Pregnancy and mitral valve prosthesis

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Serum transaminase levels following cross-clamping of the aorta in open heart surgery without coronary artery perfusion

A study was carried out on 25 patients who underwent open heart surgery, with cross-clamping of the aorta but without perfusion of the coronary arteries to ascertain whether this produced any adverse effect on the myocardium. Serum enzyme levels (glutamic oxalacetic transaminase and glutamic pyruvic transaminase) were estimated on the first, third, seventh, and twenty-first postoperative days, these results being compared with two groups of controls; the first, 19 patients who had lung resection, and the second, 20 patients who underwent closed mitral valvotomy. The mean levels remained normal in the two control groups, but were markedly elevated on the first and third days after operation in the open heart patients, in whom they had returned to normal by the twenty-first day. No correlation was found between the transaminase levels and the duration of either the perfusion or the coronary occlusion. Four deaths occurred in the 25 patients, in only one of which could death be attributed to the technique. The survivors have shown no evidence of impaired myocardial function, and the technique appears effective and safe when limited to a maximum of 60 minutes of continuous aortic occlusion.

Management of congenital aortic stenosis

72 patients with congenital aortic stenosis whose ages ranged from 1 month to 15 years were under supervision for periods ranging from several months to more than 9 years. The obstruction was subvalvar in 3. Additional malformations were aortic regurgitation, persistent ductus arteriosus, coarctation of the aorta, ventricular septal defect, partial anomalous pulmonary venous drainage, and mitral stenosis. Bacterial endocarditis complicated 3. Of 5 deaths unrelated to operation, 3 were sudden. Surgical treatment was carried out in 12 patients (commissurotomy, valve replacement with or without previous commissurotomy, subvalvar resection) with 2 deaths. 52 patients remained symptom-free. Detailed investigation to assess the patient for surgical treatment is indicated if symptoms are present or electrocardiographic evidence of severe left ventricular hypertrophy appears. Commissurotomy is, where possible, deferred until an age at which valve replacement can be undertaken if the stenosis cannot be adequately relieved without causing substantial regurgitation.

Mitral valve replacement: An analysis of 78 patients

A series of 78 patients with advanced mitral incompetence treated by mitral valve replacement with a Starr-Edwards prosthesis is reported. The overall early mortality was 24 (30.7 per cent) and a further 3 died later. The causes of these early and late deaths are fully analysed. Most occurred in the early part of the series, and there has been a dramatic decline in both mortality and morbidity in the later cases since adoption of continuous clamping of the ascending aorta during the period necessary for excising the valve and suturing the prosthesis in position. The average duration of aortic clamping has been 20 minutes. During the last year (1967) there have been only 5 deaths in 32 patients, representing a mortality of 15.6 per cent. It is emphasised that only patients who have severe incapacity due to mitral incompetence require operation, and neither age nor the degree of pulmonary vascular resistance is a bar to surgery. Advanced renal disease, generalised pulmonary emphysema, and recent myocardial infarction are the only three absolute contraindications.

The 54 survivors from operation have been closely supervised for periods varying from several months to as long as 4 years, and as mentioned above 3 have died during this time. The remaining 51 have shown a striking improvement in exercise tolerance, with reduction in heart size.

The various surgical procedures available for dealing with mitral incompetence are discussed. Plication of the valve would appear in our experience to be limited to a small number with non-calcific, mildly sclerotic, and only slightly distorted valves. Pig aortic heterografts or pulmonary autografts may offer scope in the future, but we contend that the Starr-Edwards ball-valve prosthesis, although admittedly not as yet ideal, is the best available at present. With the introduction of the latest modification of this valve (now marketed in Britain), thrombo-embolic phenomena should be reduced to a minimum.

Rheumatic mitral stenosis in association with parital anomalous pulmonary venous return

An unusual case is presented, in which mitral stenosis was accompanied by a persistent left superior vena cava communicating through a venous channel with the left pulmonary veins. The pulmonary veins were normally connected to the left atrium, but, due to elevation of the left atrial pressure from the mitral valve lesion, pulmonary venous blood was directed up the left superior vena cava to reach the right atrium. Although from an anatomical viewpoint this did not constitute true anomalous pulmonary venous drainage, the condition behaved as such haemodynamically. It was only at operation that the diagnosis was firmly established, but after mitral valvotomy the abnormal venous channel was obliterated by simple ligation without incident.

Cardiac arrhythmias following successful surgical closure of atrial septal defect

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Communication between the left ventricle and right atrium

A further 15 patients with left ventricular/right atrial communication are reported, 14 of whom were treated surgically. The clinical triad of a ventricular septal defect murmur, cardiac enlargement, and an arteriovenous shunt at atrial level is characteristic of the malformation. Of the 14 patients accorded surgical treatment, one died soon after operation. The remainder are well, with both the electrocardiographic signs of left ventricular hypertrophy and the radiographic evidence of cardiomegaly having undergone regression.

Congenital aorto-pulmonary fistula combined with persistent ductus arteriosus

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Empyema due to Klebsiella pneumoniae

Three cases of post-pneumonic empyema due to infection with Klebsiella pneumoniae are reported. All were men considerably debilitated by complicating factors. The presence of persistent fistulae and of lung necrosis makes eradication of this infection very difficult and tedious, and in the management of these cases the objective is to secure adequate removal of necrotic tissue, effective drainage, and finally a satisfactory deroofing procedure to obliterate the empyema cavity.