Inhaled iloprost is a potent acute pulmonary vasodilator in HIV-related severe pulmonary hypertension

As antiretroviral therapy has improved life expectancy in human immunodeficiency virus (HIV) infection, the life-limiting complication of HIV-related pulmonary hypertension has come into focus. Inhalation of the stable prostacyclin analogue iloprost is an effective treatment for various forms of precapillary pulmonary hypertension. The main objective of the present study was to evaluate the safety and efficacy of inhaled iloprost in HIV-related pulmonary hypertension. In eight patients with severe pulmonary hypertension related to HIV infection, right heart and femoral artery catheterisation were performed. The acute effect of oxygen, inhaled nitric oxide and aerosolised iloprost was investigated. Four patients underwent long-term treatment with inhaled iloprost. The rank order of pulmonary vasodilatory potency was iloprost>NO>O2, with a maximum reduction (mean +/- SEM) in pulmonary vascular resistance of 30.6 +/- 3.1% (p < 0.001), 5.9 +/- 3.9% and -0.6 +/- 3.9%, respectively. Concomitantly, inhaled iloprost significantly increased the cardiac index and central venous oxygen saturation. Chronic treatment with inhaled iloprost tended to improve the 6 min walking distance and decreased pulmonary vascular resistance in all patients (although not significantly). No serious adverse events and no major interactions with the ongoing antiretroviral therapy were noted. In conclusion, inhaled iloprost is a potent pulmonary vasodilator in human immune deficiency virus-related pulmonary hypertension. Future studies are warranted to confirm the encouraging long-term beneficial results observed in the present limited number of patients.