UPDATE: as of July 25, 2022, MIT Technology Review reports that a porcine virus might be connected to the patient’s fatal heart failure issues – even though genetically modified pigs used for transplant organ production are intended to be virus-free. Due to the patient’s extremely fragile health state, it’s likely that even a virus-free heart transplant would have come with life-threatening complications. However, researchers may still have been able to detect the presence of the virus ahead of time and reduce the associated risks with stringent testing. Read more here.
In January 2022, a 57-year-old patient received a modified pig heart. For two months, the transplant appeared to be a success. The recipient ultimately passed away—but not from organ transplant rejection.
According to researchers, the pig heart functioned well for weeks before the patient began to experience heart problems. Despite receiving a non-human heart, the patient showed no signs of transplant rejection—a common and potentially life-threatening issue for transplant patients across all organ types, and a leading concern associated with animal-to-human transplant technology.
The patient was not a fit for an LVAD or a traditional heart transplant, making this experimental option a last resort. The option remains controversial for future patients—some medical ethicists believe the long organ transplant waiting list is not enough of a justification for such a risky procedure.
As with the pig kidney transplant to a human patient in October 2021, the heart came from a pig that had been genetically altered to reduce the risk of rejection. These modified pigs have been in the works for multiple decades from a single provider.
Xenotransplantation (animal-to-human transplants) could become a critical source of hope for patients in the future. In fact, further human trials with modified animal organs are expected to kick off within the next few years. In July 2022, the families of two patients with no brain activity successfully received pig hearts to allow medical professionals the opportunity to further study the impact of xenotransplantation on human patients.Written by Emily Progin