Solution and method for treating autologous tissue for implant operation

• US 6,352,708 B1
• Filed: 10/14/1999
• Issued: 03/05/2002
• Est. Priority Date: 10/14/1999
• Status: Expired due to Term

• Current Assignee: The International Heart Institute of Montana Foundation
• Original Assignee: The International Heart Institute of Montana Foundation
• Inventors: Pang, David C., Cheung, David T., Duran, Carlos M. G.
• Primary Examiner(s): AZPURU, CARLOS A
• Application Number:
  US09/418,674
• Time in Patent Office: 873 Days
• Field of Search: 424/423, 523/113, 523/116, 514/772.3
• US Class Current: 424/423
• CPC Class Codes: A61F 2/2415 Manufacturing methods
• CPC Class Codes: A61L 2430/40 Preparation and treatment of biological tissue for implantation, e.g. decellularisation, cross-linking
• CPC Class Codes: A61L 27/3604 characterised by the human or animal origin of the biological material, e.g. hair, fascia, fish scales, silk, shellac, pericardium, pleura, renal tissue, amniotic membrane, parenchymal tissue, fetal tissue, muscle tissue, fat tissue, enamel
• CPC Class Codes: A61L 27/3687 characterised by the use of chemical agents in the treatment, e.g. specific enzymes, detergents, capping agents, crosslinkers, anticalcification agents

Abstract

An aqueous solution containing a water miscible organic solvent, polyethylene glycol and heparine, is used to modify the tissue reactivity of an autologous tissue freshly obtained from a host mammal and to render the tissue temporarily more rigid than in its native state, and better suited for shaping, molding, handling and cutting prior to implantation into the host patient. The implant is highly resistant or immune to thickening, contraction and reduced fibrin deposition after it is implanted and exposed to the bloodstream of the host.

Claims

1. An aqueous composition adapted for treating autologous biological tissue for modifying its tissue reactivity and for rendering the tissue temporarily more rigid than in its natural state, the composition comprising:

approximately 10 to 70% by volume of a water miscible non-toxic organic solvent selected from the group consisting of an alcohol having 1 to 3 carbons, acetone, acetonitrile and methyl ethyl ketone;

approximately 2 to 30% by weight of polyethylene glycol having a molecular weight in the range of approximately 6,000 to 15,000 D;

approximately 0.01 to 1.0% by weight of heparin, and

the balance of the composition substantially consisting of water.

2. The liquid composition of claim 1 wherein the water miscible organic solvent is ethyl alcohol.

3. The liquid composition of claim 2 that contains approximately 15 to 60% ethyl alcohol.

4. The liquid composition of claim 3 that contains approximately 50% ethyl alcohol.

5. The liquid composition of claim 1 that contains approximately 2 to 10% polyethylene glycol.

6. The liquid composition of claim 5 that contains approximately 5% polyethylene glycol.

7. The liquid composition of claim 5 wherein the polyethylene glycol has a molecular weight of approximately 8,000 D.

8. The liquid composition of claim 1 that contains approximately 0.1 to 0.7% heparin.

9. The liquid composition of claim 8 that contains approximately 0.5% heparin.

10. An aqueous liquid composition adapted for treating autologous biological tissue for modifying its tissue reactivity and for rendering the tissue temporarily more rigid than in its natural state, the composition comprising:

approximately 15 to 60% by volume of ethyl alcohol;

approximately 2 to 10% by weight of polyethylene glycol of a molecular weight of approximately 8,000 D;

approximately 0.1 to 0.7% by weight of heparine, and

the balance of the composition substantially consisting of water.

11. The liquid composition of claim 10 comprising approximately 50% ethyl alcohol, approximately 5% polyethylene glycol and approximately 0.5% heparine.

12. A method for modifying the tissue reactivity of an autologous tissue freshly obtained from a host mammal and for rendering the tissue temporarily more rigid than in its native state, the method comprising:

exposing said autologous tissue to an aqueous composition, comprising;

approximately 10 to 70% by volume of a water miscible non-toxic organic solvent selected from the group consisting of an alcohol having 1 to 3 carbons, acetone, acetonitrile and methyl ethyl ketone;

approximately 2 to 30% by weight of polyethylene glycol having a molecular weight in the range of approximately 6,000 to 15,000 D;

approximately 0.01 to 1.0% by weight of heparin, and

the balance of the composition substantially consisting of water.

13. The method of claim 12 where in the liquid composition the water miscible organic solvent is ethyl alcohol.

14. The method of claim 13 where the liquid composition contains approximately 15 to 60% ethyl alcohol.

15. The method of claim 13 where the liquid composition contains approximately 2 to 10% polyethylene glycol.

16. The method of claim 13 where the liquid composition contains approximately 0.1 to 0.7% heparin.

17. The method of claim 13 where the liquid composition contains approximately 50% ethyl alcohol, approximately 5% polyethylene glycol of a molecular weight of approximately 8,000 D and approximately 0.5% heparin.

18. The method of claim 12 where the autologous tissue freshly obtained from a host mammal comprises a biological membrane.

19. The method of claim 12 where the autologous tissue is selected from a group consisting of peritoneum, pericardium, pleura and tendon.

20. The method of claim 12 wherein the step of exposing the autologous tissue to the liquid composition is by immersing the tissue in the liquid composition.

21. The method of claim 20 further comprising the step of placing the autologous tissue in a mold.

22. The method of claim 21 wherein the autologous tissue is placed in the mold before the tissue is exposed to the liquid composition, and wherein the tissue is exposed to the liquid composition while it is held in said mold, thereby forming said tissue into a predetermined configuration.

23. The method of claim 22 further comprising the step of trimming excess autologous tissue by cutting while said tissue is still in the mold and after it has been exposed to said liquid composition for at least approximately 2 to 8 minutes.

24. The method of claim 23 further comprising the step of implanting the trimmed tissue into the host.

25. The method of claim 24 further comprising the step of irrigating the implanted tissue with isotonic saline solution thereby causing the physical properties of the tissue to return to their substantially native state.