The title says it all, Australian doctors successfully transplanted a dead heart into a living person to save living person. Admittedly, the dead heart was inky dead for ~3 minutes, before it was put into its new home. The dying patient was lying on the operating table with his chest open as the doctors waited for him to die. The donor died, the heart was removed, and the heart was moved into its new home quickly enough that the heart was undamaged. Unfortunately, with time constraints on decay and such on important organs like the heart, this is only viable if the donor dies in the hospital. Even providing CPR to a deceased person to keep oxygen going to the heart, the maximum time for a transplant is ~15 minutes. (Though CPR can save a non-donor patient for up to 45 minutes if done correctly.) There just aren't enough (biological) hearts to around, and researchers are still trying to perfect artificial hearts in the meantime. Something with literally no shelf life, that can be activated when it is needed.