Genetically Modified Porcine-to-Human Cardiac Xenotransplantation

A 57-year-old man with nonischemic cardiomyopathy who was dependent on venoarterial extracorporeal membrane oxygenation (ECMO) and was not a candidate for standard therapeutics, including a traditional allograft, received a heart from a genetically modified pig source animal that had 10 individual gene edits. Immunosuppression was based on CD40 blockade. The patient was weaned from ECMO, and the xenograft functioned normally without apparent rejection. Sudden diastolic thickening and failure of the xenograft occurred on day 49 after transplantation, and life support was withdrawn on day 60. On autopsy, the xenograft was found to be edematous, having nearly doubled in weight. Histologic examination revealed scattered myocyte necrosis, interstitial edema, and red-cell extravasation, without evidence of microvascular thrombosis - findings that were not consistent with typical rejection. Studies are under way to identify the mechanisms responsible for these changes. (Funded by the University of Maryland Medical Center and School of Medicine.) Porcine-to-Human Cardiac TransplantationIn this report, a porcine-to-human heart transplantation is described. Videos show transthoracic echocardiography in the patient who received the heart.

Automated summary

A porcine-to-human heart transplantation was performed on a 57-year-old man with nonischemic cardiomyopathy who was not eligible for standard therapeutics, including traditional allograft. The patient was successfully weaned from ECMO and the xenograft functioned normally until sudden failure on day 49 post-transplantation. Further studies are needed to identify the mechanisms responsible for the changes observed in the xenograft.