value. Fast, user-friendly, and accurate tools are required for its widespread implementation. We aim to compare a novel web-based tool with two established algorithms for strain analysis and test its reproducibility.

METHODS

Thirty echocardiographic datasets with focused LV acquisitions were analyzed using three different semi-automated endocardial GLS algorithms by two readers. Analyses were repeated by one reader for the purpose of intra-observer variability. CAAS Qardia (Pie Medical Imaging) was compared with 2DCPA and AutoLV (TomTec).

RESULTS

Mean GLS values were -15.0 ± 3.5% from Qardia, -15.3 ± 4.0% from 2DCPA, and -15.2 ± 3.8% from AutoLV. Mean GLS between Qardia and 2DCPA were not statistically different (p = 0.359), with a bias of -0.3%, limits of agreement (LOA) of 3.7%, and an intra-class correlation coefficient (ICC) of 0.88. Mean GLS between Qardia and AutoLV were not statistically different (p = 0.637), with a bias of -0.2%, LOA of 3.4%, and an ICC of 0.89. The coefficient of variation (CV) for intra-observer variability was 4.4% for Qardia, 8.4% 2DCPA, and 7.7% AutoLV. The CV for inter-observer variability was 4.5%, 8.1%, and 8.0%, respectively.

CONCLUSIONS

In echocardiographic datasets of good image quality analyzed at an independent core laboratory using a standardized annotation method, a novel web-based tool for GLS analysis showed consistent results when compared with two algorithms of an established platform. Moreover, inter- and intra-observer reproducibility results were excellent.

Fully Automated Mouse Echocardiography Analysis Using Deep Convolutional Neural Networks

Echocardiography (echo) is a translationally relevant ultrasound imaging modality widely used to assess cardiac structure and function in preclinical models of heart failure (HF) during research and drug development. Though echo is a very valuable tool, the image analysis is a time consuming, resource demanding process, and is susceptible to inter-reader variability. Recent advancements in deep learning have enabled researchers to automate image processing and reduce analysis time and inter-reader variability in the field of medical imaging. In the present study, we developed a fully automated tool - Mouse Echo Neural Net (MENN) - for the analysis of both long axis brightness (B)-mode and short axis motion (M)-mode images of the left ventricle. MENN is a series of fully convolutional neural networks that were trained and validated using manually segmented B-mode and M-mode echo images of the left ventricle. The segmented images were then used to compute cardiac structural and functional metrics. The performance of MENN was further validated in two preclinical models of HF. MENN achieved excellent correlations (Pearson's r = 0.85 to 0.99) and good to excellent agreement between automated and manual analyses. Further inter-reader variability analysis showed that MENN has better agreements with an expert analyst than both a trained analyst and a novice. Notably, the use of MENN reduced manual analysis time by >92%. In conclusion, we developed an automated echocardiography analysis tool that allows for fast and accurate analysis of B-mode and M-mode mouse echo data and mitigates the issue of inter-reader variability in manual analysis.

Heart Model A.I. Three-Dimensional Echocardiographic Evaluation of Left Ventricular Function and Parameter Setting

Objective

This study aims to explore the feasibility of HeartModel ^A.I. (HM) three-dimensional echocardiography (3DE) to assess left ventricular function and discover suitable border parameter settings.

Methods

A total of 113 patients that underwent echocardiography in our hospital were eligible for inclusion. The HM 3DE (HM method) and conventional 3DE (3D method) were used to analyze echocardiography images. The HM was set to different border settings (end-diastolic [ED] and end-systolic [ES] settings) to assess different left ventricular systolic function parameters including left ventricular end diastolic volume (LVEDV), left ventricular end systolic volume (LVESV), and left ventricular ejection fraction (LVEF), and left ventricular diastolic function parameters including maximal left atrium volume (LAV_MAX). All of these parameters were evaluated using the HM method and then compared with the 3D method.

Results

The differences in LVEDV, LVESV, and LVEF measured with different HM border settings were statistically significant (P<0.05) and were strongly correlated with the 3D method. For LVEF, the reading using the HM method with ED and ES = 70 and 30 showed the best agreement with the 3D method, and the difference in the readings was not statistically significant (P > 0.05). For LVEDV and LVESV, the reading using the HM method with ED and ES = 40 and 20 showed the best agreement with the 3D method, but the difference in the readings was statistically significant (P < 0.05). The measurements taken using the HM method were more reproducible than those taken using the 3D method (P<0.05). The measurement time when using the HM method was significantly less than the 3D method (P<0.05). In terms of LAV_MAX, the correlation between the HM and 3D methods was strong, but the requirements for agreement were not satisfied.

Conclusion

Evaluation of the left ventricular function using HM 3DE is feasible, saves time, and is reproducible. To assess the left ventricular function, the border parameter setting of ED and ES = 70 and 30 provided the best fit for the Chinese population.

British Society for Echocardiography and British Cardio-Oncology Society guideline for transthoracic echocardiographic assessment of adult cancer patients receiving anthracyclines and/or trastuzumab

The subspecialty of cardio-oncology aims to reduce cardiovascular morbidity and mortality in patients with cancer or following cancer treatment. Cancer therapy can lead to a variety of cardiovascular complications, including left ventricular systolic dysfunction, pericardial disease, and valvular heart disease. Echocardiography is a key diagnostic imaging tool in the diagnosis and surveillance for many of these complications. The baseline assessment and subsequent surveillance of patients undergoing treatment with anthracyclines and/or human epidermal growth factor (EGF) receptor (HER) 2-positive targeted treatment (e.g. trastuzumab and pertuzumab) form a significant proportion of cardio-oncology patients undergoing echocardiography. This guideline from the British Society of Echocardiography and British Cardio-Oncology Society outlines a protocol for baseline and surveillance echocardiography of patients undergoing treatment with anthracyclines and/or trastuzumab. The methodology for acquisition of images and the advantages and disadvantages of techniques are discussed. Echocardiographic definitions for considering cancer therapeutics-related cardiac dysfunction are also presented.

BSE and BCOS Guideline for Transthoracic Echocardiographic Assessment of Adult Cancer Patients Receiving Anthracyclines and/or Trastuzumab

The subspecialty of cardio-oncology aims to reduce cardiovascular morbidity and mortality in patients with cancer or following cancer treatment. Cancer therapy can lead to a variety of cardiovascular complications, including left ventricular systolic dysfunction, pericardial disease, and valvular heart disease. Echocardiography is a key diagnostic imaging tool in the diagnosis and surveillance for many of these complications. The baseline assessment and subsequent surveillance of patients undergoing treatment with anthracyclines and/or human epidermal growth factor receptor (HER) 2-positive targeted treatment (e.g., trastuzumab and pertuzumab) form a significant proportion of cardio-oncology patients undergoing echocardiography. This guideline from the British Society of Echocardiography and British Cardio-Oncology Society outlines a protocol for baseline and surveillance echocardiography of patients undergoing treatment with anthracyclines and/or trastuzumab. The methodology for acquisition of images and the advantages and disadvantages of techniques are discussed. Echocardiographic definitions for considering cancer therapeutics-related cardiac dysfunction are also presented.

Comparison Between 3D Echocardiography and Cardiac Magnetic Resonance Imaging (CMRI) in the Measurement of Left Ventricular Volumes and Ejection Fraction

BACKGROUND

Echocardiography and Cardiac Magnetic Resonance Imaging (CMRI) are two noninvasive techniques for the evaluation of cardiac function for patients with coronary artery diseases. Although echocardiography is the commonly used technique in clinical practice for the assessment of cardiac function, the measurement of LV volumes and left ventricular ejection fraction (LVEF) by the use of this technique is still influenced by several factors inherent to the protocol acquisition, which may affect the accuracy of echocardiography in the measurement of global LV parameters.

OBJECTIVE

The aim of this study is to compare the end systolic volume (ESV), the end diastolic volume (EDV), and the LVEF values obtained with three dimensional echocardiography (3D echo) with those obtained by CMRI (3 Tesla) in order to estimate the accuracy of 3D echo in the assessment of cardiac function.

METHODS

20 subjects, (9 controls, 6 with myocardial infarction, and 5 with myocarditis) with age varying from 18 to 58, underwent 3D echo and CMRI. LV volumes and LVEF were computed from CMRI using a stack of cine MRI images in a short axis view. The same parameters were calculated using the 3D echo. A linear regression analysis and Bland Altman diagrams were performed to evaluate the correlation and the degree of agreement between the measurements obtained by the two methods.

RESULTS

The obtained results show a strong correlation between the 3D echo and CMR in the measurement of functional parameters (r = 0.96 for LVEF values, r = 0.99 for ESV and r= 0.98 for EDV, p < 0.01 for all) with a little lower values of LV volumes and higher values of LVEF by 3D echo compared to CMRI. According to statistical analysis, there is a slight discrepancy between the measurements obtained by the two methods.

CONCLUSION

3D echo represents an accurate noninvasive tool for the assessment of cardiac function. However, other studies should be conducted on a larger population including some complicated diagnostic cases.

3-Dimensional Echocardiography and 2-D Strain Analysis of Left Ventricular, Left Atrial and Right Ventricular Function in Healthy Brazilian Volunteers

BACKGROUND

New echocardiographic techniques are used in the diagnosis and prognosis of many heart diseases. However, reference values in different populations are still needed for several of these new indexes. We studied these new echocardiographic parameters in a group of Brazilians with no known cardiovascular disease.

OBJECTIVE

To study values for new echocardiographic indexes in Brazilians without known cardiovascular disease and their correlation with age.

METHODS

Cross-sectional study that included healthy individuals who underwent three-dimensional echocardiography (3DE) and two-dimensional speckle tracking echocardiography (STE) strain (e) analysis. Left atrial (LA) and left ventricular (LV) function were analyzed by 3DE and STE, and right ventricular (RV) function by STE. P values < 0.05 were considered significant.

RESULTS

Seventy-seven subjects (46.7% men; 40.4 ± 10.4 years) were included. Maximum, minimum and pre-atrial contraction (pre-A) LA volumes (ml/m2) were 21.2 ± 5.5, 7.8 ± 2.5, and 11.0 ± 3.1, respectively. Peak positive global LA e (LAScd), peak negative global LA e and total global LA e (LASr) were 17.4 ± 5.2%, -13.2 ± 2.0% and 30.5 ± 5.9%, respectively. LV end-diastolic and end-systolic volumes (ml/m2) measured 57 ± 12 and 24 ± 6, and 3D LV ejection fraction measured 58 ± 6%. Global LV longitudinal, circumferential and radial e were -19 ± 2%, -19 ± 3%, and 46 ± 12%, respectively. LV torsion measured 1.6 ± 0.70 /cm. Global longitudinal RV e (RV-GLS) and RV free wall strain were -22 ± 3% and -24 ± 5%. Minimum LA and pre-A volumes, LV apical rotation, torsion and RV-GLS increased with age, while total and passive LA emptying fractions, LAScd, LASr, LV end-diastolic and end-systolic volumes decreased with age.

CONCLUSION

Values for new echocardiographic indexes in Brazilians without known cardiovascular disease and their correlation with age are presented.