Expandable shielded vessel support
First Claim
1. A method of fabricating a stent, comprising the steps of;
- positioning a tube formed of a polymer material within a stent body, the polymer tube having a first end and a second end;
folding the first end of the polymer tube over a first end of the stent body to form a first cuff enclosing the first end of the stent body;
folding the second end of the polymer tube over a second end of the stent body to form a second cuff enclosing the second end of the stent body and extending an amount at least sufficient to meet an end of said first cuff; and
coalescing the polymer tube to seal the first end of the stent body within the first cuff and the second end of the stent body within the second cuff such that said stent body is completely enclosed within a seamless cocoon of said polymer material.
1 Assignment
0 Petitions
Accused Products
Abstract
A radially expandable support body is enveloped within a cocoon. In a preferred construction, the support is a stent, and a tube of polymeric material, e.g., polytetraeluoroethylene (PTFE), passes through the interior of the stent body and is turned back upon itself over the stent to form a cuff. The assembly is then heated and the outer layer contacts and coalesces with the inner layer, closely surrounding the stent body within a folded envelope having a continuous and seamless end. In one embodiment, an end portion of the tube is expanded before folding back over the-stent. The end portion, which becomes an exterior surface of the finished product, thus acquires a greater degree of porosity. Each end of the central tube may be so expanded, and folded back to seal all surfaces and both ends. The stent body itself may be a ring, or a short series of spaced-apart rings, or a wire or web, or a sheet possessing a number of apertures extending entirely through the sheet. The spaces or apertures are covered over or bridged by both the inner and outer polymer layers. The apertures, which may comprise under five to over eighty percent of the surface area of the stent, constitute regions or a grid of points through which the material is coalesced and continuously bonded, and around which strain is distributed by the support. These points or regions remain tacked together so expansion of the assembly does not delaminate the polymer or create flaps and pockets. In another embodiment, a two tube construction is cuffed and assembled into a similarly unitized and seamless stent. One tube is cuffed back, and the other tube covers the cuffed stent. In this embodiment both the tube thicknesses and porosities may differ substantially. For example the inner porosity may be selected to enhance blood flow or intimal regeneration, and the outer surface may have a porosity to encourage anchoring to external muscle tissue.
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Citations
39 Claims
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1. A method of fabricating a stent, comprising the steps of;
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positioning a tube formed of a polymer material within a stent body, the polymer tube having a first end and a second end;
folding the first end of the polymer tube over a first end of the stent body to form a first cuff enclosing the first end of the stent body;
folding the second end of the polymer tube over a second end of the stent body to form a second cuff enclosing the second end of the stent body and extending an amount at least sufficient to meet an end of said first cuff; and
coalescing the polymer tube to seal the first end of the stent body within the first cuff and the second end of the stent body within the second cuff such that said stent body is completely enclosed within a seamless cocoon of said polymer material. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
wrapping a layer of polymer material about the stent body. -
19. The method of claim 18, wherein the first cuff encloses a first end of the layer and the second cuff encloses a second end of the layer.
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20. The method of claim 18, further comprising coalescing the layer to the polymer tube.
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21. A method of fabricating a stent, comprising the steps of;
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positioning a tube formed of radially expandable polymer within a stent body, the polymer tube having a first end and a second end;
folding the first end of the polymer tube over a first end of the stent body to form a first cuff enclosing the first end of the stent body;
folding the second end of the polymer tube over a second end of the stent body and over the first cuff to form a second cuff enclosing the second end of the stent body; and
coalescing the polymer tube to seal the first end of the stent body within the first cuff and the second end of the stent body within the second cuff such that said stent body is completely enclosed within a seamless cocoon of said polymer material.
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22. A stent comprising:
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a radially expandable member; and
a polymer tube having first and second ends, a portion of the polymer tube being positioned within the radially expandable member, the first end of the polymer tube being folded over a first end of the radially expandable member to form a first cuff, the first end of the polymer tube being coalesced to the portion of the polymer tube within the radially expandable member to enclose the first end of the radially expandable member within the first cuff, the second end of the tube being folded over a second end of the radially expandable member extending an amount at least sufficient to meet an end of said first cuff to form a second cuff, the second end of the polymer tube being coalesced to the portion of the polymer tube within the radially expandable member to enclose the second end of the radially expandable member within the second cuff such that said stent body is completely enclosed within a seamless cocoon of said polymer material. - View Dependent Claims (23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
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Specification