Effect of prolonged inhibition of angiotensin converting enzyme by captopril on some hemodynamic parameters of pulmonary circulation in patients with secondary pulmonary hypertension.

The effect of prolonged treatment with captopril on some parameters of pulmonary circulation was studied in a group of 17 patients with secondary pulmonary hypertension due to mitral stenosis. Each patient received 25 mg of captopril four times daily for mean time of means = 12.5 +/- 2.1 days. A drop in pulmonary artery mean pressure of at least 20% was observed in 5 patients (29.4%). In 4 patients (23.5%) captopril had adverse effect on the hemodynamics of the pulmonary circulation, and in 8 patients no effect of captopril on the pulmonary hypertension was noticed. Our model of the experiment did not allow us to select before the treatment the group of patients in whom positive effects of captopril could be expected.