| abstract |
There is disclosed a radially expandable stent for intravascular implantation comprising a distensible frame and an impermeable deformable membrane interconnecting portions of the frame to form an impermeable exterior wall. The membrane is formed of a synthetic non-latex, non-vinyl polymer, and the frame comprises a fine wire of annealed platinum. The comprises a plurality of helically aligned circumferential sections including two end sections and a plurality of intermediate sections that define a cylinder having a longitudinal axis, the cylinder being formed of a continuous wire with the circumferential sections being spaced along the axis in abutting contact. Each of the circumferential sections have expandable segments that impart radial expandability to the sections. The expandable segments are tear-drop shaped elements that are alternately inverted about the circumferential sections, each element containing a base and a pair of legs that come together at a common apex when the stent is in an unexpanded condition. One of the end sections has a pigtail that is passed back along the circumferential sections and is joined to the other end section to prevent axial expansion of the expanded during radial expansion. |