US engineers develop beating patch to repair heart damage

Unlike some human organs, the heart cannot regenerate itself after a heart attack. The dead muscle is often replaced by scar tissue that can no longer transmit electrical signals or contract, both of which are necessary for smooth and forceful heartbeats.

The Duke team claims that its breakthrough – which is described in Nature Communications - could enable surgeons to patch a damaged heart with tissue made outside of the body.

Whilst researchers have been exploring the concept, this is claimed to be the first patch of its kind both large enough to cover affected tissues, and as strong and electrically active as natural heart tissue. "Creating individual cardiac muscle cells is pretty commonplace," said Nenad Bursac, professor of biomedical engineering at Duke. "Scaling it up to this size is something that has never been done and it required a lot of engineering ingenuity."

The cells for the heart patch are grown from human pluripotent stem cells - the cells that can become any type of cell in the body. Bursac and Ilya Shadrin, author of the Nature paper, have successfully made patches using many different lines of human stem cells, including those derived from embryos and those artificially forced or "induced" into their pluripotent state.