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US6245105B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Method of testing bioprosthetic heart valve leaflets

Assignee: Edwards Lifesciences Corp
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Filing: 1998-12-09
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Granted: 2001-06-12
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Expires: 2018-12-09
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Abstract

Abstract Heart valve leaflet selection methods and apparatuses which subject individual leaflets to loads and measure the resulting deflection to more reliably group leaflets of similar physical characteristics for later assembly in prosthetic heart valves. The deflection testing may be accomplished using a variety of test set ups which are designed to impart a load on the leaflet which simulates the actual loading within a heart valve. The results from a number of deflection tests are used to categorize individual leaflets, which data can be combined with other data regarding the characteristics of the leaflet to better select leaflets for assembly into a multi-leaflet heart valve. In one embodiment, the deflection test is combined with an intrinsic load test, and leaflets having similar deflection and intrinsic load values used in the same heart valve. One apparatus for testing the leaflets includes a frame for securing the arcuate cusp of the leaflet while the straight coapting edge remains free, to simulate the actual leaflet mounting configuration within the heart valve prosthesis. The frame may include a lower portion having a recess for the leaflet and plurality of receptor holes around the peripheral edge of the recess, and an upper portion having a plurality of needles which extend downward through the leaflet and into the receptor holes and secure the edges of the leaflet.

Inventors

  • 👤 Than Nguyen
  • 👤 Hung Ly Lam
  • 👤 Jianbo Zhou
  • 👤 Carlos M. Romero
  • 👤 Ralph Kafesjian
  • 👤 Xiaoming G. Guo
  • 👤 Van Le Huynh

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:51
CPC Classifications
A; A61; A61M; A61M25/00; A61M25/01; A61M25/0105; A61M25/0133; A61F; A61F2/00; A61F2/02; A61F2/24; A61F2/2412; A61F2/2415; A61F2/2472; Y; Y10; Y10S; Y10S623/00; Y10S623/90; Y10S623/909; Y10S623/91; Y10S623/912; Y10S623/913

Claims Analysis

Total Claims: 44
Claim 1
Independent Claim 48 words
A method of selecting leaflets for an implantable heart valve, comprising the steps of: providing a collection of similarly sized leaflets; applying a load to each leaflet; observing the strain response in each leaflet from applying the load; and sorting the leaflets based on their respective strain responses.
Claim 2
Independent Claim 48 words
A method of selecting leaflets for an implantable heart valve, comprising the steps of: providing a collection of similarly sized leaflets; applying a load to each leaflet; observing the strain response in each leaflet from applying the load; and sorting the leaflets based on their respective strain responses.
Claim 3
Dependent Claim 21 words
The method of claim 1 , wherein the step of providing a collection includes providing a collection of natural tissue leaflets.
Claim 4
Dependent Claim 18 words
The method of claim 2 , further including the step of chemically fixing the leaflets prior to testing.
Claim 5
Dependent Claim 25 words
The method of claim 2 , wherein the step of providing a collection of natural tissue leaflets includes providing a collection of bovine pericardium leaflets.
Claim 6
Dependent Claim 28 words
The method of claim 1 , wherein the step of providing a collection of leaflets includes providing a collection of leaflets having a matrix and natural tissue ingrowth.
Claim 7
Dependent Claim 32 words
The method of claim 1 , wherein the step of providing a collection of leaflets includes providing a collection of leaflets having a substrate on which is formed a cell growth covering.
Claim 8
Dependent Claim 23 words
The method of claim 1 , wherein the step of providing a collection of leaflets includes providing a collection of extruded collagen leaflets.
Claim 9
Dependent Claim 45 words
The method of claim 1 , wherein the step of applying a load comprises applying a load sufficient to create an average stress in at least some of the leaflets within a generally linear, high modulus region of a stress/strain curve of the leaflet material.
Claim 10
Dependent Claim 26 words
The method of claim 1 , further including the step of applying a load for a predetermined number of times prior to observing the strain response.
Claim 11
Dependent Claim 14 words
The method of claim 9 , wherein the predetermined number is at least three.
Claim 12
Dependent Claim 30 words
The method of claim 1 , further including the steps of: performing an intrinsic load test on the leaflets; and sorting the leaflets based on the intrinsic load test results.
Claim 13
Dependent Claim 26 words
The method of claim 1 , wherein the step of sorting the leaflets comprises forming subgroups of leaflets having a strain response within a predetermined range.
Claim 14
Dependent Claim 53 words
The method of claim 12 , wherein the step of forming subgroups of leaflets having a strain response within a predetermined range comprises a measuring a deflection of each leaflet resulting from applying a load thereto, and forming a subgroup of leaflets each having a deflection within about 0.030 inches of the others.
Claim 15
Independent Claim 177 words
A method of testing a leaflet for use in an implantable heart valve, comprising the steps of: mounting the leaflet in a framing assembly so that portions which are to be sutured in the valve are held stationary, wherein the leaflet defines a cusp edge and a coapted edge generally opposite the cusp edge, and the framing assembly includes an upper member and a lower member, the lower member having a recess for receiving at least the cusp edge of the leaflet, the upper member being shaped to mate over the recess, and the framing assembly defining a cavity circumscribed by the recess, the step of mounting including positioning the leaflet in the recess and piercing the leaflet cusp edge with needles extending between and supported from movement by the upper and lower members, to hold at least the cusp edge of the leaflet stationary; applying a load to the leaflet in a location adapted to simulate a point at which an average load is applied in the valve; and sensing the resulting strain in the leaflet.
Claim 16
Independent Claim 177 words
A method of testing a leaflet for use in an implantable heart valve, comprising the steps of: mounting the leaflet in a framing assembly so that portions which are to be sutured in the valve are held stationary, wherein the leaflet defines a cusp edge and a coapted edge generally opposite the cusp edge, and the framing assembly includes an upper member and a lower member, the lower member having a recess for receiving at least the cusp edge of the leaflet, the upper member being shaped to mate over the recess, and the framing assembly defining a cavity circumscribed by the recess, the step of mounting including positioning the leaflet in the recess and piercing the leaflet cusp edge with needles extending between and supported from movement by the upper and lower members, to hold at least the cusp edge of the leaflet stationary; applying a load to the leaflet in a location adapted to simulate a point at which an average load is applied in the valve; and sensing the resulting strain in the leaflet.
Claim 17
Dependent Claim 27 words
The method of claim 14 , wherein the leaflet is made of natural tissue and further including the step of chemically fixing the leaflet prior to testing.
Claim 18
Dependent Claim 28 words
The method of claim 14 , wherein the step of applying a load comprises applying a mechanical deflector to an upper surface of the leaflet over the cavity.
Claim 19
Dependent Claim 15 words
The method of claim 14 , further including the step of recording the sensed strain.
Claim 20
Dependent Claim 19 words
The method of claim 17 , further including applying a load at least twice before recording the sensed strain.
Claim 21
Dependent Claim 25 words
The method of claim 14 , further including testing a second leaflet and correlating the results of the applied load tests for the two leaflets.
Claim 22
Dependent Claim 40 words
The method of claim 14 , further including the step of performing a droop test on the leaflet by extending the leaflet over the end of a structure, and observing the resulting droop of the extended end of the leaflet.
Claim 23
Dependent Claim 28 words
The method of claim 20 , further including testing a second leaflet and correlating the results of the droop tests and applied load tests for the two leaflets.
Claim 24
Dependent Claim 46 words
The method of claim 14 , wherein the leaflet is made of a leaflet material, and the step of applying a load comprises applying a load sufficient to stress the leaflet within a generally linear high modulus region of a stress/strain curve of the leaflet material.
Claim 25
Dependent Claim 27 words
The method of claim 14 , wherein the step of applying a load comprises applying a load sufficient to stress the leaflet between 300 and 600 kPa.
Claim 26
Dependent Claim 39 words
The method of claim 14 , wherein the location at which the load is applied comprises an idealized concentrated load point and the step of applying a load comprises applying a load to a distributed area of the leaflet.
Claim 27
Dependent Claim 18 words
The method of claim 14 , wherein the leaflet is made of a matrix and natural tissue ingrowth.
Claim 28
Dependent Claim 22 words
The method of claim 14 , wherein the leaflet is made of a substrate on which is formed a cell growth covering.
Claim 29
Dependent Claim 14 words
The method of claim 14 , wherein the leaflet is made of extruded collagen.
Claim 30
Independent Claim 146 words
A method of testing a leaflet for use in an implantable heart valve, wherein the leaflet defines a cusp edge and a coapting edge generally opposite the cusp edge, comprising the steps of: positioning the leaflet in a frame assembly including an upper member and a lower member, the lower member having a recess for receiving and securing the cusp edge of the leaflet the user member being shaped to mate over the recess, and the framing assembly further defining a cavity circumscribed by the recess; supporting the leaflet by piercing the leaflet cusp edge with needles extending between and supported from movement by the upper and lower members to hold at least the cusp edge of the leaflet stationary such that a mid-portion remains unsupported; applying a load to the mid-portion of the leaflet; and sensing the resulting strain at the mid-portion of the leaflet.
Claim 31
Independent Claim 146 words
A method of testing a leaflet for use in an implantable heart valve, wherein the leaflet defines a cusp edge and a coapting edge generally opposite the cusp edge, comprising the steps of: positioning the leaflet in a frame assembly including an upper member and a lower member, the lower member having a recess for receiving and securing the cusp edge of the leaflet the user member being shaped to mate over the recess, and the framing assembly further defining a cavity circumscribed by the recess; supporting the leaflet by piercing the leaflet cusp edge with needles extending between and supported from movement by the upper and lower members to hold at least the cusp edge of the leaflet stationary such that a mid-portion remains unsupported; applying a load to the mid-portion of the leaflet; and sensing the resulting strain at the mid-portion of the leaflet.
Claim 32
Dependent Claim 27 words
The method of claim 28 , wherein the leaflet is made of natural tissue and further including the step of chemically fixing the leaflet prior to testing.
Claim 33
Dependent Claim 27 words
The method of claim 28 , wherein the stop of applying a load comprises applying a mechanical deflector to the mid-point of the leaflet over the cavity.
Claim 34
Dependent Claim 15 words
The method of claim 28 , further including the step of recording the sensed strain.
Claim 35
Dependent Claim 22 words
The method of claim 31 , further including applying the load at least twice to the leaflet before recording the sensed strain.
Claim 36
Dependent Claim 25 words
The method of claim 28 , further including testing a second leaflet and correlating the results of the applied load tests for the two leaflets.
Claim 37
Dependent Claim 40 words
The method of claim 28 , further including the step of performing a droop test on the leaflet by extending the leaflet over the end of a structure, and observing the resulting droop of the extended end of the leaflet.
Claim 38
Dependent Claim 28 words
The method of claim 34 , further including testing a second leaflet and correlating the results of the droop tests and applied load tests for the two leaflets.
Claim 39
Dependent Claim 46 words
The method of claim 28 , wherein the leaflet is made of a leaflet material, and the step of applying a load comprises applying a load sufficient to stress the leaflet within a generally linear high modulus region of a stress/strain curve of the leaflet material.
Claim 40
Dependent Claim 27 words
The method of claim 28 , wherein the step of applying a load comprises applying a load sufficient to stress the leaflet between 300 and 600 kPa.
Claim 41
Dependent Claim 39 words
The method of claim 28 , wherein the location at which the load is applied comprises an idealized concentrated load point and the step of applying a load comprises applying a load to EL distributed area of the leaflet.
Claim 42
Dependent Claim 18 words
The method of claim 28 , wherein the leaflet is made of a matrix and natural tissue ingrowth.
Claim 43
Dependent Claim 22 words
The method of claim 28 , wherein the leaflet is made of a substrate on which is formed a cell growth coveting.
Claim 44
Dependent Claim 14 words
The method of claim 28 , wherein the leaflet is made of extruded collagen.

References Cited (Backward Citations)

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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) 2004-06-11 2004-12-11 2005-06-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-06-11 2008-12-11 2009-06-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-06-11 2012-12-11 2013-06-12 $7700.00 Window Closed / Lapsed

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