[Respiratory function in chronic obstructions of the large pulmonary arteries (study of 30 cases].

If diagnosis of chronic thromboses of pulmonary arteries is usually easy at the stage of confirmed chronic pulmonary heart, it is not so when dysponea is the only symptom of the disease. The authors report 30 cases of chronic thrombosis and remark that if respiratory alkalosis is very frequent, hipoxemia is often missing. On the other hand they observe 27 times out of 28 an increase of CO2 alveoloarterial difference; measuring the CO2 difference appears a safe and reliable test for detecting chronic thrombosis. It should take place in every systematic complete examination of unexplained dyspnoea.