Advanced Heart Function and pHeart Transplant Fellow The Stollery Children's Hospital The University of Alberta Edmonton, Alberta, Canada
Background: Recent studies evaluating the impact of ischemic time (IT) on pediatric heart transplant (HTx) outcomes continue to advise caution when accepting grafts with IT >6h. We sought to evaluate the association between IT and clinical outcomes in a geographically remote center where a substantial proportion of HTx have prolonged IT.
METHODS AND RESULTS:
Methods: This was a retrospective single-center analysis of patients transplanted between 01/1995 and 12/2020. Orthotopic HTx occurred in 199 patients, with 11 re-transplants excluded. Baseline demographic and clinical characteristics, procurement strategies and post-HTx outcomes were collected and compared across three IT groups ( < 4.5h, 4.5–6h and >6h) with results reported in that order. Survival analysis was performed using the Kaplan-Meier method and Cox proportional hazard modelling was used to determine independent factors associated with graft failure.
Results: Of the 188 included patients, 56.4% were male, median age was 3.0 years (IQR 0.6, 10.2) and 46.3% had congenital heart disease. Most patients (75.5%) received grafts preserved with a modified de Nido solution. IT was evenly distributed amongst the cohort (37.2% vs 31.4% vs 31.4%). There were no significant differences with the baseline donor and recipient characteristics between the IT groups, except for recipient age, where those with an IT < 4.5h were older that the other groups [7.1years (0.5, 13.9) vs 3.5 (0.7, 8.2) vs 2.1 (0.5, 5.2), p< 0.001]. There were no differences in rates of early post-HTx morbidity (Table 1), specifically in the rates of primary graft dysfunction (2.9% vs 1.7% vs 5.3% p=0.5), or difference in survival free from death or re-transplant (Figure 1). In Cox proportional hazards modelling, compared to IT < 4.5h, longer IT was not associated with graft failure [IT 4.5–6: HR 1.10 (0.50–2.39), p=0.810] and [IT >6hr: HR 1.10 (0.52–2.35), p=0.797].
Conclusion: In this single center study, IT was not an independent risk factor for early post-HTx morbidity or long-term graft survival. Strategies such as use of a modified del Nido preservation solution and experience with prolonged IT donors may have contributed to our outcomes.
