Porous balloon catheters for local delivery: assessment of vascular damage in a rabbit iliac angioplasty model.

OBJECTIVES

This experimental study assessed long-term vascular damage induced by the use of porous balloon catheters designed for local delivery.

BACKGROUND

Local drug delivery using porous balloon catheters has emerged as a possible means by which compounds designed to prevent restenosis might be delivered locally at concentrations higher than achievable by systemic administration. There are, nonetheless, some concerns about the possibility of greater arterial trauma induced by the high pressure fluid jets from the delivery catheter itself, a complication that could provide additional stimulus for intimal hyperplasia. Because these concerns are based mainly on in vitro studies and on studies performed after acute experiments, further work is required to assess the long-term effects of this device on the arterial wall.

METHODS

Local delivery of a saline solution was performed in 32 rabbits in one iliac artery, using an inflation pressure of 6 atm and a balloon/artery ratio of 1.3 to 1.5, followed by angioplasty in both iliac arteries. Vascular injury was assessed using tritiated thymidine incorporation at 4 days (12 rabbits) and planimetry at 30 days after the procedure (20 rabbits).

RESULTS

Tritiated thymidine incorporation did not reveal any significant difference between the angioplasty group and the group with local delivery and angioplasty (117,921 +/- 18,853 vs. 140,652 +/- 23,125 cpm/mg protein, p = NS). Planimetry at 30 days was also similar in the two groups (neointimal area 0.11 +/- 0.02 vs. 0.13 +/- 0.02 mm2).

CONCLUSIONS

In this model the use of porous balloon catheters before angioplasty did not lead to greater intimal hyperplasia than angioplasty alone. Further experimental investigation is required to determine whether this strategy could be used to prevent postangioplasty restenosis in humans.