When car enthusiast and world-renowned medical scientist Julian Paton bought the oldest Land Rover in New Zealand, he sensed an opportunity. He decided to drive the vehicle, made in 1948, way from Dunedin to Auckland and use the journey to raise funds for a life-saving innovation.
Paton is the director of Manaaki Manawa, the Centre for Heart Research at the University of Auckland, where he is leading attempts to develop a revolutionary new heart valve and improve the lives of children with rheumatic heart disease.
“The situation with rheumatic heart disease in this country is a national embarrassment,” says Paton. “I’m horrified when I see these children needing to have multiple risky and painful cardiothoracic operations throughout their life. And 40% of these kids are dead by the age of 20, which tells you that things aren’t working well.”
Rheumatic heart disease is caused by a common bacteria Group A Streptococcus. Many children carry this bug in their throats without ever knowing it. But for some, a Group A strep infection leads to a painful sore throat, fever, swelling and aches in the joints, and if untreated causes inflammation in the heart, creating lasting damage to valves.
In most developed countries, rheumatic fever is now a rare condition. In New Zealand, the problem persists, particularly among Māori and Pasifika school-age children. It is associated with badly ventilated, poorly heated, overcrowded housing.
Efforts are underway to develop a vaccine and to improve methods of delivering the regular injections of penicillin that prevent heart damage in those who have already had a bout of rheumatic fever.
Paton is aiming for a better solution for those children whose mitral or aortic valves have been so badly affected by rheumatic fever that they no longer open and close properly, so can’t pump blood in the right direction.
“As a result, you get congestion and heart failure. It’s awful to see heart failure in a child. They should be jumping around and lively, but instead they’re breathless and have no energy.”
With rheumatic heart disease, valves are often beyond repair and the only option is to replace them. The problem with artificial valves is they can lead to blood clots forming, which means patients usually need to take anti-coagulants for the rest of their lives. This in turn increases the risk of internal bleeding.
While mechanical valves can be engineered to any size, they don’t grow and can’t be enlarged, meaning a child faces future surgeries. Meanwhile, biological valves, which can be constructed from animal tissue, carry problems with rejection and may quickly degenerate.
Working with a multidisciplinary team at the university, Paton wants to develop a heart valve using a child’s own tissue, one that will grow as they do. “Then we’d have a valve that would perfectly fit that patient and we’d avoid the problem of rejection.”
The plan is to take a sample of skin cells from a child and essentially turn back the clock on the cells, allowing them to behave like stem cells. A three-dimensional image of the child’s damaged valve would be taken and a replacement engineered using a 3D printer.
“The trick would be to use a material in the printer that allows and supports the growth of cells. Once we’ve got the living valve, we’d pressure test it then implant it in a lamb’s heart to monitor its integrity and make sure it grows as the lamb becomes a sheep.”
Paton raised some money to fund the project while heading north in his historic Land Rover (hitting the headlines in Wellington when Act leader David Seymour attempted to drive it up Parliament’s steps and re-enact an event from decades ago). “By the time I reached Auckland, I was carrying about $6000 in cash,” he says.
The Land Rover continues to make appearances at car shows, and Paton is collecting funds on the Drive4Hearts JustGiving page. The goal is to raise $100,000 – so far, $70,000 has been raised.
“An old Land Rover’s engine is full of valves,” says Paton. “The car attracted attention wherever we went and brought out people, especially in rural communities, so I think we’ve already done a lot of good in reminding New Zealanders to take care of their hearts.”
