A human can only live without a heart if advanced technologically produced alternatives are surgically inserted. Surgeons at the Texas Institute have devised such a thing that they tested on 50 calves before risking it on a human.
But the first man to receie it had been given only 12 hours to live with his damaged heart. The plan was to install a ‘continuous flow’ device that would allow blood to circulate his body without a pulse. This was successful and he was up talking within a day or two.