Incidence, predictors, and outcomes after severe primary graft dysfunction in pediatric heart transplant recipients

Background: Previous reports of primary graft dysfunction (PGD) in pediatric heart transplant (HT) recipients are limited to descriptive series of children who required extracorporeal membrane oxygenation (ECMO) support shortly after HT. In this study we sought to determine the incidence, risk factors, and survival after severe PGD in pediatric HT recipients.

Methods: We identified all children <18 years old who underwent HT in the United States during 1996 to 2015 using the Organ Procurement and Transplant Network database and then identified those who developed severe PGD by linking patient variables to Extracorporeal Life Support Organization registry data. Logistic regression models were used to assess risk factors for developing severe PGD.

Results: The overall incidence of severe PGD was 4.7% over 20 years (95% confidence interval 4.2% to 5.3%). The incidence was 4.1%, 4.5%, 5.3%, and 4.6%, respectively, in consecutive 5-year periods (p for trend = 0.48). Independent risk factors for developing severe PGD were younger age, congenital heart disease, HT while supported on ECMO, higher serum bilirubin, and graft ischemic time ≥4 hours. Ventricular assist device support as bridge to HT and available donor variables were not associated. Death (or graft loss) before discharge occurred in 40.6% of children with PGD (105 deaths, 7 re-transplants) and in 5.6% of children without PGD.

Conclusions: Severe PGD remains an important clinical morbidity in pediatric HT recipients in the current era and is associated with high mortality. These findings highlight the need for research in preventing and treating PGD in pediatric HT recipients for improving overall post-transplant survival.