[Pulmonary hemodynamic monitoring in chronic respiratory insufficiency treated with almitrine bismesilate for 4 months in a double-blind study].

: Six subjects suffering from chronic airflow obstruction and respiratory failure were treated with oral almitrine bismesylate (3 mg/kg/day). Studies were made before and after 2 and 4 months treatment on: total ventilation, arterial blood gases, pulmonary artery pressure by a micro-catheter and cardiac out-put by rebreathing CO2. The results were compared with those of a placebo group of 3 subjects. While in the almitrine group a significant improvement in blood gases was observed, no change was seen in the two populations in either the haemodynamic or ventilatory variables. The medium term haemodynamic stability observed is contrasting with single dose effects of almitrine. This discrepancy could be due, at least in part, to a balance between the possible vasoconstrictor effect of almitrine bismesylate and vasodilator consequences of blood gases improvement.