COMPOSITE PROSTHETIC SHUNT DEVICE
In accordance with certain embodiments of the present disclosure, a composite prosthetic device is described. Generally, the device comprises at least one layer of ePTFE, at least one thermoplastic elastomeric component, and a frame. In certain aspects, the thermoplastic elastomeric component penetrates the microstructure of the at least one layer of ePTFE, providing a means for varying the porosity of the ePTFE.
1 . A composite prosthetic shunt comprising:
an inner lumen;
a first tubular layer of expanded polytetrafluoroethylene (ePTFE) having nodes and fibrils around the inner lumen;
a tubular frame imbedded in polyurethane positioned around and overlying the first tubular layer of ePTFE; and
a second tubular layer of ePTFE having nodes and fibrils positioned around and overlying the tubular frame imbedded in polyurethane;
wherein the polyurethane penetrates at least about 50% of the spaces between the nodes and fibrils of at least one of the first and second tubular layers of ePTFE.
2 . The composite prosthetic shunt of claim 1 , wherein the average cross-sectional thickness of the shunt wall is between about 0.25 mm and 0.51 mm.
3 . The composite prosthetic shunt of claim 1 , wherein the shunt walls exhibit an average porosity of less than about 20%.
4 . The composite prosthetic shunt of claim 1 , wherein the shunt walls exhibit an average porosity of about 0%.
5 . The composite prosthetic shunt of claim 1 , wherein the polyurethane penetrates at least about 50% of the spaces between the nodes and fibrils of both the first and second tubular layers of ePTFE.
6 . The composite prosthetic shunt of claim 1 , wherein the polyurethane penetrates at least about 80% of the spaces between the nodes and fibrils of at least one of the first and second tubular layers of ePTFE.
7 . The composite prosthetic shunt of claim 1 , wherein the polyurethane penetrates at least about 80% of the spaces between the nodes and fibrils of both the first and second tubular layers of ePTFE.
8 . The composite prosthetic shunt of claim 1 , wherein the shunt exhibits a radial force such that after the shunt is compressed to close the inner lumen for 48 hours, the shunt fully reopens when the compression is removed.
9 . The composite prosthetic shunt of claim 1 , wherein the shunt exhibits an opening force of greater than about 200 grams.
10 . The composite prosthetic shunt of claim 1 , wherein the shunt exhibits an opening force of about 200 to about 300 grams.
11 . The composite prosthetic shunt of claim 1 , wherein the shunt exhibits no substantial decrease in performance after being compressed to close the inner lumen and then opened about 2,000 times or more.
12 . The composite prosthetic shunt of claim 1 , wherein the shunt exhibits no substantial decrease in performance after being compressed to close the inner lumen and then opened about 3,000 times or more.
13 . The composite prosthetic shunt of claim 11 , wherein the no substantial decrease in performance is evidenced by one or more of: no significant change in inside or outside dimensions of the shunt; no observable wear or deformation; no significant change in the recovery force of the shunt; and no significant loss of particulate material from the shunt.
14 . The composite prosthetic shunt of claim 12 , wherein the no substantial decrease in performance is evidenced by one or more of: no significant change in inside or outside dimensions of the shunt; no observable wear or deformation; no significant change in the recovery force of the shunt; and no significant loss of particulate material from the shunt.
15 . A hemoaccess valve system comprising the composite prosthetic shunt of claim 1 .
16 . A method for making a composite prosthetic shunt, comprising:
applying a polyurethane sheet or tube to a construct comprising a tubular frame overlying a first ePTFE tubular structure;
applying a second ePTFE tubular structure overlying polyurethane sheet or tube to form a layered composite;
compressing the layered composite; and
heating the layered composite such that the polyurethane penetrates at least about 50% of the spaces between the nodes and fibrils of at least one of the first and second tubular layers of ePTFE.
17 . The method of claim 16 , wherein the compressing and heating steps are conducted at the same time.
18 . The method of claim 16 , wherein the heating is conducted at a temperature at or above the melting temperature of the polyurethane.
19 . The method of claim 16 , wherein the compressing step comprises wrapping the layered composite with a compression wrap.