A renowned Oxford heart surgeon has unveiled the prototype for a miniature artificial heart which could save hundreds of babies' lives.

Prof Stephen Westaby teamed up with American engineer Robert Jarvik and the Texas Heart Institute to create the revolutionary devices, which will cost £50,000 each.

The tiny blood pump would fit inside the baby's heart and help it rest, allowing the diseased organ to improve the way it works and in some cases, heal itself. The new technology was unveiled for the first time on Wednesday, following the Oxford Mail's story about it five months ago.

Prof Westaby, who is based at the John Radcliffe Hospital in Headington, said: "It's not going on anywhere else in Europe -- only myself and one American team have access to this."

He has already successfully used a Jarvik 2000 Heart Pump on adults. The pumps are about the size of a cork and take over a diseased heart's job of pumping blood around the body.

The children's pump, which should be ready for use in the next 18 months, is about half the size, while the infant model is the size of an adult fingernail.

Prof Westaby first app- roached Mr Jarvik about the idea of a miniature artificial heart 10 years ago, after realising there would never be enough transplants for people who needed them. He said: "It fits inside the patient's own heart and rests the patient's heart. We found while doing that because of the rest, the patient's heart gets better.

"We have been trying to work out why it gets better and how genetically."

He said the technology was still only a prototype and had not yet been used in humans.

But he added: "It looks very good. We are hoping to use it in humans as soon as the regulatory authority approves it, in about one year or 18 months.

"We're not competing with transplantation. That's been excellent, but so few patients can get a transplant."

Prof Westaby has also helped set up a research project between America and the UK.

The team plans to use a £57m computer for bioengineering, based at the University of Wales, to make a smaller and cheaper design.

Prof Westaby said the pioneering technology could also be used to prevent death during a heart attack.