Flow rate variance of a fully implantable pump for the delivery of intravenous treprostinil in pulmonary arterial hypertension.

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.

Long-term safety and outcome of intravenous treprostinil via an implanted pump in pulmonary hypertension.

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.

Tetraspanin CD82 affects migration, attachment and invasion of rheumatoid arthritis synovial fibroblasts.

Tetraspanins function as membrane adaptors altering cell-cell fusion, antigen presentation, receptor-mediated signal transduction and cell motility via interaction with membrane proteins including other tetraspanins and adhesion molecules such as integrins. CD82 is expressed in several malignant cells and well described as tumour metastasis suppressor. Rheumatoid arthritis (RA) is based on persistent synovial inflammation and joint destruction driven to a large extent by transformed-appearing activated synovial fibroblasts (SF) with an increased migratory potential. OBJECTIVE: CD82 is upregulated in RA synovial fibroblasts (RASF) compared with osteoarthritis (OA) SF as well as within RA compared with OA synovial lining layer (LL) and the role of CD82 in RASF was evaluated. METHODS: CD82 and integrin immunofluorescence was performed. Lentiviral CD82 overexpression and siRNA-mediated knockdown was confirmed (realtime-PCR, Western blot, immunocytochemistry). RASF migration (Boyden chamber, scrape assay), attachment towards plastic/Matrigel, RASF-binding to endothelial cells (EC) and CD82 expression during long-term invasion in the SCID-mouse-model were evaluated. RESULTS: CD82 was induced by proinflammatory stimuli in SF. In RA-synovium, CD82 was expressed in RASF close to blood vessels, LL, sites of cartilage invasion and colocalised with distinct integrins involved in tumour metastasis suppression but also in RA-synovium by RASF. CD82 overexpression led to reduced RASF migration, cell-matrix and RASF-EC adhesion. Reduced CD82 expression (observed in the sublining) increased RASF migration and matrix adhesion whereas RASF-EC-interaction was reduced. In SCID mice, the presence of CD82 on cartilage-invading RASF was confirmed. CONCLUSION: CD82 could contribute to RASF migration to sites of inflammation and tissue damage, where CD82 keeps aggressive RASF on site.

Proposed phase 2/ step 2 in-vitro test on basis of EN 14561 for standardised testing of the wound antiseptics PVP-iodine, chlorhexidine digluconate, polihexanide and octenidine dihydrochloride.

BACKGROUND: Currently, there is no agreed standard for exploring the antimicrobial activity of wound antiseptics in a phase 2/ step 2 test protocol. In the present study, a standardised in-vitro test is proposed, which allows to test potential antiseptics in a more realistically simulation of conditions found in wounds as in a suspension test. Furthermore, factors potentially influencing test results such as type of materials used as test carrier or various compositions of organic soil challenge were investigated in detail. METHODS: This proposed phase 2/ step 2 test method was modified on basis of the EN 14561 by drying the microbial test suspension on a metal carrier for 1 h, overlaying the test wound antiseptic, washing-off, neutralization, and dispersion at serial dilutions at the end of the required exposure time yielded reproducible, consistent test results. RESULTS: The difference between the rapid onset of the antiseptic effect of PVP-I and the delayed onset especially of polihexanide was apparent. Among surface-active antimicrobial compounds, octenidine was more effective than chlorhexidine digluconate and polihexanide, with some differences depending on the test organisms. However, octenidine and PVP-I were approximately equivalent in efficiency and microbial spectrum, while polihexanide required longer exposure times or higher concentrations for a comparable antimicrobial efficacy. CONCLUSION: Overall, this method allowed testing and comparing differ liquid and gel based antimicrobial compounds in a standardised setting.

Procedural safety of a fully implantable intravenous prostanoid pump for pulmonary hypertension.

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.