Acute effects on pulmonary haemodynamics of nifedipine in adult patients with cystic fibrosis.

Hypoxic pulmonary vasoconstriction is considered to be the primary cause of pulmonary hypertension and cor pulmonale in adult patients with cystic fibrosis (CF). The acute effect on pulmonary haemodynamics of a single sublingual dose of nifedipine 20 mg has been studied in 9 adult patients with CF. Nifedipine significantly attenuated the rise in mean pulmonary artery pressure and pulmonary vascular resistance induced by inhalation of a 13% oxygen gas mix. It also slightly reduced baseline pulmonary artery pressure and pulmonary vascular resistance and lowered pulmonary artery hypertension in the patients. Oxygen delivery was unchanged. Nifedipine is potentially useful for the treatment of hypoxic pulmonary hypertension in patients with CF.