Normal and shear strains of the left ventricle in healthy human subjects measured by two-dimensional speckle tracking echocardiography

Application of 4-D ultrasound-derived regional strain and proteomics analysis in Nkx2-5-deficient male mice

The comprehensive characterization of cardiac structure and function is critical to better understanding various murine models of cardiac disease. We demonstrate here a multimodal analysis approach using high-frequency four-dimensional ultrasound (4DUS) imaging and proteomics to explore the relationship between regional function and tissue composition in a murine model of metabolic cardiomyopathy (Nkx2-5183P/+). The presented 4DUS analysis outlines a novel approach to mapping both circumferential and longitudinal strain profiles through a standardized framework. We then demonstrate how this approach allows for spatiotemporal comparisons of cardiac function and improved localization of regional left ventricular dysfunction. Guided by observed trends in regional dysfunction, our targeted Ingenuity Pathway Analysis (IPA) results highlight metabolic dysregulation in the Nkx2-5183P/+ model, including altered mitochondrial function and energy metabolism (i.e., oxidative phosphorylation and fatty acid/lipid handling). Finally, we present a combined 4DUS-proteomics z-score-based analysis that highlights IPA canonical pathways showing strong linear relationships with 4DUS biomarkers of regional cardiac dysfunction. The presented multimodal analysis methods aim to help future studies more comprehensively assess regional structure-function relationships in other preclinical models of cardiomyopathy.NEW & NOTEWORTHY A multimodal approach using both four-dimensional ultrasound (4DUS) and regional proteomics can help enhance our investigations of murine cardiomyopathy models. We present unique 4DUS-derived strain maps that provide a framework for both cross-sectional and longitudinal analysis of spatiotemporal cardiac function. We further detail and demonstrate an innovative 4DUS-proteomics z-score-based linear regression method, aimed at characterizing relationships between regional cardiac dysfunction and underlying mechanisms of disease.

Clinical characterization, cardiovascular risk factor profile and cardiac strain analysis in a Uganda cancer population: The SATRACD study

BACKGROUND

The link between cancer and cardiovascular disease is firmly established. We sought to investigate the prevalence of cardiovascular disease (CVD) risk factors in Uganda cancer patients, their pre-chemotherapy left ventricular strain echocardiographic pattern and its associations with the CVD risk factors.

METHODS AND RESULTS

Baseline pre-chemotherapy data of patients who were enrolled in the SATRACD study (a cancer cohort, who were planned for anthracycline therapy), were analyzed. The prevalence of cardiovascular risk factors and baseline strain echocardiographic images were assessed. Among the 355 patients who were recruited over a period of 15 months, 283 (79.7%) were female, with a mean age of 43 years. The types of cancer of the study patients included breast cancer (70.6%), lymphomas, sarcomas, leukemias and hepatocellular carcinoma. Hypertension was the most common comorbidity (27.0%). The prevalence of obesity was 12.1% and that of HIV was 18.3%. All patients had a normal left ventricular ejection fraction (LVEF). The mean global longitudinal strain (GLS) was -20.92 ±2.43%, with females having a significantly higher GLS than males (-21.09±2.42 vs -20.25±2.39, p = 0.008). Fifty-three patients (14.9%) had suboptimal GLS (absolute GLS≤18.00%), which was associated with obesity (POR = 3.07; 95% CI, 1.31-6.98; p = 0.003), alcohol use (POR = 1.94; 95% CI, 1.01-3.74; p = 0.044), long QTc interval in electrocardiogram (POR = 2.54; 95% CI, 1.06-5.74; p = 0.015,) and impaired left ventricular relaxation (POR = 2.24; 95% CI, 1.17-4.25; p = 0.007). On multivariable logistic regression analysis, obesity (POR = 2.95; 95% CI, 1.24-7.03; p = 0.014) was the only independent factor associated with suboptimal GLS.

CONCLUSION

There is high prevalence and a unique pattern of cardiovascular risk factors in Uganda cancer patients. In cancer patients with cardiovascular risk conditions, there is reduction in GLS despite preserved LVEF. Longitudinal research is needed to study the predictive value of cardiovascular risk factors and baseline GLS for post chemotherapy cardiac dysfunction.

How His bundle pacing prevents and reverses heart failure induced by right ventricular pacing

Ideal heart performance demands vigorous systolic contractions and rapid diastolic relaxation. These sequential events are precisely timed and interdependent and require the rapid synchronous electrical stimulation provided by the His-Purkinje system. Right ventricular (RV) pacing creates slow asynchronous electrical stimulation that disrupts the timing of the cardiac cycle and results in left ventricular (LV) mechanical asynchrony. Long-term mechanical asynchrony produces LV dysfunction, remodeling, and clinical heart failure. His bundle pacing preserves synchronous electrical and mechanical LV function, prevents or reverses RV pacemaker-induced remodeling, and reduces heart failure.

Practical tips and tricks in measuring strain, strain rate and twist for the left and right ventricles

Strain imaging provides an accessible, feasible and non-invasive technique to assess cardiac mechanics. Speckle tracking echocardiography (STE) is the primary modality with the utility for detection of subclinical ventricular dysfunction. Investigation and adoption of this technique has increased significantly in both the research and clinical environment. It is therefore important to provide information to guide the sonographer on the production of valid and reproducible data. The focus of this review is to (1) describe cardiac physiology and mechanics relevant to strain imaging, (2) discuss the concepts of strain imaging and STE and (3) provide a practical guide for the investigation and interpretation of cardiac mechanics using STE.

Ultrasonic image analysis of longitudinal strain in uremic patients with preserved left ventricular ejection fraction

Background

Patients with uremia have high cardiovascular disease morbidity and mortality despite having normal left ventricular ejection fraction (LVEF). Longitudinal strain (LS) can be associated with subtle changes in LV systolic function. The aim of this study was to use two-dimensional speckle-tracking echocardiography (2DSTE) to assess subclinical LV myocardial dysfunction and to explore strain-changing regularities in uremic patients with LVEF ≥ 55%.

Methods

The study population included 40 uremic patients and 40 healthy volunteers. 2DSTE was performed on all participants to assess peak LS in the basal, mid and apical LV (BLS, MLS and ALS) and the respective time to peak LS (T-BLS, T-MLS, T-ALS).

Results

BLS, MLS, and ALS were significantly decreased in the uremic group relative to healthy controls and LS increased going in a basal to apical direction in both groups. T-BLS, T-MLS and T-ALS was significantly increased in the uremic group compared with the control group. In uremic patients, T-BLS, but not T-MLS or T-ALS, was significantly delayed relative to the control group. Bivariate analysis of creatinine (Cr) or urea nitrogen and strain parameters revealed a correlation only between ALS and Cr.

Conclusion

2DSTE can identify LV myocardial abnormalities in uremic patients with preserved LVEF at early stage, as well as some changing regularities of LS and T-LS in the left ventricle.

Adult echocardiographic nomograms: overview, critical review and creation of a software for automatic, fast and easy calculation of normal values

There is a crescent interest on normal adult echocardiographic values and the introduction of new deformation imaging and 3D parameters pose the issue of normative data. A multitude of nomograms has been recently published, however data are often fragmentary, difficult to find, and their strengths/limitations have been never evaluated.

AIMS

(I) to provide a review of current echocardiographic nomograms; (II) to generate a tool for easy and fast access to these data. A literature search was conducted accessing the National Library of Medicine using the keywords: 2D/3D echocardiography, strain, left/right ventricle, atrial, mitral/tricuspid valve, aorta, reference values/nomograms/normal values. Adding the following keywords, the results were further refined: range/intervals, myocardial velocity, strain rate and speckle tracking. Forty one published studies were included. Our study reveals that for several of 2D/3D parameters sufficient normative data exist, however, a few limitations still persist. For some basic parameters (i.e., mitral/tricuspid/pulmonary valves, great vessels) and for 3D valves data are scarce. There is a lack of studies evaluating ethnic differences. Data have been generally expressed as mean values normalised for gender and age instead of computing models incorporating different variables (age/gender/body sizes) to calculate z scores. To summarize results a software (Echocardio-Normal Values) who automatically calculate range of normality for a broad range of echocardiographic measurements according to age/gender/weight/height, has been generated. We provide an up-to-date and critical review of strengths/limitation of current adult echocardiographic nomograms. Furthermore we generated a software for automatic, easy and fast access to multiple echocardiographic normative data.