Developing a bionic pacemaker

Fifty years later, researchers at the University of Auckland’s Manaaki Manawa, the Centre for Heart Research, have taken that sci-fi dream to a new level by developing a bionic pacemaker for the heart. And, with much more than $6 million already invested in their work, they’re making Austin’s six million bucks look cheap.

Centre director Professor Julian Paton uses the analogy himself in presentations about the work, including those to potential donors, asking them to imagine its potential.

“A patient barely alive in heart failure…we can rebuild him. We have the technology. We have the capability to make the world’s first bionic human. You may be that human. Better than you were before. Better…stronger…faster.”

 And yet for Julian, the device his team has been developing since his arrival in 2017 is based not on science fiction, but the simplest of theories: “What we are doing is giving the heart a taste of its own medicine.”

Our heart rate naturally increases when we inhale and slows when we exhale (variable heart rate). It’s a rhythm that’s been preserved across species for 430 million years and one that helps repair and restore the heart when it recovers from the day’s activities.

“During the day, the heart’s working harder because we’re alert, we’re upright and it has to pump blood up into the brain. We’re exercising, it’s having a workout. It has to repair itself. It has to prepare and optimise energy for the next day. And it does that particularly at night when you’re asleep. When you’ve switched off, your brain is repairing, your muscles are recovering. And that includes your heart.”

The pacemakers inserted in around 2500 New Zealanders annually, mainly for rhythm disturbances and signalling abnormalities, have not allowed the heart to do that, firing instead at an unnatural metronomic rate. The new device Julian’s team calls Cysoni (Welsh for synchronisation), which mimics the heart’s natural rhythm, is set to change all that and save potentially thousands of lives.

By analysing the heart muscle cells of sheep with induced heart failure who’ve been wired up to the bionic pacemaker externally, they’ve discovered that it helps damaged cells in the heart muscles to repair themselves.

 In heart failure, these cells become ‘big and baggy’ as the proteins within them vital for the normal contractions that occur with every beat become scattered and ineffective.

“After our form of pacing, they’re all beautifully aligned and the cells have shrunk back to their normal size. Incredibly, the new pacemaker repairs this damage. It was a completely unexpected finding.”

The research suggests bionic pacemakers can increase the pumping ability of the heart by 25%, making them three times more effective than existing devices.

Julian says the first-line treatment for patients in heart failure is usually drugs to stimulate the remaining heart muscle.

“We need to rethink this because this pacemaker is doing things that go beyond our wildest imagination about what pacemaking can do.”

In February last year, the first patient was wired up to an external bionic pacemaker – its shoebox size prevented implantation – after coronary artery surgery at Waikato Hospital.

Since then, matchbox-sized devices have been developed in Cardiff and are due to be implanted soon in a specially bred flock of sheep at the University’s Ngapouri Research Farm near Rotorua. GPS trackers will then monitor movement of the sheep to demonstrate that the bionic pacemaker enhances exercise and prolongs life. 

Julian hopes a clinical trial to insert the new pacemakers in human patients can begin as soon as next year. 

Another transformational advance is wireless charging, being developed at the University’s Auckland Bioengineering Institute by a team led by Associate Professor David Budgett and Dr Daniel McCormick. This allows pacemakers to be recharged after implantation and provides the energy for them to co-ordinate their activity with other devices in the body.

When it’s time to recharge, electrodes are put on the body surface and small electrical currents pass near the pacemaker which captures energy to store in its battery. With wireless charging, the devices can be smaller and smarter: conventional pacemakers need to be surgically replaced to swap out the battery every 10 years or so.

The devices will establish a new standard for ‘lifelong pacemakers’. Vitally, their tiny size allows them to be located inside the chambers of the heart, delivered through blood vessels using simple surgery. The availability of power means they can communicate with each other to synchronise pacing at multiple sites, which is essential for 70% of pacemaker recipients.

“They have loads of advantages,” says David. “You don’t have leads that can break, they’re quicker to put in with lower surgical risks and you can add more devices later if needed.”

And they can use more energy to do smarter pacing. 

“Current pacemakers are very conservative in their functions because of the need to preserve power.”

David believes the new technology may be 10 years away from common use, mainly because of the transition through regulatory approval processes.

Two years after becoming one of the first private donors to Manaaki Manawa, the Centre for Heart Research at the University of Auckland, octogenarian Garth Barfoot became a heart patient himself.

In 2021, Garth’s $100,000 donation was used to buy a state-of-the-art ultrasound imaging platform for the newly launched centre. In 2023, a year after having a heart valve replaced, he was back in North Shore Hospital having a pacemaker fitted after suffering spells of dizziness caused by bradycardia (abnormally slow heartbeat). 

Garth’s name is well known through Barfoot & Thompson, the real estate company his father founded in 1923, but in more recent years, he’s forged a new reputation as a distance runner, completing more than 30 marathons and triathlons. The pacemaker enabled him to fulfil a long-held dream. In November 2024, at the age of 88, he became the oldest finisher in the New York marathon, completing the event in a gruelling 11 hours, 29 minutes and 49 seconds. The achievement had eluded him the year before when he had to pull out of the event because of the cold. 

The news that the pacemaker technology that assisted him is about to become even better doesn’t surprise Garth, who calls it a “no-brainer”. Garth has talked about the new device with its developer, Professor Julian Paton. 

“He said that when he was working, they would always look forward to the next model of car, and now, at his stage of life and after what he had gone through medically, he was waiting for the new pacemaker models to come through.”

Garth doesn’t have a wish list for a dream pacemaker. 

“But at 89, as someone who is old enough to have seen the uptake in use of pacemakers by my contemporaries, I know that with the help of researchers like Julian, we will be finding them even more useful in the future.”

Private donors like Garth are a vital source of funding for Manaaki Manawa. Others who’ve generously supported Julian’s work include the Kelliher Charitable Trust and the Heart Foundation.