DELIVERY SYSTEM WITH LOW LONGITUDINAL COMPRESSIBILITY

• US 20090281610A1
• Filed: 05/05/2009
• Published: 11/12/2009
• Est. Priority Date: 05/07/2008
• Status: Active Grant

• Current Assignee: Cook Medical Technologies, LLC (Cook Group Incorporated)
• Original Assignee: Cook Incorporated (Cook Group Incorporated)
• Inventors: Parker, Fred T.
• Granted Patent: US 8,992,591 B2
• Time in Patent Office: Days
• US Class Current: 623/1.110
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod

Abstract

An improved delivery system for an implantable medical device includes a retention sheath having a proximal end, a distal end, and an inner lumen extending from the proximal end to the distal end. The implantable medical device is disposed within the inner lumen of the retention sheath, which restrains the implantable medical device. A plurality of substantially incompressible rings are disposed within the inner lumen of the retention sheath in a stacked co-axial configuration that extends from the proximal end of the retention sheath in a pre-deployment position to a proximal end of the implantable medical device. Each ring in the plurality of separate rings abuts at least a portion of an adjacent ring. The plurality of separate rings is configured to prevent the implantable medical device from moving toward a proximal end of the retention sheath when the retention sheath is moved from the pre-deployment position to a deployment position.

Claims

1. A delivery system for an implantable medical device, comprising:

a retention sheath comprising a proximal end, a distal end, and an inner lumen extending from said proximal end to said distal end, wherein said retention sheath is movable in an axial direction from a pre-deployment position to a deployment position;

an implantable medical device disposed within said inner lumen of said retention sheath, said retention sheath thereby restraining said implantable medical device; and

a plurality of separate rings disposed within said inner lumen of said retention sheath in a stacked co-axial configuration, wherein each ring in said plurality of separate rings abuts at least a portion of an adjacent ring,

wherein said plurality of separate rings is substantially non-compressible in said axial direction and a longitudinal length of said plurality of separate rings in said stacked co-axial configuration does not change when said retention sheath is moved from said pre-deployment position to said deployment position.

2. The delivery system according to claim 1, wherein said implantable medical device is a self-expanding stent.

3. The delivery system according to claim 1, wherein said plurality of separate rings extends from said proximal end of said retention sheath in said pre-deployment position to a proximal end of said implantable medical device.

4. The delivery system according to claim 1, further comprising:

an inner catheter comprising an outer surface having a diameter that is less than an inner diameter of said plurality of separate rings and a distal tip having an outer diameter that is greater than said inner diameter of said plurality of separate rings, wherein said distal tip is disposed at a distal end of said inner catheter, and said inner catheter is disposed within a space defined by said inner diameter of said plurality of separate rings.

5. The delivery system according to claim 1, wherein each of said plurality of separate rings has a cross-sectional shape selected from one of the group consisting of quadrilateral, circular, and triangular.

6. The delivery system according to claim 1, wherein at least one ring in said plurality of separate rings is radiopaque.

7. The delivery system according to claim 1, wherein said plurality of separate rings is made of a metal selected from one of the group consisting of nitinol, stainless steel, and titanium.

9. The delivery system of claim 7, wherein the implantable medical device is a self-expanding stent.

10. The delivery system according to claim 1, wherein said plurality of separate rings extends from said proximal end of said retention sheath in said pre-deployment position to a proximal end of said implantable medical device.

11. The delivery system of claim 7, wherein said plurality of separate rings are stacked in a continuous co-axial configuration extending from said proximal end of said retention sheath in said pre-deployment position to said proximal end of said self-expanding stent.

12. The delivery system of claim 7, wherein said thickness of said individual rings in said plurality of separate rings increases in an axial direction toward said proximal end of said retention sheath.

13. The delivery system according to claim 7, further comprising:

an inner catheter comprising an outer surface having a diameter that is less than an inner diameter of said plurality of separate rings and a distal tip having an outer diameter that is greater than said inner diameter of said plurality of separate rings, wherein said distal tip is disposed at a distal end of said inner catheter, and said inner catheter is disposed within a space defined by said inner diameter of said plurality of separate rings.

14. The delivery system according to claim 7, wherein each of said plurality of separate rings has a cross-sectional shape selected from one of the group consisting of quadrilateral, circular, elliptical, and triangular.

15. The delivery system according to claim 7, wherein at least one ring in said plurality of separate rings is radiopaque.

16. The delivery system according to claim 7, wherein said plurality of separate rings is made from a metal selected from one of the group consisting of nitinol, stainless steel, and titanium.

8. A delivery system for an implantable medical device, comprising:

a retention sheath comprising a proximal end, a distal end, and an inner lumen extending from said proximal end to said distal end, wherein said retention sheath is movable in an axial direction from a pre-deployment position to a deployment position;

an implantable medical device disposed within said inner lumen of said retention sheath, said retention sheath thereby restraining said implantable medical device; and

a plurality of separate rings disposed within said inner lumen of said retention sheath in a stacked co-axial configuration, wherein each of said rings in said plurality of separate rings abuts at least a portion of an adjacent ring,

wherein each ring in said plurality of separate rings has a thickness in an axial direction, and said thickness varies among at least some rings in said plurality of separate rings.

17. A method of manufacturing an expandable stent delivery system, said method including:

inserting an implantable medical device into an opening at a distal end of a retention sheath, wherein said retention sheath comprises an outer diameter and an inner lumen extending therethrough, and said inner lumen forms said opening at said distal end of said retention sheath;

inserting an inner catheter into said inner lumen through said opening at said distal end of said retention sheath, said inner catheter comprising a lumen;

placing a plurality of separate rings around a mandrel;

inserting said mandrel into a proximal end of said lumen of said inner catheter; and

moving said plurality of separate rings from said mandrel into said inner lumen of said retention sheath by transferring said plurality of separate rings from said mandrel into an annular space between said inner catheter and said retention sheath.

18. The method of claim 17 wherein said mandrel is a wire.

19. The method of claim 17 further comprising inserting said inner catheter through an axial center of said implantable medical device.

20. The method of claim 17, wherein said plurality of separate rings are transferred along said outer surface of said inner catheter such that a distal most ring in said plurality of separate rings abuts a proximal end of said implantable medical device and a proximal most ring in said plurality of separate rings abuts a distal end of a control device attached to a proximal end of said retention sheath.