PLEATED DEPLOYMENT SHEATH

• US 20090182411A1
• Filed: 01/15/2008
• Published: 07/16/2009
• Est. Priority Date: 01/15/2008
• Status: Active Grant

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Inventors: Silverman, James D., Irwin, Craig W.
• Granted Patent: US 8,845,712 B2
• Time in Patent Office: Days
• US Class Current: 623/1.120
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61B 2017/3435 using everted sleeves
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61F 2/97 the outer sleeve being splittable
• CPC Class Codes: A61F 2002/9665 with additional retaining means

Abstract

A deployment sheath for medical devices is provided that includes one or more pleats in its pre-deployment state that are allowed to open during deployment so as to facilitate easier device deployment and sheath removal. Preferably, the sheath is removed by everting it over itself during the delivery process. By orienting the pleats along the length of the sheath, preferably helically around the sheath, the sheath undergoes a predictable enlargement during deployment so as to relieve friction of the everted sheath sliding along itself during deployment. This allows the sheath to be removed with less tension than previous everting sheath constructions and assures more accurate device placement in a patient.

Claims

1. A medical device delivery system comprising

a tubular sheath, having a length, mounted about and containing a medical device;

wherein said tubular sheath includes at least one pleat oriented along at least a portion of the length.

2. The medical device delivery system of claim 1 wherein the pleat is oriented helically along at least a portion of the length of the sheath.

3. The medical device delivery system of claim 1 wherein the sheath includes means to assist in defining the pleat.

4. The medical device delivery system of claim 1 wherein a portion of the pleat is reinforced.

5. The medical device delivery system of claim 4 wherein the pleat is reinforced with a reinforcing material.

6. The medical device delivery system of claim 5 wherein the reinforcing material comprises a polymer strip attached to the sheath.

7. The medical device delivery system of claim 2 wherein at least a portion of the sheath is everted over itself prior to the medical device deployment.

8. The medical device delivery system of claim 7 wherein when tension is applied to the portion of the sheath that is everted, the everted portion of the sheath slides along the length of the device and the pleat progressively opens to provide an enlarged diameter to the everted portion of the sheath.

9. The medical device delivery system of claim 1 wherein the sheath comprises expanded polytetrafluoroethylene.

10. The medical device delivery system of claim 9 wherein the sheath comprises a tube of multiple layers of expanded polytetrafluoroethylene film.

11. The medical device delivery system of claim 1 wherein the medical device is an endoprosthesis.

12. The medical device delivery system of claim 11 wherein the endoprosthesis is a self-expanding device.

13. A medical device deployment system comprising

a medical device having a length;

a sheath mounted around the medical device along at least a portion of its length,

wherein prior to deployment the sheath is at least partially everted over itself to form an interior segment and an exterior segment;

wherein at least a portion of the interior segment of the sheath includes a helically oriented pleat.

14. The medical device deployment system of claim 13 wherein deployment occurs by applying tension to the exterior segment of the sheath to evert the interior segment and progressively reorient it into the exterior segment, with the pleat progressively opening as the sheath everts.

15. The medical device deployment system of claim 14 wherein the un-pleated exterior segment is of a sufficiently greater diameter than the pleated interior segment so as to reduce frictional contact between the interior segment and the exterior segment during deployment.

16. The medical device deployment system of claim 13 wherein a portion of the pleat is reinforced with a reinforcing material.

17. The medical device deployment system of claim 16 wherein the reinforcing material comprises a polymer strip attached to the sheath.

18. The medical device deployment system of claim 13 wherein the sheath comprises expanded polytetrafluoroethylene.

19. The medical device deployment system of claim 18 wherein the sheath comprises a tube of multiple layers of expanded polytetrafluoroethylene film.

20. The medical device delivery system of claim 13 wherein the medical device is an endoprosthesis.

21. The medical device delivery system of claim 20 wherein the endoprosthesis is a self-expanding device.

22. A delivery and deployment system for an endoprosthesis, comprising:

an endoprosthesis having a distal end, a proximal end, a first, smaller compacted diameter for insertion into a body conduit and a second, larger deployed diameter, said endoprosthesis provided at the first, smaller compacted diameter; and

a constraining sheath wherein a first length portion of said sheath is fitted around the compacted endoprosthesis and extends along a length of the endoprosthesis and a second length portion that is everted back over the first length portion, wherein at least the first length portion of the constraining sheath includes a helically oriented fold.