ABO-Incompatible Heart Transplantation Remains Underutilized Despite Comparable Outcomes in Pediatric Heart...

Area of Science:

• Pediatric Cardiology
• Transplantation Immunology
• Organ Transplantation Policy

Background:

• ABO-Incompatible (ABO-I) heart transplantation (HT) is crucial for pediatric patients facing donor shortages.
• Despite comparable outcomes, ABO-I HT is not universally adopted.
• This study analyzes ABO-I HT trends and outcomes, focusing on the 2016 United Network for Organ Sharing (UNOS) policy change.

Purpose of the Study:

• To provide a contemporary analysis of ABO-Incompatible heart transplantation in children.
• To evaluate the impact of the 2016 UNOS policy change on ABO-I HT outcomes.
• To assess the relationship between center volume and survival in pediatric ABO-I HT.

Main Methods:

• Retrospective analysis of the Organ Procurement and Transplantation Network database.
• Examined pediatric patients (≤2 years) undergoing HT in two eras defined by the 2016 UNOS policy change.
• Primary outcome: posttransplant survival; secondary outcomes: waitlist mortality, center volume-survival relationship, and postoperative complications.

Main Results:

• A total of 2,770 children underwent HT, with 493 (18%) being ABO-I recipients.
• No significant difference in waitlist mortality for ABO-I eligible candidates across eras (HR 0.70, P=.07).
• One- and five-year survival rates were similar between ABO-I and ABO-compatible (ABO-C) cohorts, and no difference in survival for ABO-I recipients between high-volume and non-high-volume centers was observed.

Conclusions:

• ABO-Incompatible heart transplantation provides outcomes comparable to ABO-compatible transplantation.
• Center volume does not impact survival rates for ABO-I HT recipients.
• The 2016 UNOS policy has not influenced waitlist mortality in this pediatric population, supporting ABO-I HT as a standard of care.