Primary pulmonary hypertension is a progressive, therapy-resistant illness associated with a median survival of 2.8 years; the mortality rate correlates with measures of right ventricular function [1]. A promising new therapeutic strategy includes long-term intravenous [2] or aerosolized [3] administration of prostacyclin.

Recent reports suggest an increased incidence of pulmonary hypertension, probably unrelated to the degree of immunodeficiency, in HIV-infected persons [4]. We describe two HIV-infected patients with pulmonary hypertension who were treated for 7 months with aerosolized prostacyclin. Both 33-year-old, formerly drug-addicted men were given a diagnosis of pulmonary hypertension after the American College of Chest Physicians published its consensus algorithm [5]. The patients' CD4⁺ counts ranged from 200 to 400 cells/mm³, and symptoms were dyspnea in New York Heart Association (NYHA) class IV. Catheterization of the right side of the heart confirmed severe pulmonary hypertension, with mean pulmonary artery pressures of 73 and 53 mm Hg, respectively. Epoprostenol (Flolan, Glaxo-Wellcome, United Kingdom) was jet-nebulized with room air and subsequently inhaled (Pari IS-2, Starnberg, Germany; 40% of droplet size <3 microm), starting with a dosage of 2 ng/kg of body weight per minute and increasing by 10-minute increments to a dosage as high as 40 ng/kg per minute.

Mean pulmonary artery pressure decreased from 73 to 62 mm Hg and from 53 to 47 mm Hg, respectively; pulmonary vascular resistance decreased from 1093 to 945 dynes/sec · cm^–5 and from 860 to 837 dynes/sec · cm^–5. Cardiac index and PaO₂ values did not change. One patient subsequently initiated long-term treatment with inhalations of aerosolized epoprostenol, 40 µg/d six times a day; the other patient received inhalations of iloprost (Ilomedian, Schering AG, Berlin, Germany), the more stable analogue of prostacyclin, 8 µg/d six times daily. Echocardiographically obtained values of estimated pulmonary artery pressure confirmed a sustained response of the pulmonary vasculature, and repeated treadmill tests showed increasing walking distances with a reduction of dyspnea from NYHA class IV to class II (Figure 1). Treatment caused no adverse events. We could not assess any tolerance effects with long-term use of both drugs; however, when treatment was interrupted for 10 days in one patient, pulmonary artery pressure rapidly increased to pretreatment values.

View larger version (19K): [in this window] [in a new window]   Figure 1. Echocardiographically estimated systolic pulmonary artery pressure and walking distance as a function of time during long-term therapy with inhaled prostacyclin in two HIV-infected patients with pulmonary hypertension. Squares = pulmonary artery pressure in patient 1; circles = pulmonary artery pressure in patient 2; triangles = walking distance in patinet 1; diamonds = walking distance in patient 2.