Placement of Covered Stents to Treat Hemodialysis Access Stenoses in the Cephalic Arch and Central Veins

Balloon angioplasty is used to open up a narrowing that forms in hemodialysis fistula. Two areas of particular problems are the terminal portion of the cephalic vein near the shoulder and the central veins in the chest. Although angioplasty is standard of care the treated narrowed segments of vein mostly renarrow within 3 months requiring retreatment to keep your dialysis access functional. Recently there has been introduction of a new technology called a covered stent graft. Initial studies suggest that placing this device across the area of narrowing leads to dialysis access staying open longer and needing less angioplasty treatments. This study is designed to compare angioplasty (standard of care) versus using a covered stent graft. The investigators will then look at the dialysis records and future fistulograms to see if there is decreased flow through the fistula at 3, 6 and 12 months after the initial procedure.