Indications for cardiac transplantation.

The prognosis of patients with end stage cardiac failure is poor. It can be improved by medical treatment, for example by adding vasodilators' or angiotensin converting enzyme inhibitors2 to diuretic treatment. None the less, the survival rate at 12 months in a group treated with enalapril was only 53%.2 At Papworth Hospital the cumulative survival rate for patients treated with "triple" immunosuppressive therapy (cyclosporin, azathioprine, and prednisolone) after cardiac transplantation was about 90% at 1 year and 80% at 3 years, which is similar to the experience world wide.3 Clearly, the quality of life as well as its duration must be considered. This has been shown to be substantially improved by cardiac transplantation, which has a good cost/benefit ratio.4 The major causes of mortality in the first year after transplantation are acute graft rejection and uncontrolled infection. After the first year, coronary occlusive disease is the commonest cause of mortality. Advanced occlusive disease, which tends to be diffuse and affects the proximal and distal coronary arteries, may lead to a repeat transplantation being considered. Cardiac transplantation will continue to be restricted by the limited supply of donor organs.5 In 1988, around 2500 cardiac transplants were performed in almost 250 international centres; this was only a small proportion of the total population of patients with end stage cardiac failure. How should we decide which patients should receive the available organs? On the basis of clinical findings and the results of non-invasive and invasive investigations it is usually obvious which patients are severely disabled by left or right ventricular failure or both. The first question is: "is it likely that this patient would return to normal or nearnormal activities if their heart was replaced?" Clearly, the procedure is not appropriate if the patient has severe coexisting cerebrovascular disease, peripheral vascular disease, pulmonary disease, or renal disease. In some patients, however, combined organ transplantation may be the preferred option-for example, heart and kidney or heart and liver. Patients accepted for cardiac transplantation should be well motivated and able to cope with immunosuppressive treatment after operation and also the inconvenience of repeated endomyocardial biopsy, particularly in the early postoperative period. In many transplant centres the upper age limit for the recipient is between 55 years and 60 years. Biological age as well as chronological age should be considered. The age range for recipients of cardiac transplants world wide is 1 day to 78 years and in our unit it is 6 to 63 years.3 At Papworth Hospital the age limit is around 55 years for the patients with coronary artery disease and around 60 years for those with dilated cardiomyopathy. This is because in the early postoperative period vascular complications, particularly cerebrovascular events and gastrointestinal ischaemia, are more common in the more elderly patients with coronary artery disease. Most of our patients undergoing cardiac transplantation had heart failure refractory to medical treatment associated with either coronary artery disease (53%) or dilated cardiomyopathy (44%). This resembles experience world wide-43% and 49% respectively.3 The timing of cardiac transplantation may be difficult in some patients. The symptoms of cardiac decompensation in patients with coronary artery disease usually remain stable, unless there is an event causing further myocardial damage, and sudden death is a continuing risk. In contrast, the condition of those with dilated cardiomyopathy can deteriorate quite rapidly, or in some cases improve, making their assessment for cardiac transplantation and the timing of surgery even more difficult. Therefore, careful and frequent follow up is required for each patient. The remaining group of patients undergoing transplantation-in our series, 3% of the total population-includes those with other types of cardiomyopathy (for example, hypertrophic or restrictive), end stage valve disease, severe angina caused by coronary artery disease that is not amenable to revascularisation, and patients with ventricular tachycardia that is refractory to other forms of treatment. Occasionally, therefore, it may be appropriate to give a cardiac transplant to a patient who is severely limited by angina rather than by the symptoms of cardiac failure-if they are unsuitable for coronary angioplasty or bypass surgery. Patients with ventricular tachycardia that is refractory to drug treatment, many of whom have considerable left ventricular dysfunction, are an interesting group. Transplantation should be considered in those who are severely restricted by symptoms of cardiac failure. For those with life threatening tachycardia but no cardiac failure the relative cost/benefit of implantable cardioverter-defibrillators and Papworth Hospital, Cambridge PM Schofield