US4657544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cardiovascular graft and method of forming same
Assignee: Lifeshield Sciences LLC
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Filing: 1984-04-18
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Granted: 1987-04-14
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Expires: 2004-04-18
Abstract
Abstract The graft is particularly adapted for cardiovascular use and comprises a tube which has been reaction injection molded, cast molded, or extruded from a nonsolvent, two component hydrophobic biocompatible polymer system, which is initially formed with water soluble inorganic salt crystals mixed with the system, and which has a honeycomb of interconnecting cells throughout the thickness of the wall of the tube formed by the leaching of the water soluble inorganic salt crystals from the tube.
Inventors
- 👤 Leonard Pinchuk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:50
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/26; A; A61; A61F; A61F2/00; A61F2/02; A61F2/04; A61F2/06; A61L; A61L27/00; A61L27/14; A61L27/16; A61L27/18; A61L27/50; A61L27/507; A61L27/56; C08J9/24; C08L; C08L27/00; C08L27/02; C08L27/12; C08L27/18; C08L75/00; C08L75/04; C08L83/00; C08L83/04; B; B29; B29C; B29C45/00; B29C45/17; B29C45/1703; B29C45/1704; B29C2045/1719; B29K; B29K2995/00; B29K2995/0037; B29K2995/0056; B29L; B29L2023/00; B29L2023/005; B29L2023/007; B29L2031/00; B29L2031/753; B29L2031/7532; B29L2031/7534
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
76 words
A graft particularly adapted for cardiovascular use, said graft comprising a tube which has been reaction injection molded, cast molded, or extruded from a nonsolvent, two component hydrophobic biocompatible polymer system, which is initially formed with water soluble inorganic salt crystals mixed with the system, and which has a honeycomb of interconnecting cells throughout the thickness of the wall of the tube formed by the leaching of said water soluble inorganic salt crystals from the tube.
Claim 2
Dependent Claim
76 words
A graft particularly adapted for cardiovascular use, said graft comprising a tube which has been reaction injection molded, cast molded, or extruded from a nonsolvent, two component hydrophobic biocompatible polymer system, which is initially formed with water soluble inorganic salt crystals mixed with the system, and which has a honeycomb of interconnecting cells throughout the thickness of the wall of the tube formed by the leaching of said water soluble inorganic salt crystals from the tube.
Claim 3
Dependent Claim
17 words
The graft of claim 1 wherein the biocompatible polymer system is a polymer resin and curing agent.
Claim 4
Dependent Claim
20 words
The graft of claim 2 wherein said polymer resin is chosen from the group comprising polyurethane, silicone and polytetrafluoroethylene (Teflon).
Claim 5
Dependent Claim
25 words
The graft of claim 2 wherein said curing agent is chosen from the group comprising platinum, tempered steel heat, cross linkers, gamma radiation and ureaformaldehyde.
Claim 6
Dependent Claim
21 words
The graft of claim 1 wherein said inorganic salt crystals are sized to provide cells in the tube of predetermined size.
Claim 7
Dependent Claim
14 words
The graft of claim 5 wherein said inorganic salt crystals are sodium chloride crystals.
Claim 8
Dependent Claim
31 words
The graft of claim 1 wherein said inorganic salt crystals are dried crystals which have been dried at a temperature between 100° and 175° C. for a minimum of twenty-four hours.
Claim 9
Dependent Claim
12 words
The graft of claim 7 wherein said temperature is approximately 135° C.
Claim 10
Dependent Claim
13 words
The graft of claim 1 wherein said crystals have a predetermined mesh size.
Claim 11
Dependent Claim
16 words
The graft of claim 9 wherein said mesh size is between approximately 10 and 200 microns.
Claim 12
Dependent Claim
33 words
The graft of claim 1 wherein the concentration of water soluble inorganic salt crystals relative to said biocompatible polymer system in the initially formed tube is between approximately 25% and 75% by weight.
Claim 13
Dependent Claim
22 words
The graft of claim 11 wherein said range is determined by the required flexibility and/or porosity of the graft to be fabricated.
Claim 14
Dependent Claim
16 words
The graft of claim 1 wherein said cells are of a uniform diameter within the graft.
Claim 15
Dependent Claim
21 words
The graft of claim 13 wherein the diameter of the cells in the graft is between approximately 10 and 200 microns.
Claim 16
Dependent Claim
36 words
The graft of claim 1 wherein the wall thickness of the graft is between approximately 0.5 cm and 4 cm depending on the location at which the graft is to be used within the cardiovascular system.
Claim 17
Dependent Claim
35 words
The graft of claim 1 wherein the concentration of water soluble inorganic salt crystals relative to said biocompatible polymer system in the initially formed tube is greater than 50% but less than 90% by weight.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-13 | 1990-10-13 | 1991-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-13 | 1994-10-13 | 1995-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-13 | 1998-10-13 | 1999-04-14 | $7700.00 | Window Closed / Lapsed |