London - A doctor spoke on Thursday about how he helped remove a 12-year-old girl's donor heart, which she had started to reject, and restart her own, dormant heart in a pioneering operation in London.
Heart specialist Sir Magdi Yacoub advised the surgeons who carried out the procedure on Hannah Clark - understood to be a medical first in Britain - in February after he came out of retirement at the request of the girl's parents.
"Her own heart has recovered. It really is absolutely wonderful news," Yacoub told BBC News.
The girl had enjoyed good health with the donor heart until November when a cardiologist found that her body was rejecting the organ, which Yacoub had transplanted 10 years ago in a life-saving operation.
Clark had been suffering from cardiomyopathy, which made her heart double in size and threaten to fail within a year.
Yacoub explained that a transplant patient's original heart was not normally left inside the body, but doctors had thought ahead in Clark's case.
"At the time we had the idea that she had this very severe muscle disease and there was the outside possibility that her heart would recover," he said.
"That was the idea and it worked out, so that was wonderful.
"Now she is a happy little girl with her own normal heart. The complications have all gone. This is a very happy ending."
Clark's mother Elizabeth said surgeons at Great Ormond Street Hospital in London were initially reluctant to remove the donor heart and reconnect the dormant one because they said it had never been done before.
Weeks later, the transplant team agreed to perform the complicated operation with help from Yacoub.
Professor Peter Weissberg, medical director of the British Heart Foundation (BHF), hailed the outcome as an "exciting and important event".
He said: "Surgeons like BHF Professor Sir Magdi Yacoub have thought for some time that if a heart is failing because of acute inflammation, it might be able to recover if rested.
"This seems to be exactly what has happened in this case."
The donor, or "piggy back", heart enabled the patient's own organ to take a rest, noted Weissberg.
"This is a great example of how a pioneering and novel approach to a medical problem can lead to surprising results that tell us a lot about how some heart diseases progress," he said.
"In the past, patients with inflamed hearts either died or were transplanted before their own hearts had any chance of recovery."
Elizabeth Clark said she had expected the operation on February 20 to take eight hours but her daughter was out in just four.
The procedure went so well that the girl was able to return home within five days instead of being in intensive care for months as feared, she said.
"Nobody thought she would be like she is now. She is just enjoying her life and is looking forward to going back to Mountain Ash Comprehensive school (south Wales) after Easter," Elizabeth Clark said.
Another benefit of the operation is that she will not longer have to take the strong anti-rejection drugs necessary while she had the donor heart.
Hannah Clark has also battled lymph cancer for the past few years but is currently in remission after a successful course of chemotherapy in January of this year. - Sapa-AFP