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Updated: Oct 23, 2025

A High-Fidelity Porcine Model of Orthotopic Heart Transplantation Following Donation after Circulatory Death
Published on: June 6, 2025
Decline of increased risk donor offers increases waitlist mortality in paediatric heart transplantation
Jordan E Ezekian1, Michael S Mulvihill2, Brian Ezekian2
1Department of Pediatrics, Division of Pediatric Cardiology, The Hospital for Sick Children, Toronto, Canada.
Insights
Declining increased risk donor offers for pediatric heart transplants significantly increases mortality risk. Accepting these offers improves survival rates, offering a strategy to reduce waitlist deaths.
Area of Science:
- Cardiology
- Transplant Surgery
- Public Health
Background:
- Increased risk donors (IRDs) in pediatric heart transplantation pose potential infectious disease risks despite testing.
- Refusing IRD offers may elevate waitlist mortality, but the transmission risk is low.
Purpose of the Study:
- To evaluate the risks associated with declining an initial increased risk donor organ offer in pediatric heart transplantation.
- To determine the survival benefit of accepting initial IRD organ offers.
Main Methods:
- Retrospective analysis of pediatric heart transplant candidates using 2007-2017 United Network of Organ Sharing data.
- Competing risks analysis and stratified Cox regression to assess mortality risk and survival benefit.
Main Results:
- 22.3% of initial IRD offers were accepted.
- Candidates accepting IRD offers were younger, more often female, listed as status 1A, and less likely to require mechanical support.
- Accepting an IRD offer was associated with significantly lower 1-year (6% vs. 13%) and 5-year (15% vs. 25%) mortality.
- Declining an IRD offer increased mortality risk (aHR 1.87).
Conclusions:
- Acceptance of increased risk donor organs is linked to a significant survival advantage in pediatric heart transplantation.
- Increasing IRD organ acceptance can be a strategy to reduce pediatric heart transplant waitlist mortality.
Background:
Increased risk donors in paediatric heart transplantation have characteristics that may increase the risk of infectious disease transmission despite negative serologic testing. However, the risk of disease transmission is low, and refusing an IRD offer may increase waitlist mortality. We sought to determine the risks of declining an initial IRD organ offer.
Methods And Results:
We performed a retrospective analysis of candidates waitlisted for isolated PHT using 20072017 United Network of Organ Sharing datasets. Match runs identified candidates receiving IRD offers. Competing risks analysis was used to determine mortality risk for those that declined an initial IRD offer with stratified Cox regression to estimate the survival benefit associated with accepting initial IRD offers. Overall, 238/1067 (22.3%) initial IRD offers were accepted. Candidates accepting an IRD offer were younger (7.2 versus 9.8 years, p < 0.001), more often female (50 versus 41%, p = 0.021), more often listed status 1A (75.6 versus 61.9%, p < 0.001), and less likely to require mechanical bridge to PHT (16% versus 23%, p = 0.036). At 1- and 5-year follow-up, cumulative mortality was significantly lower for candidates who accepted compared to those that declined (6% versus 13% 1-year mortality and 15% versus 25% 5-year mortality, p = 0.0033). Decline of an IRD offer was associated with an adjusted hazard ratio for mortality of 1.87 (95% CI 1.24, 2.81, p < 0.003).
Conclusions:
IRD organ acceptance is associated with a substantial survival benefit. Increasing acceptance of IRD organs may provide a targetable opportunity to decrease waitlist mortality in PHT.
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