Intraoperative anti-A/B immunoadsorption (ABO-IA) was recently introduced for ABO-incompatible heart transplantation. Here we report the first case series of patients transplanted with ABO-IA, and compare outcomes with those undergoing plasma exchange facilitated ABO-incompatible heart transplantation (ABO-PE).
Data were retrospectively analysed on all ABO-incompatible heart transplants undertaken at a single centre between January 1, 2000 and June 1, 2020. Data included all routine laboratory tests, demographics and pre- operative characteristics, intraoperative details and post-operative outcomes. Primary outcome measures were volume of blood product transfusions, maximum post-transplant isohaemagglutinin titres, occurrence of rejection and graft survival. Secondary outcome measures were length of intensive care and hospital stay. Demographic and survival data were also obtained for ABO-compatible transplants during the same time period for comparison.
Thirty-seven patients underwent ABO-incompatible heart transplantation, with 27 (73%) using ABO-PE and 10 (27%) using ABO-IA. ABO-IA patients were significantly older than ABO-PE patients (p < 0.001) and the total volume of blood products transfused during the hospital admission was significantly lower (164 [126-212] ml/kg vs 323 [268-379] ml/kg, p < 0.001). No significant differences were noted between methods in either pre or post- transplant maximum isohaemagglutinin titres, incidence of rejection, length of intensive care or total hospital stay. Survival comparison showed no significant difference between antibody reduction methods, or indeed ABO- compatible transplants (p = 0.6).
This novel technique appears to allow a significantly older population than typical to undergo ABO- incompatible heart transplantation, as well as significantly reducing blood product utilization. Furthermore, intraoperative anti-A/B immunoadsorption does not demonstrate increased early post-transplant isohaemagglutinin accumulation or rates of rejection compared to ABO-PE. Early survival is equivalent between ABO-IA, ABO-PE and ABO-compatible heart transplantation.
Richard gained his Doctorate in cardiopulmonary bypass related neurological and renal injury from the University of Southampton. He is currently a British Heart Foundation Postdoctoral Research Fellow studying novel methods for facilitating paediatric heart transplantation, and is also Senior Paediatric Perfusionist and Clinical Lead for the Digital Research Environment at Great Ormond Street Hospital. Richard sits on the Editorial Board of Perfusion and earlier this year set up the Perfusion Academic Network to promote clinical academic careers in Perfusion. He has authored over 30 research articles and won multiple awards for these and oral presentations at conferences across the globe.