RAPID EXCHANGE ENTERAL STENT DELIVERY SYSTEM

• US 20080188804A1
• Filed: 01/30/2008
• Published: 08/07/2008
• Est. Priority Date: 02/05/2007
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Leanna, Gary J., Jordan, Gary A., Roberts, George T.
• Granted Patent: US 7,815,601 B2
• Time in Patent Office: Days
• US Class Current: 604/103.04
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61M 2025/0063 having means, e.g. stylets, mandrils, rods or wires to reinforce or adjust temporarily the stiffness, column strength or pushability of catheters which are already inserted into the human body
• CPC Class Codes: A61M 2025/018 Catheters having a lateral opening for guiding elongated means lateral to the catheter
• CPC Class Codes: A61M 2025/0183 Rapid exchange or monorail catheters
• CPC Class Codes: A61M 2210/1042 Alimentary tract A61M2210/0618 takes precedence
• CPC Class Codes: A61M 25/00 Catheters; Hollow probes dilators A61M29/00; peritoneal catheters A61M1/285; tracheal tubes A61M16/04; for drainage A61M27/00; for uterus, vagina or rectum A61M31/00 ; for measuring or testing A61B; materials for catheters A61L29/00

Abstract

Methods of and devices for palliating gastrointestinal strictures using rapid exchange type enteral stent placement catheters. The catheter may include an inner member and an outer member, with the two members being slidable with respect to one another. In various device embodiments, a ramp for directing a guidewire out from within the catheter is provided using portions of the outer member or a shaped mandrel. The inner member may take a number of forms, including a tubular distal portion, a skived or integrally attached elongate midsection, and a proximal portion. A mandrel can be used in a portion proximal of the guidewire ramp, with the mandrel taking one of several disclosed forms.

Claims

1. A rapid exchange type catheter for placement of a self-expanding stent, the catheter having proximal and distal ends, the catheter comprising:

an outer member having a proximal end and a distal end and including a distal restraining portion and a guidewire port proximal of the distal restraining portion and distal of the proximal end;

an inner member having a proximal end, a distal end and including a distal stent portion for receiving a self expanding stent; and

a mandrel having a proximal end and a distal end;

wherein;

the inner member is slidable with respect to the outer member such that, when the catheter is in a first configuration, the distal restraining portion is disposed about the distal stent portion and, when the catheter is in a second configuration, the distal restraining portion is not disposed about the distal stent portion; and

when the catheter is in the first configuration, the distal end of the mandrel extends to a location near the guidewire port, and when the catheter is in the second configuration, the mandrel extends to substantially the same location.

2. The catheter of claim 1, wherein the inner member includes a guidewire lumen extending from a location proximal of the distal stent portion to the distal end of the inner member, wherein the guidewire port comprises a ramp extending down into the guidewire lumen.

3. A method of palliating a gastrointestinal stricture comprising:

providing a catheter having a proximal end, a distal end, an inner member and an outer member slidable with respect to the inner member, the inner member having a channel extending near the distal end of the outer member, the channel sized to receive a guidewire, the outer member having a ramp which extends into the channel, the catheter further having a self-expanding stent placed between the inner member and the outer member distal of the ramp;

advancing the catheter over a guidewire such that the guidewire extends within the catheter from the ramp to a location near the distal end of the catheter advancing the guidewire past the gastrointestinal stricture;

advancing the catheter over the guidewire until the stent is at a desired location with respect to the stricture;

causing the inner member and outer member to move with respect to one another such that the self-expanding stent is no longer between the outer member and the inner member;

allowing the self-expanding stent to expand.

4. The method of claim 3, wherein the outside of the distal end of the outer member has a size greater than or equal to 5 French.

5. The method of claim 3, wherein the stricture is located within the gastro-intestinal tract of a patient.

6. The method of claim 3, wherein the step of advancing the guidewire past the gastrointestinal stricture includes advancing the guidewire through a patient'"'"'s stomach and duodenum and into the small intestine of the patient.

7. A rapid exchange type catheter adapted for placing a self-expanding stent, the catheter comprising:

an outer member having a proximal portion, a distal portion, and a guidewire port therebetween, the distal portion adapted to cover a self-expanding stent;

an inner member having a proximal portion and a distal portion, the distal portion including a guidewire channel for passing a guidewire, the distal portion adapted to receive a self-expanding stent thereon;

a mandrel member having a ramp at its distal end.

8. The catheter of claim 7, wherein the mandrel is disposed within the outer member such that the ramp is located near the guidewire port of the outer member.

9. The catheter of claim 7, wherein the inner member, outer member, and mandrel are shaped and sized such that the mandrel and the inner member extend within the outer member.

10. The catheter of claim 9, wherein the mandrel fits within the inner member for a proximal portion of the length of the inner member.

11. The catheter of claim 9, wherein the mandrel does not fit within the proximal portion of the inner member.

12. The catheter of claim 9, wherein the mandrel and the proximal portion of the inner member lie within the outer member in a generally side-by-side fashion.

13. The catheter of claim 7, wherein the outer member is movable with respect to the inner member.

14. The catheter of claim 13, wherein the outer member and the mandrel remain in generally the same configuration with respect to one another when the inner member is moved with respect to the outer member.

15. The catheter of claim 13, wherein the outer member and the mandrel are coupled together to prevent relative axial movement of the outer member and the mandrel.

16. The catheter of claim 13, wherein the outer member and the mandrel are coupled to a common element such that axial movement between the outer member and the mandrel is prevented.

17. The catheter of claim 7, further comprising a first proximal apparatus and a second proximal apparatus, the first proximal apparatus attached to the proximal end of the outer member and the proximal end of the mandrel, the second proximal apparatus attached to the proximal end of the inner member.

18. A rapid exchange type stent delivery catheter comprising:

an outer tubular member having a proximal end, a distal end, and a guidewire entry port disposed closer the distal end than the proximal end;

an inner tubular member extending distally from a location distal of the guidewire entry port; and

an elongate pushing member attached to the inner tubular member and extending proximally from a location distal of the guidewire entry port to a location proximal of proximal end of the outer tubular member;

wherein the inner tubular member is axially movable with respect to the outer tubular member.

19. The catheter of claim 18, wherein the inner tubular member is axially movable to an extent such that, when a stent is disposed on the inner tubular member:

with the inner tubular member in a first position, the stent is restrained by the outer tubular member; and

with the inner tubular member in a second position, the stent is not restrained by the outer tubular member.

20. The catheter of claim 18, wherein the elongate pushing member is non-tubular.

21. The catheter of claim 18, further comprising a mandrel disposed within the outer tubular member and extending from a location near the proximal end of the outer tubular member to a location proximal of the guidewire port.

22. The catheter of claim 21, wherein the mandrel and the elongate pushing member lie in a side-by-side configuration for the majority of the length of the catheter.

23. The catheter of claim 18, wherein the outer tubular member comprises a proximal section including a hypotube having an outer diameter and a distal section comprising a distal tubular member having an outer diameter that is larger than the outer diameter of the hypotube.

24. The catheter of claim 23, wherein the distal tubular member is deformed and attached to the hypotube.

25. The catheter of claim 18, wherein the elongate pushing member includes a hypotube having a first profile at a location proximal of the guidewire port, and wherein the hypotube is collapsed to a reduced profile along a length that crosses the guidewire port.

26. The catheter of claim 18, wherein the inner tubular member defines an interior and an exterior, and the elongate pushing member is attached to the interior of the inner tubular member.

27. The catheter of claim 18, wherein the inner tubular member defines an interior and an exterior, and the elongate pushing member is attached to the exterior of the inner tubular member.

28. A rapid exchange type stent deliver catheter comprising:

an outer tubular member having a proximal end, a distal end, and a guidewire port disposed closer the distal end than the proximal end;

an inner member extending to the distal end of the catheter having a tubular distal portion extending distally from a location distal of the guidewire port and adapted to receive a guidewire; and

a tubular reinforcing member extending from a location proximal of the guidewire port to a location distal of the guidewire port and adapted to slidingly receive a portion of the inner member;

wherein the outer tubular member is attached to the tubular reinforcing member to form a ramp at the guidewire port.

29. A rapid exchange self expanding stent delivery catheter comprising:

an inner member having proximal and distal ends;

an outer member having proximal and distal ends, the outer member generally disposed about the inner member;

a mandrel, the mandrel generally disposed inside the inner member; and

a ramp for directing a guidewire from outside the outer member to inside the inner member;

wherein the ramp is secured to the mandrel and the outer member.

30. The catheter of claim 29, wherein the inner member includes a skived portion extending for an axial portion thereof, and the ramp is disposed with respect to the inner member at a location corresponding to the skived portion.

31. The catheter of claim 30, wherein the mandrel is attached to the ramp such that the mandrel extends proximally therefrom.