A 12-year-old girl is believed to have become the first UK heart transplant patient to have her donor organ removed and her own heart restarted.
Hannah Clark of Mountain Ash, south Wales, underwent the groundbreaking surgery at Great Ormond Street hospital after her body rejected her donor heart.
The operation, which took place on February 20th, occurred ten years after Hannah's original transplant.
The same surgeon who carried out Hannah's first operation came out of retirement at the request of Hannah's parents in order help reconnect the schoolgirl's dormant heart, which had never been removed from her body.
Heart specialist Sir Magdi Yacoub had previously operated on Hannah when she was aged just two and suffering from cardiomyopathy, a condition which made her heart double in size and which could have killed her within a year if untreated.
A routine check-up last November showed that her body had begun to reject the transplant organ.
Hannah's mother Elizabeth said surgeons had initially been reluctant to remove the donor heart and reconnect the dormant one, as the procedure had never been done before.
But weeks later, Sir Magdi was again looking after his former patient by advising surgeons who agreed to perform the life-saving operation.
A spokesman for Great Street Ormond hospital said: "We are delighted that Hannah is doing so well.
"We believe that this combination of circumstances is the first for children or adults in the UK."