Tissue-removing catheter with adjustment mechanism

• US 10,456,161 B2
• Filed: 04/14/2016
• Issued: 10/29/2019
• Est. Priority Date: 04/14/2016
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Steele, Bradley
• Primary Examiner(s): Ulsh, George J
• Application Number:
  US15/099,331
• Publication Number:
  US 20170296222A1
• Time in Patent Office: 1,293 Days
• CPC Class Codes: A61B 17/320725 with radially expandable cutting or abrading elements A61B17/32075 takes precedence
• CPC Class Codes: A61B 17/320758 with a rotating cutting instrument, e.g. motor driven A61B17/320725, A61B17/32075 and A61B17/320783 take precedence; for removing intra-ocular material A61F9/00763; endoscopic rotatable cutting instruments A61B17/32002
• CPC Class Codes: A61B 17/320783 through side-hole, e.g. sliding or rotating cutter inside catheter
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/00327 with actuating members moving in opposite directions
• CPC Class Codes: A61B 2017/320791 with cutter extending outside the cutting window

Abstract

A tissue removing catheter includes an apposition mechanism that selectively imparts an axially compressive load on the catheter body to bend the catheter and urge a tissue-removing element toward a blood vessel wall. The apposition mechanism can include one or more adjustment lines and an adjustment mechanism for selectively tensioning one of the adjustment lines to impart the compressive load on the catheter body. Two adjustment lines can have diametrically opposed positions and be wound onto a spool of the adjustment mechanism in opposite directions so that rotation of the spool simultaneously shortens one adjustment line and lengthens the other. The catheter body can have a more flexible bending segment adjacent the tissue-removing element to promote bending near the tissue-removing element operative to urge the tissue-removing element in apposition with the blood vessel.

Claims

1. A tissue-removing catheter comprising:

an elongate catheter body configured for insertion into a body lumen of a subject, the catheter body having a proximal end portion, an opposite distal end portion, and a longitudinal axis extending between the distal and proximal end portions;

a tissue-removing element located adjacent the distal end portion of the catheter body configured to remove tissue from the body lumen;

first and second adjustment lines extending along the catheter body at circumferentially spaced apart locations about the longitudinal axis, the first and second adjustment lines having distal end portions attached to the catheter body at respective first and second connection points adjacent the distal end portion of the catheter body, and the first and second adjustment lines having opposite proximal end portions; and

an adjustment mechanism operatively connected to the proximal end portions of the first and second adjustment lines, wherein the adjustment mechanism is selectively operable to decrease an effective length of the first adjustment line extending between the first connection point and the adjustment mechanism to bend the distal end portion of the catheter body in a first direction and urge the tissue-removing element in the first direction, wherein the adjustment mechanism is selectively operable to decrease an effective length of the second adjustment line extending between the second connection point and the adjustment mechanism to bend the distal end portion of the catheter body in a second direction different than the first direction and urge the tissue-removing element in the second direction;

wherein the distal end portion includes a bending longitudinal portion and a proximally-adjacent longitudinal portion that is immediately proximal to the bending longitudinal portion;

wherein the catheter body includes a drive shaft extending along the longitudinal axis and a jacket extending circumferentially around the drive shaft;

wherein the catheter body further includes a support coil received in the jacket and extending circumferentially around the drive shaft; and

wherein the support coil is stiffer along the proximally-adjacent longitudinal portion than along the bending longitudinal portion such that the bending longitudinal portion of the catheter body has a bending stiffness that is less than a bending stiffness of the proximally-adjacent longitudinal portion of the catheter body.

2. A tissue-removing catheter as set forth in claim 1, wherein the adjustment mechanism is operable to increase said effective length of the first adjustment line when decreasing said effective length of the second adjustment line, wherein the adjustment mechanism is operable to increase said effective length of the second adjustment line when decreasing said effective length of the first adjustment line.

3. A tissue-removing catheter as set forth in claim 2, wherein the adjustment mechanism is configured to simultaneously adjust said effective lengths of the first and second adjustment lines.

4. A tissue-removing catheter as set forth in claim 3, wherein the adjustment mechanism is configured to simultaneously adjust said effective lengths of the first and second adjustment lines by the same amount.

5. A tissue-removing catheter as set forth in claim 1, wherein the adjustment mechanism comprises a spool having an axis of rotation oriented transverse to the longitudinal axis of the catheter body.

6. A tissue-removing catheter as set forth in claim 5, wherein the proximal end portions of the first and second adjustment lines are operatively attached to the spool.

7. A tissue-removing catheter as set forth in claim 6, wherein the spool is configured to be selectively rotated about the axis of rotation in a first rotational direction to simultaneously decrease said effective length of the first adjustment line and increase said effective length of the second adjustment line.

8. A tissue-removing catheter as set forth in claim 7, wherein the spool is further configured to be selectively rotated about the axis of rotation in a second rotational direction, opposite the first rotational direction, to simultaneously increase said effective length of the first adjustment line and decrease said effective length of the second adjustment line.

9. A tissue-removing catheter as set forth in claim 1, wherein the first and second adjustment lines are disposed diametrically opposite one another relative to the longitudinal axis.

10. A tissue-removing catheter as set forth in claim 1, wherein the first and second adjustment lines comprise respective first and second wires.

11. A tissue-removing catheter as set forth in claim 10, wherein the first and second wires are generally non-elastic.

12. A tissue-removing catheter as set forth in claim 1, wherein the adjustment mechanism is operable to configure the distal end portion of the catheter body from a straight configuration to a bent configuration, and from the bent configuration to the straight configuration.

13. A tissue-removing catheter as set forth in claim 12, wherein the effective lengths of the first and second adjustment lines are generally equal when the distal end portion of the catheter body is in the straight configuration.

14. A tissue-removing catheter as set forth in claim 12, wherein the adjustment mechanism and the first and second adjustment lines are configured to resist bending of the distal end portion of the catheter body when the distal end portion is in the straight configuration.

15. A tissue-removing catheter as set forth in claim 1, wherein the first and second connection points are proximal the tissue-removing element.

16. A tissue-removing catheter as set forth in claim 15, wherein the catheter body includes a rigid collar located at the first and second connection points, the distal end portions of the first and second adjustment lines being fastened to the rigid collar.

17. A tissue-removing catheter as set forth in claim 1, wherein the jacket has a first shore hardness at the bending longitudinal portion and a second shore hardness at the proximally-adjacent longitudinal portion, the first shore hardness being less than the second shore hardness.

18. A tissue-removing catheter as set forth in claim 1, wherein the catheter body further includes a braided reinforcement received in the jacket and extending circumferentially around the drive shaft.

19. A tissue-removing catheter as set forth in claim 18, wherein the braided reinforcement has a first pick rate at the bending longitudinal portion and a second pick rate at the proximally-adjacent longitudinal portion, the first pick rate being less than the second pick rate.

20. A tissue-removing catheter as set forth in claim 1, wherein the support coil has a first radial thickness at the bending longitudinal portion and a second radial thickness at the proximally-adjacent longitudinal portion, the first radial thickness being smaller than the second radial thickness.

21. A tissue-removing catheter as set forth in claim 1, further comprising a sleeve received in the jacket in radially spaced apart relationship with the longitudinal axis of the catheter body, one of the first and second adjustment lines being received in the sleeve for movement relative to the catheter body along the longitudinal axis.

22. A tissue-removing catheter comprising:

an elongate catheter body configured for insertion into a body lumen of a subject, the catheter body having a proximal end portion, an opposite distal end portion, and a longitudinal axis extending between the distal and proximal end portions;

a tissue-removing element located adjacent the distal end portion of the catheter body configured to remove tissue from the body lumen;

first and second adjustment lines extending along the catheter body at circumferentially spaced apart locations about the longitudinal axis, the first and second adjustment lines having distal end portions attached to the catheter body at respective first and second connection points adjacent the distal end portion of the catheter body, and the first and second adjustment lines having opposite proximal end portions; and

an adjustment mechanism operatively connected to the proximal end portions of the first and second adjustment lines, wherein the adjustment mechanism is selectively operable to decrease an effective length of the first adjustment line extending between the first connection point and the adjustment mechanism to bend the distal end portion of the catheter body in a first direction and urge the tissue-removing element in the first direction, wherein the adjustment mechanism is selectively operable to decrease an effective length of the second adjustment line extending between the second connection point and the adjustment mechanism to bend the distal end portion of the catheter body in a second direction different than the first direction and urge the tissue-removing element in the second direction;

wherein the distal end portion includes a bending longitudinal portion and a proximally-adjacent longitudinal portion that is immediately proximal to the bending longitudinal portion;

wherein the catheter body includes a drive shaft extending along the longitudinal axis and a jacket extending circumferentially around the drive shaft;

wherein the catheter body further includes a braided reinforcement received in the jacket and extending circumferentially around the drive shaft; and

wherein the braided reinforcement is stiffer along the proximally-adjacent longitudinal portion than along the bending longitudinal portion such that the bending longitudinal portion of the catheter body has a bending stiffness that is less than a bending stiffness of the proximally-adjacent longitudinal portion of the catheter body.