The concept of 3D-printed organs has long been touted as a possible solution to the long waiting lists for transplantation. Now scientists in Israel have pumped fresh blood into the idea by printing a miniature “living” heart using a patient’s own tissue as the “ink”.

The Lilliputian organ — about the size of a cherry, while an adult heart is the size of a fist — is living in the sense that it is “vascularised”, meaning it contains blood vessels. It demonstrates that bioprinting can potentially recreate not just the structure of an organ but also the pipework needed for it to function. 

“This is the first time anyone anywhere has successfully engineered and printed an entire heart replete with cells, blood vessels, ventricles and chambers,” said Tal Dvir, the Tel Aviv University professor leading the research. The revelation was published last month in the Advanced Science journal. Sceptics point out that this tiny heart cannot pump, and fully functioning bioprinted organs remain a distant hope.