REACTION OF THE AORTIC-WALL TO 6 METALLIC STENT MATERIALS

Rationale and Objectives. We investigated the effects of various metallic stents on the aortic wall. Methods. The wires of Gianturco-type expandable metallic stents were plated with gold, silver, or copper or coated with Teflon or silicone. Stents were inserted into the aortas of 15 adult mongrel dogs. The time course of radiologic, macroscopic, and histologic changes in the aorta at the site of the stent was investigated at 1, 2, and 4 weeks after implantation. Results. The gold-plated stent appeared to produce fewer macroscopic and histopathologic changes in the aorta than the other types of stents. The neointima was thinnest with gold (83.9 +/- 40.3 mu m), followed by stainless steel (103.6 +/- 57.0 mu m), Teflon (115.0 +/- 30.2 mu m), silicone (209.6 +/- 25.9 mu m), silver (228.6 +/- 33.8 mu m), and copper (unmeasurable). With the copper-plated stent, the aorta suffered severe erosion of the vessel wall, marked thrombus formation, and aortic rupture. Conclusion. Gold is a useful intravascular material because it reacts only minimally with the vessel wall.