US4265694A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making unitized three leaflet heart valve
Assignee: United States Department of Health and Human Services
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Filing: 1980-01-22
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Granted: 1981-05-05
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Expires: 2000-01-22
Abstract
Abstract An artificial heart valve comprising a semi-rigid framework having three projecting symmetrical struts and open axially therethrough, as well as a polyurethane elastomeric membrane attached to the struts and constituting three leaflets, is formed by molding the framework, including the base and strut, using polyurethane resin; forming the elastomeric membrane, of polyurethane resin which is thin relative to the framework, and forming a thickened commissure along the leading edge of the membrane as well as reinforcing lines radiating from its base; then joining the framework with the elastomeric membrane using an adhesive cement so as to permanently bond the membrane to the framework.
Inventors
- 👤 John W. Boretos
- 👤 Norio Iriguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:12
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/14; F16K15/144; F16K15/147; A; A61; A61F; A61F2/00; A61F2/02; A61F2/24; A61F2/2412; B; B29; B29C; B29C41/00; B29C41/02; B29C41/14; Y; Y10; Y10S; Y10S623/00; Y10S623/901
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
87 words
A method of producing an artificial heart valve, comprising the steps of: molding an artificial heart framework, including a base and struts, using polyurethane resin; forming an elastomeric membrane, of polyurethane resin which is thin relative to said framework, and forming a thickened commissure along the leading edge of said membrane, and forming a plurality of lines, thicker than said membrane, radiating from the base of said membrane; joining said framework with said elastomeric membrane using an adhesive cement, and permanently bonding said membrane to said framework.
Claim 2
Independent Claim
87 words
A method of producing an artificial heart valve, comprising the steps of: molding an artificial heart framework, including a base and struts, using polyurethane resin; forming an elastomeric membrane, of polyurethane resin which is thin relative to said framework, and forming a thickened commissure along the leading edge of said membrane, and forming a plurality of lines, thicker than said membrane, radiating from the base of said membrane; joining said framework with said elastomeric membrane using an adhesive cement, and permanently bonding said membrane to said framework.
Claim 3
Dependent Claim
24 words
A method according to claim 1, further comprising permanently bonding a suture ring to the base of said framework using solvent or adhesive cement.
Claim 4
Independent Claim
206 words
A method of producing an artificial heart valve, comprising the steps of: injection molding a framework using polyurethane, including a base and struts of the heart valve; annealing said framework for relieving residual strains in said framework; forming an elastomeric membrane having a base and a commissure area, of polyurethane thin relative to said framework, by solvent casting, using a first mandrel, and reinforcing the commissure area by building up a lip, thick relative to the thickness of said membrane, along the leading edge of said membrane, and forming a plurality of lines, thicker than said membrane, radiating from the base of said membrane; drying said membrane to remove solvent therefrom; peeling said membrane from said first mandrel; orienting said framework over a second mandrel having a trileaflet design and coating said membrane with a polyurethane solvent; placing said membrane over said second mandrel, on said framework; applying solvent or adhesive cement, and pressure to a bond line between said membrane and said framework, until said membrane and framework are permanently bonded together; removing said framework and membrane from said second mandrel; permanently bonding a suture ring to the base of said framework using solvent or adhesive cement; and drying the valve to remove said solvent
Claim 5
Independent Claim
206 words
A method of producing an artificial heart valve, comprising the steps of: injection molding a framework using polyurethane, including a base and struts of the heart valve; annealing said framework for relieving residual strains in said framework; forming an elastomeric membrane having a base and a commissure area, of polyurethane thin relative to said framework, by solvent casting, using a first mandrel, and reinforcing the commissure area by building up a lip, thick relative to the thickness of said membrane, along the leading edge of said membrane, and forming a plurality of lines, thicker than said membrane, radiating from the base of said membrane; drying said membrane to remove solvent therefrom; peeling said membrane from said first mandrel; orienting said framework over a second mandrel having a trileaflet design and coating said membrane with a polyurethane solvent; placing said membrane over said second mandrel, on said framework; applying solvent or adhesive cement, and pressure to a bond line between said membrane and said framework, until said membrane and framework are permanently bonded together; removing said framework and membrane from said second mandrel; permanently bonding a suture ring to the base of said framework using solvent or adhesive cement; and drying the valve to remove said solvent
Claim 6
Dependent Claim
18 words
A method, according to claim 3, wherein said membrane and the completed valve are dried at 50° C.
Claim 7
Dependent Claim
33 words
A method, according to claim 3, wherein the pressure applied to the boundary between said membrane and said framework is 15ps: for 5 minutes to one hour at between 240° and 320° F.
Claim 8
Dependent Claim
59 words
A method, according to claim 3, wherein said step of forming said elastomeric membrane by solvent casting comprises; forming a solution containing polyurethane and a solvent; removing all the air from said solution; dipping a first mandrel in said solution at least once; withdrawing said first mandrel from said solution so as to preclude trapping air in said solution.
Claim 9
Dependent Claim
25 words
A method, according to claim 3, further including; removing all the air from the injection molded parts before said framework is formed by injection molding.
Claim 10
Dependent Claim
24 words
A method, according to claim 3, wherein said annealing takes place at between 200° F. and 300° F. for between 1 and 24 hours.
Claim 11
Dependent Claim
17 words
A method, according to claim 6, wherein said solvent is dimethyl acetamide, tetrahydrofuran, dimethly formamide or cyclohexanone.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-05-04 | 1984-11-03 | 1985-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-04 | 1988-11-03 | 1989-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-04 | 1992-11-03 | 1993-05-05 | $7700.00 | Window Closed / Lapsed |