Device and method for tacking plaque to blood vessel wall
A plaque tack device for treating atherosclerotic occlusive disease is formed as a thin, annular band of durable, flexible material having a plurality of barbs or anchoring points on its outer periphery for preventing it from being dislodged. The plaque tack may be used with a balloon angioplasty procedure or as a de novo treatment for blood vessel blockage to reopen the vessel lumen for desired blood flow. It has a width that is small relative to its diameter, to minimize the amount of foreign structure placed in the blood vessel. One or more tacks may be applied in positions along a plaque accumulation site as needed to stabilize the site and/or hold pieces of plaque out of the way of blood flow. The barbs of the tack may be pressed into the plaque and/or blood vessel walls by balloon expansion. Related methods of deployment and delivery devices are provided for insertion of the plaque tack in a compressed state into the blood vessel and expanding it back to its annular shape for holding plaque against the blood vessel walls.
1. A device for holding plaque against blood vessel walls in treating atherosclerotic occlusive disease, comprising:
a thin, annular band of durable, flexible material having a plurality of barbs on its outer annular periphery, said annular band being dimensioned and designed to be applied with an outward expansion force against the plaque to press and hold it against the blood vessel walls,
wherein each of said barbs is formed with a head having a sharp point integrally formed on a support body, and is made of a sufficiently rigid material so that, when the outward expansion force is applied, they pierce the plaque and maintain a locking relationship with the blood vessel walls;
wherein said annular band is formed as a flexible ring of pliable material with an array of outer barbs on an outer side of the ring, and an array of inner radial fingers, wherein the array of inner radial fingers are used to displace the outer barbs to lie horizontally flat in one axial direction when the fingers are pushed in the opposite axial direction.
2. A device according to claim 1 , wherein the annular band has a width in the axial direction of the blood vessel walls that is less than its diameter in order to minimize the emplacement of foreign structure in the blood vessel.
3. A device according to claim 1 , wherein the annular band is designed to be compressed, folded, or plied to take up a smaller-diameter volume for insertion into the blood vessel, wherein it can be released to expand, unfold or unply to its full diametral size within the blood vessel walls.
4. A device according to claim 1 , formed as a folding ring tack having V-shaped segments alternating with inverted-V-shaped points, said V-shaped segments enabling said ring tack to be folded to a smaller-diameter volume for insertion into a blood vessel.
5. A device according to claim 1 , wherein said barbs are formed with conduits for enabling plaque treatment material to be conducted to the surface of the barbs through capillary channels.
6. A device according to claim 1 , made from a material selected from the group consisting of: Nitinol; silicon composite; a superelastic material; a metal; a plastic; a ceramic; and a composite material.
7. A device according to claim 1 , wherein the barbs have a barb penetration into the plaque and/or vessel walls in the range of about 0.2 to 5 millimeters.