Surgeons in the US have carried out a successful heart transplant on a five-year-old girl using 3D printing to help them.
They used a model of her heart to work out exactly how they needed to operate cutting down the length of the procedure.
It is thought it could increase a patient's chance of survival in future.
Dr Phil Reeves is a 3D printing consultant.
“There are reports that it is nearly a thousand dollars a minute to be in the operating theatre,” Dr Reeves said.
“So if a surgeon can walk into the theatre having looked at this model beforehand, having studied it, planned the procedure in advance, that can significantly reduce the amount of theatre time which has a saving.”