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A study of the left ventricular function based on the haemodynamic data combined with those provided by biplane cineangiography was performed in 35 cases with left ventricular volume overload (20 cases of mitral incompetence and 15 of aortic insufficiency). The importance of the haemodynamic changes and of the adaptation mechanisms set up were described. The more intense dilatation-hypertrophy of aortic incompetence than of mitral incompetence plays an essential part. The role of Starling's mechanism is underlined. Estimation of the contractile value of the myocardium, taken into account the mechanical overload and the conditions of late-diastolic lengthening of the fibre and of impedance to left ventricular ejection was determined. An obvious myocardial failure, demonstrated in approximately one third of the cases, by determination of some contractility indices estimated in the ejection phase, Vf sigma max in particular, the only one valid in the presence of valvular regurgitation. In the other cases, the moderate decrease of myocardial contractility was masked by compensatory mechanisms.

Modifications of the mechanical ventilatory function in 18 atopic asthmatic patients challenged with carbachol and mites are studied. The patients were chosen according to clinical and immunoallergiological criteria. All patients reacted to carbachol and only 11 of them to mites. In addition to classical changes in total pulmonary resistance and forced expiration parameters, we observed modifications in lung elastic properties, with an impairment of the P/V curves. Ventilatory data after mite extract aerosols were heterogeneous. Bronchial infection seemed to facilitate central bronchoconstriction to allergens with a large increase of Rtot from 0.425 to 2.226 kPa . liter-1 . s (3.19-16.70 mm Hg . liters-1 . s). The delay between mite challenge and bronchoconstriction was longer when peripheral obstruction occurred without a significant increase in Rtot.

Respiratory function in 27 subjects with at least one anomaly in ventilation mechanics suggestive of emphysema was compared with that of a control population by means of plethysmographic indices. Results showed that static compliance to CRF and compliance for a volume nil for the elastic properties of the lung on the one hand and alveolar compression for dynamic properties on the other hand, appear to be valid criteria for early diagnosis of emphysema.

The tracings of intra-uterine pressure changes that are made during normal labours in primiparous patients, whether the labours were normal or accelerated with oxytocin, were analysed using a semi-automatic time-lag with the help of system of 25 parameters. The classical data of pressures and of time have been made up with a study of the minima and maxima of pressure measurements and the drawing up of new indices to characterise the pressure wave form. A study of the correlations between the different groups of parameters made it possible to make a summary of the information from a smaller number of data which were identical for the two groups of delivery. In particular working out the surfaces dose not seem to give extra information over and above that derived from a simple calculation of the length and intensity of the contractions. A comparative statistical study confirms that in accelerated labour there is a rise in the basal tone, in the maximum pressure and in the frequency of contractions, and shows a minimal scatter of the values obtained which demonstrated that oxytocin has a regulating effect. Using parameters for the shape of contractions, quite independently of the units chosen to measure, has made it possible to design a typical form for the graph for each group of labours.

We studied 19 patients with abnormally high static lung compliances, which had been discovered during a routine pulmonary function test, changes in elastic lung properties and smoking habits after 4 years. We did not observe, as is usually reported in the literature, that cessation of smoking normalizes lung compliance. A falsely normalized lung compliance may be due to lung zones that cease to ventilate. High lung compliances in nonsmoking patients, without clinical and radiological pulmonary abnormalities, are not always pathological but must be supervised.