Pulmonary arterial hypertension (PAH) patients with moderate, stable disease can benefit from an implantable drug delivery system, based on data from a review of 60 adults with successful implantations. The findings were published in the December issue of CHEST.
“A fully implanted system offers patients the hope of returning to more normal activities such as bathing, swimming, and reduced risk of infections from externalized central venous catheter contamination or reduced subcutaneous pain from subcutaneous infusion,” wrote Aaron B. Waxman, MD, PhD, of Brigham and Women’s Hospital, Boston, and his colleagues (Chest. 2017 June 3. doi: 10.1016/j.chest.2017.04.188).
In the DelIVery Trial, clinicians at 10 locations in the United States placed a fully implantable delivery system in adults aged 18 years and older with stable PAH who were previously receiving treprostinil via an external pump at an average dose of 71 ng/kg per min.
All 60 patients were successfully implanted with a system consisting of a drug infusion pump placed in an abdominal pocket and an intravascular catheter linking the implanted pump to the superior vena cava.
“The location of the pump pocket was determined in partnership with the patient and was based on consideration of clothing styles, belt line and subcutaneous fat depth,” the researchers noted.
Procedure-related complications deemed clinically significant included one atrial fibrillation, two incidences of pneumothorax, two infections unrelated to catheter placement, and three catheter dislocations (two in the same patient). The most common patient complaints were expected implant site pain in 83% and bruising in 17%.
The findings were limited by the small number of patients, but the researchers identified several factors that contributed to the success of the procedure, including selecting patients who have shown response to treprostinil and are motivated to comply with pump refill visits, performing the procedure at centers with a high volume of PAH patients, keeping the procedure consistent for each patient, and using the same implant team in each case. “The implant procedure was successfully performed with a low complication rate by clinicians with a diverse range of specialty training,” the researchers added.
Patients reported satisfaction with the implant system at 6 weeks and 6 months, and said they spent an average of 75% less time managing their delivery system, according to previously published data on the patients’ perspective (CHEST 2016;150[1]:27-34).
Medtronic sponsored the study. The lead author, Dr. Waxman, had no financial conflicts to disclose; several coauthors reported relationships with companies including Medtronic, Actelion, Bayer, Gilead, Merck, and United Therapeutics.