Ex Vivo Allograft Perfusion for Complex Pediatric Heart Transplant Recipients

BACKGROUND Pediatric heart transplant (HTx) recipients with congenital heart defects require complex concomitant surgical procedures with the risk of prolonging the allograft's ischemic time. Ex vivo allograft perfusion with the Organ Care System (OCS; Transmedics, Andover, MA) may improve survival of these challenging patients. METHODS In this retrospective, single-center study a consecutive series of 8 children with allografts preserved using the OCS was compared with 13 children after HTx with cold storage of the donor heart from March 2018 to March 2020. RESULTS Median recipient age in the control group was 18 months (range, 1-189) versus 155 months (range, 83-214) in the OCS group, and the baseline differences between the 2 groups were not significant. Fifty percent of the children in the OCS group had complex congenital heart defects (vs 15% of the control subjects). Median operation time during HTx in the OCS group was 616 minutes (range, 270-809) versus 329 minutes (range, 283-617). Because of the time of ex vivo allograft perfusion (265 minutes [range, 202-372]) median total ischemia time was significantly shorter in the OCS group: 78 minutes (range, 52-111) versus 222 minutes (range, 74-326). The incidence of primary graft, renal, or hepatic failure did not differ between the groups. Graft function and the occurrence of any treated rejection at follow-up revealed no significant difference between the 2 groups. One-year survival was 88% in the OCS group (vs 85%). CONCLUSIONS Ex vivo allograft perfusion enabled complex pediatric HTx, yielding outcomes as positive as those of children whose donor hearts were stored in ice-cold solution. (C) 2021 by The Society of Thoracic Surgeons

Automated summary

This study compared pediatric heart transplant recipients with donor hearts preserved using the OCS system and cold storage method. The OCS group had significantly shorter median total ischemic time, with comparable outcomes in terms of primary graft, renal or hepatic failure, graft function, rejection occurrence, and one-year survival rate compared to the control group.