Heart transplantation has conventionally been restricted to the use of hearts acquired from donors after brain death. This is to allow for in situ evaluation of cardiac function and of the donor allograft’s potential for transplantation before surgical procurement. The use of hearts from donors after circulatory death has been further reviewed on the basis of clinical results at single sites in Australia and the United Kingdom because the demand for heart transplants considerably outweighs the supply of acceptable donor allografts. Extracorporeal machine perfusion, which allows for the resuscitation of the heart after circulatory death and examination of the heart for appropriateness for transplantation, makes it possible to preserve and evaluate potential donor hearts in situ after circulatory death. Ex situ perfusion of the heart has produced promising preliminary results that have only been observed in a small number of instances or series at a single site. However, data from clinical trials that compare hearts from brain-dead patients and hearts from circulatory dead individuals have been lacking.
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Brain-dead vs. Circulatory-dead
A randomized clinical trial called “Donors After Circulatory Death Heart Trial” was designed to ascertain whether clinical outcomes in recipients of hearts that had been revived using portable extracorporeal nonischemic perfusion after the donor’s circulatory death were non-inferior to outcomes in recipients of hearts that had been preserved and transported using conventional cold storage after the donor’s brain death.
Adult candidates in the United States who were on the waiting lists at participating transplantation centers gave written informed consent and were randomly divided into two groups: one eligible for transplant with hearts from circulatory-death donors (circulatory-death group) and the other eligible for transplant with hearts from a brain-death donor (brain-death group), in a 3:1 ratio. However, due to an unexpectedly high supply of hearts from circulatory-death donors, there were obvious distinctions between the two groups.
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The study demonstrated that 6-month patient survival for receivers of hearts from donors who died from circulatory disease was non-inferior to patient survival for recipients of hearts from donors who died from brain death. It should be noted that 89% of hearts from circulatory-death donors overall were transplanted following resuscitation and evaluation with the perfusion system. The mean number of major adverse events linked to the heart graft per patient at 30 days after transplantation did not significantly differ between groups.
Clinical significance
There was a faster turnaround time for recipients of hearts from circulatory-death patients. This factor could lead to an increased survival rate. The trial’s short-term results have been disclosed; long-term outcomes and potential late problems are not yet known. A five-year follow-up would make it possible to better understand the long-term effects of transplanting a donor heart following circulatory death.
final thoughts
The need for cardiac transplants is great and expanding globally. Up until recently, only brain-dead donors could be used for heart transplants since brain death allowed for an in-person evaluation of the heart’s viability and functionality. The trial has shown that 6-month survival following transplantation of a donor heart that had been revived and evaluated using extracorporeal nonischemic perfusion after circulatory death was non-inferior to 6-month survival following transplantation of a donor heart that had been preserved using cold storage after brain death.
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References
D’Alessandro, D. A., Schroder, J. N., Patel, C. B., DeVore, A. D., Bryner, B. S., Casalinova, S., Shah, A., Smith, J. W., Fiedler, A. G., Daneshmand, M., Silvestry, S., Geirsson, A., Pretorius, V., Joyce, D. L., Um, J. Y., Esmailian, F., Takeda, K., Mudy, K., Shudo, Y., Salerno, C. T., Pham, S. M., Goldstein, D. J., Philpott, J., Dunning, J., Lozonschi, L., Couper, G. S., Mallidi, H. R., Givertz, M. M., Pham, D. T., Shaffer, A. W., Kai, M., Quader, M. A., Absi, T., Attia, T. S., Shukrallah, B., Sun, B. C., Farr, M., Mehra, M. R., Madsen, J. C., Milano, C. A., & Milano, C. A. (2023). Transplantation Outcomes with Donor Hearts after Circulatory Death. The New England Journal of Medicine. https://doi.org/10.1056/NEJMoa2212438
