Patent US4265694A successfully refreshed from Google Patents.
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
•
Filing: 1980-01-22
•
Granted: 1981-05-05
•
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 18:38
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.
References Cited (Backward Citations)
US2662724A
Cited
US3320972A
Cited
US3445916A
Cited
US3548417A
Cited
US3755823A
Cited
US3744062A
Cited
US3940802A
Cited
US4172295A
Cited
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 |