Does heart transplantation confer survival benefit in all risk groups?
BACKGROUND
Over 50,000 heart transplants have been performed in the last 3 decades. The global shortage of donor organs and the relaxation of candidate selection criteria over time has resulted in recent controversy about the benefits of heart transplantation for some risk groups. We assessed the survival benefit acquired in the Papworth Hospital heart transplant population overall, taking into account resuscitated marginal donors and high-risk recipients.


METHODS
All heart transplant patients listed between 1979 and June 2002 were analyzed (n = 1,212). Of these, 931 cardiac transplantations were done, including the use of 126 marginal donors. High-risk recipients (n = 163) were defined as patients being in the hospital, on intravenous inotropic drugs, and/or with a high transpulmonary gradient (>15 mm Hg). Using Cox regression with transplantation as a time-dependent covariate, we assessed the survival benefit of transplantation. In our model we assumed that after transplantation the initial risk of death is high relative to continued waiting, followed by an exponential decline in risk. The crossover point (COP) is the time at which the risk of death after transplantation is equal to that of continued waiting (i.e., the relative risk is 1). The equity point (EP) determines the time at which the early post-operative risk is offset by the later period of lower risk and, therefore, the time at which transplantation has a survival advantage.


RESULTS
Overall, the COP was at 54 days and EP at 141 days. In the marginal donor sub-group, COP was achieved at 32 days with EP at 72 days, indicating a survival benefit. The difference in the COP and EP between the borderline donor and normal donor sub-groups was not statistically significant. Post-transplant survival was not significantly different from recipients of normal cardiac allografts (p = .43). Likewise, for the high-risk recipient group, the COP and EP were at 72 and 203 days. Although post-op survival was significantly shorter than the normal-risk group, both groups achieved survival benefits.


CONCLUSIONS
Heart transplantation provides survival benefit in these risk groups of recipients in our population. This is a reflection of our active donor management protocol and rigorous donor and recipient selection process.
Luckraz
Heyman
H
The Transplant Unit, Papworth Hospital, Cambridge, United Kingdom. HeymanLuckraz@aol.com
Sharples
Linda D
LD
Charman
Susan C
SC
Tsui
Steven S L
SS
Wallwork
John
J
Parameshwar
Jayan
J
Large
Stephen R
SR
D006333:Heart Failure / Q000401:mortality* / Q000601:surgery; D016027:Heart Transplantation / Q000401:mortality*; D006801:Humans; D008017:Life Expectancy; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012306:Risk; D016019:Survival Analysis; D016896:Treatment Outcome