- Video report by ITV News correspondent Ben Chapman
Jim Lynskey had open heart surgery to fit a new pump to keep his heart beating, but it has left him in incredible pain, and like nearly 300 others with similar conditions he is facing Christmas waiting for a transplant.
Without a transplant Jim - who was just two weeks old when a meningitis infection irreversibly damaged his heart - depends on machines to survive.
He has to pack vital equipment just to leave the house.
Jim is one of 298 people waiting for a transplant. Thirty-three of those on the list are children.
"You have to be appreciative, and also hope that one day this won't be forever and that I will get a transplant," he told ITV News.
But the waiting list for heart transplants has gone up by a quarter since last Christmas, a situation that has prompted the NHS to call for more people to sign up to the organ donor register.
Sally Johnson, NHS director of organ donation and transplantation, said it was important people join the register and that they tell their families that they want to donate.
That is crucial because families must consent for a loved one's organs to be donated after death.
In England the NHS is considering introducing a system where people will automatically become donors unless they opt out.
But in Wales, where such a system already exists, the number of donors has not increased.
Jim believes Christmas is the perfect opportunity for families to talk about it.
"If you had someone in your family who needed an organ you would do it without even thinking about it," he said.
"But if you're fortunate enough not to be in that situation, its something very difficult to consider and I just hope the barriers are broken down a little bit by talking about it."