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Biomedical subjects

M J Raphael

Publications and source records attributed to M J Raphael.

At least 37 records · Page 2Linked to original sources
PubMed1981

Is preoperative localisation of insulinomas necessary?

During the past 20 years 33 patients suspected of harbouring an insulinoma have been investigated. 29 had laparotomy, and tumours were removed from 27.2 of the 29 and 1 other proved not to have an insulinoma, although preoperative imaging had suggested a tumour. Four different localisation procedures were used, and in some patients more than one technique was applied. Selective arteriography of branches of the coeliac axis showed the position of the insulinoma correctly in 9 out of 18 cases, but in all of these the tumour was felt at operation, so that the information provided was unnecessary. Arteriography gave false localisation in 4 patients and missed the tumour completely in 4 but was also negative in 1 patient not harbouring a tumour. Ultrasonic examination provided correct localisation in only 2 out of 11 instances and computer-assisted tomography in 1 out of 8. Insulin estimation in blood obtained at percutaneous transhepatic portal-venous sampling (THPVS) provided correct localisation in 2 out of 8 cases, but in only 1 of these was it needed to guide pancreatic resection. Localisation was spurious in 5 patients, and in 1 there was no evidence of a tumour at all. In 23 patients the surgeon felt and removed the insulinoma at the first operation. In 3 tumour was palpable at a second laparotomy some years later. In only 1 was no tumour felt at operation. The false-positive findings in the THPVS were caused by misinterpretation of data. For a peak of insulin concentration in the portal vein to be meaningful, it should exceed 200 mU/l and to be fully diagnostic it should be greater than 500 mU/l. Present imaging techniques are not precise enough to localise an insulinoma. An experienced surgeon has a very high probability of being able to palpate the tumour at operation, and preliminary localisation is therefore not needed in most cases.

Adenoma, Islet Cell↗
PubMed1980

The angiographic anatomy of the coronary arteries.

The angiographic anatomy of the coronary arteries is described and illustrated by three corrosion casts of normal human hearts, photographed in projections comparable to those used in coronary arteriograms. They are accompanied by matched normal coronary arteriograms. The study of casts of the heart and of the coronary arteries in particular facilitates understanding of the radiographic projections commonly employed in coronary arteriography.

Coronary Angiography↗
PubMed1980

Assessment of long-term plasma exchange for familial hypercholesterolaemia.

The effectiveness of repeated plasma exchange with 2 to 4 litres of plasma protein fraction as long-term treatment for familial hypercholesterolaemia has been evaluated in six severely affected patients receiving conventional cholesterol lowering treatment. Cell-separator mediated exchange at monthly intervals for one to two years reduced mean serum cholesterol levels from 18.5 mmol/l (715 mg/dl) to 12.4 mmol/l (480 mg/dl) in two female homozygotes but failed to influence xanthomata or prevent a two- to threefold increase in their left ventricular aortic systolic pressure gradients. More effective reduction of mean serum cholesterol levels from 15.7 mmol/l (608 mg/dl) to 8.6 mmol/l (333 mg/dl) in two male homozygotes by plasma exchange at fortnightly intervals for two to three years was accompanied by resolution of xanthomata and by stabilisation of aortocoronary lesions. In two male heterozygotes with angina, coronary angiographic appearances were unaltered or improved after one to two years of thrice-monthly plasma exchange, which reduced mean serum cholesterol levels from 6.4 mmol/l (248 mg/dl) to 4.7 mmol/l (182 mg/dl). We conclude that plasma exchange every one to two weeks, combined with oral nicotinic acid and/or cholestyramine, retards the rate of progression of atheroma in homozygotes and possibly induces regression in heterozygotes.

Adult↗
PubMed1979

Anomalous origin of the left anterior descending coronary artery from the pulmonary trunk.

An extremely rare congenital abnormality is reported in which the anterior descending branch of the left main coronary artery arises independently from the pulmonary trunk in a young patient who presented with unstable angina. Its clinical presentation, angiographic identification and surgical treatment are described. It appears to be a distinct entity with few of the features of the classical form of anomalous origin of the left main coronary artery.

Adult↗
PubMed1978

Unusual chest X-ray appearances in hypertrophic cardiomyopathy.

The plain chest X-ray of 12 patients with hypertrophic cardiomyopathy were found to be grossly abnormal and atypical of this disease. Four patients presented with enlarged globular shaped hearts suggesting dilatation of all cardiac chambers. In a further four this appearance was seen to develop over a period of years and four patients were found with marked left atrial enlargement. On reviewing the echocardiographic, angiographic and necropsy data it was noted that the cardiac enlargement was produced by dilation of the atria and the right ventricle but not the left ventricle.

Adult↗
PubMed1978

Left ventricular function in ischaemic heart disease. A review.

The clinical significance of the abnormalities seen at left ventriculography in ischaemic heart disease is discussed. Aneurysms may be recognized when left ventriculography is combined with coronary arteriography to show the characteristic obliteration of the supplying artery. Localized areas of abnormal contraction seen at rest are almost certainly indicative of infarcts. Similar areas provoked by exercise or atrial pacing represent the site of acute ischaemia. The ischaemic ventricle may be recognized by abnormal response to exercise, even in the absence of angina. The abnormal response may be reversed by successful revascularization surgery.

Angina Pectoris↗
PubMed1977

QRS voltage of the electrocardiogram and Frank vectorcardiogram in relation to ventricular volume.

Left ventricular volumes were estimated in 59 patients, who were investigated by single plane ventriculography and coronary arteriography. The relation of the left ventricular end-diastolic volumes to the QRS voltage of the 12-lead electrocardiograms and Frank vectorcardiograms was examined. It was found that the maximum spatial QRS voltage and the R wave voltage of leads V5 and V6 in patients without left ventricular hypertrophy were inversely correlated with end-diastolic volume. This inverse relation of QRS voltage and left ventricular volume may explain loss of QRS voltage with dilatation of the heart. In patients with left ventricular hypertropy QRS voltage is usually positively correlated with the degree of hypertrophy, but there is no significant correlation in the presence of cardiac dilatation. If the results of this study are extrapolated to patients with left ventricular hypertrophy and cardiac dilatation, then the inverse correlation of volume and QRS voltage may reduce the diagnostic sensitivity of unipolar chest lead and vectorcardiographic criteria of left ventricular hypertrophy.

Cardiac Volume↗
PubMed1977

Primary restrictive cardiomyopathy. Non-tropical endomyocardial fibrosis and hypereosinophilic heart disease.

Eleven patients with a restrictive cardiomyopathy are described. Seven of these had biventricular disease and in them the haemodynamic abnormality resembled that in constrictive pericarditis but the condition was distinguishable because of unequal involvement of the two ventricles, murmurs of atrioventricular valve regurgitation, or characteristic ventricular deformity on angiography. Two of these patients had eosinophilia with the clinical features of Löffer's endocarditis. In 4 patients the disease was apparently confined to the left ventricle; they were investigated on account of atypical chest pain, third heart sound, or abnormal electrocardiogram. Simultaneous measurements of left ventricular pressure and volume throughout diastole were made in 3 patients and showed rapid but abruptly curtailed left ventricular filling. Transvenous endomyocardial biopsy in 2 patients showed fibrous tissue with collagen and irregular elastic fibrils. Surgical biopsy in 3 patients excluded pericardial constriction but was diagnostically unhelpful because of failure to obtain endocardium. Necropsy in one patient showed that the heart had features indistinguishable from tropical endomyocardial fibrosis. It is suggested that the spectrum of ventricular abnormalities in these patients results from endomyocardial fibrosis of varying severity and probably of differing cause. This study has shown that "tropical" endomyocardial fibrosis may occur outside the tropics and suggests that eosinophilia may play a leading role or associated part in the genesis of some cases.

Adult↗
PubMed1976

Exercise tests before and after heart valve replacement.

A simple progressive exercise test was performed before and after operation on five subjects undergoing mitral valve replacement and on five subjects undergoing aortic valve replacement. The responses of heart rate and ventilation were related to work rate )kilopond metres/min). The patients were also assessed clinically by the New York Heart Association grading and radiologically before each exercise test. The clinical grading was shown to be a poor guide to observed exercise tolerance, as the improvement noted in symptoms was not matched by the objective measurement of working capacity. Only two patients had normal exercise tolerance after surgery, although six of the ten patients claimed that they had no exertional dyspnoea after operation. The changes in simple ventilatory function tests before and after operation were generally small. We suggest that measurements of exercise tolerance before and after operation should be an essential part of heart valve replacement surgery.

Adult↗
PubMed1976

Angiographic anatomy of the right heart.

Casts of human hearts were prepared and photographed to illustrate the anatomy of the right heart chambers and ventricular septum. The casts were used to illustrate the anatomy of certain common pathological abnormalities of the ventricular septum and the appearances compared to angiocardiograms.

Angiography↗
PubMed1976

Continuous imaging of regional myocardial blood flow in dogs using krypton-81m.

The unique physical properties of the freely diffusible gas krypton-81 m allowed continuous imaging of regional myocardial blood flow in dogs when infused into the aortic root. Regional changes in myocardial perfusion related to transient coronary artery occlusion were demonstrated both as high resolution gamma camera images and as a quantitative strip chart record.

Animals↗
PubMed1976

Left ventricular angiography on exercise. A new method of assessing left ventricular function in ischaemic heart disease.

Left ventricular function was studied in 17 patients with ischaemic heart disease and compared with 4 patients with normal left ventricular function. The patients in the homogeneous group of ischaemic heart disease were further subdivided into those 'without angina' (n=5) and those 'with angina' (n=12), depending upon the presence of angina during supine leg exercise at the time of definitive study. At rest there was no significant difference in the heart rate, cardiac output, stroke volume, and left ventricular end-diastolic pressure (LVEDP) in the three groups. During exercise the cardiac output and stroke volume were significantly depressed and LVEDP was significantly raised in the ischaemic heart disease group as a whole but within this group failed to show any significant difference in patients with and without angina. The left ventricular end-diastolic volume (LVEDV) and end-systolic volume (LVESV) measurements showed clear separation of these three groups only on exercise. On exercise, there was decrease in LVEDV and LVESV (P less than 0.05; P less than 0.02) in the group with normal left ventricular function, no change in the group with ischaemic heart disease without angina, and striking increase in LVEDV and LVESV in the group with ischaemic heart disease and angina (P less than 0.01 and P less than 0.02, respectively). This angiographic method of assessing left ventricular function shows clear separation of the three groups and also highlights the significance of angina. Ejection fraction (EF), a commonly measured parameter of left ventricular function, failed to reflect consistent changes on exercise as compared to values at rest which emphasizes the limitations of the measurement of ejection fraction at rest.

Adult↗
PubMed1975

The functional defect in amyloid heart disease. The "stiff heart" syndrome.

Left ventricular performance was studied in three patients with heart failure due to amyloid deposits. The diagnosis of amyloidosis was proved by cardiac biopsy in two patients and by rectal biopsy in the third. One patient had myelomatosis, but the other two had no other identifiable disease. The investigative technique allowed simultaneous measurements of pressure and volume in the left ventricle. The functional defect with slow cardiac filling at high pressure and greatly reduced left ventricular contraction differed from that of constrictive pericarditis and other heart muscle disease. These features of a "stiff heart" are probably unique to amyloidosis and should make possible positive recognition of the condition on the basis of echocardiographic, angiographic and hemodynamic findings.

Adult↗