Projected survival benefit as criterion for listing and organ allocation in heart transplantation.
BACKGROUND
Current policies for the selection of candidates and the allocation of hearts for transplantation give priority to patients at greatest risk if not transplanted. However, to achieve best use of the donated organs, it is necessary to estimate the net benefit associated with transplantation.


METHODS
The survival benefit associated with being listed or not, with being transplanted or left on the waiting list, or with being transplanted or being denied the opportunity for a transplant can be estimated by means of time-to-event modeling of competing risks with intervening states. The data were obtained from the Organ Procurement and Transplantation Network and describe the outcomes of listings from 1997 to June 1999. Our analyses assessed 9,059 heart transplantation candidates, who were followed for at least 1 and up to 2 years after listing.


RESULTS
The probability of receiving a heart transplant does not increase with the probability of death while awaiting the transplant. It is comparable in the second and tenth deciles of risk (measured by the probability of death while awaiting a transplant) at 1 month after listing (15% vs 18%), but is considerably higher in the second decile at 6 months (53% vs 38%) and increasingly more so thereafter. The estimate of survival benefit stabilizes within 1 year of follow-up. Through the fourth decile of risk, the benefit of being placed on the waiting list is negligible at best, but becomes substantial (10%) for patients in the highest 2 deciles. Heart transplantation may reduce survival in the least ill patients but is clearly strongly beneficial for severely ill patients, offering reductions of 20 to 35 percentage points in probability of death when compared with remaining on the waiting list or not receiving a transplant at all.


CONCLUSIONS
Our analyses indicate that criteria other than severity of illness as measured by the probability of death are, in practice, dominant in the allocation of donated hearts for transplantation. High percentages of patients listed as well as those transplanted are not expected to undergo a substantial increase in probability of survival, and some are likely to be harmed. A survival benefit is anticipated only for severely ill patients. Estimation of the projected survival benefit of listing and of transplantation is feasible and may be used to prioritize patients and lead to the best use of donated organs.
Krakauer
Henry
H
Division of Transplantation, OSP, HRSA, DHHS, Bethesda, Maryland 20814, USA.
Lin
Monica Jia-Yeong
MJ
Bailey
R Clifton
RC
D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality* / Q000601:surgery*; D016027:Heart Transplantation; D006801:Humans; D015233:Models, Statistical; D018579:Patient Selection; D011379:Prognosis; D020379:Risk Adjustment; D012720:Severity of Illness Index; D016019:Survival Analysis; D013997:Time Factors; D014850:Waiting Lists