Multicenter experience of ABO-incompatible pediatric cardiac transplantation

Area of Science:

• Cardiology
• Immunology
• Transplantation

Background:

• ABO blood group incompatible cardiac transplantation is underutilized despite proven benefits in reducing waitlist mortality.
• Toronto is the only center with published large-scale results, limiting wider adoption.
• UK recipient selection criteria differ from US and Canadian standards.

Purpose of the Study:

• To review ABO-incompatible heart transplantation outcomes in the UK.
• To assess the feasibility of replicating Toronto's success in other centers.
• To evaluate the safety and efficacy of established isohemagglutinin production in pediatric patients.

Main Methods:

• Retrospective review of 21 pediatric ABO-incompatible cardiac transplants (February 2000 - November 2006).
• Standard immunosuppression regimens were used.
• Pre-transplant donor-specific isohemagglutinin reduction via plasma exchange for levels >1:4 (UNOS cutoff).

Main Results:

• All 21 recipients survived without retransplantation.
• No episodes of humoral rejection were observed.
• 19/21 recipients showed persistent deficiency of donor-specific isohemagglutinins post-transplant; 2/21 had detectable levels without clinical rejection.

Conclusions:

• Excellent outcomes in ABO-incompatible cardiac transplantation are replicable in other centers.
• This procedure can be safely performed in pediatric patients beyond infancy with established isohemagglutinin production.
• Preoperative antibody removal strategies are crucial for successful ABO-incompatible heart transplantation.