Abstract
Eighteen patients with mitral stenosis and twelve patients with left-to-right shunts heart disease and six normal subjects were catheterized and plasma dopamine-β-hydroxylase (DBH) activities in various parts of cardiovascular system were measured in order to assess the role of sympathetic activity in pulmonary hypertension. Arteriovenous differences of DBH activities were positive in normal subjects and patients with normal pulmonary artery pressure. A negative difference was found in patients with pulmonary hypertension. DBH activity in patients with pulmonary hypertension was significantly elevated compared with that of normal subjects. There was a weak correlation between mean pulmonary artery pressure and DBH activity in pulmonary artery. There were significant differences between normal, mitral stenosis with pulmonary hypertension and left-to-right shunts heart diseases about the pattern of distribution of DBH activity among these groups. A significant difference of the distribution between mitral stenosis with normal pulmonary artery pressure and that with pulmonary hypertension was also found. These findings suggested that a prolonged, increased level of sympathetic nervous system activity among patients with mitral stenosis and left-to-right shunt heart disease developed pulmonary hypertension. Thus, a significant contribution of sympathetic nervous activity to the establishment of pulmonary hypertension was suggested.
