Dr. Chau Mo Chee, Elaine
April 2007
In Hong Kong the first heart transplant operation was performed at Grantham Hospital in December 1992. At more than fourteen years after the operation, this first heart transplant recipient is leading a normal and active life. Since then until December 2006, a total of 77 patients have undergone this life-saving operation. Two other patients had received combined heart and lung transplantation. Over the past few years, the number of heart transplants done per year is between and 7 and 12, except in year 2003 when only 5 heart transplants were done because of SARS. Like other parts of the world, scarcity of suitable donors remains the major limiting factor in expansion of the heart transplant program in Hong Kong.
In contrast to western countries, where ischaemic heart disease is the major cause for end-stage heart failure, in Hong Kong dilated cardiomyopathy and valvular heart disease are the two major underlying diseases for heart transplantation. The one- and five-year survival rates after heart transplantation are 85% and 80%, respectively. Seven cases had early graft failure and died in the early post-operative period. 91% of cases were successfully discharged from hospital and the majority of the surviving patients are in good function status. Many of the heart transplant recipients have returned to normal daily activities and full-time jobs, including strenuous work such as being a policeman and a fireman!
In our transplant program, we use cyclosporine A, azathioprine and prednisolone as our basic maintenance immunosuppressive drugs. However, increasingly new immunosuppressive drugs, such as tacrolimus, mycophenolate mofetil, sirolimus and everolimus, are also used to replace cyclosporine A or azathioprine. In the past, we used OKT3 as our induction therapy but since 2002 we have used daclizumab instead with satisfactory results.
The two major complications after heart transplantation are rejection and infection. With the development and availability of the more potent immunosuppressive agents, allograft rejection with haemodynamic disturbance is now rarely seen. However, opportunistic infections are commonly seen, such as atypical tuberculosis, pneumocystis carinii, nocardiosis and reactivation of cytomegalovirus. Another complication post-heart transplant is transplant coronary artery disease, which may not be amenable to revascularization because of the diffuse nature of the disease and poor run-off of the arteries. We have also encountered five cases of malignancies, including two cases of leukaemia and one case each of lung carcinoma, glioblastoma and brain post-transplant lymphoproliferative disease. Three of them have since died from the malignancy.
Currently there are about twenty patients on the waiting list for heart transplantation. Many of these end-stage heart failure patients are in NYHA functional class III to IV despite optimal medical therapy and device therapy (such as biventricular pacemakers and implantable cardiovertor-defibrillators). The waiting time from listing to transplant is 5 months on average, with group O patients having longer waiting time than non-group O patients (7 months versus 4 months). Since 1999, we have used intra-aortic balloon counterpulsation successfully in 14 cases as bridge to transplantation and the record duration of using an intra-aortic balloon pump for this purpose was four months! Ventricular assist devices which provide a more reliable mechanical circulatory support are now undergoing rapid development. It is hoped that these ventricular assist devices will be available locally soon, not only as bridge to transplant but as destination therapy for end-stage heart failure as an alternative to heart transplant.
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