[Study of 20 cases of apparently primary pulmonary arterial hypertension].

The authors have studied the clinical, electrocardiographic, radiological, phonomechanographic and haemodynamic features of 20 cases of apparently primary pulmonary hypertension of fairly severe degree. An attempt has been made to correlate on the one hand the haemodynamic values, and on the other the clinical findings, ECG signs of right-sided preponderance, the size of the artery to the right lower lobe on X ray, and the phonomechanographic results. Particular importance is given to a discussion on the aetiology. It is recalled that syphilis can be excluded, that it is possible the operate on thromboses, and that bilharzia and the haemoglobinopathies may play a part which is yet to be defined.