Inhaled Iloprost for Severe Pulmonary Hypertension

The number of effective, long-term treatments for pulmonary hypertension is limited. In this double-blind, randomized trial, an aerosolized form of iloprost, a stable analogue of the pulmonary vasodilator prostacyclin, was assessed over a 12-week period. Iloprost had a beneficial effect on the combined end point of the distance walked in six minutes and an improvement in the New York Heart Association functional class. A continuous infusion of prostacyclin was the first therapy shown to reduce mortality in a controlled study of patients with severe pulmonary hypertension. 1 However, its use is associated with a number of serious drawbacks. The lack of pulmonary selectivity results in systemic side effects, tolerance leads to progressive increases in the dose, and there may be recurrent infections of the intravenous catheter. 2 As an alternative, inhaled nitric oxide possesses pulmonary selectivity, but it is less potent than prostacyclin in the pulmonary vasculature. 3 , 4 Moreover, an interruption in the inhalation of continuous nitric oxide may cause rebound pulmonary hypertension. 5 , 6 Designed . . .