Genetically Modified Porcine-to-Human Cardiac Xenotransplantation.
Level 4 - case-series / case-control
Single-patient clinical case report
PubMed 35731912 · doi:10.1056/NEJMoa2201422
What was done
A 57-year-old man with nonischemic cardiomyopathy dependent on venoarterial extracorporeal membrane oxygenation (ECMO), ineligible for a standard allograft, received a heart xenograft from a donor pig modified with 10 gene edits. Immunosuppression was centered on CD40 blockade. The patient was monitored for graft function and rejection, with postmortem autopsy and histologic examination performed following graft failure.
What was found
The patient was successfully weaned from ECMO, and the xenograft functioned normally with no apparent rejection initially. On day 49 post-transplant, sudden diastolic thickening and xenograft failure developed, leading to withdrawal of life support on day 60. Autopsy demonstrated an edematous graft that had nearly doubled in weight. Histology revealed scattered myocyte necrosis, interstitial edema, and red-cell extravasation without microvascular thrombosis, findings inconsistent with typical rejection patterns.
Why it matters
This report establishes initial clinical feasibility that a genetically modified porcine heart can support human circulation for weeks under CD40-blockade immunosuppression, while identifying an atypical mode of graft injury that requires further mechanistic study.
Limits
The study is limited to a single patient (n=1) with severe pre-existing illness on ECMO support. The exact biological mechanism underlying the sudden diastolic thickening and delayed graft failure was not identified in the abstract.
Cited by
- supports A genetically modified pig heart was recently transplanted into the first human recipient.