An implantable pump Lenus pro® in the treatment of pulmonary arterial hypertension with intravenous treprostinil

Abstract

BackgroundSubcutaneous treprostinil is a prostacyclin analogue used to treat pulmonary arterial hypertension (PAH). Due to local pain it can cause a deterioration of heart related quality of life (HRQoL) or even abandonment of treatment. The aim of this paper was to assess the feasibility of treatment with intravenous treprostinil administered by means of the Lenus Pro® implantable pump.MethodsThis was a retrospective, multi-center study involving 12 patients (8 females) with PAH treated with a subcutaneous infusion of treprostinil with intolerable pain at the infusion site. Clinical evaluation, including HRQoL assessment with SF-36 questionnaire was performed, before pump implantation and 2–9 months after. The median time of follow-up time was 14 months (4–29 months).ResultsAfter implantation of the Lenus Pro® pump, no statistically significant changes were observed in the 6-min walking distance and NT-proBNP. After implantation 50% of patients were in II WHO functional class (33% before, p = 0,59). There was a significant improvement in HRQoL within the Physical Component Score (28 ± 7 vs 38 ± 8 pts., p < 0,001) and in specific domains of SF-36 form: physical role (31 ± 7 pts. vs. 41 ± 12 pts., p = 0,03), bodily pain (31 ± 12 vs. 50 ± 14 pts., p = 0,02), and vitality (37 ± 8 pts. vs. 50 ± 14 pts., p = 0,03). During the periprocedural period, one patient developed a recurrent haematoma at the implantation site. During follow-up in one patient, the drug delivering cannula slipped out of the subclavian vein, what required repositioning repeated twice, and in another patient an unexpected increase in the drug administration rate was observed.ConclusionsIn patients with PAH who do not tolerate subcutaneous infusion of treprostinil, the use of the Lenus Pro® implantable pump results in significant subjective improvement of vitality and physical aspect of the HRQoL with acceptable safety profile.

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

“…Reports of flow rate variance with the LENUS Pro Õ pump have been published previously. 3,5,8 The constant flow rate is regulated by a glass capillary, and it was speculated that chemical substances within the intravenous treprostinil sodium formulation slowly cause alterations within the glass capillary over a long period of time; 3 this is consistent with the results of the current study in which relevant flow rate variances only occurred in the third year after pump implantation. In the recently published long-term safety study of the LENUS Pro Õ pump, variances of the non-adjustable flow rate were classified as pump defects.…”

Antiplatelet effects of prostacyclin analogues: Which one to choose in case of thrombosis or bleeding?

“…However, data from clinical studies do not always comply with experimental insights. For example, it seems that epoprostenol and treprostinil may increase bleeding risk, especially if treprostinil is administered subcutaneously or intravenously [33][34][35]39]. In addition, a randomized controlled trial on 105 patients treated with treprostinil administered subcutaneously showed that the frequency of bleeding complications was not dose-related [38].…”

Elicitation of health state utilities associated with the mode of administration of drugs acting on the prostacyclin pathway in pulmonary arterial hypertension

“…These could potentially reduce some of the risks or impacts related with the devices described in this study. 56 , 57 However, implantable pumps require a general anesthetic to implant and are not suitable for all patients. Therefore, vignettes specifically to describe administration with an implantable pump were not developed for this study.…”