A device and method for treating pathological narrowing of fluid-carrying conduits of the human body (such as blood vessels) in an area of a bifurcation is disclosed. In particular, a stent system carries a self expandable noncylindrical stent, which is particularly suited for treating a widened portion of a blood vessel immediately proximal to a bifurcation. A stent delivery system is also disclosed, for delivering the stent such that a larger expanded diameter end of the stent faces the bifurcation, and a smaller expanded diameter end of the stent faces proximally in the main vessel.