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Background: Normal values for three-dimensional (3D) right ventricular (RV) size and function are not well established, as they originate from small studies that involved predominantly white North American and European populations, did not use RV-focused views, and relied on older 3D RV analysis software. The World Alliance Societies of Echocardiography study was designed to generate reference ranges for normal subjects around the world. The aim of this study was to assess the worldwide capability of 3D imaging of the right ventricle and report size and function measurements, including their dependency on age, sex, and ethnicity. Methods: Healthy subjects free of cardiac, pulmonary, and renal disease were prospectively enrolled at 19 centers in 15 countries, representing six continents. Three-dimensional wide-angle RV data sets were obtained and analyzed using dedicated RV software (TomTec) to measure end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume, and ejection fraction (EF). Results were categorized by sex, age (18-40, 41-65, and >65 years) and ethnicity. Results: Of the 2,007 subjects with attempted 3D RV acquisitions, 1,051 had adequate image quality for confident measurements. Upper and lower limits for body surface area-indexed EDV, ESV, and EF were 48 and 95 mL/m2, 19 and 43 mL/m2, and 44% and 58%, respectively, for men and 42 and 81 mL/m2, 16 and 36 mL/m2, and 46% and 61%, respectively, for women. Men had significantly larger EDVs, ESVs, and stroke volumes (even after body surface area indexing) and lower EFs than women (P < .05). EDV and ESV did not show any meaningful differences among age groups. Three-dimensional RV volumes were smallest in Asians. Conclusions: Reliability of 3D RV acquisition is low worldwide, underscoring the importance of future improvements in imaging techniques. Sex and race must be taken into consideration in the assessment of both RV volumes and EF.

Background: The echocardiographic investigation surrounding cardiac transplantation requires serial assessment of bi-ventricular function utilising twodimensional (2D) and Doppler assessment of cardiac size and function. To determine the suitability for transplantation and to detect changes in myocardial function post transplantation, echocardiography is used to detect complications such as acute cellular rejection (ACR). Detection of complications post cardiac transplantation using 2D and Doppler assessment of cardiac function has yielded conflicting results and is fraught with limitations which result in inconsistent findings unable to reliably detect meaningful changes associated with ACR. Left ventricular global longitudinal strain (LV GLS) has shown promising results in cross-sectional studies able to detect changes in myocardial strain between patients with ACR and those without, however the normal ranges for LV GLS in heart transplant patients displays a wide range of values without a common reference value to work from. Aims: The thesis aims to investigate the use of novel bi-ventricular strain parameters in the assessment of myocardial function surrounding cardiac transplantation. It is hypothesised that serial novel bi-ventricular strain parameters can detect myocardial abnormalities prior to biopsy confirmed ACR and alterations in myocardial abnormalities that better risk stratify patients both pre and post cardiac transplantation. [...], Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Medicine & Dentistry, Griffith Health, Full Text

Background: Accurate measurements of the aortic annulus and root are important for guiding therapeutic decisions regarding the need for aortic surgery. Current echocardiographic guidelines for identification of aortic root dilatation are limited because current normative values were derived predominantly from white individuals in narrow age ranges, and based partially on M-mode measurements. Using data from the World Alliance Societies of Echocardiography study, the authors sought to establish normal ranges of aortic dimensions across sexes, races, and a wide range of ages. Methods: Adult individuals free of heart, lung, and kidney disease were prospectively enrolled from 15 countries, with even distributions among sexes and age groups: young (18–40 years), middle aged (41–65 years) and old (>65 years). Transthoracic two-dimensional echocardiograms of 1,585 subjects (mean age, 47 ± 17 years; 50.4% men; mean body surface area [BSA], 1.77 ± 0.22 m2) were analyzed in a core laboratory following American Society of Echocardiography guidelines. Measurements, indexed separately by BSA and by height, included the aortic annulus, sinuses of Valsalva, and sinotubular junction. Differences among age, sex, and racial groups were evaluated using unpaired two-tailed Student's t tests. Results: All aortic root dimensions were larger in men compared with women. After indexing to BSA, all measured dimensions were significantly larger in women, whereas men continued to show larger dimensions after indexing to height. Of note, the upper limits of normal for all aortic dimensions were lower across all age groups, compared with the guidelines. Aortic dimensions were larger in older age groups in both sexes, a trend that persisted regardless of BSA or height adjustment. Last, differences in aortic dimensions were also observed according to race: Asians had the smallest nonindexed aortic dimensions at all levels. Conclusions: There are significant differences in aortic dimensions acco

Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School Allied Health Sciences, Griffith Health, Background. Left ventricular (LV) dysfunction, which is the inability of the LV to pump blood effectively, constitutes the final common pathway for a host of cardiac disorders. The morbidity, mortality and healthcare cost associated with heart failure make the detection and prevention an attractive option before irreversible myocardial damage occurs. Initial diagnosis of LV dysfunction is through echocardiography, which, predominately relies on two-dimensional ejection fraction (EF) however, is fraught with limitation. Global longitudinal strain (GLS) is an established method for subclinical diagnosis of heart disease, however, is sensitive to changes in afterload leading to misinterpretation of true contractile function. Myocardial work (MW) is a recent echocardiographic modality derived from non-invasive LV pressure-strain loops and addresses the afterload limitation of GLS. Aims. The thesis investigates the use of MW against conventional echocardiographic parameters in hypertensive heart disease, ischaemic and non-ischaemic cardiomyopathy and ischaemic heart disease. It is hypothesised that MW indices will be more sensitive than GLS and provide a new dimension in the clinical evaluation of LV dysfunction. Methods. Patients enrolled in the CATHARSIS research program performed at The Prince Charles Hospital who have comprehensive echocardiographic studies followed by invasive coronary angiography will be investigated. All echocardiographic measurements were performed in according to the current echocardiographic guidelines. GLS and MW analysis was calculated utilising speckle tracking echocardiography via vendor specific modules (EchoPAC Version 202, GE Vingmed Ultrasound, Norway). MW was derived from derived from non-invasive LV pressurestrain loops indexed to brachial systolic blood pressure. MW indices obtained include: Global myocardial work index (GWI) – a global representation of MW; Constructive MW (CW) – the sum of positive work due to myocardial shortening

Background. Left ventricular (LV) dysfunction, which is the inability of the LV to pump blood effectively, constitutes the final common pathway for a host of cardiac disorders. The morbidity, mortality and healthcare cost associated with heart failure make the detection and prevention an attractive option before irreversible myocardial damage occurs. Initial diagnosis of LV dysfunction is through echocardiography, which, predominately relies on two-dimensional ejection fraction (EF) however, is fraught with limitation. Global longitudinal strain (GLS) is an established method for subclinical diagnosis of heart disease, however, is sensitive to changes in afterload leading to misinterpretation of true contractile function. Myocardial work (MW) is a recent echocardiographic modality derived from non-invasive LV pressure-strain loops and addresses the afterload limitation of GLS. Aims. The thesis investigates the use of MW against conventional echocardiographic parameters in hypertensive heart disease, ischaemic and non-ischaemic cardiomyopathy and ischaemic heart disease. It is hypothesised that MW indices will be more sensitive than GLS and provide a new dimension in the clinical evaluation of LV dysfunction. Methods. Patients enrolled in the CATHARSIS research program performed at The Prince Charles Hospital who have comprehensive echocardiographic studies followed by invasive coronary angiography will be investigated. All echocardiographic measurements were performed in according to the current echocardiographic guidelines. GLS and MW analysis was calculated utilising speckle tracking echocardiography via vendor specific modules (EchoPAC Version 202, GE Vingmed Ultrasound, Norway). MW was derived from derived from non-invasive LV pressurestrain loops indexed to brachial systolic blood pressure. MW indices obtained include: Global myocardial work index (GWI) – a global representation of MW; Constructive MW (CW) – the sum of positive work due to myocardial shortening, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School Allied Health Sciences, Griffith Health, Full Text

Full Text, Thesis (Masters), Master of Philosophy (MPhil), School of Medicine, Griffith Health, The left atrium (LA) plays an important role in the modulation of LV filling and contributes to LV stroke volume with atrial contraction. Despite this important role, much research to date has been focused on the ventricles in disease, rather than the atria. In recent years there has been increasing interest and excitement in the function of the LA in normal and disease states – no longer is the LA secondary to the left ventricle (LV). The LA has three major functions: reservoir, conduit and contractile. The LA acts as a reservoir during ventricular systole as it fills with blood via the pulmonary veins and expands in size, subsequently, the mitral valve opens and the conduit phase is this passing of blood from the LA to the LV due to a small pressure gradient. Lastly, atrial systole, or the ‘atrial kick’, provides further augmentation of the LV stroke volume at the end of ventricular diastole. Methods for non-invasive assessment of these LA functions have been limited due to echocardiographic technology and the cumbersome nature data collection for these parameters. Prior techniques included assessment of LA size, phasic changes in LA size or volume as well as a variety of Doppler parameters which provided a cruder assessment of the LA functions. Strain is a unitless measurement of myocardial deformation and can be applied to assess the three LA functions in more detail. Contemporary strain research uses 2D-speckle tracking echocardiography (STE), where strain represents a fraction change in myocardial length relative to baseline and is expressed as a percentage. As strain technology surges forward with now dedicated LA strain software packages, the importance of the left atrium has become increasingly recognised. Improved strain technology has allowed easier and more widely available assessment of the three LA functions. Several studies have now documented normal LA strain values in large populations, and specifically, variations due to age and gender. Multiple li

The left atrium (LA) plays an important role in the modulation of LV filling and contributes to LV stroke volume with atrial contraction. Despite this important role, much research to date has been focused on the ventricles in disease, rather than the atria. In recent years there has been increasing interest and excitement in the function of the LA in normal and disease states – no longer is the LA secondary to the left ventricle (LV). The LA has three major functions: reservoir, conduit and contractile. The LA acts as a reservoir during ventricular systole as it fills with blood via the pulmonary veins and expands in size, subsequently, the mitral valve opens and the conduit phase is this passing of blood from the LA to the LV due to a small pressure gradient. Lastly, atrial systole, or the ‘atrial kick’, provides further augmentation of the LV stroke volume at the end of ventricular diastole. Methods for non-invasive assessment of these LA functions have been limited due to echocardiographic technology and the cumbersome nature data collection for these parameters. Prior techniques included assessment of LA size, phasic changes in LA size or volume as well as a variety of Doppler parameters which provided a cruder assessment of the LA functions. Strain is a unitless measurement of myocardial deformation and can be applied to assess the three LA functions in more detail. Contemporary strain research uses 2D-speckle tracking echocardiography (STE), where strain represents a fraction change in myocardial length relative to baseline and is expressed as a percentage. As strain technology surges forward with now dedicated LA strain software packages, the importance of the left atrium has become increasingly recognised. Improved strain technology has allowed easier and more widely available assessment of the three LA functions. Several studies have now documented normal LA strain values in large populations, and specifically, variations due to age and gender. Multiple li, Thesis (Masters), Master of Philosophy (MPhil), School of Medicine, Griffith Health, Full Text