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Open access

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

Christopher Johnson, Katherine Kuyt, David Oxborough, and Martin Stout

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.

Open access

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics: a study utilizing deformation volume analysis

Caroline Schneider, Lynsey Forsythe, John Somauroo, Keith George, and David Oxborough

Background

Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function; however, the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change.

Methods

A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume loops (deformation volume analysis – DVA).

Results

There was a leftward shift of the ε-volume loop from supine to 1 min and 5 min of HUT (P < 0.001). Moreover, longitudinal shortening was reduced (P < 0.001) with a concomitant increase in transverse thickening from supine to 1 min, which was further augmented at 5 min (P = 0.018).

Conclusions

Preload reduction occurs within 1 min of HUT but does not further reduce at 5 min. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations.

Open access

Reproducibility and feasibility of right ventricular strain and strain rate (SR) as determined by myocardial speckle tracking during high-intensity upright exercise: a comparison with tissue Doppler-derived strain and SR in healthy human hearts

Rachel N Lord, Keith George, Helen Jones, John Somauroo, and David Oxborough

This study aimed to establish feasibility for myocardial speckle tracking (MST) and intra-observer reliability of both MST and tissue velocity imaging (TVI)-derived right ventricular (RV) strain (ε) and strain rate (SR) at rest and during upright incremental exercise. RV ε and SR were derived using both techniques in 19 healthy male participants. MST-derived ε and SR were feasible at rest (85% of segments tracked appropriately). Feasibility reduced significantly with progressive exercise intensity (3% of segments tracking appropriately at 90% maximum heart rate (HRmax)). Coefficient of variations (CoVs) of global ε values at rest was acceptable for both TVI and MST (7–12%), with low bias and narrow limits of agreement. Global SR data were less reliable for MST compared with TVI as demonstrated with CoV data (systolic SR=15 and 61%, early diastolic SR=16 and 17% and late diastolic SR=26 and 31% respectively). CoVs of global RV ε and SR obtained at 50% HRmax were acceptable using both techniques. As exercise intensity increased to 70 and 90% HRmax, reliability of ε and SR values reduced with larger variability in MST. We conclude that RV global and regional ε and SR data are feasible, comparable and reliable at rest and at 50% HRmax using both MST and TVI. Reliability was reduced during higher exercise intensities with only TVI acceptable for clinical and scientific use.

Open access

Layer-specific systolic and diastolic strain in hypertensive patients with and without mild diastolic dysfunction

Hisham Sharif, Stephen Ting, Lynsey Forsythe, Gordon McGregor, Prithwish Banerjee, Deborah O’Leary, David Ditor, Keith George, Daniel Zehnder, and David Oxborough

This study sought to examine layer-specific longitudinal and circumferential systolic and diastolic strain, strain rate (SR) and diastolic time intervals in hypertensive patients with and without diastolic dysfunction. Fifty-eight treated hypertensive patients were assigned to normal diastolic function (NDF, N = 39) or mild diastolic dysfunction (DD, N = 19) group. Layer-specific systolic and diastolic longitudinal and circumferential strains and SR were assessed. Results showed no between-group difference in left ventricular mass index (DD: 92.1 ± 18.1 vs NDF: 88.4 ± 16.3; P = 0.44). Patients with DD had a proportional reduction in longitudinal strain across the myocardium (endocardial for DD −13 ± 4%; vs NDF −17 ± 3, P < 0.01; epicardial for DD −10 ± 3% vs NDF −13 ± 3%, P < 0.01; global for DD: −12 ± 3% vs NDF: −15 ± 3, P = 0.01), and longitudinal mechanical diastolic impairments as evidenced by reduced longitudinal strain rate of early diastole (DD 0.7 ± 0.2 L/s vs NDF 1.0 ± 0.3 L/s, P < 0.01) and absence of a transmural gradient in the duration of diastolic strain (DD endocardial: 547 ± 105 ms vs epicardial: 542 ± 113 ms, P = 0.24; NDF endocardial: 566 ± 86 ms vs epicardial: 553 ± 77 ms, P = 0.03). Patients with DD also demonstrate a longer duration of early circumferential diastolic strain (231 ± 71 ms vs 189 ± 58 ms, P = 0.02). In conclusion, hypertensive patients with mild DD demonstrate a proportional reduction in longitudinal strain across the myocardium, as well as longitudinal mechanical diastolic impairment, and prolonging duration of circumferential mechanical relaxation.

Open access

The assessment of mitral valve disease: a guideline from the British Society of Echocardiography

Shaun Robinson, Liam Ring, Daniel X Augustine, Sushma Rekhraj, David Oxborough, Allan Harkness, Patrizio Lancellotti, and Bushra Rana

Mitral valve disease is common. Mitral regurgitation is the second most frequent indication for valve surgery in Europe and despite the decline of rheumatic fever in Western societies, mitral stenosis of any aetiology is a regular finding in all echo departments. Mitral valve disease is, therefore, one of the most common pathologies encountered by echocardiographers, as both a primary indication for echocardiography and a secondary finding when investigating other cardiovascular disease processes. Transthoracic, transoesophageal and exercise stress echocardiography play a crucial role in the assessment of mitral valve disease and are essential to identifying the aetiology, mechanism and severity of disease, and for helping to determine the appropriate timing and method of intervention. This guideline from the British Society of Echocardiography (BSE) describes the assessment of mitral regurgitation and mitral stenosis, and replaces previous BSE guidelines that describe the echocardiographic assessment of mitral anatomy prior to mitral valve repair surgery and percutaneous mitral valvuloplasty. It provides a comprehensive description of the imaging techniques (and their limitations) employed in the assessment of mitral valve disease. It describes a step-wise approach to identifying: aetiology and mechanism, disease severity, reparability and secondary effects on chamber geometry, function and pressures. Advanced echocardiographic techniques are described for both transthoracic and transoesophageal modalities, including TOE and exercise testing.

Open access

Normal reference intervals for cardiac dimensions and function for use in echocardiographic practice: a guideline from the British Society of Echocardiography

Allan Harkness, Liam Ring, Daniel X Augustine, David Oxborough, Shaun Robinson, Vishal Sharma, and the Education Committee of the British Society of Echocardiography

This guideline presents reference limits for use in echocardiographic practice, updating previous guidance from the British Society of Echocardiography. The rationale for change is discussed, in addition to how the reference intervals were defined and the current limitations to their use. The importance of interpretation of echocardiographic parameters within the clinical context is explored, as is grading of abnormality. Each of the following echo parameters are discussed and updated in turn: left ventricular linear dimensions and LV mass; left ventricular volumes; left ventricular ejection fraction; left atrial size; right heart parameters; aortic dimensions; and tissue Doppler imaging. There are several important conceptual changes to the assessment of the heart’s structure and function within this guideline. New terminology for left ventricular function and left atrial size are introduced. The British Society of Echocardiography has advocated a new approach to the assessment of the aortic root, the right heart, and clarified the optimal methodology for assessment of LA size. The British Society of Echocardiography has emphasized a preference to use, where feasible, indexed measures over absolute values for any chamber size.

Open access

Normal reference intervals for cardiac dimensions and function for use in echocardiographic practice: a guideline from the British Society of Echocardiography

Allan Harkness, Liam Ring, Daniel X Augustine, David Oxborough, Shaun Robinson, Vishal Sharma, and the Education Committee of the British Society of Echocardiography

Open access

Response to Latest British Society of Echocardiography recommendations for left ventricular ejection fraction categorisation: potential implications and relevance to contemporary heart failure management

Allan Harkness, Liam Ring, Daniel X Augustine, David Oxborough, Shaun Robinson, Vishal Sharma, and the Education Committee of the British Society of Echocardiography

Open access

Echocardiographic assessment of the tricuspid and pulmonary valves: a practical guideline from the British Society of Echocardiography

Abbas Zaidi, David Oxborough, Daniel X Augustine, Radwa Bedair, Allan Harkness, Bushra Rana, Shaun Robinson, and Luigi P Badano

Transthoracic echocardiography is the first-line imaging modality in the assessment of right-sided valve disease. The principle objectives of the echocardiographic study are to determine the aetiology, mechanism and severity of valvular dysfunction, as well as consequences on right heart remodelling and estimations of pulmonary artery pressure. Echocardiographic data must be integrated with symptoms, to inform optimal timing and technique of interventions. The most common tricuspid valve abnormality is regurgitation secondary to annular dilatation in the context of atrial fibrillation or left-sided heart disease. Significant pulmonary valve disease is most commonly seen in congenital heart abnormalities. The aetiology and mechanism of tricuspid and pulmonary valve disease can usually be identified by 2D assessment of leaflet morphology and motion. Colour flow and spectral Doppler are required for assessment of severity, which must integrate data from multiple imaging planes and modalities. Transoesophageal echo is used when transthoracic data is incomplete, although the anterior position of the right heart means that transthoracic imaging is often superior. Three-dimensional echocardiography is a pivotal tool for accurate quantification of right ventricular volumes and regurgitant lesion severity, anatomical characterisation of valve morphology and remodelling pattern, and procedural guidance for catheter-based interventions. Exercise echocardiography may be used to elucidate symptom status and demonstrate functional reserve. Cardiac magnetic resonance and CT should be considered for complimentary data including right ventricular volume quantification, and precise cardiac and extracardiac anatomy. This British Society of Echocardiography guideline aims to give practical advice on the standardised acquisition and interpretation of echocardiographic data relating to the pulmonary and tricuspid valves.

Open access

Transthoracic echocardiography of hypertrophic cardiomyopathy in adults: a practical guideline from the British Society of Echocardiography

Lauren Turvey, Daniel X Augustine, Shaun Robinson, David Oxborough, Martin Stout, Nicola Smith, Allan Harkness, Lynne Williams, Richard P Steeds, and William Bradlow

Hypertrophic cardiomyopathy (HCM) is common, inherited and characterised by unexplained thickening of the myocardium. The British Society of Echocardiography (BSE) has recently published a minimum dataset for transthoracic echocardiography detailing the core views needed for a standard echocardiogram. For patients with confirmed or suspected HCM, additional views and measurements are necessary. This guideline, therefore, supplements the minimum dataset and describes a tailored, stepwise approach to the echocardiographic examination, and echocardiography’s position in the diagnostic pathway, before advising on the imaging of disease complications and invasive treatments.