The Sydney-based medical team said Friday they had spent 12 years developing the technique allowing hearts which had stopped beating for 20 minutes to be resuscitated and transplanted into a living body.

The surgeons from St Vincent's Hospital and the Victor Chang Cardiac Research Institute believe the innovation will make more hearts available to patients waiting for a transplant.

"The number of transplants that can be done will be increased. We're going to be able to do transplants we couldn't do before... This is not a minor breakthrough," Professor Bob Graham, who led the research team, told national broadcaster the ABC.

"There's no doubt that this technique can be applied worldwide and can help 30 to 40 per cent of people that can't be helped at the moment."

Until now, doctors have relied on using the still-beating hearts of donors who have been declared brain dead, then rushing the recovered organs to their waiting recipients. This means a transplant can only be performed when the donor and recipient are at the same place. But with the new technique this doesn't necessarily have to be the case.

The medical researchers developed a portable unit that can resuscitate a heart, and keeps blood flowing through the heart tissue. Once the organ is transferred to the machine, it is also covered in a preservation fluid that allows it to cope with an oxygen shortage.

"This breakthrough represents a major inroad to reducing the shortage of donor organs," said Professor Peter MacDonald, medical director of the St Vincent's Heart Transplant Unit.

Pioneering heart machine

Doctors believe the innovative machine could also increase safety for patients because it shows surgeons ahead of the operation how well the organ was functioning.

"This way we already know it's functioning well before we put it into the patient. That's a very important feature," Graham told the ABC.

So far three people have successfully undergone the procedure with hearts that stopped beating. Two are recovering well, and the third most recent recipient is still in intensive care.

Fifty-seven-year-old Michelle Gribilas was the first patient to undergo the new transplant method three months ago. She says she felt very sick before the operation.

"Now I'm a different person altogether…I feel like I'm 40 years old. I'm very lucky," she said.

The world's first successful heart transplant surgery was performed by surgeon Christian Barnard in Cape Town, South Africa, in 1967.

nm/jr (AFP, dpa)