In early February, an Australian man in his 40s became the first person in the world to leave hospital with a virtually unbreakable heart made of metal.

‘Beating’ in his chest was a titanium pump about the size of a fist. For 105 days, the metal organ’s levitating propeller pushed blood to the man’s lungs and kept him alive as he went about his usual business.

On March 6, when a human donor heart became available, the man’s titanium heart was swapped out for the real thing. Doctors say without the metal stop-gap, the patient’s real heart would have failed before a donor became available.