BACKGROUND In patients with severe pulmonary arterial hypertension, subcutaneous or catheter-based intravenous application of prostanoids carries a risk of local side effects or systemic infections, which limits their use and acceptance. Recently, a fully implantable pump for continuous application of intravenous treprostinil was approved in Germany. However, surgery is a major risk for patients with severe pulmonary arterial hypertension. The purpose of this study was to investigate the safety of a fully implantable pump inserted under local or general anesthesia in patients with severe pulmonary hypertension. METHODS All patients with pulmonary hypertension undergoing pump implantation for the continuous application of intravenous treprostinil were included from two German centers. Surgery was performed under local or general anesthesia according to the protocol of the recruiting center. Intra-operative safety and in-hospital complications were analyzed for the two different implantation regimens. RESULTS In total, 51 patients were included. No major intra-operative complications were recorded. During the observation period, two patients died of progressive right heart failure, and two patients required treatment in the intensive care unit for acute right heart decompensation and respiratory failure. In total, major complications occurred in 8 out of 51 patients. CONCLUSIONS Our observational study provides preliminary evidence supporting the procedural safety of a fully implantable pump inserted under local or general anesthesia for patients with severe pulmonary hypertension. The observation of major complications in a subset of patients requires extensive pre- and post-operative assessments. Future trials are required to provide further evidence for the long-term safety and efficacy of the pump using this approach.