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Featured researches published by D. Leong.


Jacc-cardiovascular Imaging | 2010

MR Imaging and Cardiac Amyloidosis: Where to Go From Here?⁎

Joseph B. Selvanayagam; D. Leong

Cardiac amyloidosis describes clinically significant involvement of the heart by amyloid deposition, which may or may not be associated with involvement of other organs. Acquired systemic amyloidosis occurs in more than 10 per million person-years in the U.S. population, and cardiac involvement


Journal of Cardiovascular Magnetic Resonance | 2012

Early cardiac changes following anthracycline chemotherapy in breast cancer: a prospective multi-centre study using advanced cardiac imaging and biochemical markers

Suchi Grover; Carmine DePasquale; D. Leong; Adhiraj Chakrabarty; Kerry A Cheong; Dusan Kotasek; Rohit Joshi; A. Penhall; M. Joseph; Bogda Koczwara; Joseph B. Selvanayagam

Summary This prospective study is designed to identify novel ima- ging (utilizing cardiovascular magnetic resonance and advance echocardiography) and biochemical markers to detect early, sub-clinical cardiotoxicity following chemotherapy. Background Cardiac toxicity is an important long term side effect of anthracyline chemotherapy. We hypothesized that novel cardiovascular magnetic resonance (CMR) and echocar- diographic markers of myocardial function, oedema, and necrosis can detect early, subclinical cardiac toxicity in patients receiving anthracycline therapy for breast cancer. recovery fast-spin echo sequence (short-TI inversion recovery) was used in 3 short-axis views of the left ven- tricle. For assessment of myocardial oedema, the ratio of mean signal intensity (SI) of the myocardium was com- pared to that of skeletal muscle. Results In the study patients, the mean CMR LV end-systolic volume index (LVESVI) increased from baseline of 17.8 ± 6.2 to 20.3 ± 5.9 mL/m2 (p 1.9 as specified by Lake Louis criteria) in one or more short axis slices post chemotherapy. There was no new late gadolinium hyperenhancement to suggest focal myocar- dial necrosis/fibrosis in any patient following therapy.


Journal of Cardiovascular Magnetic Resonance | 2013

Early and late left ventricular effects of breast cancer chemotherapy: a prospective multi-centre study using advanced cardiac imaging

Suchi Grover; Carmine DePasquale; Govindarajan Srinivasan; D. Leong; Adhiraj Chakrabarty; Kerry A Cheong; Rohit Joshi; A. Penhall; M. Joseph; Bogda Koczwara; Joseph B. Selvanayagam

Background Myocardial dysfunction is a recognized toxicity of anthracycline (A) and herceptin (H) chemotherapy. Whilst there is much current focus on the incidence and magnitude of myocardial dysfunction following the A/H regimen, whether these changes are mediated by reversible or irreversible myocardial injury remains unknown. We sought to determine rates of persistent LV dysfunction at 12 months (as defined by left ventricular ejection fraction (LVEF) decrease by 10% or below lower limits of normal) following A/H and explore the mechanism of myocardial dysfunction using advance cardiac imaging.


Journal of Cardiovascular Magnetic Resonance | 2015

Comparison of GLS via echocardiography and tissue tracking by Cardiac Magnetic Resonance imaging

John-Paul Tantiongco; Suchi Grover; Rebecca Perry; Craig Bradbrook; D. Leong; Joseph B. Selvanayagam

Background Global longitudinal strain (GLS), has shown utility in detecting early subclinical LV dysfunction and has demonstrated significant efficacy in evaluating patients for chemotherapy cardiotoxicity. However, echocardiography is often reliant on operator experience and adequate quality windows for assessment. CMR is not subject to limitations of poor image quality due to its superior endocardial definition. We evaluated CMR derived strain by implementing a tissue tracking algorithm and compared it to GLS by 2D echocardiography in a prospective study of chemotherapy patients.


Journal of Cardiovascular Magnetic Resonance | 2013

Contemporary breast cancer chemotherapy leads to persistent late right ventricular myocardial dysfunction: a prospective multi-centre study

Suchi Grover; Carmine DePasquale; Govindarajan Srinivasan; D. Leong; Adhiraj Chakrabarty; Kerry A Cheong; Rohit Joshi; A. Penhall; M. Joseph; Bogda Koczwara; Joseph B. Selvanayagam

Background Previous studies evaluating cardiac effects of chemotherapy have focussed on the left ventricle (LV) and largely been retrospective. Although right ventricle (RV) systolic dysfunction is an adverse prognostic marker in cardiomyopathy states, the RV effects of chemotherapy are not well defined. Methods


Journal of Cardiovascular Magnetic Resonance | 2014

Reduced myocardial perfusion in post renal transplant population is not associated with aortic stiffness

S. Parnham; Suchi Grover; Craig Bradbrook; D. Leong; Carmine G. De Pasquale; Jonathan M. Gleadle; Joseph B. Selvanayagam

Background Objective: The purpose of this study was to assess central (aortic) vascular dysfunction in post renal transplant patients by high-resolution cardiovascular magnetic resonance imaging (CMR). Background: Renal transplant recipients are at increased risk of cardiovascular (CV) disease. The cardiac phenotype in post-transplant recipients is not well defined. A recent study suggested myocardial perfusion is impaired in renal transplant patients irrespective of the degree of left ventricular hypertrophy [1].We hypothesized that post transplant patients have persistently increased aortic stiffness, and that it could be correlated with reduced myocardial perfusion.


Journal of Cardiovascular Magnetic Resonance | 2014

Myocardial oxygenation is reduced in end-stage renal failure: a novel blood oxygen level dependant (BOLD)-cardiac MRI study

S. Parnham; Suchi Grover; Craig Bradbrook; D. Leong; Carmine G. De Pasquale; Jonathan M. Gleadle; Joseph B. Selvanayagam

Background Cardiovascular disease is the leading cause of mortality and morbidity in end-stage renal failure (ESRF) population, mostly from coronary artery disease (CAD). Majority of CAD in ESRF patients is asymptomatic and current cardiac stress imaging modalities are sub-optimal as risk predictors. Advances in cardiovascular magnetic resonance (CMR) with the novel blood oxygen level-dependent (BOLD) technique provides unprecedented capability to assess regional myocardial deoxygenation. We hypothesized that myocardial oxygenation would be reduced in ESRF patients and may form a novel strategy to assess myocardial ischemia. Methods Sixteen chronic renal failure (CRF) patients (7 on dialysis, 9 pre-dialysis) with no known history of CAD underwent CMR scanning at 3.0 T. Given known reductions in BOLD signals in hypertrophied myocardium, we also assessed a control group of HT patients with no history of CAD (n = 6) Myocardial function, rest and stress BOLD was performed. To measure oxygenation, using a T2-prepared BOLD sequence, myocardial Signal Intensity (SI) was measured at adenosine stress (140 μg/ kg/min) and at rest (corrected to RR interval). Comparison of myocardial SI analyses were performed using multivariate linear regression. Results


Journal of Cardiovascular Magnetic Resonance | 2012

Correlation of cardiac magnetic resonance imaging and biochemical markers of myocardial injury in a multi-centre study: PROTECTION AMI CMR substudy

Suchi Grover; G. Bell; Christine M Edwards; Saling Huang; D. Leong; Per Lav Madsen; Cameron Bridgman; Sean K Leow; Adhiraj Chakrabarty; Joseph B. Selvanayagam

The purpose of this study was to determine predictors of 90-day left ventricular function following acute ST-segment elevation myocardial infarction (STEMI) using variables from clinical presentation, biomarker testing, and cardiovascular magnetic resonance imaging (CMR).


Journal of Cardiovascular Magnetic Resonance | 2011

Validation of echocardiographic indices of right ventriclular systolic function with cardiac magnetic resonance: a comparative study

Suchi Grover; D. Leong; Payman Molaee; Mitra Shirazi; Adhiraj Chakrabarty; A. Penhall; Rebecca Perry; M. Joseph; Joseph B. Selvanayagam

Right ventricular ejection fraction (RVEF) is an important predictor of outcome in heart failure patients. Although cardiac magnetic resonance (CMR) assessment of RV function is considered gold standard and echocardiographic measurement of RVEF is challenging due to its unique geometry; CMR still has limited availability in the wider community. Therefore alternative echocardiographic indices such as tricuspid annular plane systolic excursion (TAPSE), peak tricuspid annular systolic velocity (RV S’) and RV fractional area change (RV FAC) have been evaluated and demonstrated prognostic value, however, comparison studies with RVEF by CMR are limited.


Journal of Nuclear Cardiology | 2011

Evaluation of left ventricular function using cardiac magnetic resonance imaging

Suchi Grover; D. Leong; Joseph B. Selvanayagam

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Suchi Grover

Flinders Medical Centre

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A. Penhall

Flinders Medical Centre

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M. Joseph

Flinders Medical Centre

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