The role of pulmonary hypertension in the pathogenesis of bronchial asthma.

In patients with bronchial asthma, when blood pressure in the pulmonary artery is measured, very often hypertension is registered. This pulmonary hypertension is not secondary to hypoventilation, as in patients with chronic bronchitis or pulmonary emphysema, since patients with bronchial asthma are hyperventilating. The pulmonary hypertension in them must be therefore classified as primary. It is probable that its origin is in an allergic vasoconstriction of the pulmonary artery, occurring simultaneously with the well known bronchoconstriction.