Kristy Collier was not expected to live a long life. At just 4-months-old, she had already suffered multiple heart attacks, and was on the brink of death until doctors made a radical decision to remove a third of her heart.

Surgeons at John Radcliffe Hospital in Oxford, England had been unable to restart her heart after a major operation – and warned her parents she was unlikely to survive.

But everything changed when they cut away a huge section of muscle in the hope her heart would start to beat again.

"She was essentially dead and was only resurrected by what I regarded at the time as a completely bizarre operation," Dr. Stephen Westaby said.

"I tried for a full 90 minutes to separate her from the heart lung machine. We got to the stage where we felt there was no hope at all."

With nothing to lose, he cut open Kirsty's heart, removed a third of her muscle wall and stitched it back together.

"I have to confess I never thought it would work," he said. "It was an awful lot smaller."

Kirsty had been born with an abnormality in her blood vessels, which starved her heart muscle of oxygen. By the time she was a few months old, she had suffered countless heart attacks, leaving her heart twice as big as it should have been.

Now, 10-years-old, Kristy is a healthy and thriving young girl who plays rugby for her school.

A recent MRI body scan shows her heart is the normal size and shape for a girl of her age. It's the first time the heart has been shown to heal itself in such a dramatic way.

"We were astonished. It was a complete revelation," said Westaby.

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