Heart research pumping after $2.3m boost

Using phone videos to detect heart problems

Biomedical engineer Dr Prashanna Khwaounjoo is investigating whether smartphone videos of a person’s neck could help detect serious heart problems.

Khwaounjoo is trialling a non-invasive, smartphone-based heart diagnostic tool that captures tiny movements in the skin of the neck caused by blood flow. An algorithm then analyses these movements to assess the pulse signal.

“Our algorithm can track skin movement down to the micron level – movements you can’t really see with the eye. Instead of guesswork, we’re using a smartphone camera to record the movement and an algorithm to track it,” he says.

Khwaounjoo received a fellowship and a grant of $139,300 from the Heart Foundation to develop the tool.

It could offer a fast, low-cost way to help clinicians identify which patients should be referred for a full heart scan, he says.

“For patients, this may mean fewer unexpected hospital visits, clearer information about their heart health and more timely access to care,” says Khwaounjoo.

Creating a world-first sheep to boost heart research

The first ever sheep model of postmenopausal heart failure is being developed by the University of Auckland.

Dr Julia Shanks received $20,000 from the Heart Foundation to develop a sheep model, which she hopes will pave the way for new treatments for heart problems that can affect women after menopause.

In New Zealand, more than 40,000 people a year suffer heart failure with preserved ejection fraction (HFpEF), where the heart muscle becomes too stiff to function properly, says Shanks. HFpEF is the most common type of heart failure globally.

“Older women are at higher risk of this type of heart failure.

“They have often been misdiagnosed, because historically medical professionals might not have expected heart disease in women.

“And there are few effective therapies for this this type of heart failure, because it’s poorly understood,” she says.

Developing a sheep model of postmenopausal hypertensive heart failure with preserved ejection fraction could be the first step to turning this around, says Shanks, who is a senior research fellow in physiology at Manaaki Manawa, the Centre for Heart Research.

“There’s a critical lack of research on the way hormonal changes during menopause affect hypertension.

“As far as we’re aware, this will be a world-first sheep model that will help show the hormonal factors driving the development of heart disease in postmenopausal women.

“This will give us a foundation for future research and could help pave the way for more effective treatments,” she says.

Symptoms of HFpEF include severe breathlessness and fatigue. About half of people with the disease die within five years of diagnosis.

“It’s a difficult disease to live with and has a high mortality rate, so we’re doing everything we can to learn more about it and try to find ways to combat it,” says Shanks.

• All animal work done at Waipapa Taumata Rau, University of Auckland is approved by the University’s Animal Ethics Committee. Information on animal-based research at the University can be found here.
  

Could a pill replace a pacemaker?

Developing a drug alternative to pacemakers for people living with heart failure is the goal of senior research fellow Xin Shen.

Natural sensors in heart cells – called PIEZO1 – could one day help doctors treat heart failure with medicine instead of a pacemaker, says Shen, who received $227,927 from the Heart Foundation for his research.

“In heart failure, these sensors seem to stop working properly.

“This causes a cascade of effects that make it harder for the heart to pump effectively,” he says.

Shen is investigating whether these faulty signals could be corrected through a pill or other form of medicine.

"A medicine based on this pathway could be safer, easier to deliver, cheaper and more widely accessible than pacemakers," he says.

Previous research Shen contributed to discovered that the heart's structure and function could be restored towards a healthy state.

“I hope this project will one day lead to treatments that might reverse heart failure by helping repair and re-energise the heart,” he says.

Improving tests for genetic heart conditions

Dr Zoe Ward is investigating new ways to detect the genetic causes of inherited heart disease.

“Inherited heart conditions run in families and can cause serious problems, which can affect the heart muscle and cause irregular heart rhythms or even sudden death,” says Ward.

“They often affect people at a young age, with devastating effects for families.”

Often, people are unaware they are at risk of heart problems until something serious happens, she says.

Currently, DNA testing can identify people who have genetic heart conditions, allowing for early treatment that can prevent life-threatening heart problems.

However, more than half of people tested don’t receive a clear diagnosis, leaving families living with uncertainty, says Ward.

“This is a real concern for Māori and Pacific whānau, who have lower diagnosis rates, because most research and resources have focused on Europeans.”

Ward is using cutting-edge approaches to study patient DNA (the body’s long-term instruction manual) and RNA (the temporary working copy that carries those instructions) to understand what current tests for genetic heart disease are missing and why.

With University of Otago Professor Rajesh Katare, she is using innovative methods to turn a person’s blood cells into heart-like cells and 3D heart-like structures, which more closely reflect how genetic information is used in the heart.

“This will help us identify disease-causing changes that could be missed using blood alone,” she says.

Ward has received a fellowship and a $250,000 grant for her three-year project, which also aims to uncover genetic causes that are missed by standard testing.

“We want to help more families get life-saving answers before tragedy occurs,” she says.

Reducing the risk of aortic tears

A University of Auckland team is investigating whether the body’s fight-or-flight response drives dangerous blood pressure spikes after tears in the aorta.

Many people die before reaching hospital when the wall of their main artery, the aorta, is torn, says Dr Ryan Sixtus.

“Even with emergency treatment, there’s a significant risk of death for people with aortic tears – a condition known as aortic dissection,” he says.

Sixtus was awarded $373,530 from the Heart Foundation to investigate why many aortic dissection survivors experience dangerously high blood pressure, despite treatment.

He is part of a University of Auckland collaboration led by Associate Professor Nishith Patel and Professor James Fisher. They will investigate whether an overactive sympathetic nervous system, the body's 'fight-or-flight' response, is linked to sudden blood pressure surges after aortic tears.

"When the sympathetic nervous system is activated, it acts as the body's accelerator.

"For a lot of survivors and people with high blood pressure, this accelerator is jammed on,” says Sixtus.

High blood pressure is the most common risk factor for aortic dissection, placing ongoing strain on weakened artery walls after a tear.

However, many survivors of aortic ruptures have resistant hypertension – their blood pressure stays high, despite taking several medicines.

"The aortic dissection community have told us one of the biggest challenges they face is controlling their blood pressure. They don't want to be dying from further complications. They want to be able to live their lives without fear.

"These are people who may be doing everything right, taking multiple tablets a day, yet their blood pressure still won't budge. That tells us we might not be correctly targeting the underlying problem."

The researchers will measure sympathetic nerve activity in aortic dissection survivors and assess how it affects blood pressure control, arterial health and responses to everyday situations, such as exercise, cold temperatures and mental stress.

"What we need to do first is show that the accelerator is on and not coming unstuck. If that's proven, it could offer a new direction that allows us to more effectively control blood pressure by targeting or dampening down the fight-or-flight response," says Sixtus.

Tackling recurring heart attacks

Dr Nikki Earle is leading a group of New Zealand researchers developing new ways to identify when people are at high risk of recurring heart problems.

“After a first heart attack, people are at high risk of recurrent heart problems, and women, Māori, and Pacific peoples have a particularly high risk,” says Earle.

She received a $116,243 grant from the Heart Foundation to support the Multi-Ethnic New Zealand Study of Acute Coronary Syndromes (MENZACS).

This research tracks more than 2,500 New Zealanders who have suffered a heart attack.

The study is analysing heart biomarkers, genetics and heart disease risk factors such as nutrition, stress and exercise.

“The aim is to combine all this information to more clearly understand who is at greatest risk of recurring heart problems,” Earle says.

Women’s heart health is a particular focus for the study, which is also examining how hormones influence recovery after a heart attack.

Earle hopes the collaborative research will pave the way for more personalised, equitable care to help people stay healthier after a heart attack.

AI to streamline heart imaging

Dr Debbie Zhao has been awarded $406,575 to improve heart imaging using AI and advanced computer modelling.

“We’re hoping that by combining artificial intelligence with advanced heart modelling, we will be able to detect signs of heart disease earlier, make assessments more consistent, and help people access treatment faster,” Zhao says.

Her research will explore how AI can recognise and measure heart structures within routine echocardiograms – ultrasound scans that show how well the heart is pumping and valves are working. This will reduce the manual work required from sonographers and cardiologists.

Patients in some parts of New Zealand are facing wait times of many months for an echocardiogram, she says.

“If we can make echocardiography services more efficient, we can help more patients access high-quality cardiac assessment sooner,” Zhao says.

Developing new artificial hearts

A University of Auckland team is developing artificial hearts that could take over pumping blood in people with heart failure.

Biomedical engineering student Jerry Chuang has received $3,000 from the Heart Foundation for the project.

Artificial hearts are mechanical devices that provide a temporary solution while patients wait for a heart transplant from someone who has consented to donating organs after their death.

“We’re aiming to create artificial hearts that are safe and reliable for people of different ethnicities, ages, genders, and sizes.

“We want to develop better artificial hearts, so patients have fewer complications and a better quality of life,” says Chuang.