EP0121008A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Coating for bioprosthetic device and method of making same
Assignee: Individual
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Filing: 1983-03-29
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Granted: —
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Expires: 2003-03-29
Abstract
Abstract A coating and integral treatment for improving the biophysical stability of bioprosthetic devices after implantation, particularly with respect to calcification, and, specifically, a method for treating animal tissues, such as heart valves, to provide improved biophysical stability in allograft and heterograft transplanations. The increased stability results, in-part, from the creation of a three-dimensional matrix of a primary structural component of the prosthetic device and covalently attached calcification inhibitors. Other materials, some having additional stabilizing effects, may be utilized to form additional bridges or fill the interstitial gaps in the matrix. After implantation, the resultant modified device exhibits minimal surface for intramatrix growth of calcium phosphate crystals, and additionally, may inhibit platelet aggregation, enzymatic degradation and host rejection, while minimizing the risk of mechanical failure, in the host organism.
Inventors
- 👤 Marcel E. Nimni
- 👤 David T. Cheung
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 01:44
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/24; A61L; A61L33/00; A61L33/0005; A61L33/0011; A61F2/04; A61F2/06; A61F2/08; A61K; A61K35/00; A61K35/12; A61K35/32; A61K35/44; A61L27/00; A61L27/28; A61L27/34; A61L27/36; A61L27/3683; A61L27/3687; A61L27/50; A61L27/54; A61L2300/00; A61L2300/20; A61L2300/23; A61L2300/236; A61L2300/40; A61L2300/42; A61L2300/432; A61L2300/60; A61L2300/606; A61L2400/00; A61L2400/02
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
103 words
A process for improving the biophysical stability of bioprosthesis for hetrograft or allograft implantation, which comprises; Harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity, preferably by reacting the tissue with Glutaraldehyde; soaking the tissue in an aqueous solution of a calcification inhibitor; covalently binding the calcification inhibitor to the tissue thereby forming a three dimensional matrix, for example, by reacting the tissue with a carbodiimide, preferably 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide; and sterilizing the matrix, preferably in a solution containing formaldehyde or alcohol or a mixture thereof.
Claim 2
Dependent Claim
103 words
A process for improving the biophysical stability of bioprosthesis for hetrograft or allograft implantation, which comprises; Harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity, preferably by reacting the tissue with Glutaraldehyde; soaking the tissue in an aqueous solution of a calcification inhibitor; covalently binding the calcification inhibitor to the tissue thereby forming a three dimensional matrix, for example, by reacting the tissue with a carbodiimide, preferably 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide; and sterilizing the matrix, preferably in a solution containing formaldehyde or alcohol or a mixture thereof.
Claim 3
Dependent Claim
17 words
A process according to Claim 1, wherein the calcification inhibitor is a polyanion, preferably an anionic polysaccharide.
Claim 4
Dependent Claim
27 words
A process according to Claim 1, wherein the calcification inhibitor is a sulfated polysaccharide, preferably chondroitin-4-sulfate, chondroitin-6-sulfate, hyaluronate or a mixture of any two or more thereof.
Claim 5
Dependent Claim
55 words
A process according to any one of Claims 1 to 3, wherein the tissue is treated prior to or simultaneously with the covalent binding step to the action of a bridging agent, for example, a diamine, preferably an aliphatic diamine, that can covalently bind to the tissue thereby providing additional sites for peptide bond formation.
Claim 6
Dependent Claim
26 words
A process according to any one of Claims 1 to 4, which further includes the.step of covalently bonding an antithrombogenic agent, preferably heparin to the matrix.
Claim 7
Dependent Claim
35 words
A process according to any one of Claims 1 to 5, wherein the tissue is an animal connective tissue, preferably a mammalian heart valve, blood vessel, percardium, dura mater, ligament, tendon or other collagen-rich tissue.
Claim 8
Dependent Claim
48 words
A coating for a prosthetic device that provides increased stability for allograft or heterograft implantations, said coating comprising: a three dimensional, cross-linked matrix of an exogenous calcification inhibitor covalently bound to accessible regions of the device wherein the coating is substantially non-antigenic and has minimal calcification initiation sites.
Claim 9
Dependent Claim
48 words
A coating for a prosthetic device that provides increased stability for allograft or heterograft implantations, said coating comprising: a three dimensional, cross-linked matrix of an exogenous calcification inhibitor covalently bound to accessible regions of the device wherein the coating is substantially non-antigenic and has minimal calcification initiation sites.
Claim 10
Dependent Claim
95 words
A process for treating heart valves prior to implantation into a human comprising the steps of: harvesting a fresh heart valve from a donor organism; initiating cross-links in the valve by treating with glutaraldehyde; incubating the valve in a solution containing a diamine; reacting the valve with a water soluble carbodiimide; soaking the valve in a solution containing a sulphated polysaccharide; reacting the valve with a water soluble carbodiimide in the presence of a diamine; soaking the valve in a solution containing heparin; reacting the valve with glutaraldehyde; storing the valve in a sterilizing solution.
Claim 11
Dependent Claim
95 words
A process for treating heart valves prior to implantation into a human comprising the steps of: harvesting a fresh heart valve from a donor organism; initiating cross-links in the valve by treating with glutaraldehyde; incubating the valve in a solution containing a diamine; reacting the valve with a water soluble carbodiimide; soaking the valve in a solution containing a sulphated polysaccharide; reacting the valve with a water soluble carbodiimide in the presence of a diamine; soaking the valve in a solution containing heparin; reacting the valve with glutaraldehyde; storing the valve in a sterilizing solution.
Claim 12
Dependent Claim
108 words
A process for improving the biophysical stability of bioprotheses for heterograft or allograft implantation, which comprises: harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a diphosphonate; covalently binding the diphosphonate to the tissue thereby forming a three-dimensional matrix; and sterilizing the matrix; wherein the modified tissue produced is substantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 13
Dependent Claim
108 words
A process for improving the biophysical stability of bioprotheses for heterograft or allograft implantation, which comprises: harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a diphosphonate; covalently binding the diphosphonate to the tissue thereby forming a three-dimensional matrix; and sterilizing the matrix; wherein the modified tissue produced is substantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 14
Dependent Claim
108 words
A process for improving the biophysical stability of bioprostheses for heterograft or allograft implantation, which comprises: harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a dye; covalently binding the dye to the tissue thereby forming a three-dimensional matrix; and sterilizing the matrix; wherein the modified tissue produced is substantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 15
Dependent Claim
108 words
A process for improving the biophysical stability of bioprostheses for heterograft or allograft implantation, which comprises: harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a dye; covalently binding the dye to the tissue thereby forming a three-dimensional matrix; and sterilizing the matrix; wherein the modified tissue produced is substantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 16
Dependent Claim
107 words
A process for improving the biophysical stability of bioprostheses for heterograft or allograft implantation, which comprises: harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue-to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a phosphoprotein; covalently binding the phosphoprotein to the tissue thereby forming a three-dimensional matrix; and sterilizing the matrix; wherein the modified tissue produced is substantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 17
Dependent Claim
107 words
A process for improving the biophysical stability of bioprostheses for heterograft or allograft implantation, which comprises: harvesting tissue from an organism; initiating covalent cross-links in the protein structure of the tissue-to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a phosphoprotein; covalently binding the phosphoprotein to the tissue thereby forming a three-dimensional matrix; and sterilizing the matrix; wherein the modified tissue produced is substantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 18
Dependent Claim
112 words
A process for improving the biophysical stability of bioprostheses for heterograft or allograft implantation, which comprises: harvesting the tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a chelating agent; covalently binding the chelating agent to the tissue thereby forming a three-dimensional matrix; and, sterilizing the matrix; wherein the modified tissue produced is sub- atantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
Claim 19
Dependent Claim
112 words
A process for improving the biophysical stability of bioprostheses for heterograft or allograft implantation, which comprises: harvesting the tissue from an organism; initiating covalent cross-links in the protein structure of the tissue to protect the tissue from excessive swelling or other losses of structural integrity; soaking the tissue in an aqueous solution of a chelating agent; covalently binding the chelating agent to the tissue thereby forming a three-dimensional matrix; and, sterilizing the matrix; wherein the modified tissue produced is sub- atantially water insoluble; and, after implantation in a host organism, the matrix is less likely to elicit an antigenic response or to be subject to calcification than natural tissue or tanned tissue.
References Cited (Backward Citations)
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