Implant delivery device

• US 20020183826A1
• Filed: 05/09/2002
• Published: 12/05/2002
• Est. Priority Date: 11/13/2000
• Status: Active Grant

• Current Assignee: Angiomed GmbH and Co Medizentechnik KG (Becton, Dickinson & Co)
• Original Assignee: Angiomed GmbH & Co.
• Inventors: Feeser, Jorg, Dorn, Jurgen
• Granted Patent: US 7,758,624 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/041 Bile ducts
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

Disclosed is a system for delivering self-expanding stents to stenting sites within the body, which minimizes trauma to the affected tissue of the patient yet, at the same time, offers the medical practitioner a robust and simple system for stent placement. These technical effects are achieved by providing a catheter which receives the stent at its proximal end and guides it to the stenting site. The catheter serves as a guide catheter and has a tapered distal tip from which the stent emerges at the site of stenting. A stent pusher can be used which abuts the proximal end of the stent inside the guide catheter. The tapered tip can be molded and can be integral with the catheter shaft or bonded to it. The guide catheter can include a figurated portion towards its distal tip. The system has particular application to stenting the carotid artery.

Claims

1. A percutaneous, transluminal stent delivery system (50) which comprises a tube (54) having a tube wall with a distal end at the distal end of the system, a proximal end within a proximal zone of the system, a luminal surface and an abluminal surface, the tube defining

i) a lumen which extends the full length of the tube, and

ii) a distal tip zone which is contiguous with the distal end of the tube, in which tip zone both the luminal (70) surface and the abluminal (72) surface taper radially inwardly with increasing nearness to the distal end (74) of the tube, at least when the distal tip zone is at 37°

C. and free from externally imposed hoop stresses; and

characterized by

a device (118) for loading a self-expanding stent into the proximal end of the tube; and

a device (56) to advance the self-expanding stent constrained from radially-outward expansion by the tube wall all the way from the proximal end of the tube to a distal end zone of the tube.

2. A delivery system as claimed in claim 1, the system further comprising a self-expanding stent (52, 120) within the tube.

3. Catheter as claimed in claim 1 or 2 wherein the tip zone is molded.

4. Catheter as claimed in claim 1, 2 or 3 wherein the tip zone is formed from the tube itself.

5. Catheter as claimed in claim 1, 2 or 3 wherein the tip zone is formed separate from the tube, and then bonded to said tube.

6. Catheter as claimed in claim 5 wherein the tip zone is welded to the tube.

7. Catheter as claimed in any one of the preceding claims wherein the tube wall thickness remains substantially constant through the length of the tip zone.

8. Catheter as claimed in any one of claims 1 to 6 wherein the tube wall thickness in the tip zone reduces with increasing nearness to said distal end.

9. Catheter as claimed in any one of the preceding claims, in which the tube wall in the distal tip zone contains one or more stretch zones which reduce the work needed to be done to expand he diameter defined by the luminal surface of the distal tip zone, throughout the length of the tip zone of the diameter defined by said luminal surface at the proximal end of the tip zone.

10. Catheter as claimed in claim 9 wherein the stretch zone is a line of weakness (238) in the tube wall which extends in a direction which has a component in the axial direction of the tube.

11. Catheter as claimed in claim 10 wherein the line of weakness is a groove (238).

12. Catheter as claimed in claim 10 wherein the line of weakness is a slit (236).

13. Catheter as claimed in any one of the preceding claims, in which the distal end is closed by a rupturable membrane (266).

14. Catheter as claimed in any one of the preceding claims, which includes a length portion of the tube, closer to the distal than to the proximal end of the tube, which is figurated.

15. Catheter as claimed in any one of the preceding claims, in which the tube wall, proximal of the distal tip zone, contains within its thickness a reinforcement element (254) which enhances pushability of the tube.

17. Catheter as claimed in any one of the preceding claims, wherein the luminal surface of the distal tip zone is substantially frusto-conical.

18. Catheter as claimed in any one of the preceding claims, wherein the abluminal surface is outwardly convex when viewed in sections parallel to the longitudinal axis of the tube.

19. Catheter as claimed in any one of the preceding claims, in combination with a guide wire (12).

20. Catheter as claimed in claim 19, wherein the guide wire has an outside diameter which is smaller than the diameter of the tube at its distal end by an amount less the 100 μ

m.

21. Catheter as claimed in any one of the preceding claims, in combination with an elongate stent pusher (64) to be accommodated within the lumen of the tube, the pusher and catheter constituting a stent delivery system which releases the stent from the distal end of the tube by withdrawing the tube proximally, relative to said pusher.

22. Catheter as claimed in claim 21, in which the stent pusher has a shaft section with a shaft diameter and a distal element which defines a pushing shoulder (60), the shoulder diameter being at least as large as the shaft diameter whereby the shoulder may bear on a proximal end surface of the stent.

23. Catheter as claimed in claim 21, in which the diameter of the stent pushing shoulder is greater than the shaft diameter.

24. Catheter as claimed in claim 22 or 23 wherein the stent pushing shoulder defines the distal-most surface of the stent pusher.

25. Catheter as claimed in claim 22, 23 or 24, wherein the distal element defines a guide wire lumen.

26. Catheter as claimed in claim 25 wherein the shaft section of the stent pusher lacks a guide wire lumen, and has a diameter sufficiently smaller than that of the catheter lumen as to enable a guide wire to lie within the catheter lumen side-by-side with the said shaft section.

27. Catheter as claimed in any one of claims 21 to 26, wherein the stent advancing device serves also as the stent pusher.

28. Catheter as claimed in any one of the preceding claims, wherein the distal tip of the catheter is visible radioscopically.

29. Catheter as claimed in claim 28, wherein the distal tip of the catheter carries a radioscopic marker band.

30. Catheter as claimed in any one of the preceding claims, in combination with means for introducing into the proximal end of the lumen of the tube a fluid useful in a medical procedure conducted at the distal tip of the tube.

31. Catheter as claimed in any one of the preceding claims, in combination with a surgical aspirator to be put into fluid communication with the proximal end of the lumen of the tube.

32. Catheter as claimed in any one of the preceding claims, wherein the loading device is adapted to keep the temperature of the stent, just prior to loading, below ambient temperature.

16. Catheter as claimed in claim 154, wherein the reinforcement element is a braided annular element (254).