Local drug delivery at angioplasty treatment sites may improve acute and long-term results after angioplasty. A new dual-purpose balloon angioplasty catheter containing intramural channels and exterior pores ('channeled balloon') was designed to allow local drug delivery at low pressure without jet streams during simultaneous balloon angioplasty.Methods
Acute feasibility studies were performed in normal ex-vivo and in-vivo arteries (three canine arteries and three rabbits with normal iliac arteries), in which 2ml of marker agents were locally infused at 2atm during simultaneous angioplasty at 6 atm with the channeled balloon. Histology, radioactive counting, and autoradiography were performed to determine the intramural localization of the delivered markers. The in-vitro efficiency of acute local drug delivery was estimated in seven normal canine arteries by infusing 3H-heparin and radioactive counting.Results
Histology revealed the presence of markers in the inner third of the media in all ex-vivo samples, and markers in all in-vivo iliac arteries except for one, whereas control segments had no intramural staining. Autoradiography documented transmural radioactive granules. Radioactive counts were 40− to 263-fold higher in those locally treated with the radioactive marker agent. Efficiency of the acute local delivery was estimated by dividing the actual counts by the expected counts; it ranged from 24 to 48%.Conclusion
This study demonstrates that the channeled balloon is capable of delivering drugs locally at low pressure in adequate concentrations during simultaneous high-pressure balloon angioplasty in normal arteries.