Inhaled prostacyclin and iloprost in severe pulmonary hypertension secondary to lung fibrosis

Pulmonary hypertension is a life-threatening complication of lung fibrosis. Vasodilator therapy is difficult owing to systemic side effects and pulmon ary ventilation-perfusion mismatch. We compared the effects of intravenous prostacyclin and inhaled NO and aerosolized prostacyclin in randomized orde r and, in addition, tested for effects of oxygen and systemic calcium antag onists (CAAs) in eight patients with lung fibrosis and pulmonary hypertensi on. Aerosolized prostaglandin (PG)I-2 caused preferential pulmonary vasodil atation with a decrease in mean pulmonary arterial pressure from 44.1 +/- 4 .2 to 31.6 +/- 3.1 mm Hg, and pulmonary vascular resistance (R-L) from 810 +/- 226 to 386 +/- 69 dyn s cm(-5) (p < 0.05, respectively). Systemic arter ial pressure, arterial oxygen saturation, and pulmonary right-to-left shunt flow, measured by multiple inert gas analysis, were not significantly chan ged. Inhaled NO similarly resulted in selective pulmonary vasodilatation, w ith R-L decreasing from 726 +/- 217 to 458 +/- 81 dyn s cm(-5). In contrast , both intravenous PGI, and CAAs were not pulmonary selective, resulting in a significant drop in arterial pressure. In addition, PGI(2) infusion caus ed a marked increase in shunt flow. Long-term therapy with aerosolized ilop rost (long-acting PGI(2) analog) resulted in unequivocal clinical improveme nt from a state of immobilization and severe resting dyspnea in a patient w ith decompensated right heart failure. We concluded that, in pulmonary hype rtension secondary to lung fibrosis, aerosolization of PCI2 or iloprost cau ses marked pulmonary vasodilatation with maintenance of gas exchange and sy stemic arterial pressure. Long-term therapy with inhaled iloprost may be li fe saving in decompensated right heart failure from pulmonary hypertension secondary to lung fibrosis.