Andrea Nicole Lambert

Background: There are conflicting data regarding the relationship between center volume and outcomes in pediatric heart transplantation. Previous studies have not fully accounted for differences in case mix, particularly in high‐risk congenital heart disease (CHD) groups. We aimed to evaluate the relationship between center volume and outcomes using the Pediatric Heart Transplant Society (PHTS) Registry and explore how case mix may affect outcomes.Methods: A retrospective cohort study of all pediatric patients in the PHTS Registry who received a heart transplant from 2009 to 2018 was performed. Centers were divided into 5 groups based on average yearly transplant volume. The primary outcome was time to death or graft loss and outcomes were compared using Kaplan–Meier analysis.Results: There were 4583 cases among 55 centers included. There was no difference in time to death or graft loss by center volume in the entire cohort (p = .75), in patients with CHD (p = .79) or in patients with cardiomyopathy (p = .23). There was also no difference in time to death or graft loss by center size in patients undergoing transplant after Norwood, Glenn or Fontan (log rank p = .17, p = .31, and p = .10 respectively). There was a statistically significant difference in outcomes by center size in the positive crossmatch group (p < .0001), though no discernible pattern related to high or low center volume.Conclusions: Outcomes are similar among transplant centers of all sizes, including for high‐risk patient groups with CHD. Future work is needed to understand how patient‐specific risk factors may vary among centers of various sizes and whether this influences patient outcomes.

Psychiatric disorders are common in pediatric HTx recipients. However, the impact of psychiatric comorbidities on patient outcomes is unknown. We aimed to assess the impact of disorders of adjustment, depression, and anxiety on HTx outcomes in children; hypothesizing that the presence of psychiatric disorders during or preceding HTx would negatively impact outcomes. All pediatric HTx recipients ≥8 years of age who survived to hospital discharge were identified from a novel linkage between the PHIS and SRTR databases (2002‐2016). Psychiatric disorders were identified using ICD codes during or preceding the HTx admission. Post‐transplant graft survival, freedom from readmission, and freedom from rejection were analyzed using the Kaplan‐Meier method. Multivariable Cox proportional hazard models were used to adjust for covariates. A total of 1192 patients were included, of which 133 (11.2%) had depression, 197 (16.5%) had anxiety, and 218 (18.3%) had adjustment disorders. The presence of depression was independently associated with higher rates of readmission (60.9% vs 54.1% at 6 months) (AHR 1.63, 95% CI 1.22‐2.18, P = .001) and inferior graft survival (70.2% vs 83.4% at 5 years) (AHR 1.62, 95% CI 1.14‐2.3, P = .007). Anxiety was independently associated with higher rates of readmission (60.4% vs 53.9% at 6 months) (AHR 1.46, 95% CI 1.09‐1.94, P = .01). Anxiety and depression in the pretransplant period are independently associated with outcomes following HTx in children. Evaluation and management of psychiatric comorbidities represents an important component of care in this vulnerable population.

Rehospitalization following pediatric heart transplantation is common. However, existing data remain somewhat limited. Using a novel linkage between administrative and clinical databases, pediatric heart transplant (HT) recipients from 29 centers who survived to discharge were retrospectively reviewed to determine the frequency, timing of, and indication for all-cause rehospitalizations in the year following transplant discharge. Of 2870 pediatric HT recipients, 1835 (63.9%) were rehospitalized in the first year post-discharge (5429 total readmissions). Rehospitalization rates varied significantly across centers (46% to 100%) and were inversely correlated to center transplant volume (r² 0.25, p < 0.01). The median number of rehospitalizations per patient was 2 (IQR 1–4) and the median time to first rehospitalization was 29 days (IQR 9–99 days). Independent risk factors for rehospitalization included younger age at HT (HR 0.99, 95% CI 0.97–0.99), congenital heart disease (HR 1.2, 95% CI 1.1–1.4), listing status 1B at transplant (HR 1.3, 95% CI 1.1–1.5), and post-transplant complications including rejection prior to discharge (HR 1.5 95% CI 1.3–1.8) and chylothorax (HR 1.3, 95% CI 1.0–1.6). Cardiac diagnoses were the most common indication for rehospitalization (n = 1600, 29.5%), followed by infection (n = 1367, 25.2%). These findings may serve to guide the development of interventions aimed at reducing post-HT hospitalizations.