Outcomes of Heart Transplantation in Adults with Congenital Heart Disease Following the UNOS Allocation Policy Change

Abstract

PurposeMedical advances in congenital heart disease have led to a growing population of patients with adult congenital heart disease (ACHD) requiring heart transplantation (HT). The 2018 UNOS Allocation Policy Change adjusted listing of patients with CHD from Status 1B to Status 4, and clarified guidelines for upgrading listing based on exception criteria. We aimed to compare characteristics and outcomes of ACHD patients following the new allocation system.MethodsThe UNOS database was queried for ACHD patients who had undergone HT 1 year prior to the allocation policy change (n=54) and 1 year after the change (n=71). Baseline characteristics were compared via standard statistical analysis, reported in median and IQR. Kaplan Meier survival analysis (censored at 6 months) and univariate Cox regression were performed. Multivariate Cox proportional hazard regression analysis was adjusted for age, donor age, creatinine, bilirubin, dialysis, and ischemic time.ResultsAt time of listing, the post-policy change group had a significantly higher pulmonary artery diastolic pressure (19 mmHg vs. 15 mmHg, p = 0.036), and at time of transplant, had a lower cardiac output (4.0 L/min vs. 4.5 L/min, p=0.03) and lower cardiac index (2.1 L/min/m2 vs. 2.3 L/min/m2, p = 0.047). There was no significant difference in survival between the two groups at 180 days (Figure, p = 0.38). In relation to the policy change, multivariate Cox analysis hazard ratio (HR) was 1.28 [0.40, 4.19]. The post-policy change had also significantly increased hazard with worse serum creatinine (HR 4.57, [1.14, 18.3]) and longer ischemic time (HR 1.86, [1.17, 2.94]).ConclusionThere was no significant difference in 6 month mortality or outcomes in HT recipients with ACHD following the policy change despite worse hemodynamics and renal function post policy change. Continued data analysis is warranted to understand the long term effects of the allocation system and its unintended consequences. Medical advances in congenital heart disease have led to a growing population of patients with adult congenital heart disease (ACHD) requiring heart transplantation (HT). The 2018 UNOS Allocation Policy Change adjusted listing of patients with CHD from Status 1B to Status 4, and clarified guidelines for upgrading listing based on exception criteria. We aimed to compare characteristics and outcomes of ACHD patients following the new allocation system. The UNOS database was queried for ACHD patients who had undergone HT 1 year prior to the allocation policy change (n=54) and 1 year after the change (n=71). Baseline characteristics were compared via standard statistical analysis, reported in median and IQR. Kaplan Meier survival analysis (censored at 6 months) and univariate Cox regression were performed. Multivariate Cox proportional hazard regression analysis was adjusted for age, donor age, creatinine, bilirubin, dialysis, and ischemic time. At time of listing, the post-policy change group had a significantly higher pulmonary artery diastolic pressure (19 mmHg vs. 15 mmHg, p = 0.036), and at time of transplant, had a lower cardiac output (4.0 L/min vs. 4.5 L/min, p=0.03) and lower cardiac index (2.1 L/min/m2 vs. 2.3 L/min/m2, p = 0.047). There was no significant difference in survival between the two groups at 180 days (Figure, p = 0.38). In relation to the policy change, multivariate Cox analysis hazard ratio (HR) was 1.28 [0.40, 4.19]. The post-policy change had also significantly increased hazard with worse serum creatinine (HR 4.57, [1.14, 18.3]) and longer ischemic time (HR 1.86, [1.17, 2.94]). There was no significant difference in 6 month mortality or outcomes in HT recipients with ACHD following the policy change despite worse hemodynamics and renal function post policy change. Continued data analysis is warranted to understand the long term effects of the allocation system and its unintended consequences.