Prognosis after heart transplantationBMJ 2003; 326 doi: https://doi.org/10.1136/bmj.326.7388.509 (Published 08 March 2003) Cite this as: BMJ 2003;326:509
Transplants alone cannot be the solution for end stage heart failure
- Ani Anyanwu, specialist registrar,
- Tom Treasure, professor of cardiothoracic surgery ()
Heart transplantation is in its third decade as a widely accepted treatment for advanced heart failure. What is its prognosis? In the early era of heart transplantation, the perceived alternative to transplantation was imminent death. In 1968, at the beginning of heart transplantation, Peter Medawar, the eminent zoologist and Nobel laureate whose work on tolerance set the scene for successful transplantation, correctly predicted: “The transplantation of human organs will be assimilated into ordinary clinical practice … and there is no need to be philosophical about it. This will come about for the single and sufficient reason that people are so constituted that they would rather be alive than dead.”1
Heart transplantation has a high early mortality—15-20% of recipients die within a year of the operation. 2 3 Thereafter the death rate is constant, at about 4% a year for the next 18 years, so that 50% of patients can expect to be alive after 10 years and 15% after 20 years. Application of heart transplantation has been based almost entirely on doctors' judgment in a non-investigational clinical setting. No prospective comparative studies have evaluated its effectiveness. For this reason, practically all data to guide prognosis arise from case series and registries. The registry of the International Society for Heart and Lung Transplantation has collected data on over 60 000 heart transplants performed worldwide over the past two decades and provides the largest source of such data.2
Predictors of poorer survival in recipients of heart transplants include increasing age, coming to surgery already on mechanical cardiac support or on a ventilator, and high pulmonary vascular resistance. Another major variable, without parallel in other forms of implant surgery, is a marked variation in quality of the implant—the donor heart. Age of the donor, sex, prior need for inotropic support, and duration of graft ischaemia all have an impact on the quality of the donor heart and therefore on survival of the recipient. At the time of deciding if a patient should be listed for transplantation these donor factors cannot be known. Thus a 20 year old man with dilated cardiomyopathy, who opts for transplantation expecting a longer life, may get less than hoped for if his new heart were to come from a 50 year old female donor in a hospital four hours away who is being treated with inotropes.4 Predicting prognosis before transplantation is difficult because of this heterogeneity of donors and also variations in the selection of recipients and donors, and unique immunological interactions between donor and recipient.
Transplantation is effective in relieving the symptoms of heart failure. Over 90% of survivors are in New York Heart Association class I or II and report minimal limitation in activity. 2 3 Survivors report good quality of life through the post-transplant period, with a decline in the months preceding death. However, these are people who are glad to be alive, and we know from other beneficiaries of cardiac surgery that they make great adjustments to their expectations.5 They never regain full health as the immunological effects of the donor heart and requirement for immunosuppression introduce new sources of illness. Patients require regular hospital surveillance and often repeat admission to hospital. By the sixth year after transplantation, most patients are hyperlipidaemic, about a third have abnormal renal function, a third will have transplant coronary artery disease, and a fifth would have experienced malignancy (mainly skin cancer or lymphoma).1
The options for the potential transplant recipient, however, have changed. Data from recent trials of angiotensin converting enzyme inhibitors in advanced heart failure indicate that up to 90% of patients are alive a year after starting treatment.6 Furthermore, surgical alternatives to transplantation, such as implantable ventricular assist devices, are being developed. Therefore, whereas 20 years ago death was a near certainty without a transplant, and any length of survival after heart transplantation was regarded as a bonus, in the present era some patients potentially have a similar prognosis with alternative treatments.
Medawar was less optimistic about other developments of the 20th century, which he compared to the dinosaur or the zeppelin.7 Both, he argued, were impressive in their time but each was ultimately a “cul de sac” in terms of evolution and development. For the dinosaur and the zeppelin it was the end of the road. Progress took another route. Will the same be true of transplantation of the human heart? Transplant related activity is declining and is likely to continue to do so.8 It is by its nature always going to be capped by the limited availability of suitable donors. Human donor heart transplantation cannot increase sufficiently in number to have an impact on loss of life and health due to heart failure. Both in numbers and in efficacy it has plateaued—registry data show no substantial improvement in the past decade.1 Although heart transplantation currently offers unparalleled symptomatic relief and restoration of quality of life, because only a privileged minority receive transplants, transplantation alone cannot solve the increasing public health problem of end stage heart failure. The future probably lies in further development of alternative treatments—time will tell whether these will eventually eclipse transplantation of the human heart.
Competing interests None declared.