Increasing the Donor Pool for Young Children Waiting for Heart Transplants

Increasing the Donor Pool for Young Children Waiting for Heart Transplants 150 150 Pam Georgiana

The one-year survival rate following a pediatric heart transplant is over 90%, However, waitlist mortality in the United States for children remains high at 17%.

Young and highly sensitized children typically experience longer waitlist times for a heart transplant, which increases their waitlist mortality. In response, doctors utilize various strategies to potentially increase the number of eligible donors and the likelihood of successful transplantation for these patients.

“ABO-incompatible heart transplantation has recently been expanded to include all pediatric transplant patients. Our goal was to find the best strategies to increase the donor pool and decrease the waitlist time for these patients,” says Emily Hayes, MD, cardiologist in the Heart Transplant and Heart Failure Program in The Heart Center at Nationwide Children’s.

The most common strategies involve plasmapheresis – the removal, treatment, and return of blood plasma from the body. This procedure removes harmful substances from plasma, such as antibodies that cause transplant rejection. However, limited data exists comparing plasmapheresis techniques for removing isohemagglutinin titers (IT), which cause red blood cell clumping, and human leukocyte antigen (HLA) antibodies, which affect immune responses.

In a study recently published in Journal of ExtraCorporeal Technology, Dr. Hayes and her colleagues at Nationwide Children’s tested two types of plasmapheresis to find out which were most effective in reducing IT and HLA antibodies. They also wanted to measure the time required for removal. This is important because patients with certain antibody levels could be eligible for ABO-incompatible heart transplantation, which involves heart transplants from donors who do not match the patient’s blood type.

The team set up four external plasmapheresis circuits, two membrane-based and two centrifuge-based. They used high-titer, highly sensitized type O donor whole blood for the test. The blood was tested in 30-minute increments for two hours, which simulated the typical transplant time. They then compared the results to baseline IT and anti-HLA antibodies.

The study found that all tests quickly and effectively reduced IT and anti-HLA antibodies in the blood. However, the centrifuge-based method showed slightly greater efficiency, particularly in HLA antibody removal. Both demonstrated similar hemolytic and thrombotic profiles. The authors stress that further study is necessary to verify these results in vivo.

“This study was a great start in learning how we can support young patients, especially those with higher sensitization, and potentially decrease their risk of rejection following transplant,” Dr. Hayes says.




  1. Colvin M, Smith JM, Hadley N, et al. OPTN/SRTR 2018 annual data report: heart. Am J Transplant. 2020;20 Suppl s1:340–426.
  2. Almond CSD, Thiagarajan RR, Piercey GE, et al. Waiting list mortality among children listed for heart transplantation in the United States. Circulation. 2009;119(5):717–727.
  3. Hayes EA, Walczak AB, Goodhue Meyer E, et al. An in vitro comparison of intra-operative isohemagglutinin and human leukocyte antigen removal techniques in pediatric heart transplantation. J Extra Corpor Technol. 2023;55(4):189-193. doi:10.1051/ject/2023034

About the author

Pam Georgiana is a brand marketing professional and writer located in Bexley, Ohio. She believes that words bind us together as humans and that the best stories remind us of our humanity. She specialized in telling engaging stories for healthcare, B2B services, and nonprofits using classic storytelling techniques. Pam has earned an MBA in Marketing from Capital University in Columbus, Ohio.