Claims
- 1. A method of forming a vascular prosthetic structure having a bloodstream interface, the method comprising the steps of:
- A. mixing polytetrafluoroethylene resin with a thromboresistance imparting amount of graphite powder to create a substantially homogeneous mixture;
- B. compacting the mixture and forming a preform including the mixture;
- C. extruding the preform to form an extrudate;
- D. expanding the extrudate to form an expanded structure having a plurality of spaced nodes interconnected by fibrils;
- E. sintering the expanded structure while restraining the expanded structure against contraction, to form the vascular prosthetic structure, whereby graphite is incorporated in the expanded structure in a thromboresisting amount at least at the bloodstream interfaces; and
- F. sterilizing the vascular prosthetic structure.
- 2. The method of forming a vascular prosthetic structure recited in claim 1, wherein step A includes mixing the resin and the powder so that a ratio of polytetrafluoroethylene to graphite is from about 5:1 to 15:1 by weight.
- 3. The method of forming a vascular prosthetic structure recited in claim 1, wherein step A includes mixing the resin and the powder so that a ratio of polytetrafluoroethylene to graphite is about 9:1 by weight.
- 4. The method of claim 1, wherein the vascular prosthetic structure is a tubular vascular graft, and wherein step C includes a step of extruding the preform to form a tubular extrudate.
- 5. The method of claim 2, wherein the vascular prosthetic structure is a tubular vascular graft, and wherein step C includes a step of extruding the preform to form a tubular extrudate.
- 6. The method of claim 3, wherein the vascular prosthetic structure is a tubular vascular graft, and wherein step C includes a step of extruding the preform to form a tubular extrudate.
- 7. The method recited in claim 1, further including a step of implanting the vascular prosthetic structure in a human body.
- 8. The method recited in claim 2, further including a step of implanting the vascular prosthetic structure in a human body.
- 9. The method recited in claim 3, further including a step of implanting the vascular prosthetic structure in a human body.
- 10. The method recited in claim 4, further including a step of implanting the vascular prosthetic structure in a human body.
Parent Case Info
This application is a continuation of application Ser. No. 08/230,602, filed Apr. 21, 1994, entitled GRAPHITE IMPREGNATED PROSTHETIC VASCULAR GRAFT MATERIALS, now abandoned, which is a continuation of application Ser. No. 07/920,124, filed Jul. 24, 1992, which is a continuation of application Ser. No. 07/799,385 filed Nov. 27, 1991 now abandoned, which is a continuation of application Ser. No. 07/648,204 filed Jan. 31, 1991, now abandoned, which is a continuation of application Ser. No. 07/537,341 filed Jun. 13, 1990, now abandoned, which is a continuation of application Ser. No. 07/432,038 filed Nov. 3, 1989, now abandoned, which is a continuation of application Ser. No. 07/328,569 filed Mar. 27, 1989, now abandoned, which is a continuation of application Ser. No. 07/174,588 filed Mar. 29, 1988, now abandoned, which is a continuation of application Ser. No. 07/081,659 filed Aug. 4, 1987, now abandoned, which is a continuation of application Ser. No. 06/908,995 filed Sep. 18, 1986, now abandoned, which is a continuation of application Ser. No. 06/807,834 filed Dec. 11, 1985, now abandoned which is a continuation of application Ser. No. 06/726,140 filed Apr. 23, 1985, now abandoned, which is a continuation of application Ser. No. 06/633,143 filed Jul. 23, 1984, now abandoned, which is a continuation of application Ser. No. 06/467,872 filed Feb. 18, 1983, now abandoned, which is a continuation of application Ser. No. 06/292,906 filed Aug. 14, 1981, now abandoned, which is a continuation of application Ser. No. 06/136,693 filed Apr. 2, 1980, now abandoned, which is a continuation of application Ser. No. 05/862,826 filed on Dec. 21, 1977, now abandoned, which is a continuation-in-part of application Ser. No. 05/517,415 filed on Oct. 24, 1974.
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Foreign Referenced Citations (1)
Number |
Date |
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686438 |
Jan 1953 |
GBX |
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Soyer et al., A New Venous Prosthesis, Surgery, 72:864, 1972. |
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Continuations (17)
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230602 |
Apr 1994 |
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920124 |
Jul 1992 |
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799385 |
Nov 1991 |
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648204 |
Jan 1991 |
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537341 |
Jun 1990 |
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432038 |
Nov 1989 |
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328569 |
Mar 1989 |
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174588 |
Mar 1988 |
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081659 |
Aug 1987 |
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908995 |
Sep 1986 |
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807834 |
Dec 1985 |
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726140 |
Apr 1985 |
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633143 |
Jul 1984 |
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467872 |
Feb 1983 |
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292906 |
Aug 1981 |
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136693 |
Apr 1980 |
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862816 |
Dec 1977 |
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Continuation in Parts (1)
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517415 |
Oct 1974 |
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