Pūtahi Manawa Research Fellow Dr Debbie Zhao harnesses technology to close the equity gap

In 2023, Dr Debbie Zhao, a research fellow from Auckland Bioengineering Institute was awarded a Pūtahi Manawa Fellowship award for her project “Redefining references ranges for heart health in Aotearoa”. These fellowships are awarded based on the Pūtahi Manawa funding principles of Equity, Te Tiriti o Waitangi, Scientific Integrity, Co-design and Translation. Our Research Engagement Manager, Lisa Wong, sat down with Debbie to chat about her research

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Thanks Debbie for taking the time today. It’s rare we get a chance to sit down to talk about your research – normally we are interacting over outreach events! Can you start off by telling me about your research interests?

Sure! Great to be here. My area of research is in integrating biphysical modelling and AI [artificial intelligence] to make cardiac imaging more efficient, accurate and accessible. Specifically, I look at MRI [magnetic resonance imaging] and echocardiography [echo], which is really interesting because they are two very different imaging techniques. Echo is an ultrasound tehcnique which has great accessibility and is widely used. On the other hand, MRI is an advanced modality with limited access, but can provide very detailed visualisations of the heart. In Aoteaora, we have a strong history of being pioneers in cardiac space. It’s great to be able to continue this tradition of innovation and research to improve heart health.

Tell me more about your current project.

During my PhD, I ran a study with over 150 participants between the ages of 18 and 80, which included both healthy volunteers and patients with cardiac disease. They were scanned with both 3D echocardigraphy (echo) and MRI in order to build a comprehensive "map" that can be used to translate between the two modalities, so that in the future, one could just do an ultrasound but get the same information as an MRI. This could really impact patient care and access as MRI is only available in large centres and is very expensive. There is a huge geographic disparity—you may be okay in Auckland, but not everyone else would get same standard of care. My current research focuses on the clinical translation of this research and how we can help to reduce the cardiac imaging waitlist (which is up to 22 months in public system).

When you take a cardiac image, a clinician will analyse this and make some measurements.  Based on these measurements, they will make a diagnosis and decide on the most suitable treatment. With clinical decision making, these decisions are based on reference ranges which define “normal” and “abnormal”, or healthy and unhealthy. Unfortunately, many of these guidelines are based on large population studies overseas, such as the UK Biobank (consisting of a predominantly Caucasian population). These ranges work great for that demographic, but not so great when applied to our population here in Aotearoa. More specifically, it's well known that these reference ranges adversely bias the outcomes for Māori and Pacific.

How so?

These measures are indexed against body mass, which we know is not a valid measure for Māori and Pacific Peoples. So in order for one of these patients to qualify for certain treatments, they essentially have to be "more sick" to cross the threshold. Unfortunately, this is part of the current clinical practice, which we know is having an inequitable impact on these patients. One of my clinical collaborators, cardiologist Dr Boris Lowe, decided it was time to define new reference ranges that are specific to Aotearoa. So we teamed up and I applied for a Pūtahi Manawa Fellowship! It’s an incredible transdiscplinary collaboration. Alongside us in our mission are Misty Edmonds and Mardi Heath who provide Māori and Pacific nursing and cultural expertise, Anna Lydon, the charge MR Technologist at the Centre for Advanced MRI, and Martyn Nash, Professor at the Auckland Bioengineering Institute.

We are planning a new study which involves recruiting 300 healthy Māori and Pacific volunteers across all ages. Not only can we define new reference ranges for basic measurements used in everyday clinical decision making, we can go a step further and derive more sophisticated biophysical models. These could be important for better understanding the mechanisms of heart disease in different populations.

How did you end up in research?

(Laughs) Accidentally! Growing up, I always wanted to be a medical doctor. I owe my path to a high school physics teacher, Mr Fry, who told me about biomedical engineering. I enjoyed math and physics, but I also had a passion for anatomy and physiology, so this seemed like a good way to combine both. My initial idea at the time was to do engineering first, followed by medicine (so I could build my own devices and use them in my practice). As part of my engineering degree requirements, I had the opportunity to do a summer resarch project which I thoroughly enjoyed. It just happened that Professor Martyn Nash, who was one of my supervisors at the time, had a PhD project on offer that was very clincially orientated, which I happily accepted. It meant that I still got to interact with patients and clinicians, but also apply my engineering skills. It was a perfect match! In the end, I became a different type of "doctor", but I’m really happy with where I am. This is my dream job now!

That’s so cool! So much is about having the right mentors with the right support at the right time who are there to nurture your skills and interests. We all know that research can be pretty challenging sometimes. What lights your fire/ahi? What keeps you motivated?

It’s the person to person interactions and knowledge sharing. A lot of research is done behind a computer screen or in a lab, but there are always oppportunities to do outreach and interact with the public. I love going to schools and explaining (sometimes quite complicated) concepts to children and adults of all ages and seeing their eyes light up. I love talking with patients and listening to their stories. It makes me feel that my research has real world impact.

Where do you see yourself in 10 years?

Still in research? (laughs) One thing I realise is that there is so much to do!  An infinite amount of research. One question leads to ten. I will still be asking questions!


What do you think are the greatest challenges you’ve faced as a researcher?

I've been really lucky that the people I work with are all really supportive. I can't actually think of specific one thing. You need to have passion and perseverence because research is never easy. There is never a clear answer and you have to be able to accept that there probably won't be an easy or perfect solution, but research will help you to get closer to it.

One of the hardest things I’ve encountered (because my research involves working closely with patients) is the state of inequity in heart health. It can be really heartbreaking, especially when patients tell you their own stories, and you start to realise their individual stories are not just one story—it is the story of many. While it's not a "research challenge" per se, it’s nevertheless difficult, and definitely a strong a motivator for me. It’s empowering to be able to do the research to make a difference. It’s why I've applied for this fellowship from Pūtahi Manawa to do this project. At end of the day, we can use the most advanced techniques in the world to make cardiac imaging better and faster, but if the guidelines are wrong in the first place, that won't help anyone. The change has to be at a fundamental level.


What advice would you give to others, especially those starting on their research journey?

Don't be afraid to talk to others. A common trap is that you become an expert in one small field (which is sort of what research is about), but don't forget that your very small field links to a very big world. Don't be afraid to talk to other people outside of your immediate sphere. Talk to patients, clinicians, other researchers, engineers, etc. It's easy to lose sight of the big picture because you can get absorbed in answering a very specific question. There are a lot of ways that research can be rewarding. It’s not just about your paper or grant application getting accepted. You are a researcher, but you're also a person, and part of a community—so always remember to pay attention to those around you.

Thanks Debbie for this. We can’t wait to see where this research goes next. Best of luck!