Articulated Catheter

• US 20080139999A1
• Filed: 05/17/2005
• Published: 06/12/2008
• Est. Priority Date: 05/17/2004
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: C.R. Bard, Inc. (Becton, Dickinson & Co)
• Inventors: O'Boyle, Gary S., Falwell, Gary S., Gibson, Charles A.
• Granted Patent: US 8,007,462 B2
• Time in Patent Office: Days
• US Class Current: 604/95.04
• CPC Class Codes: A61M 2025/0161 wherein the distal tips have two or more deflection regions
• CPC Class Codes: A61M 25/0041 pre-formed, e.g. specially adapted to fit with the anatomy of body channels urethral catheters A61F2/04
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: A61M 25/0108 using radio-opaque or ultrasound markers
• CPC Class Codes: A61M 25/0141 having flexible regions as a result of using materials with different mechanical properties
• CPC Class Codes: A61M 25/0144 having flexible regions as a result of inner reinforcement means, e.g. struts or rods
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires

Abstract

Methods and apparatuses for manipulating an elongated flexible shaft of a catheter provide case and reliability of positioning electrodes against or near tissue. Dual-bend flexible distal tips (30) may be used in combination with flat wires. In some embodiments, flat wires which are free to rotate upon initial bending of shaft segments are employed. In some embodiments, one or more transition segments (48) are used to relocate the satellite lumen-to-main lumen transition of pull wires (42, 40) away from a change in shaft stiffness.

Claims

1. A catheter comprising:

an elongated flexible shaft including;

a flexible distal tip having a first segment that is bendable;

a second segment that is immediately proximal to the first segment and has a stiffness that is greater than the first segment;

a main shaft that is proximal to the flexible distal tip;

a pull wire main lumen; and

a first pull wire satellite lumen, the first pull wire satellite lumen extending from the first bendable segment into the second segment;

and

a first pull wire that has a distal portion anchored within the flexible distal tip, travels within the first pull wire satellite lumen and into the pull wire main lumen, and attaches to a first pull wire actuation element.

2. A catheter as in claim 1, wherein the first pull wire satellite lumen extends at least two millimeters into the second segment.

3. A catheter as in claim 1, wherein the first pull wire satellite lumen extends at least three millimeters into the second segment.

4. A catheter as in claim 1, wherein the first pull wire satellite lumen extends at least five millimeters into the second segment.

5. A catheter as in claim 4, wherein the second segment is formed of the same materials as the main shaft.

6. A catheter as in claim 1, wherein the first pull wire satellite lumen extends at least ten millimeters into the second segment.

7. A catheter as in claim 1, wherein the pull wire satellite lumen extends through the entire length of the second segment.

8. A catheter as in claim 1, wherein the second segment is separately distinguishable from the main shaft.

9. A catheter as in claim 8, wherein the second segment is less stiff than the main shaft.

10. A catheter as in claim 8, wherein the second segment is stiffer than the main shaft.

11. A catheter as in claim 1, further comprising:

a second pull wire satellite lumen that extends from the first bendable segment into the second segment; and

a second pull wire that is anchored within the flexible distal tip, travels within the second pull wire satellite lumen and into the pull wire main lumen, and attaches to a second pull wire actuation element;

wherein

actuating the second pull wire actuation element bends the first bendable segment in a direction that is different from a direction that the first bendable segment bends in response to actuation of the first pull wire actuation element.

12. A catheter as in claim 1, wherein the first bendable segment is a distal bending segment and the flexible distal tip further comprises a proximal bending segment, the first pull wire being anchored within one of the proximal bending segment and the distal bending segment, and a third pull wire being anchored within the other of the proximal bending segment and the distal bending segment, the third pull wire being attached to a third pull wire actuation element.

13. A catheter as in claim 12, wherein actuation of the first pull wire actuation element bends one of the proximal bending segment and the distal bending segment in a direction opposite to the direction that the other of the proximal bending segment and the distal bending segment bends in response to actuation of the third pull wire actuation element.

14. A catheter as in claim 13, wherein the first pull wire is anchored within the distal bending segment, the third pull wire is anchored within the proximal bending segment, and actuation of the first pull wire actuation element and the third pull wire actuation element bends the distal bending segment and the proximal bending segment within substantially the same plane.

15. A catheter as in claim 14, wherein actuation of the first pull wire actuation element bends the distal bending segment in direction opposite to the direction that the proximal bending segment bends in response to actuation of the third pull wire actuation element.

16. A catheter as in claim 14, further comprising:

a second pull wire satellite lumen;

a second pull wire that has a distal portion anchored within the distal bending segment of the flexible distal tip, travels within the second pull wire satellite lumen and into the pull wire main lumen, and attaches to a second pull wire actuation element;

a fourth pull wire satellite lumen; and

a fourth pull wire that has a distal portion anchored within the proximal bending segment of the flexible distal tip, travels within the fourth pull wire satellite lumen and into the pull wire main lumen, and attaches to a fourth pull wire actuation element;

wherein

actuation of the second pull wire actuation element bends the distal bending segment of the flexible distal tip in a direction that is different from a direction that the distal bending segment bends in response to actuation of the first pull wire actuation element; and

actuation of the fourth pull wire actuation element bends the proximal bending segment of the flexible distal tip in a direction that is different from a direction that the proximal bending segment bends in response to actuation of the third pull wire actuation element.

17. A catheter as in claim 1, further comprising a flat wire and a flat wire lumen, the flat wire extending along at least a portion of the flexible distal tip within the flat wire lumen.

18. A catheter as in claim 17, wherein the flat wire has a distal end and a proximal end, and the distal end is not secured.

19. A catheter as in claim 17, wherein the flat wire has a distal end and a proximal end, and the distal end is free to rotate upon initial bending of the flexible distal tip.

20. A catheter comprising:

an elongated flexible shaft comprising;

a pull wire lumen;

a pull wire for bending a first segment of the elongated flexible shaft, the pull wire being anchored within the elongated flexible shaft, extending through the pull wire lumen and attachable to a pull wire actuation element;

a flat wire lumen; and

a flat wire positioned within the flat wire lumen and having a longitudinal axis, a proximal end and a distal end, the flat wire being free to rotate about the longitudinal axis upon initial bending of the first segment.

21. A catheter as in claim 20, wherein the flat wire lumen and the flat wire are constructed and arranged such that upon further bending of the first segment, contact between the flat wire and the flat wire lumen prevents the flat wire from rotating.

22. A catheter as in claim 21, further comprising a second segment that is a proximal bending segment of a flexible distal tip;

wherein

the first segment is a distal segment of the flexible distal tip.

23. A catheter as in claim 22, wherein the flat wire maintains the first and second segments in substantially the same plane when at least one of the segments is bent.

24. A catheter as in claim 23, wherein the first and second segments are bendable in opposite directions.

25. A catheter as in claim 24, wherein the first and second segments are independently bendable.

26. A catheter as in claim 22, wherein the first segment is bendable in a first plane and the second segment is independently bendable in a different plane.

27. A catheter comprising:

an elongated flexible shaft comprising;

a main shaft portion;

a first pull wire disposed within the elongated flexible shaft;

a second pull wire disposed within the elongated flexible shaft;

a flexible distal tip including a proximal bending segment and a distal bending segment, the proximal bending segment being bendable by pulling the first pull wire such that the proximal bending segment bends in a first direction and within a plane, the distal bending segment being bendable by pulling the second pull wire such that the distal bending segment bends in a second direction that is opposite to the first direction and substantially within the same plane as the proximal bending segment;

a flat wire lumen; and

a flat wire extending through the flat wire lumen.

28. A catheter as in claim 27 wherein the flat wire maintains the proximal and distal bending segments in substantially the same plane when at least one of the segments is bent.

29. A catheter as in claim 27, wherein the proximal and distal bending segments are bendable in opposite directions.

30. A catheter as in claim 29, wherein the proximal and distal bending segments are independently bendable.

31. A catheter as in claim 27, further comprising:

a transition segment interposed between the distal bending segment and the proximal bending segment, the transition segment having a stiffness that is greater than the distal bending segment;

a pull wire main lumen; and

a pull wire satellite lumen for guiding the second pull wire, the pull wire satellite lumen extending from the distal bending segment into and through the transition segment;

wherein

the second pull wire is guided into the pull wire main lumen at a location that is proximal to the transition segment.