Susanna Desole

Subcutaneous implantation of a new intravenous pump system for prostacyclin treatment in patients with pulmonary arterial hypertension

BACKGROUND Intravenous prostacyclin treatment is a well recognized option in patients suffering from pulmonary arterial hypertension (PAH), and remains the gold standard of treatment. However, intravenous prostacyclin treatment involves several limitations, because the available battery-driven pump systems carry the risk of line infections, catheter-related embolisms, thrombosis, and delivery system malfunctions. CASE REPORT We report for the first time, to the best of our knowledge, on the safe transition procedure from subcutaneous to intravenous treprostinil in a 74-year-old woman suffering from severe PAH (New York Heart Association functional class III), using a new implantable, gas-driven, intravenous pump device (LenusPro, Tricumed/OMT, Frittlingen, Germany). CONCLUSIONS This implantable pump system may overcome the well-known limitations and risks of commonly used delivery systems, and thus may provide a new option for continuous intravenous prostacyclin treatment in patients with PAH.

Successful treatment of portopulmonary hypertension with the selective endothelin receptor antagonist Sitaxentan

ZusammenfassungDie portopulmonale Hypertonie ist eine seltene Erkrankung, die durch das Vorhandensein eines erhöhten mittleren pulmonalarteriellen Druckes und dem gleichzeitigen Vorliegen einer portalen Hypertonie gekennzeichnet ist. Eine schwere portopulmonale Hypertonie gilt als Kontraindikation zur Durchführung einer Lebertransplantation. Zahlreiche Medikamente wie Prostazyklindrivate, Phosphodiesteraseinhibitoren wie auch duale Endothelinrezeptorantagonisten wurden in einzelnen Patienten versuchsweise eingesetzt. Die Wirkung eines selektiven Endothelinrezptorantagonisten wie Sitaxentan in diesem Kontext war bisher unbekannt. Wir berichten hier über die erfolgreiche Therapie mit oralem Sitaxentan über einen Zeitraum von drei Monaten, wobei sich sowohl die Leistungsfähigkeit wie auch die pulmonale Hämodynamik verbesserten. Zusätzlich kam es zu einer Verbesserung der portalen Hypertonie durch eine signifikanten Reduktion des Lebervenendruckes von 12 auf 8 mmHg. Der Einsatz selektiver Endothelinrezeptorantagonisten könnte somit eine neue Therapieoption für diese Patienten darstellen.SummaryPortopulmonary hypertension (POPH) is a rare complication of portal hypertension. Prostanoids have been shown to be effective in the treatment of POPH and have been used as a bridge to liver transplantation. More recently, case series revealed beneficial effects of both the dual endothelin receptor antagonist bosentan and the phosphodiesterase-5 inhibitor sildenafil. The efficacy of sitaxentan, a selective endothelin receptor A (ERA) antagonist in the reversal of POPH, is still unclear. We report a case of POPH that was successfully treated with oral sitaxentan. Haemodynamic and symptomatic improvements were maintained after a 12-week long-term treatment period. Additionally, hepatic vein pressure gradient significantly decreased from 12 mmHg to 8 mm after treatment with sitaxentan. This is the first reported case of a successful therapy with a selective ERA antagonist in a patient suffering from POPH. Oral sitaxentan therapy might be a promising new option for patients suffering from POPH.

EXPRESS: Intravenous treprostinil via an implantable pump in pediatric pulmonary arterial hypertension

Intravenous prostacyclin-based therapy improves survival in children with pulmonary arterial hypertension (PAH), but is typically administered via an external infusion pump, which places a considerable burden on the patient. Implanted pumps may overcome some of the limitations of external pumps. We describe the first long-term use of an implanted pump for intravenous treprostinil delivery in a pediatric patient with PAH. Our patient was experiencing marked dyspnea on exertion despite triple combination therapy with bosentan, sildenafil, and inhaled iloprost. Parenteral prostacyclin-based therapy was discussed and the patient rejected options involving external pumps; she finally chose intravenous treprostinil delivery via an implanted pump (LENUS Pro®; fixed flow rate; 20 ml reservoir). The patient underwent pump implantation in July 2012 (aged 14 years) under general anesthesia with no peri- or postoperative complications. She showed marked improvements in fatigue and dyspnea over the subsequent weeks, and her inhaled iloprost regimen was slowly decreased and stopped after six months. During follow-up, the pump showed an unexpected, progressive increase in flow rate that allowed a treprostinil dose of 170 ng/kg/min to be achieved, but at the cost of shortened intervals between refills. The pump was therefore replaced in August 2017 with a newer model with an adjustable flow rate (Siromedes®). A catheter dislocation was corrected under local anesthesia one week after the replacement surgery. The patient is currently receiving treprostinil 170 ng/kg/min with percutaneous refills every 12–13 days. Thus, implantable pumps might be a valuable alternative to external pumps for treprostinil infusion in pediatric PAH.