Predicting Graft Loss by 1 Year in Pediatric Heart Transplantation Candidates

Abstract

Background-Pediatric data on the impact of pre-heart transplantation (HTx) risk factors on early post-HTx outcomes remain inconclusive. Thus, among patients with previous congenital heart disease or cardiomyopathy, disease-specific risk models for graft loss were developed with the use pre-HTx recipient and donor characteristics. Methods and Results-Patients enrolled in the Pediatric Heart Transplant Study (PHTS) from 1996 to 2006 were stratified by pre-HTx diagnosis into cardiomyopathy and congenital heart disease cohorts. Logistic regression identified independent, pre-HTx risk factors. Risk models were constructed for 1-year post-HTx graft loss. Donor factors were added for model refinement. The models were validated with the use of patients transplanted from 2007 to 2009. Risk factors for graft loss were identified in patients with cardiomyopathy (n=896) and congenital heart disease (n=965). For cardiomyopathy, independent risk factors were earlier year of transplantation, nonwhite race, female sex, diagnosis other than dilated cardiomyopathy, higher blood urea nitrogen, and panel reactive antibody >10%. The recipient characteristic risk model had good accuracy in the validation cohort, with predicted versus actual survival of 97.5% versus 95.3% (C statistic, 0.73). For patients with congenital heart disease, independent risk factors were nonwhite race, history of Fontan, ventilator dependence, higher blood urea nitrogen, panel reactive antibody >10%, and lower body surface area. The risk model was less accurate, with 86.6% predicted versus 92.4% actual survival, in the validation cohort (C statistic, 0.63). Donor characteristics did not enhance model precision. Conclusions-Risk factors for 1-year post-HTx graft loss differ on the basis of pre-HTx cardiac diagnosis. Modeling effectively stratifies the risk of graft loss in patients with cardiomyopathy and may be an adjunctive tool in allocation policies and center performance metrics.

High Risk of Graft Failure in Emerging Adult Heart Transplant Recipients

“…In contrast, among those with at least 6 months of function, <2 year olds also showed significantly lower risks of failure than 21-24 year olds. This finding is likely related to the multiple factors that lead to higher mortality in infants early after transplant including complications associated with congenital heart disease, the possibility of allosensitization, degree of end organ dysfunction at the time of transplant, degree of support required prior to transplant, ischemic time of the donor heart, and need for support posttransplant (6,38,40,41).…”

Current state of pediatric cardiac transplantation

“…Several predictive models have been developed that take into account multiple, coexisting clinical variables/ risk factors to estimate survival; therefore, allowing for risk stratification to assist in decision-making around listing for transplantation and allocation of donor organs to specific recipients to optimize survival both pre-and posttransplant (8)(9)(10)(11).…”

Center effect on posttransplant survival among currently active United States pediatric heart transplant centers

“…12,13 We developed this model within the study cohort rather than applying one of the published models [14][15][16] because risk-models perform best within the cohort where they are developed, thereby providing an optimal risk-adjustment tool for the study cohort. 12,13 We developed this model within the study cohort rather than applying one of the published models [14][15][16] because risk-models perform best within the cohort where they are developed, thereby providing an optimal risk-adjustment tool for the study cohort.…”