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The Fontan operation has been used to palliate patients with a functional single ventricle. In many such patients the operative risk for a Fontan procedure is high. The bidirectional cavopulmonary anastomosis (BCPA) is a useful intermediate palliative procedure before Fontan correction. It may reduce the deleterious sequelae of chronic hypoxaemia and long-term ventricular overload, thus yielding a more suitable Fontan candidate. We reviewed our experience of 9 patients with univentricular hearts who were at the time of the BCPA not considered suitable candidates for conventional Fontan operation. Two patients had double inlet right ventricle (DIRV) with pulmonary stenosis (PS) and ventricular septal defect (VSD), 2 had univentricular heart, 4 had tricuspid atresia (TA) and hypoplastic right ventricle (RV), 1 patient had atrioventricular septal defect (AVSD) with double outlet right ventricle (DORV) with hypoplastic RV. Two of the 9 patients had bilateral superior vena cavae. All except one had undergone prior palliative operations. The mean age at BCPA was 4.7 years (range 1.5 years to 6 years) and the mean weight at surgery was 15 kg (range 7 to 22 kg). There were no operative deaths. The mean hospitalization stay was 8.5 days (range 5 to 13 days) with a mean follow up of 14 months. Median oxygen saturation improved from 78.7 +/- 6.3% to 85.9 +/- 3.9%. The BCPA is a useful palliative procedure to stage Fontan type reconstruction in selected patients with univentricular hearts.

The incidence of coronary artery disease in Singapore has shown a rapid rise in recent years, however, there is a subjective impression that the prevalence of atherosclerotic peripheral artery diseases, although sharing common aetiological factors with coronary artery disease, has not shown a similar rise. We set out to determine the incidence of occlusive peripheral artery diseases of the lower limb in a selected population of Asian patients using a non-invasive test and we analysed the risk factors. The overall prevalence of peripheral artery disease of the subjects as determined by an abnormal ankle brachial index less than 0.9 in at least one limb was 19.1%. Increasing age, hypercholesterolemia and smoking were risk factors. In patients with proven coronary artery disease, abnormal ankle brachial indices were present in 21.3% of patients with angiographic evidence of coronary artery disease but in only 13.0% of those without. In this study, the incidence of peripheral artery disease in this selected Asian population was high. With the increasing availability of vascular laboratories and awareness of the diseases, we can expect to see increasing numbers of patients presenting with these problems.

We report a case of a large sclerosing haemangioma of the lung that was found incidentally on roentgenography of an asymptomatic woman presenting for routine health screening. Computed tomographic scan showed a well-defined "coin" lesion with peripheral foci of calcification. The lesion had a variegated histological appearance comprising four major patterns--solid, papillary, haemorrhagic and sclerotic. There appeared to be two populations of cells--distinct round cells with abundant clear cytoplasm constituting the solid component and uniform cuboidal cells with small, dark nuclei lining irregular spaces. Positive immunohistochemical staining for cytokeratin and epithelial membrane antigen, and the ultrastructural demonstration of epithelial characteristics and electron-dense bodies showed that the proliferating cells had features in keeping with type 2 pneumocytes. This is a benign condition and the prognosis is excellent.

The purpose of this study was to evaluate the usefulness of colour flow mapping (CFM) in the diagnosis and classification of congenital ventricular septal defect (VSD) and in the confirmation of spontaneous and surgical closure. Between August 1988 and March 1990, a total of 102 patients with isolated VSD (82 preoperative and 20 postoperative), age ranging from one day to 14 years, were subjected to 176 echocardiographic examinations. Sequential cross sectional imaging and CFM were the main modalities of assessment with conventional Doppler interrogation for quantitative measurements. In the preoperative group, there were 56 (68.3%) perimembranous (pm) VSD, 14 (17.1%) muscular (m) VSD and 12 (14.6%) doubly committed subarterial (dcsa) VSD. Ventricular septal defect was detected by CFM only in 88.9% of m/VSD, 57.6% of dcsa/VSD and 11.8% of pm/VSD (p less than 0.01). Spontaneous closure rate was highest in m/VSD (28.6%) followed by pm/VSD (8.9%) (p = 0.05). None of the dcsa/VSD closed as assessed by CFM. In the postoperative group, CFM served to quickly confirm complete closure without residual left to right shunt in 20 patients. In addition, CFM was useful in the assessment of haemodynamics and flow directed Doppler interrogation. Hence, CFM is a useful adjunct to cross sectional imaging in the assessment of children with isolated VSD.

From January 1987 to December 1989, 80 patients with carotid bruit and/or history of transient ischaemic attack/stroke underwent digital subtraction angiography (DSA) prior to consideration for coronary artery bypass graft. Thirty-eight patients (Group I) out of the 80 had coronary artery bypass graft done with postoperative stroke in five (13.2%); this contrasted with a group of 320 patients (Group II) without cerebrovascular disease who underwent coronary artery bypass graft during the same period with postoperative stroke in two cases (0.63%) (p less than 0.0005). Carotid artery stenosis was noted on the DSA in 66% of Group I patients, with significant disease (greater than 70% occlusion) in 15%, while the study was normal in 34% of cases. Combined carotid endarterectomy and coronary artery bypass graft was done in five of Group I patients, with postoperative stroke in one; this was the only one among the stroke patients with significant carotid disease. All strokes, except in one patient, resolved within one to 6 1/2 months. These results suggest that the risk of stroke after coronary artery bypass graft is increased in patients with carotid bruit or history of transient ischaemic attack/stroke and in the presence of established carotid artery disease. The place of combined carotid endarterectomy and coronary artery bypass graft in these cases remains to be determined.

Dramatic advances in heart transplantation have been made in the last decade. It is now a standard treatment option for end stage cardiac disease. There is tremendous potential for research and advances in the areas of heart transplantation, heart-lung transplantation, mechanical assist devices and the artificial heart. A few issues of current interest in heart transplantation are selected for discussion.

The amount of protamine required for the neutralisation of heparin following cardiopulmonary bypass was determined by a Protamine Titration Assay using the principle of the dose--response curve and the patient's estimated blood volume. In 300 open heart surgery patients, infusion of the determined dose of protamine normalised the Activated Clotting Time (ACT) to baseline levels in 97% of these patients and produced adequate hemostasis. Our present study showed that the dose of protamine dropped to 75% of the dose calculated by conventional method of heparin to protamine ratio of 1:1. This had minimised the adverse effects of excessive protamine administration and optimised coagulation control after extracorporeal circulation.

We found that fibreoptic bronchoscopy was a useful, simple, safe and accurate method in the diagnosis of inhalation injury, determining the type, the site and the extent of damage sustained. The most common mucosal damage was erythema and oedema of the supraglottic and glottic tissues, though in a few cases more severe and extensive injury was seen. Death seemed to be determined largely by the extent of skin burn but since there did not appear to be a close relationship between the severity of skin burn and the presence of inhalation burn, we suggest that the two types of injuries be evaluated separately. The main therapeutic role lies in the assessment and anticipation of imminent upper airway obstruction caused by oedema of the supraglottic tissues and the glottis. Endotracheal intubation could then be carried out promptly. Changes in clinical features and laboratory results were too slow to be of use in the prediction of upper airway obstruction, but could be indirect indicators of lower and peripheral airway injury.

The Singapore experience with 11 cases of sclerosing haemangioma of lung seen from 1970-1984 is analysed. There is female preponderance (9/11) and the majority (8/11) were asymptomatic. Seven patients were treated by wedge resection and 4 had lobectomies. Microscopically, the lesion had variegated growth pattern with characteristic polygonal cells present in the stroma. All patients were well after surgery. The longest follow-up period is 7 years with no recurrence seen. This is an unusual, distinctive and benign entity which should be distinguished from other inflammatory conditions in the lung.