Local delivery of nadroparin via hydrogel-coated angioplasty balloon: Effect on platelet deposition and smooth muscle cell proliferation - An experimental study

PURPOSE: To assess the feasibility of intravascular delivery of nadroparin, a low-molecular-weight heparin, via hydrogel-coated angioplasty balloons, and the effects of nadroparin delivered in this manner on platelet depositi on and smooth muscle cell (SMC) proliferation, MATERIALS AND METHODS: Tritiated nadroparin was used to determine the nadro parin-carrying capacity of the hydrogel-coating, kinetics of release from t he balloons, and, in four pigs, delivery of the nadroparin to the iliac art erial wall. Platelet deposition in nadroparin-treated iliac arteries versus contralateral iliac arteries dilated with saline-loaded, hydrogel-coated b alloons was quantified in seven pigs using (111)Indium-labeled platelets. S mooth muscle cell proliferation in nadroparin and saline-treated iliac arte ries in 10 pigs was evaluated 7 days after angioplasty with use of prolifer ating cell nuclear antigen. RESULTS: Approximately 98 international units of nadroparin were delivered by the hydrogel-coated balloon, the majority to the angioplasty site and di stal vessel. There was a trend toward decreased platelet deposition in nadr oparin-treated arteries, but statistical significance was not achieved (P = .1563). Medial SMC proliferation was decreased in the nadroparin-treated a rteries in nine of 10 pigs (P = .0137). CONCLUSIONS: Hydrogel-coated balloons may be used to deliver nadroparin to the arterial wall, with measurable levels of the drug delivered to the site of angioplasty, and with resultant decrease in SMC proliferation.