Occlusion device with non-thrombogenic properties

• US 6,656,206 B2
• Filed: 01/23/2002
• Issued: 12/02/2003
• Est. Priority Date: 05/13/1999
• Status: Expired due to Fees

• Current Assignee: Cardia, Inc.
• Original Assignee: Cardia, Inc.
• Inventors: Marino, Joseph A., Corcoran, Michael P., Buonomo, Peter M.
• Primary Examiner(s): Philogene, Pedro
• Application Number:
  US10/055,460
• Publication Number:
  US 20020068950A1
• Time in Patent Office: 678 Days
• Field of Search: 606/153, 606/157, 606/152, 606/154, 606/155, 606/213, 606/215, 623/2.42
• US Class Current: 606/213
• CPC Class Codes: A61B 17/0057 Implements for plugging an opening in the wall of a hollow or tubular organ, e.g. for sealing a vessel puncture or closing a cardiac septal defect sutures A61B17/04; closing rectum or urethra near body surface A61F2/0009
• CPC Class Codes: A61B 17/12122 within the heart for closing a cardiac septal defect A61B17/0057
• CPC Class Codes: A61B 17/12172 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61B 2017/00575 for closure at remote site, e.g. closing atrial septum defects
• CPC Class Codes: A61B 2017/00592 Elastic or resilient implements
• CPC Class Codes: A61B 2017/00606 Implements H-shaped in cross-section, i.e. with occluders on both sides of the opening
• CPC Class Codes: A61B 2017/1205 Introduction devices
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices artificial blood vessels A61L27/507
• CPC Class Codes: A61L 31/129 containing macromolecular fillers
• CPC Class Codes: A61L 31/146 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 33/0029 using an intermediate layer of polymer
• CPC Class Codes: A61L 33/007 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 33/064 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L33/062 takes precedence
• CPC Class Codes: C08L 29/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids

Abstract

A method of forming a PVA foam structure for use in an occlusion device such that the PVA foam structure comprises non-thrombogenic properties. The method comprises forming a PVA gel and incorporating heparin into the PVA gel. The PVA foam structure is then treated with the PVA gel and heparin mixture, such as by soaking the PVA foam structure in the gel.

Claims

1. A method of creating a non-thrombogenic polyvinyl alcohol foam structure for use in an occlusion device, the method comprising:

forming a structure from polyvinyl alcohol foam;

applying a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol to the polyvinyl alcohol foam structure; and

attaching the foam structure to an occlusion device.

2. The method of claim 1 wherein forming a structure from polyvinyl alcohol foam comprises cutting the polyvinyl alcohol foam to obtain a polyvinyl alcohol foam sheet.

3. The method of claim 1 wherein the mixture of polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol comprises a gel.

4. The method of claim 3 and further comprising rinsing the polyvinyl alcohol foam structure after the structure has been soaked in the gel.

5. The method of claim 3 wherein applying the gel to the polyvinyl alcohol foam structure comprises soaking the foam structure in the gel for about five minutes.

6. A method of forming a polyvinyl alcohol foam structure having non-thrombogenic properties for use in an occlusion device, the method comprising:

creating a polyvinyl alcohol mixture comprising polyvinyl alcohol and heparin bonded to the polyvinyl alcohol;

applying the polyvinyl alcohol heparin mixture to the polyvinyl alcohol foam structure; and

attaching the polyvinyl alcohol foam structure to an occlusion device.

7. The method of claim 6 wherein creating a polyvinyl alcohol mixture comprising polyvinyl alcohol and heparin bonded to the polyvinyl alcohol comprises:

creating a polyvinyl alcohol gel; and

adding heparin to the polyvinyl alcohol gel.

8. The method of claim 7 wherein adding the heparin to the polyvinyl alcohol gel further comprising utilizing a catalyst to assist the heparin in bonding to the polyvinyl alcohol.

9. The method of claim 7 and further comprising applying heat to the polyvinyl alcohol gel to assist the heparin in bonding to the polyvinyl alcohol.

10. The method of claim 7 and further comprising obtaining a foam structure from a larger amount of polyvinyl alcohol foam.

11. The method of claim 10 wherein obtaining a foam structure comprises obtaining a sheet of polyvinyl alcohol foam from a block of polyvinyl alcohol foam.

12. The method of claim 11 wherein applying the polyvinyl alcohol gel to the polyvinyl alcohol foam structure comprises soaking the polyvinyl alcohol foam sheet in the polyvinyl alcohol gel.

13. The method of claim 12 wherein the polyvinyl alcohol foam sheet is soaked in the polyvinyl alcohol gel for about five minutes.

14. The method of claim 13 and further comprising rinsing the polyvinyl alcohol foam sheet after applying the polyvinyl alcohol gel to the foam sheet.

15. The method of claim 14 wherein rinsing the polyvinyl alcohol foam sheet comprises rinsing the foam sheet with buffered saline and allowing the sheet to dry.

16. An occlusion device comprising a polyvinyl alcohol foam structure having non-thrombogenic properties, the polyvinyl alcohol foam structure comprising:

a polyvinyl alcohol foam substrate;

a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol applied to the polyvinyl alcohol foam substrate.

17. The polyvinyl alcohol foam structure of claim 16 wherein the mixture comprises a polyvinyl alcohol heparin gel.

18. An occlusion device, the device comprising:

a center section extending in an axial direction;

upper and lower elastic shape memory fixation devices emanating from the center section; and

first and second foam sheets attached to the upper and lower fixation devices, respectively, wherein the foam sheets are formed of polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

19. An occlusion device for the closure of a physical anomaly, the device comprising:

a support structure including a center section and first and second flexible arms extending outward from the center section; and

a first foam sheet attached to the first flexible arm, wherein the first foam sheet is formed of polyvinyl alcohol foam which has been treated with a polyvinyl alcohol gel comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

20. The occlusion device in claim 19 and further comprising a second foam sheet attached to the second flexible arm, wherein the second foam sheet is formed of polyvinyl alcohol foam which has been treated with a polyvinyl alcohol gel comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

21. An occlusion device, the device comprising:

a center strut;

a first plurality of fixation devices extending from a first end of the center strut;

a first sheet attached to the first plurality of fixation devices, wherein the first sheet is formed of polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol; and

a second plurality of fixation devices extending from a second end of the center strut.

22. The occlusion device of claim 21 and further comprising a second sheet attached to the second plurality of fixation devices, wherein the second sheet is formed of polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

23. An occlusion device, the device comprising:

a center strut having distal and proximal ends;

a first set of stranded wire support arms extending from the distal end of the center strut;

a first sheet attached to the first set of arms, wherein the first sheet is formed from polyvinyl alcohol foam which has been treated with a polyvinyl alcohol gel comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol;

a second set of stranded wire support arms extending from the proximal end of the center strut; and

a second sheet attached to the second set of support arms, wherein the second sheet is formed from polyvinyl alcohol foam which has been treated with a polyvinyl alcohol gel comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

24. An occlusion device for the closure of a physical anomaly, the occlusion device comprising:

a center piece extending in an axial direction;

first and second collapsible support frames spaced from one another and emanating from the center piece, the support frames being formed by multiwire strands; and

first and second foam sheets attached to the first and second collapsible support frames, respectively, wherein the sheets are formed from polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

25. An occlusion device, the device comprising:

a first collapsible support frame;

a second collapsible support frame, the second collapsible support frame being spaced from and connected to the first collapsible support frame;

a first sheet attached to the first collapsible support frame, wherein the first sheet is formed from polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol; and

a second polyvinyl alcohol sheet attached to the second collapsible support frame, wherein the second sheet is formed from polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

26. An occlusion device, the device comprising:

a support structure; and

a polyvinyl alcohol foam occlusion member attached to the support structure wherein the occlusion member is formed from polyvinyl alcohol foam which has been treated with a mixture comprising polyvinyl alcohol and heparin chemically bonded to the polyvinyl alcohol.

27. A method of creating foam sheets for use in an occlusion device wherein the foam sheets have non-thrombogenic properties, the method comprising:

providing polyvinyl alcohol foam;

slicing the foam into sheets of a desired size;

dipping the foam sheets into a solution comprising a thrombosis inhibitor; and

attaching the foam sheets to an occlusion device.

28. The method of claim 27 wherein the thrombosis inhibitor is heparin.

29. The method of claim 27 wherein the solution comprises a chemical fixative to aid in keeping the heparin on the foam sheets.

30. The method of claim 27 and further comprising preparing a surface of the foam sheets to accept the heparin.

31. The method of claim 30 wherein preparing the surface of the foam sheets comprises plasma etching the surfaces of the foam sheets.

32. A method of creating foam with non-thrombogenic properties for use in an occlusion device, the method comprising:

forming a mixture of polyvinyl alcohol and heparin in a liquid state;

forming a foam of the polyvinyl alcohol and heparin mixture; and

attaching the foam to an occlusion device.

33. The method of claim 32 and further comprising slicing the foam into sheets 18.