Porous synthetic vascular grafts with oriented ingrowth channels

• US 7,033,388 B2
• Filed: 07/02/2002
• Issued: 04/25/2006
• Est. Priority Date: 11/23/1998
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Zilla, Peter Paul, Bezuidenhout, Deon
• Primary Examiner(s): Bui, Vy Q.
• Application Number:
  US10/187,522
• Publication Number:
  US 20020169499A1
• Time in Patent Office: 1,393 Days
• Field of Search: 623 111- 139, 623/1.44, 606/108, 606191-198
• US Class Current: 623/1.39
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61F 2250/0031 made from both resorbable and non-resorbable prosthetic parts, e.g. adjacent parts
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/507 for artificial blood vessels apparatus for applying cells on a blood vessel prosthesis A61F2/062
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/09 Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/32 with annular openings, e.g. for forming tubular articles
• CPC Class Codes: B29C 53/587 having a non-uniform wall-structure, e.g. with inserts, perforations, locally concentrated reinforcements
• CPC Class Codes: B29C 53/665 Coordinating the movements of the winding feed member and the mandrel
• CPC Class Codes: B29K 2075/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/045 with open cells
• CPC Class Codes: B29K 2105/06 containing reinforcements, fillers or inserts
• CPC Class Codes: B29K 2105/101 Oriented
• CPC Class Codes: B29L 2031/7534 Cardiovascular protheses
• CPC Class Codes: C08L 75/04 Polyurethanes

Abstract

A vascular prosthesis is constructed from a structure having interconnected, helically oriented channel-porosity to allow oriented ingrowth of connective tissue into a wall of the prosthesis. The prosthesis can have a small internal diameter of 6 mm or less. Several different methods can be used to produce the prosthesis, including a fiber winding and extraction technique, a melt extrusion technique, and a particle and fiber extraction technique using either a layered method or a continuous method. Furthermore, mechanical properties of the prosthesis are matched with mechanical properties of the host vessel, thereby overcoming problems of compliance mismatch.

Claims

1. A method of making a prosthesis comprising the steps of:

assembling a mandrel in a winding device;

coating an extractable fiber with a coating solution, wherein the coating solution comprises a graft material dissolved in a graft material solvent;

winding the extractable fiber onto the mandrel;

solidifying the coating solution; and

extracting the fiber from the graft material.

2. The method of claim 1 further comprising the step of winding a non-extractable, reinforcing fiber onto the mandrel simultaneously with the extractable fiber.

3. The method of claim 1 wherein solidifying the coating solution is accomplished by precipitating the graft material in a precipitation solvent.

4. The method of claim 1 wherein solidifying the coating solution is accomplished by drying the graft material solvent in the coating solution.

5. The method of claim 1 wherein the mandrel has a diameter about equal to an internal diameter of the vascular graft prosthesis.

6. The method of claim 1 wherein the diameter of the mandrel is in a range of 1–

20 mm.

7. The method of claim 1 wherein the diameter of the mandrel is in a range of 2–

6 mm.

8. The method of claim 1 wherein the fiber has a diameter in a range of 10–

300 μ

m.

9. The method of claim 1 wherein the fiber has a diameter in a range of 40–

110 μ

m.

10. The method of claim 1 wherein the fiber comprises a polymer.

11. The method of claim 1 wherein the graft material comprises a thermoplastic elastomer.

12. The method of claim 1 wherein the graft material comprises a polyurethane.

13. The method of claim 1 wherein the coating solution further comprises extractable beads.

14. An aortic valve prosthesis made according to the method of claim 1.

15. A vascular graft prosthesis made according to the method of claim 1.