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The results of corrective surgery in 32 patients with transposition of the great arteries (TGA) are reviewed. Patients with TGA and associated defects comprised 47% of the series. The over-all long-term mortality rate was 31%. An acceptable mortality rate of 17,5% was achieved in simple TGA by using a Mustard repair. Good results were obtained with the Rastelli operation for patients with TGA, ventricular septal defect and severe pulmonary stenosis. Results were poor in patients with TGA and unrestricted ventricular septal defects, in whom palliative pulmonary artery banding or corrective surgery under 6 months of age is advocated. The major late complication was patch contraction resulting in pulmonary or systemic venous obstruction.

The autopsy findings in a White man aged 59 years are presented; he underwent heterotopic cardiac transplantation with left ventricular bypass for irreversible left ventricular failure caused by severe ischaemic heart disease. Microscopically, the donor heart showed mild signs of chronic rejection with negligible loss of functional myocardium, and no complications attributable to the surgical technique. Severe, generalised atherosclerosis had resulted in fibrous replacement of the recipient left ventricular myocardium and intra-operative atheromatous embolisation to the brain, the latter being the main contributory factor in the patient's death. Other significant findings were bilateral femoral vein thrombosis with recurrent pulmonary infarction, Aspergillus granulomata of the right lung, cytomegalovirus infection of lungs and oesophagus, Herpes simplex infection of the tongue and oesophagus, and duodenal ulceration with haemorrhage.

The removal of the patient's own diseased heart in order to perform a total cardiac transplantation has several disadvantages. A new technique for bypassing the patient's diseased left ventricle by using a cardiac allograft has been developed in our laboratory and applied clinically in 2 patients. This technique carried no direct surgical mortality, and no complications resulting from the patient's own heart being left in situ have been observed thus far. The presence of a second heart lying partly in the anterior mediastinum and partly in the right pleural space appeared to have no deleterious effects. Several advantages over the conventional transplant have been noted and are discussed.

Untreated coarctation of the aorta in infants is associated with a high mortality, reaching up to 90%. During a period of 7 years 26 infants underwent surgical repair of this condition, the youngest being 6 days old and the oldest 11 months. Two underwent emergency surgery after catheterization, while the rest had an elective or semi-elective operation. Associated anomalies were present in 85% of the whole group; of the 22 patients with anomalies, a ventricular septal defect (VSD) and patent ductus arteriosus (PDA) were present in 11 patients, a PDA in 7, a VSD in 6, transposition of the great arteries in 3, an atrial septal defect in 3, a single ventricle in 1, a hypoplastic aortic arch in 1, a hypoplastic left ventricle in 1 and a partial anomalous pulmonary venous defect in 1. Four patients (15%) had no other associated anomaly. The surgical techniques used were coarctectomy and end-to-end anastomosis in 61,5%, subclavian flap aortoplasty in 27%, and Dacron patch aortoplasty in 11,5%. Additional pulmonary artery banding was performed in 6 patients; in 2 patients lung biopsies were also carried out in order to establish the severity of pulmonary hypertension. The overall hospital mortality was 30,7%. No patients with uncomplicated coarctation died.

This is a review of the results of surgical treatment of congenital heart disease in children aged less than 12 years over the period 1975 - 1981 (1254 cases). The patients are divided into two groups, those treated between 1975 and 1979 (903 cases) and those treated in 1980 and 1981 (351 cases). Only 19,7% of the patients in the first group were under the age of 1 year, but 26,5% in the second group were in this age group. This reflects a change in policy and an attempt at surgical correction at a much younger age than was previously the case. Our present policy in cardiac emergencies in infants will be discussed. Despite the higher percentage of infants aged under 1 year who were treated in 1980 - 1981, the mortality rate was lower than that for the period 1975 - 1979. This probably reflects greater experience in the post-operative management of patients under the age of 1 year.

Heart transplantation still remains the only form of treatment for patients suffering from terminal heart failure as the result of diffuse myocardial disease. The lack of enthusiasm for this operation has no scientific or moral basis. Our own limited experience and the much wider experience of other workers in this field show that with proper patient and donor selection and careful postoperative management, the results of this operation compare very favourably with those of any transplantation of other organs and in the surgical treatment of other types of terminal diseases.

The Fontan procedure was applied to correct 13 cases of tricuspid atresia, all with concordant arterial connections. Seven of the patients had had a total of ten previous operations to create palliative shunts. There were 3 early deaths, all due to low cardiac output states, but no late deaths. The postoperative management of the survivors was not unduly complicated, except in the 1st patient. Complete heart block developed transiently in 2 patients. The results are classified as good to very good in all 10 survivors. Our experience supports the opinion that the Fontan procedure gives good symptomatic relief in patients with tricuspid atresia. We discuss the possibility of improving long-term left ventricular function by early complete correction.

A shortage of donors remains the major limiting factor as regards the number of kidney and heart transplants performed in South Africa each year. The medical, legal and administrative aspects of cadaveric organ donation in this country are reviewed. The pathophysiology of brain death and the criteria necessary for a definite diagnosis are described, together with the criteria for the selection of cadaveric organ donors. The statutory requirements pertaining to the removal of human hearts and kidneys for the purposes of transplantation are detailed. The subsequent management of the brain-dead donor up to the time of excision of the required organ is described, and a note regarding the preservation and transportation of the donor organs is added.

The morhpological changes in 49 chacma baboons after cardiac transplantation were studied by light and electron microscopy. Non-immunosuppressed grafts were tolerated for an average of 10 days and immunosuppressed grafts for 18 days. Serial biopsy specimens of non-immunosuppressed grafts showed a progression in severity of rejection changes. Electron microscopy mirrored the light microscopic changes. Rejection changes in the baboon appear similar to those encountered in human and canine allografts. Heterotopic transplants showed more severe grades of rejection than would be compatible with life in orthotopic transplants.

Tetralogy of Fallot consists essentially of two abnormalities: a large, unrestrictive ventricular septal defect and severe obstruction to the outflow of the right ventricle. A clear understanding of the principles described in this article should result in a mortality of under 5% after complete correction of tetralogy of Fallot.

Primary heart tumours are extremely rare. Over a period of 25 years 22 primary cardiac tumours were diagnosed clinically or at autopsy at Groote Schuur Hospital. Fourteen patients with myxomas, 1 with lymphocytic lymphoma and 2 with haemangiomas underwent surgery. A further 4 myxomas and 1 histiocytoma were found at autopsy. In both the cases of haemangioma the diagnosis of a vascular tumour was made before surgery. One tumour had infiltrated the lateral wall of the left ventricle and was unresectable; only a biopsy specimen was taken. The patient, however, remains well some 6 years later. In the second patient the haemangioma was situated in the outflow tract of the right ventricle and was successfully excised. The clinical history, pathological features and management of both cases are presented.

A system has been developed for the ex vivo functional testing of isolated hearts. Three groups, each of 10 pig hearts, have been studied: group 1--freshly excised hearts; group 2--heart hypothermically perfused for 20 - 24 hours with Krebs-Henseleit solution; group 3--hearts similarly perfused with a clear fluid hyperosmolar solution. Group 2 hearts performed poorly on functional testing and would clearly have been unsuitable for transplantation. Haemodynamic observations on group 3 hearts showed little statistical difference from those of group 1, suggesting good preservation. The value of the ex vivo testing system as a reliable means of assessing myocardial function is discussed, and has been confirmed by subsequent successful orthotopic transplantation of baboon hearts stored under identical conditions.

In the 2-year period 1979-1980, 34 patients were assessed at Groote Schuur Hospital as candidates for heterotopic heart transplantation. Ischaemic heart disease was the most common underlying cause (19 patients), with cardiomyopathy (9), rheumatic heart disease (2), failed transplants (3), and endomyocardial fibrosis (1) as the other causes of myocardial disease. Five patients were not accepted into the transplant programme, 2 declined after being accepted, and in 3 the initial decision of acceptance was later reversed. Nine patients died while awaiting suitable donors, the mean survival time from the date of acceptance being only 26 days. Fifteen patients underwent heterotopic heart transplantation, 11 remaining alive at the end of the period of study; 8 had normally functioning donor hearts but 3 had suffered irreversible rejection and awaited a second transplant.

Between 1 August 1975 and 31 October 1982, 76 patients aged between 70 and 82 years (mean 73,4 years) underwent elective (71) or emergency (5) valve replacements. Fifty patients underwent aortic valve replacement (including 5 with additional coronary artery bypass grafts), 19 mitral valve replacement including 3 with coronary artery bypass grafts, and 7 double valve replacements. There were 3 early deaths (3,9%) and 9 late deaths (11,8%) during the follow-up periods of 1 month - 86 months (mean 29 months). Actuarial analysis showed a survival rate of 95% at 1 year, 89% at 2 years, and 77% at 5 years. The clinical result of operation was judged to be good or excellent in all patients except one. It is concluded that valve replacement in patients over 70 years carries a low operative risk, statistically similar to that for younger patients at our institution, and is accompanied by a satisfactory result.

A review has been undertaken of the number and types of surgical procedures performed in the Department of Cardiac Surgery of the University of Cape Town during the 11-year period 1971-1981, together with data on associated mortality. A yearly average of 560 operations was carried out, of which 75% were for acquired and 25% for congenital heart disease. The number of patients treated continues to rise, from 434 in 1971 to 690 in 1981. There has been a slight reduction in the overall average yearly mortality, from 6.1% between 1971 and 1975 to 5.0% between 1976 and 1981. There was a significant increase in the number of valve replacements in 1975 and 1976 and a more recent, continuing increase in operations for ischaemic heart disease, which now form 19% of the total operations. In both these groups the average yearly mortality has fallen during the period of study. The number of operations each year for congenital heart disease has remained fairly constant, but, disappointingly, there has been no significant reduction in mortality.

Between November 1974 and February 1982 40 patients underwent heterotopic heart transplantation at Groote Schuur Hospital, Cape Town. In 4 of these patients retransplantation was carried out, bringing the total number of heterotopic heart transplant operations to 44. Fourteen patients are alive to date, from 4 months to more than 7 years after transplantation. The 1-year survival rate has been 60%. Three of the first 6 patients in this series have survived for 6 years or more, while 6 of the 7 patients who received transplants during 1981 (including 2 who underwent retransplantation) are alive. Retransplantation of the donor heart, donor heart procurement from distant sources using prolonged myocardial preservation techniques and the reasons why heterotopic cardiac transplantation is more advantageous than other methods are discussed. The surgical technique and some modifications introduced since this method was first described in 1975 are presented in detail.

Over a period of 11 years, commencing in December 1967, 31 cardiac transplants, 10 orthotopic and 21 heterotopic, were performed at Groote Schuur Hospital. Two patients with orthotopic transplants have a long survival, 1 for 7 1/2 and 1 for 9 1/2 years, and 1 with a heterotopic transplant for 4 years. Eighteen patients have died, and autopsy was performed from 13 to 623 days postoperatively. Rejection of the donor heart was found in 61,1% and was the cause of death in 44,4% of cases. Infection, attributable to immunosuppression, was a common finding and consisted of extensive pneumonia, usually due to Klebsiella aerogenes and Pseudomonas aeruginosa (38,8%), herpesvirus infection (38,8%), cytomegalic virus infection (37,5%), aspergillosis and other opportunistic infections. A combination of cardiac rejection and infection accounted for most of the deaths. The cardinal microscopic features of acute rejection were interstitial lymphocytic infiltration and myocytolysis, while chronic rejection was typified by obliterative myo-intimal proliferation of coronary arteries, with concurrent lipid deposition in the major coronary arteries. These lesions resembled atherosclerosis and caused graft failure due to myocardial ischaemia. Ultrastructurally, severe myofibre damage was reflected in extensive loss of cytoplasmic myofilaments. The advantages of heterotopic over orthotopic transplantation are discussed.

The technique of surface-induced hypothermia, circulatory arrest and limited extracorporeal circulation was used in the surgical correction of congenital heart defects in 125 young children. Hospital mortality was 18% and no death could be attributed to the surgical technique. An analysis of risk factors demonstrated that successful corrective surgery was not significantly related to age, body weight or pulmonary vascular obstructive disease. In transposition of the great arteries, the presence of a ventricular septal defect was associated with an increased mortality. Emergency operations performed because of severe hypoxaemia carried a high mortality, especially in patients with tetralogy of Fallot.

One of the indications for the use of the heterotopic cardiac transplant is temporarily to support a failing heart in the anticipation of its recovery when all other measures of support have been unsuccessful. Human donors are not always available when required and we decided to use a xenograft for this purpose when the need arose. This report details our experience with a baboon and a chimpanzee cardiac xenograft transplant in the heterotopic position. We have found (a) that the operation is technically feasible; (b) that the xenograft will support the failing circulation, but that the more support required, the bigger the xenograft should be and the species chosen accordingly; (c) that severe acute rejection will occur within 4 days and the procedure should therefore only be employed where there is evidence that the patient's own heart function will recover rapidly.

Between January 1974 and December 1981, 80 patients aged between 1 and 13 years underwent surgical correction of coarctation of the aorta. At pre-operative examination 45 patients had absent femoral pulses (group A) and 35 had palpable femoral pulses (group B). Nineteen patients were lost to late follow-up; the remaining 61 (76%) were followed up for between 3 months and 7 years. Of the patients in group A 89% had systolic and 87% diastolic hypertension, while in group B the respective figures were 80% and 77%. At follow-up after surgery, systolic hypertension was present in 36% of patients in group A and in 16% of those in group B. Diastolic hypertension was present in 73% of patients in group A but only in 19% of those in group B (P less than 0,0001). It would appear that children with coarctation of the aorta and absent femoral pulses are more likely to continue to have diastolic hypertension after surgical correction of the anomaly than are children in whom the femoral pulses are palpable. Early operation might reduce the incidence of hypertension in this group.

Radionuclide scanning of the donor left ventricle using technetium-99m-labelled red cells was used to monitor acute rejection after heterotopic heart transplantation and compared with histopathological evidence of rejection obtained at examination of an endomyocardial biopsy specimen. The ejection fraction and end-diastolic, end-systolic and stroke volumes were calculated at each examination; an equation was derived from these data to predict the degree of acute rejection, using histopathological examination of endomyocardial biopsy specimens as criteria of the presence and severity of rejection. A highly significant multiple correlation between radionuclide scanning parameters and endomyocardial biopsy was found. The advantages of non-invasive radionuclide scanning over the invasive procedure of endomyocardial biopsy are discussed.