In a risky, but necessary operation, British surgeons turned around a woman's backwards heart by draining her body of blood, stopping her heart and "re-plumbing" it so that it would beat correctly.

Even more incredible, the surgeons carried out the operation in just 30 minutes.

Anita Gurung, 28, was totally paralyzed by a catastrophic stroke last year while on her way to work.

Although she regained movement in her arms and legs several days later, scans showed that major veins bringing blood back to the heart from the rest of her body were backwards, connected to the wrong pumping chambers.

Without surgery to correct the problem, she could have suffered another, potentially fatal stroke at any time.

Gurung's veins were rerouted in an incredible operation at John Radcliffe Hospital in Oxford, England.

Surgeons stopped her heart with the same drug used on death row prisoners, then drained the blood from her body.

With her head packed on ice, they had just 30 minutes to correct her reversed heart plumbing before she would suffer brain damage from lack of oxygen.

Professor Stephen Westaby, who led the operation, said despite the pressure he had been confident of success.

"Although this is a time dependent procedure, there is no need to rush it. The important thing is that what we do, we do well," he said.

Because of Gurung's "plumbing" problem, some of her blood was bypassing the lungs and unfiltered blood was reaching her brain where a clot caused the stroke.

"I have never seen this problem in 30 years of surgery. We were sure that one day she would suffer another stroke," Westaby said. "It's a very dangerous situation where blood from the body can go straight to the brain without any filter."

With the problem fixed, Gurung should not have to worry about any further strokes.

Click here to read more on this story and see photos of Gurung at Sky News.