The objective of this study was to present our clinical experience about scleroderma-related pulmonary hypertension in the patients treated with intermittent iloprost infusions. Eighty-one patients affected by systemic sclerosis (12 men, 69 women; 30 with diffuse pattern and 51 with limited pattern; mean age 55.1 years; mean duration of disease 105.3 months) have been treated with cyclic iloprost infusions for at least 15 months (range 15-126 months). During the last 4 months all patients underwent Doppler echocardiography in order to estimate the value of systolic pulmonary artery pressure. In 14 subjects (17.2%) systolic pulmonary artery pressure was = or > 35 mmHg. Four patients presented high systolic pulmonary artery pressure associated with pulmonary fibrosis (mean value 40.5 +/- 4.5 mmHg). Ten women (one with diffuse pattern of disease and nine with limited form) showed isolated high systolic pulmonary artery pressure; one of these patients underwent right heart catheterization which resulted normal. The remaining nine patients (mean age of 67.1 years; age at the onset of scleroderma 52.2 years) showed estimated systolic pulmonary artery pressure values between 35 and 50 mmHg. Among these patients affected by isolated pulmonary hypertension only one has been receiving bosentan in association with iloprost infusions. None of our scleroderma patients treated with cyclic iloprost infusions developed severe isolated pulmonary hypertension. In systemic sclerosis the multiple effects of iloprost on endothelium, platelets and cytokine network may counteract the vasospastic profile of lung microvasculature in pulmonary arterial hypertension and the consequent vascular wall remodelling, thus preventing the development of severe illness.