Implantable infusion pumps might improve the convenience and safety of intravenous treprostinil for pulmonary arterial hypertension. The LENUS Pro® pump (approved in Europe) has a fixed flow rate. Based on 126 pumps and 2853 refills, we retrospectively analyzed the actual flow rate from 09/2010 to 09/2018. A relevant flow rate variance is evident after three years; therefore, flow rate monitoring and dose adjustment are mandatory.

BACKGROUND:We examined safety and long-term outcomes of intravenous treprostinil administered via the implantable LENUS Pro pump in patients with severe pulmonary hypertension (PH). METHODS:Patients with PH undergoing pump implantation between December 2009 and October 2016 in German referral centers were retrospectively analyzed (end of follow-up: May 2017). The primary objective was to determine long-term safety of the implantable pump. Secondary end points were 3-year survival and prognostic relevance of pre-implantation hemodynamics. RESULTS:We monitored 129 patients (120 with pulmonary arterial hypertension, 1 with PH due to lung diseases, and 8 with inoperable chronic thromboembolic PH) for 260 patient-years (median follow-up, 19 months; interquartile range, 11-34 months). There were 82 complications/peri-procedural events in 60 patients; of these, 57 were serious adverse events (0.60 per 1,000 treatment-days), including 2 periprocedural deaths due to right heart failure. The incidence of complications related to the pump, catheter, infection, and pump pocket per 1,000 treatment-days was 0.074, 0.264, 0.032 (3 local infections; no bloodstream infections), and 0.380, respectively. Three-year overall and transplant-free survival were 66.5% and 55.7%, respectively (39 patients died; 16 underwent lung transplantation). Baseline cardiac index independently predicted transplant-free survival (multivariate hazard ratio, 1.90; 95% confidence interval, 1.11-3.28; p = 0.019; n = 95). CONCLUSIONS:Our data suggest that intravenous treprostinil via the LENUS Pro pump in advanced PH is associated with a very low risk of bloodstream infections, but other serious adverse events may occur. Therefore, this therapy needs standardization and should be offered in specialized PH centers only. Further technical advances of the pump system and prospective studies are needed.

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.