PUNCTURABLE AND RESEALABLE GRAFT
Implantable grafts, particularly for arteriovenous access that may be punctured by an object such as a needle and, following removal of the object, will reseal the resulting hole to the extent of reducing fluid leakage through the graft at the puncture site to an amount less than would be typical for a conventional graft. More particularly, the grafts comprise three layers; an inner layer of implantable graft material such as ePTFE, a middle layer of self sealing elastomeric material such as silicone, and an outer layer of implantable graft material such as ePTFE. Following manufacture, the tubular form of the three-layer graft is everted to put substantially the entire wall thickness of the elastomeric material layer under circumferential compression.
1 . An implantable stent-graft having a diametrically compacted, insertion profile and a diametrically expanded, deployed profile, the stent-graft comprising:
a stent having a tubular shape; and
a graft secured to the stent, the graft including,
an outer tubular member formed of a graft material, the outer tubular member defining an inner surface, an outer surface, and a thickness between the inner and outer surfaces, an entirety of the thickness being under circumferential tension;
an inner tubular member formed of a graft material, the inner tubular member defining an inner surface, an outer surface, and a thickness between the inner and outer surfaces, an entirety of the thickness of the inner tubular member being under radial compression by the outer tubular member; and
an elastomeric coating between the inner and outer tubular members, an entirety of the thickness of the elastomeric coating being under radial compression by the outer tubular member.
2 . The stent-graft of claim 1 , wherein the insertion profile corresponds to a maximum diameter of about 13 French.
3 . The stent-graft of claim 1 , wherein the stent is configured as a self-expanding stent.
4 . The stent-graft of claim 1 , wherein the stent is configured as a balloon expandable stent.
5 . The stent-graft of claim 1 , wherein the graft material of the inner tubular member includes ePTFE material.
6 . The stent-graft of claim 1 , wherein the graft material of the outer tubular member includes ePTFE material.
7 . The stent-graft of claim 1 , wherein the elastomeric coating include silicone material.
8 . The stent-graft of claim 1 , wherein the elastomeric coating includes a fluroelastomer material.
9 . The stent-graft of claim 1 , wherein the elastomeric material is a copolymer of tetrafluoroethylene and polyalkylvinylether.
10 . The stent-graft of claim 1 , wherein the elastomeric material is a polyurethane.
11 . The stent-graft of claim 1 , wherein the thickness of the graft has an overall wall thickness of less than about 0.40 mm.
12 . The stent-graft of claim 1 , having a puncture characteristic that includes leakage of the graft stopping entirely after about 2 seconds after being punctured with a 16 gauge dialysis needle at an angle of about 45 degrees while pressurized with room temperature water at 2.5 psi (17.2 KPa).
13 . An implantable stent-graft having a diametrically compacted, insertion profile and a diametrically expanded, deployed profile, the stent-graft comprising:
a stent having a tubular shape; and
a graft secured to the stent, the graft including,
an outer tubular member formed of a graft material, the outer tubular member defining an inner surface, an outer surface, and a thickness between the inner and outer surfaces, an entirety of the thickness being under circumferential tension;
an inner tubular member formed of a graft material, the inner tubular member defining an inner surface, an outer surface, and a thickness between the inner and outer surfaces, an entirety of the thickness of the inner tubular member being under radial compression by the outer tubular member; and
an elastomeric coating between the inner and outer tubular members, the elastomeric coating including a first layer made of a first elastomeric material and a second layer made of a second elastomeric material, an entirety of a thickness of the elastomeric coating being under radial compression by the outer tubular member;
wherein the first elastomeric material is different than the second elastomeric material.
14 . The stent-graft of claim 13 , wherein the first elastomeric material is selected from a group consisting of: a silicone material, a fluroelastomer material, a copolymer of tetrafluoroethylene and polyalkylvinylether, and a polyurethane.
15 . The stent-graft of claim 14 , wherein the second elastomeric material is selected from a group consisting of: a silicone material, a fluroelastomer material, a copolymer of tetrafluoroethylene and polyalkylvinylether, and a polyurethane.
16 . An implantable stent-graft having a diametrically compacted, insertion profile and a diametrically expanded, deployed profile, the stent-graft comprising:
a stent having a tubular shape; and
a graft secured to the stent, the graft including,
an outer tubular member formed of a graft material, the outer tubular member defining an inner surface, an outer surface, and a thickness between the inner and outer surfaces, an entirety of the thickness being under circumferential tension;
an inner tubular member formed of a graft material, the inner tubular member defining an inner surface, an outer surface, and a thickness between the inner and outer surfaces, an entirety of the thickness of the inner tubular member being under radial compression by the outer tubular member; and
an elastomeric coating between the inner and outer tubular members, the elastomeric coating including a first layer and a second layer, the first layer abluminal to the second layer, an entirety of a thickness of the elastomeric coating being under radial compression by the outer tubular member;
wherein the first layer is under a first amount of radial compression, and the second layer is under a second amount of radial compression that is greater than the first amount of radial compression.
17 . The stent-graft of claim 16 , wherein the first amount of radial compression is a minimum amount of radial compression by the outer tubular member and the second amount of radial compression is a maximum amount of radial compression by the outer tubular member.
18 . The stent-graft of claim 16 , wherein the first amount of radial compression is zero.
19 . The stent-graft of claim 16 , wherein the first layer is made of a first material selected from a group consisting of: a silicone material, a fluroelastomer material, a copolymer of tetrafluoroethylene and polyalkylvinylether, and a polyurethane.
20 . The stent-graft of claim 19 , wherein the second layer is made of a second material selected from a group consisting of: a silicone material, a fluroelastomer material, a copolymer of tetrafluoroethylene and polyalkylvinylether, and a polyurethane.