Background: Intravenous prostanoid therapy is one cornerstone of therapy for patients with pre-capillary pulmonary hypertension (PH). Long-term central venous catheters expose patients to infectious complications. Objectives: We report the incidence of catheter-related infection (CRI) and the spectrum of bacteria for ambulatory PH patients treated with iloprost via non-tunnelled central venous catheters from our Swiss referral centre in Zurich. Methods: Data from 15 PH patients treated with intravenous iloprost between May 2000 and June 2012 were reviewed. Results: We found 11 CRI in 4 cases by two different organisms. Pathogens found were Brevibacterium (55%), Micrococcus luteus (18%), coagulase-negative Staphylococcus (9%) and Staphylococcus aureus (9%), as well as unusual organisms such as Agrobacterium tumefaciens or Delftia tsuruhatensis. The overall CRI rate was 1.28 per 1,000 catheter days, or 0.47 per year. Conclusions: The incidence of CRI using long-term, non-tunnelled central venous catheters in PH patients treated with iloprost is low. Uncommon, rare pathogens causing CRI were found in a substantial number of patients.