Research Projects
Cardiac Imaging of Asymptomatic Type 2 Diabetics with Cardiovascular High Risk to measure Empagliflozin impact on Myocardial Blood Flow (CATCH-EM)


Programme(s) to which this project applies:

☑ MPhil/PhD ☒ MRes[Med] ☑ URIS
About the Project

Cardiovascular disease remains the most common cause of death in patients with type 2 diabetes(1). Asymptomatic coronary artery disease (CAD) is highly prevalent (ie. 17-59%) in patients with type 2 diabetes(2, 3). The lack of symptoms in patients with diabetes delays patient presentation and increases the risk of adverse events. Screening trials have thus been conducted to help reduce cardiovascular complications in asymptomatic patients with type 2 diabetes. However, imaging based screening trials of asymptomatic type 2 diabetic patients, using coronary computed tomography angiograms (CCTA) or nuclear myocardial perfusion imaging (MPI), have been unsuccessful at reducing cardiovascular death and all cause mortality when compared to optimised medical therapy for cardiovascular risk factors (4, 5). Two possible explanations for the failure could be i) the treatment target along with therapeutic options and ii) the choice of imaging modality to identify the treatment targets.

 

Microvascular Coronary Artery Disease (MCAD)

Screening trials in asymptomatic diabetics have tended to focus on treating epicardial coronary artery disease only and using coronary stenting for treatment. However, MCAD is highly prevalent amongst type 2 diabetic patients, and its prognostic and pathological importance are increasingly recognised(6). A large study by Murthy et al, demonstrated MCAD to be an independent risk factor for major adverse cardiovascular events (MACE)(7). This study further showed that diabetic patients without obstructive CAD but reduced coronary flow reserve (a measure of MCAD) had similar outcomes to non-diabetic patients with obstructive CAD(7). Therefore, a screening programme could be more successful if i) the imaging modality can identify MCAD in addition to obstructive CAD and ii) there are therapies to treat both obstructive CAD and/ or MCAD. Currently, there is a knowledge gap on effective therapies for halting progression or reversing MCAD.

 

Research Question

It is unknown whether empagliflozin will improve myocardial blood flow and resolve myocardial ischaemia caused by microvascular coronary artery disease (MCAD) in asymptomatic patients with type 2 diabetes. We propose to perform a double blinded randomised controlled trial to compare placebo with optimised medical therapy against empagliflozin in addition to optimised medical therapy to improve myocardial blood flow as measured by stress CMR. This trial would provide evidence if 10mg of empagliflozin given for 6 months could be an indicated treatment in asymptomatic high risk type 2 diabetic patients using stress CMR. The duration of 6 months is slightly longer than the mouse study (ie. 5 months) which showed an improvement in myocardial blood flow but not too long that the risk of increased patient withdrawal from the study will occur.

 

Aims

  1. To conduct a randomised controlled trial of empagliflozin and determine if empagliflozin will improve myocardial blood flow in asymptomatic high risk type 2 diabetic patients.
  2. Determine a cut-off using maximum upslope ratio and myocardial perfusion reserve index in which patients would demonstrate an improvement in myocardial blood flow.
  3. Assess novel cardiac CT parameters to assess change in atherosclerotic plaque and myocardial mass to determine the effect of empagliflozin.
About the Supervisor

Dr MY Ng, Department of Diagnostic Radiology

Dr Ming-Yen Ng, BMedSci(UK), BMBS (UK), FRCR(UK), FSCMR, FACC is a Clinical Assistant Professor in the Department of Diagnostic Radiology, The University of Hong Kong. He is the division Chief of Cardiac Imaging at the HKU– Shenzhen Hospital, China.

Dr Ng completed his medical and radiology training in the UK and sub-specialised in cardiothoracic imaging. He subsequently undertook a 1 year cardiac CT and cardiac MR fellowship in Toronto General Hospital, Canada.

Dr Ng is a fellow of the Society of Cardiovascular Magnetic Resonance and serves as the vice-chair of the education committee. He also has level 3 accreditation from the Society of Cardiovascular Computed Tomography and sits on its corporate relations committee. He is the course director of the highly successful cardiac MRI and CT Massive Open Online Courses produced by HKU.

He set up the cardiac MRI units in the University of Hong Kong and HKU-Shenzhen Hospital. He has obtained >HK$20million in funding for cardiac imaging projects and has published cardiothoracic imaging papers in journals such as JACC Cardiovascular Imaging, Circulation Cardiovascular Imaging, European Heart Journal Cardiovascular Imaging and Radiology.

Students who have worked in his unit have published in multiple journals including high impact journals. Dr Ng is keen to develop students to in their medical and research knowledge. Students will also be given privileged access to the MOOC on cardiac CT and MRI.

Biography
myng2@hku.hk

Next Step?

For more information or to express interest for this project, please email the supervisor or the specified contact point in the project description.  Interested candidates are advised to enclose with your email:

  1. your CV,
  2. a brief description of your research interest and experience, and
  3. two reference letters (not required for HKUMed UG students seeking MRes[Med]/URIS projects).

Information on the research programme, funding support and admission documentations could be referenced online at the Research Postgraduate Admissions website.

General admission enquiries should be directed to rpgmed@hku.hk.