Functional status predicts pediatric heart transplant outcomes: A united network for organ sharing (UNOS) database study

Abstract

Functional status predicts waitlist survival in adult heart transplantation and is an independent predictor of outcomes in pediatric liver transplantation. This has not been studied in pediatric heart transplantation. Study aims were to determine the association of: (1) functional status at listing with waitlist and post-transplant outcomes, and (2) functional status at transplant with post-transplant outcomes in pediatric heart transplantation. Retrospective United Network of Organ Sharing database study of pediatric patients listed for heart transplant between 2005 and 2019 with Lansky Play Performance Scale (LPPS) scores at listing. Standard statistical methods were used to assess relationships between LPPS and outcomes (waitlist and post-transplant). Negative waitlist outcome was defined as death or removal from waitlist due to clinical deterioration. There were 4,169 patients identified, including 1,080 with LPPS 80-100 (normal activity), 1,603 with LPPS 50-70 (mild limitations), and 1,486 with LPPS 10-40 (severe limitations). LPPS 10-40 correlated with negative waitlist outcomes (HR 1.69, CI 1.59-1.80, p < 0.0001). While LLPS at listing had no association with post-transplant survival, those with LPPS 10-40 at transplant had inferior 1-year post-transplant survival compared to those with LPPS ≥50 (92% vs 95%-96%, p=0.0011). Functional status was an independent predictor of post-transplant outcomes in patients with cardiomyopathy. A functional improvement of ≥20 points between listing and transplant (N=770, 24%) was associated with higher 1-year post-transplant survival (HR 1.63, 95% CI: 1.10-2.41, p=0.018). Functional status is associated with waitlist and post-transplant outcomes. Interventions targeting functional impairment may improve pediatric heart transplantation outcomes.