Soon, an assembly line for hearts!

Artificial hearts , say scientists who are growing thehuman organsin laboratory using stem cells, an experiment which they claim would offer hope for millions of cardiac patients worldwide.

A team , led by Doris Taylor of the University of Minnesota , which is carrying the experiment , believes the artificial organs could start beating within weeks, and would pavethewayfor livers ,lungs or kidneystobe madetoorder.

To create the artificial hearts , the scientists have removed muscle cells from donor organs to leave behind tough hearts of connective tissue. Subsequently , they injected stem cells which multiplied and grew around the structure , turning into healthy heart cells, the Daily Mail reported.

"The hearts are growing , and we hope they will show signs of beating within the next weeks. There are many hurdles to overcome to generate a fully functioning heart ,but my prediction isthat it may one day be possible to grow entire organs for transplant ," Taylor was quoted assaying.

Patients given normal heart transplants must take drugs to suppress their immune systems for the rest of their lives. This can increase the risk of high blood pressure , kidney failure and diabetes . If new hearts could be made using a patient's own stem cells, it is less likely they would be rejected . The lab-grown organs have been created using these types of cells — the body's immature "master cells" which have the ability to turn into different types of tissue.

The experiment follows a string of successes by the team trying to create spare body parts for transplants .They have already created beating rat and pig hearts . Although they were too weak to be used in animals , the work was an important step towards tailormade organs . In their latest research , reported at the American College of Cardiology's annual conference in New Orleans , they created new organs using human hearts taken from dead bodies.

However, the race to create a working heart faces many obstacles . One of the biggest is getting enough oxygen to the organ through blood vessels.