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The comparative ventilatory responsiveness to CO2 was studied in 13 chronic bronchitics and 14 emphysematous patients, all exhibiting respiratory insufficiency and with FEV1 less

The innominate vein usually lies superior to the aorta: using a suprasternal approach and an injection of contrast in the left arm, it is the earliest and most cephalad structure to be opacified. The aortic arch, right pulmonary artery and left atrium lie respectively below it. This relationship of these four structures is constant in all arrangements of the great arteries, forming the basis of contrast echocardiographic identification of the great vessels in cases of transposition. A case is reported of an innominate vein, the first structure to be opacified, lying inferior to the aortic arch and above the right pulmonary artery. This anomaly seems to be very rare.

The comparative ventilatory responsiveness to CO2 was studied in 13 chronic bronchitics and 14 emphysematous patients, all exhibiting respiratory insufficiency and with FEV1 less than 1,500 ml. The gas inhaled was enriched with oxygen (F1O2 =0.6) and contained 6% CO2, and measurements were taken when the patients had reached a stable state. The ratio delta VE/deltaPaCO2, which represents the ventilatory responsiveness to CO2, was higher in the emphysematous patients (1.18+/-0.51 liters-min-1. Torr-1) than in the bronchitics (0.76+/-0.34, p less than 0.025), but the deviation on either side of the mean was large in each group. The ventilatory responsiveness to CO2 was proportional to the initial PaCO2, FEV1, total airways resistance, total pulmonary work and especially to inspiratory mechanical work done on the lung ( r=-0.73, p less than 0.001). The difference in ventilatory responsiveness to CO2 between the bronchitic and emphysematous patients may be explained by the difference in energy expended in breathing. It was not possible to exclude an effect due to a difference in sensitivity within the respiratory centers, since inspiratory mechanical work was not measured during CO2 inhalation. It was thought likely that mechanical factors play a triggering role, in that they cause a fall in ventilatory responsiveness to CO2 and hypercapnia, the latter causing the central hyposensitivity which maintains the retention of CO2.

Certain pulmonary stenoses differ markedly from the usual types of isolated valvular stenosis in their clinical features (maximal murmur situated lower down), their radiological signs (absence of a prominent median arc), the electrocardiograph (atypical electrical axis), the haemodynamic findings (usually a poor gradient), and especially the angiocardiography (valvular dysplasia, lack of a post-stenotic dilatation). They are encountered especially in the multiple malformations, as shown by this series of 23 cases comprising the syndrome of Noonan (9), of Gorlin or 'leopard' (7), of Watson or 'café-au-lait spots' (3), or those defying classification, but always having a disorder of facial structure and mental deficiency, sometimes with deafness (4). The frequent finding of a gradually progressive hypertrophic cardiomyopathy is a feature of these syndromes, and usually accounts for the abnormal ECG findings. It leads to a discussion of the pathogenesis, and of the place of these syndromes in a wider context, alongside the phacomatoses and the hereditary forms of neuromuscular degeneration.

We collected 98 cases of single atrial septal defect. Analytical study of the pulmonary vasculature and the shape of the heart allowed us to differentiate 71 cases of pulmonary hypervascularity with increased cardiothoracic index and an appearance of right ventricular dilatation. The left inferior segment was usually straight, but sometimes convex, with a great curvature including the middle left segment. Apart from these 71 typical cases, there were 18 cases of incomplete patterns, 7 cases of atypical patterns with a convex left inferior segment with a small curvature and two normal cases (normal shape of the heart and normal vasculature). - Echocardiography was performed in 35 cases. It was valuable in 34 cases and established the diagnosis each time the X-ray picture was uncertain. Increase of the ratio of the telediastolic diameter of the right to left ventricle is almost constant and the septal motion is paradoxical in 79% of all cases. - Post-operative change was characterized from the radiological point of view by rapid return to normal of the pulmonary vascularity, followed by decrease of the cardiothoracic index, while the modifications of the shape of the left middle and inferior segment regress slowly and incompletely. As for echocardiography there is constant decrease of the ratio of the telediastolic diameter of the right to left ventricle, while the septal motion returns to normal in 79% of all cases.

This study was undertaken in 39 patients with Fallot's tetralogy associated with one or more cardiovascular malformations. Some common anomalies, simple anatomical variations were excluded (right sided aortic arch, patent foramen ovale). Out of a total of 48 anomalies (6 children had 2, 3 or 4 associated malformations) there were 5 anomalous systemic venous drainages (including 4 supernumerary left superior vena cava), 8 secundum atrial septal defects (including one multiperforated defect), 2 muscular ventricular septal defects, 7 atrioventricular canals (5 in mongol children); 1 tricuspid hypoplasia, 1 absent left pulmonary artery, 1 mitral valve prolapse, 1 obstructive cardiomyopathy, 10 coronary anomalies (including 5 ectopic left anterior descending arteries arising from the right coronary artery), 8 patent ductus arteriosus (arising from the left subclavian in 4 cases of right aortic arch), 3 retro oesophageal subclavian arteries and one congenital subclavian steal syndrome. The incidence of associated malformations was 15 p. 100, but values of up to 30 p. 100 have been reported mainly in anatomical studies. The authors emphasise the diagnostic and therapeutic implications of these associated malformations. In most cases, especially Fallot's tetralogy with an endocardial cushion defect, 2D echocardiography proved to be an essential diagnostic tool. Catheter studies, however, remain necessary, especially for the detection of aortic and coronary anomalies: selective coronary angiography is sometimes required. Difficult surgical problems are mainly encountered when the associated anomaly has not been diagnosed preoperatively. Although the variations of systemic venous drainage are not of great importance, those of the aortic arch can influence the technique of palliative procedures. Muscular VSD must not be missed. Tricuspid hypoplasia may pose a complex surgical problem. Malformations of the left heart which are sometimes unrecognised, aggravate the situation considerably. The association of Fallot's tetralogy and atrioventricular canal can now be corrected under good conditions. Finally, variations in the coronary anatomy must be documented meticulously as they may contraindicate early complete repair.

Exercise tests can be carried out without risk in a child or young adult with asymptomatic congenital aortic stenosis. In such a case, the ECG at rest gives only a very poor indication of the severity of the stenosis, which often becomes worse with age. The only sinister findings is that of repolarisation defects, which are almost always absent at rest. Exercise, by causing an imbalance between myocardial oxygen consumption and oxygen transport, will cause "ischaemic" signs to appear on the ECG. At the same time, the absence of compensation of pressure is a very important sign of poor tolerance; the test can usefully be concluded by using a floating catheter to measure the pulmonary capillary pressure. The correlation between a positive test and the stenotic pressure gradient, measured on catheterisation at rest, is good; but "negative" tests may be found in certain cases with a tight stenosis, especially if maximal rate could not be reached. In cases of stenoses which were initially mild or moderate, this test is very useful as a follow-up procedure, as such stenoses may become worse with age and require surgical correction. It is also useful for assessing the results of surgery, and of rehabilitation.

Chest roentgenograms were carried out in 98 children with atrial septal defects and showed in 71 of them an increase of the pulmonary vascular markings, an increased heart index and right ventricular enlargement. In other children, abnormalities were either incomplete (18 cases) misleading (7 cases) or normal (2 cases). Echocardiogram was characteristic in 34 of 35 children showing an increased telediastolic ratio in virtually all cases and paradoxical septal motion in 79%. Postoperatively, chest roentgenographic findings include a return to normal of pulmonary markings and heart index while right ventricular enlargement regresses only partially. Echocardiograms show a decrease of the telediastolic ratio in all patients and a normal septal motion in 78%.

The value of pulmonary haemodynamic tests during physical exercise in chronic bronchitis was shown by the comparison of two groups of patients. In the first group (n=24) the PAP during exercise is lower than 30 torr. In the second it was over 30 torr. The PAP at rest was always lower than 20 torr. The load was 40 to 50 watts, i.e. an average O2 consumption of 500-600 ml.mm-1 m-2. The cardiac output doubled on average in exercise. Both groups varied markedly in their PAP at rest: 13.6 +/- 1.7 torr for the first group and 15.8 +/- 2.4 for the second (p less than 0.001). In fact differences in pressure during exercise (I=25.0 +/- 3.4 torr; II=39.6 +/- 7.4 torr, p less than 0.001) could be explained mainly by the differences of pulmonary vascular resistances (I=0.91 +/- 0.37; II=1.47 +/- 0.61, p less than 0.005): they tended to fall during effort in the first group and increased slightly in the second; and by the much higher increase in the pulmonary "capillary" pressure during exercise in the second group (I=12.5 +/- 4.4 torr; II=19.7 +/- 72 torr, p less than 0.001). The cardiac output during rest and exercise was equal in both groups. The haemo-dynamic "recovery delay" was much higher in the second group. The spirographic shortage was on the whole identical in both groups. PaO2 on average was higher in group I (p less than 0.05) where it improved during exercise (p less than 0.01). The PaO2 of the second group did improve during exercise. The haemodynamic differences were concomitant with the differences in gas exchanges during effort, of well known prognostic significance. As the "foretelling" of PAP in effort from the PAP at rest was quite poor, it appeared that haemodynamic test in effort has a real value in contributing efficiently to the differenciation of the degree in severeness. The threshold of 30 torr for PAP in exercise (and for the load mentioned above) seemed a good discriminating factor.