Abstract 15306: Annual Transplant Volume Does Not Affect Center Specific Mortality- A PHTS Database Study

Abstract

Introduction: Recent studies have suggested a relationship between mortality and center volume in pediatric heart transplantation; however, these studies utilize databases that lack granularity to assess patient risk profiles. Hypothesis: Utilizing the Pediatric Heart Transplant Society (PHTS) database, we hypothesized that there would be a difference in outcomes among centers based on yearly transplant volume, and that the patient’s clinical profiles would differ by center volume. Methods: We performed a retrospective analysis of the PHTS dataset from all pediatric (≤ 18 years of age) cases from 2009-2018. Centers were stratified into 5 groups based on annual volume: ≤ 4, 4-6, 6-9, 9-14, and > 14 transplants. We evaluated specific variables, including those identified as significant risk factors in previous PHTS studies including mechanical ventilation, PRA > 10%, high BUN, gender, and Fontan completion, within each group. We used Kaplan Meier for survival, contingency tables with Pearson Chi-square test for association, and analysis-of-variance to compare means. P< 0.05 was considered statistically significant. Results: There were 6800 cases among 55 centers. Table 1 demonstrates that there was no significant difference in one-year post transplant survival among the groups, and the patient variables showing statistically significant differences followed no specific pattern among the center volume groups. It also demonstrates that there is no clear association between cumulative risk factors within individual patients and center volume. Conclusions: One-year post transplant survival is similar within the PHTS for all centers regardless of case volume. These group differences were different for different variables and did not segregate consistently between lower volume and higher volume groups suggesting there exists a complicated relationship among risk factors and center volume.