FEASIBILITY AND DRUG-DELIVERY EFFICIENCY OF A NEW BALLOON ANGIOPLASTYCATHETER CAPABLE OF PERFORMING SIMULTANEOUS LOCAL-DRUG DELIVERY

Background: Local drug delivery at angioplasty treatment sites may imp rove acute and long-term results after angioplasty. A new dual-purpose balloon angioplasty catheter containing intramural channels and exter ior pores ('channeled balloon') was designed to allow local drug deliv ery at low pressure without jet streams during simultaneous balloon an gioplasty. 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 2 ml of marker agents were loca lly infused at 2 atm during simultaneous angioplasty at 6 atm with the channeled balloon. Histology, radioactive counting, and autoradiograp hy were performed to determine the intramural localization of the deli vered markers. The in-vitro efficiency of acute local drug delivery wa s estimated in seven normal canine arteries by infusing H-3-heparin an d radioactive counting. Results: Histology revealed the presence of ma rkers in the inner third of the media in all ex-vivo samples, and mark ers in all in-vivo iliac arteries except for one, whereas control segm ents 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 coun ts 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 simul taneous high-pressure balloon angioplasty in normal arteries.