The first person to receive a heart transplant from a pig has died two months later.

David Bennett died at the University of Maryland medical center. Doctors didn't give an exact cause of death, but they said his condition had begun to get worse.

Bennett's son praised the hospital for offering the last-ditch experiment, saying the family hoped it would help end the organ shortage.

David Bennett Jr said in a statement released by the University of Maryland School of Medicine that they were grateful for every innovative moment, every crazy dream, and sleepless night that went into this historic effort.

Doctors want to use animal organs for transplants one day. Bennett, a handyman from Maryland, was a candidate for this newest attempt only because he faced certain death ineligible for a human heart transplant, bedridden and on life support, and out of other options.