The second major move forward for pig-human heart xenotransplantation this year was the successful transplant of two genetically modified pig hearts.

The director of the NYU Langone Transplant Institute said that seeing a pig heart beating inside a human chest was one of the most amazing things.

The first one took place in June and the second one took place in July.

There is a problem. Two transplant patients were brain-dead and their hearts were kept beating on machines in order to receive pig organs It will likely take years before pig-to-human transplant procedures can be routine and reliable for people on long waiting lists.

Montgomery is a heart transplant recipient and said there will be an iterative process of learning.

The doctor hopes that pig organs will one day be a sustainable source of organs so no one will have to die waiting.

More human trials could become reality in the next few years 

A pig-human heart transplant was performed at the University of Maryland in January. A 57-year-old man was the recipient of that transplant.

The patient, David Bennett Jr., said a day before his surgery that it was either death or a transplant. It's my last choice but I know it's a shot in the dark.

Bennett's pig heart didn't work for two months. The surgeon who operated on the pig's heart told The New York Times that there was no evidence of an active case of the disease.

We don't know why he died. He argues that it's important to do research on dead donors before moving forward with more live transplants.

The removed human heart. (Joe Carrotta/NYU Langone Health)

Chris Colbert, an ER doctor from Chicago who was not involved in the research, told Insider that it was a huge step in the right direction. An organ match is not just an organ.

Because they were engineered with 10 genetic modifications, the pig hearts were able to function for at least 72 hours inside humans. To prevent transplant rejection and abnormal growth, four of the gene edits were porcine, and six were human transgenes.

It's the next frontier in transplant medicine, according to a doctor who wasn't involved in the NYU research. It is a modern miracle that we are able to consider this.

Routine pig-to-human heart transplants could be 'very possible' within a decade 

Prilamarla says before pig-human heart transplants can become routine, doctors need to better understand how to make modified pig organs more compatible inside living people, so they won't be rejected by the recipients. She said that researchers and surgeons will need to make sure that they don't transmit an infectious disease to the human from a pig.

She said she wouldn't be surprised if pig-to-human heart transplants became common in her career.

I don't know if it will happen in the next year. She didn't think so. Do I think it will come down the line in a decade? I believe it is doable.

There is a high demand for heart transplants in the US.

There are other things that could be done to shorten wait times.

The original article was published by Business Insider.

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