In an unprecedented surgery, a 57-year-old patient with terminal heart disease received a successful transplant of a genetically engineered pig heart and is still doing well three days later. The Portuguese-language news site, e- Global, reports that the patient is still doing well three days later.

According to the website publication, the historic surgery was conducted by faculty from the University of Maryland School of Medicine (UMSOM) at the University Maryland Medical Center (UMMC).

The transplant demonstrated for the first time that a heart from a genetically engineered animal can function like a human heart without immediate rejection by the body.

The patient, who answers to the name of David Bennett, is being carefully monitored, and in the next three days it will be possible to determine whether the transplant offers life-saving benefits.

David Bennett had been deemed unreadable for a conventional heart transplant at UMMC, as well as several other transplant centers that reviewed his medical records.

"It was either die or have this transplant. I want to live. I know it's a long shot, but it's my last choice," Bennett said, a day before the surgery was performed. The patient had been hospitalized and bedridden for the past few months. "I'm looking forward to getting out of bed after I recover," he finished.