American researchers say they have created the first full-size human heart model using 3D printing technology. The model was made with a specially developed 3D printer that uses biomaterials to produce a structure and tissues similar to a real human heart. The researchers say the model heart can be a useful tool to train medical professionals in operations related to human heart function. It could also be used as a basis for new research on ways to use 3D printing technology to produce fully operating hearts to replace in people. The research was led by an engineering team at America’s Carnegie Mellon University.