Self-expanding endovascular stent in experimental atherosclerosis. Work in progress.

To investigate the physiologic and histologic responses induced by the self-expanding endovascular prosthesis, rabbits subjected to a combination of high-cholesterol diet and intravascular trauma underwent stent implantation. The results were compared with those obtained with the placement of stents in the healthy aortas of rabbits. Stents in healthy aortic tissue led to stent intimalization, previously reported in canine studies. For stents placed in animals subjected to a high-cholesterol diet but no intimal trauma, it was found that the stent was not the source of atherogenesis. Stents placed in atheromatous plaque were found to radially compress plaque with time and to stimulate for formation of a fibrotic crust. The results suggest that the self-expanding stent protects against progressive encroachment of the vessel lumen by atherosclerotic tissue.