Scientists from University of Louisville, Ky., are currently attempting to create a whole human heart using 3-D printers, which have already made more simple body parts such as splints, valves, ears, bladders and windpipes.

The 3-D printer works in similar way as an inkjet printer does, with a needle squirting material in a predetermined pattern. The cells get purified in a machine and then printing will be divided up into sections, using a computer model to build the organ, layer by layer.

Dr. Stuart Williams, a cell biologist leading the project at the Cardiovascular Innovation Institute -- a partnership between the university and Jewish Hospital in Louisville -- uses a mixture of a gel and living cells to gradually build the shape. The cells will eventually grow together to form the tissue.

So far, the team was able to print human heart valves and small veins with cells, and test the tiny blood vessels in mice and other small animals. Dr. Williams believes that it will take three to five years to print parts and assemble an entire heart, which will be called the "bioficial heart": a blend of the natural and artificial. Moreover, the heart can be tested in humans in less than a decade.

An organ built with cells taken from a patient's fat can solve the rejection problem that some patients face with donor organs or artificial heart, and eliminate the need for anti-rejection drugs. The patients with failing hearts that are not candidates for artificial ones, including children whose chests are too small for an artificial organ, will be the first ones to undergo the transplantation. In the future, the 3-D printer will be able to create the whole structure in less than three hours.