A Brisbane-based team has achieved what many thought impossible.
Biomedical engineer Dr Dan Timms and intensive care Associate Professor John Fraser have teamed up in Prince Charles Hospital to design and develop BiVACOR – a revolutionary artificial heart, set to save thousands of lives.
The fist-sized, titanium device could also vastly improve the quality of life for many hundreds of thousands more people waiting for transplants and others whose hearts require temporary assistance due to viral infections and autoimmune illnesses.
Dr Timms said the deceptively simple device uses magnetics, a spinning disc and centrifugal force to pump blood around the body. Five years in the making, it’s small, reliable and has a balanced blood flow, a winning combination that gives it the edge over current products.
According to Dr Timms, the BiVACOR’s design advantages include the fact that it is small enough to implant in an 8 year old child, but powerful enough to support an adult. It’s also designed to function for more than 10 years and allow recipients to live a relatively normal life.
“Typically the left side of the heart fails first because it has to work harder than right, pumping blood around the whole body,” Dr Timms said.
“It may then be followed by the right side which will experience additional workload when we connect the patient to a heart pump.”
Currently, many patients with heart failure at the hospital are connected to two Thoratec PVAD pumps – clunky 450g devices that sit outside the body in a bra-like bag – one for each side of the heart.
The devices are connected to the heart and arteries via four large tubes that must be kept in open wounds, a harbinger for infection. They are connected to a 200kg air compressor which renders the patient bed-ridden. Most never leave hospital unless they are one of the lucky few who receive a heart transplant.
“A Thoratec PVAD pump has a maximum life of two years as its balloon-like internal lining is under enormous pressure and inevitably breaks,” Dr Timms said.
“They are uncomfortable and noisy and very susceptible to infection.”
Dr Timms started developing his understanding of artificial hearts in 2001 at Queensland University of Technology and in 2004 transferred his research lab to Prince Charles Hospital, Australia’s largest cardiac hospital.
There he teamed up with Chief Medical Officer, Professor Fraser, who brought the first-hand experience of the intensive care unit and cardiac theatre.
“Around the world everyone is jealous of the fact we have an engineering lab within three minutes’ walking distance to cardiac theatre,” Professor Fraser said. “I can call Dan into ICU and he can see things happening in theatre.”
Prof Fraser said it was unusual to have a biomedical engineer based in hospital and many medics were sceptical that a device could be developed to replace both sides of the heart.
The team proved the concept worked in pre-clinical trials in 2007, and has since developed the magnetic levitation system after enlisting an electro-magnetics group in Japan’s Ibaraki University.
Dr Timms spent two years in at Germany’s Helmholtz Institution to reduce device size and learn how to manufacture it.
The team is also engaging PhD fellows in New South Wales and Malaysia to help develop the mathematical formulas to control blood flow from the disc to allow the recipient to vary exertion and movement while maintaining a normal blood flow.
The beauty of the BiVACOR design is its simplicity: it has only one moving part, meaning less can go wrong. In its current form, it requires one cable out of the body; however the team is investigating a wireless energy transfer system to eliminate the need for external cables altogether.
BiVACOR will be able to be implanted below the diaphragm and plumbed into the heart to take all the work away from the heart and allow recovery. It could also completely replace the heart as an alternative to transplant, particularly in older patients who are unlike to qualify for a transplant.
Professor Fraser said around 300,000 Australians experienced heart failure every year but there were less than one hundred heart transplants performed in Australia a year (and in fact only around 3000 heart transplants a year worldwide) as there were few donors and many complexities.
BiVACOR has been endorsed by key opinion-leaders in the US including the Texas Heart Institute which was so impressed it offered to run pre-clinical trials of the improved device.
Dr Timms and Prof Fraser are fending off such offers from international interests in the hope of securing government and private backing in Australia.
They are seeking $10M to accelerate the research and pre-clinical trials required to progress BiVACOR to market.
They hope to have it ready in three years.
“We’ve had to be resourceful and collaborate with international scientists,” Prof Fraser said.
“And it couldn’t have been done without assistance from the Prince Charles Hospital Foundation, Baulderstone and Stenning, as well as a team of biomedical engineers and medical PhD students volunteering their time and working tirelessly to assist the development and bring it to pre-clinical trials.”
BiVACOR is one of several cardiovascular projects being developed by the research team within the Icetlab, a centre for innovation and excellence in mechanical cardiovascular devices.