A method to transluminally seed angioplasty sites with endothelial cells using a double balloon catheter

Acute arterial reocclusion and late restenosis following angioplasty may be partially caused by loss of the endothelial cell monolayer during balloon dilatation. Rapid restoration of the endothelial cell monolayer by endothelial cell transplantation has the potential to increase the antithrombotic nature of the angioplasty site and also to prevent myointimal hyperplasia which is the cause of late restenosis. We have investigated a method to transluminally deliver endothelial cells to angioplasty sites using a double balloon catheter with a central instillation port. Inflation of the balloons allows a segment of artery to be isolated from the circulation which may then be incubated with infused endothelial cells. The external iliac arteries of New Zealand white rabbits were dilated for 30s at 8 atm pressure using a 3mm balloon angioplasty catheter. Indium-111 labelled allogeneic rabbit endothelial cells were seeded onto the angioplasty site and retained in contact with the vascular surface for 30 min by continued inflation of the isolation balloons. After 30 min, the balloons were deflated and flow restored. Percentage cell retention was calculated by determining the gamma activity of the seeded angioplasty site, and referencing this to the contralateral sham seeded site. Results are expressed as a median with 95% confidence intervals and suggest that endothelial cells may be successfully delivered and retained on damaged vascular surfaces.