A. Marion Ybarra

BACKGROUND: Fontan circulatory failure (FCF) is a chronic state in palliated single ventricle heart disease with high morbidity and mortality rates, including heart failure, multisystem end-organ disease, and need for heart transplant. Specific FCF morbidities have not been rigorously defined, limiting study of how FCF morbidities affect pre–heart transplant and post–heart transplant outcomes. We hypothesized that FCF-related morbidities affect survival from heart transplant waitlisting through 1 year after heart transplant. METHODS: This 20-center, retrospective cohort study collected demographic, medical/surgical history, waitlist, and peri- and post–heart transplant data, and a priori defined FCF-specific morbidities, in Fontan patients who were listed for heart transplant from 2008 through 2022. Univariate 2-group statistics compared surviving individuals with those who died anytime from waitlisting to 1 year after heart transplant, died on the waitlist, or underwent transplant and died within 1 year after transplant. Using covariates from both univariate analyses, multivariable logistic regression determined the primary study outcome of independent FCF risk factors for death between waitlist and 1 year after heart transplant. RESULTS: Of 409 waitlisted patients, 24 (5.9%) died on the waitlist. Of the 341 (83.4%) who underwent transplant, 27 (8.5%) did not survive to 1 year. Univariate risk factors for waitlist death included higher aortopulmonary collateral burden, >1 hospitalization in the previous year, younger age, sleep apnea, higher New York Heart Association class, nonenrollment in school or work, and single-parent home. Risk factors for 1-year post–heart transplant mortality included hypoplastic left heart syndrome diagnosis, patent fenestration, anatomic Fontan obstruction, clinical cyanosis (pulse oximetry 1 hospitalization in the year before waitlisting (adjusted odds ratio, 2.0 [95% CI, 1.0–4.1]; P =0.05) and clinical cyanosis (adjusted odds ratio, 5.0 [95% CI, 1.8–13.4]; P =0.002). CONCLUSIONS: Patients with Fontan palliation selected for heart transplant have substantial mortality rates from waitlisting through transplant. Among FCF-specific morbidities, cyanosis is associated with worsened survival and necessitates further study. Clinical morbidity of any type requiring repeated hospital admission also should prompt consideration of heart transplant.

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.

Background: Treatment of post‐transplant lymphoproliferative disease (PTLD) varies, with only some patients receiving chemotherapy. Concern for chemotherapy toxicities may influence treatment decisions as little is known regarding the late effects (LE) in PTLD survivors. This report characterizes LE in PTLD survivors at our institution.Procedure: Pediatric patients (0–18 years old) diagnosed with PTLD from 1990 to 2020 were examined. All patients included survived 6 months after completing chemotherapy or were 6 months from diagnosis if received no chemotherapy. Treatment with anti‐CD20 antibody (rituximab) alone was not considered chemotherapy. Toxicities were classified per Common Terminology Criteria for Adverse Events Version 5.0. Chi‐square tests assessed differences between categorical groups, or Fischer's exact test or the Fischer–Freeman–Halton exact test for limited sample sizes.Results: Of the 44 patients included, 24 (55%) were treated with chemotherapy. Twenty‐four (55%) were alive at last follow‐up. Chemotherapy was not associated with differences in survival (odds ratio [OR] 1.40, confidence interval [CI]: 0.42–4.63;p = .31). All patients experienced LE. Grade 3 toxicity or higher was experienced by 82% of patients with no difference in incidence (OR 1.20, CI: 0.27–5.80;p > .99) or median toxicity grade (3.00 vs. 4.00,p = .21) between treatment groups. Patients who received chemotherapy were more likely to experience blood and lymphatic toxicity (58% vs. 25%,p = .03) and cardiac toxicity (46% vs. 15%,p = .03), but less likely to have infections (54% vs. 85%,p = .03).Conclusions: Survivors of PTLD experience LE including late mortality regardless of chemotherapy exposure. Further investigation to better understand LE could optimize upfront therapy for children with PTLD and improve outcomes.

Background: Fontan‐associated liver disease (FALD) uniformly affects patients with long‐term Fontan physiology. The effect of isolated heart transplant (HT) on the course of FALD post‐HT is not well understood.Methods: We evaluated serial liver imaging pre‐ and post‐HT to assess liver changes over time in a single‐center retrospective analysis of Fontan HT recipients who had pre‐ and ≥1‐year post‐HT liver imaging. Available patient demographic and clinical data were reviewed, including available liver biopsy results.Results: Serial liver imaging was available in 19 patients with a median age at HT of 12 years (range 3–23), the median age from Fontan to HT of 5.7 years (range 0.8–16), and the median time from imaging to follow up of 27 months (range 12–136 months). Pre‐HT liver imaging was classified as follows: normal (n=1), congested (n=9), fibrotic (n=7), and cirrhotic (n=2). The majority of transplanted patients (15/19) had improvement in their post‐HT liver imaging, including 13 patients with initially abnormal imaging pre‐HT having normal liver imaging at follow‐up. One patient had persistent cirrhosis at 26‐month follow‐up, one patient had unchanged fibrosis at 18‐month follow‐up, and one patient progressed from fibrosis pre‐HT to cirrhosis post‐HT at 136 months. No patients had overt isolated liver failure during pre‐ or post‐HT follow‐up. Liver biopsy did not consistently correlate with imaging findings.Conclusions: Post‐HT liver imaging evaluation in Fontan patients reveals heterogeneous liver outcomes. These results not only provide evidence for the improvement of FALD post‐HT but also show the need for serial liver imaging follow‐up post‐HT.