[Pulmonary hypertension in chronic respiratory tract obstruction: a combined study on haemodynamics and radionuclide ventriculography].

In 44 patients with chronic obstruction of the respiratory passages pulmonary artery pressures were measured by Swan-Ganz catheter and right-ventricular ejection fraction by radionuclide ventriculography (equilibrium method). Although there was no linear correlation between the haemodynamic parameters of afterload or preload of the right ventricle and global right-ventricular ejection fractions, sensitivity and specificity of radionuclide ventriculography were very good (87% and 83%, respectively) for the recognition of pulmonary hypertension during exercise tests. Global right-ventricular ejection fraction in patients without pulmonary arterial hypertension had a normal and significant rise from 52% to 58% on exercise. In the group with pulmonary hypertension mean right-ventricular ejection fraction fell during exercise from 47% to 46%. Radionuclide ventriculography in the assessment of right ventricular function, especially during exercise, provides useful pointers to the diagnosis of pulmonary hypertension due to chronic respiratory-tract obstruction.