Device on lead to prevent perforation and/or fixate lead

• US 20070050003A1
• Filed: 08/30/2005
• Published: 03/01/2007
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhang, Yongxing, Bodner, Jeffrey, Zarembo, Paul, Finlay, Matthew
• Granted Patent: US 8,239,039 B2
• Time in Patent Office: Days
• US Class Current: 607/116
• CPC Class Codes: A61N 1/057 Anchoring means; Means for fixing the head inside the heart
• CPC Class Codes: A61N 2001/0578 having means for removal or extraction
• CPC Class Codes: A61N 2001/0585 Coronary sinus electrodes

Abstract

This document discusses, among other things, a lead body extending longitudinally along a lead axis, a driver axially displaceable relative to the lead body, and a driven member coupled to the lead body and displaceable away from the lead axis. The driven member at least partially defines an expandable passage having at least one internal dimension. The driver is displaceable into the expandable passage and has at least one outer dimension that is larger than the at least one internal dimension of the expandable passage. An example method includes disposing a first member having a first cross-section in a lead assembly having a lead axis, an expandable passage, and a displaceable member proximate the expandable passage. The method further includes urging the first member into the expandable passage in the lead assembly, and urging the displaceable member away from the lead axis to expand the expandable passage.

Claims

1. A lead assembly comprising:

a lead body extending longitudinally along a lead axis;

a driver axially displaceable relative to the lead body; and

a driven member coupled to the lead body and displaceable away from the lead axis, the driven member at least partially defining an expandable passage, the driver displaceable into the expandable passage and having at least one outer dimension that is larger than at least one internal dimension of the expandable passage.

2. The lead assembly of claim 1, wherein the driven member is located at a distal end of the lead assembly.

3. The lead assembly of claim 2, further comprising a fixation helix connected to the driver and engageable into a tissue surface of a body.

4. The lead assembly of claim 3, wherein the driver includes a blunt surface proximate the fixation helix, at least a portion of the blunt surface on the driver contactable against the tissue surface.

5. The lead assembly of claim 4, wherein the driven member includes a blunt surface proximate the distal end of the lead assembly, at least portion of the blunt surface contactable against the tissue surface.

6. The lead assembly of claim 1, wherein the driven member has a driver engagement surface inclined toward the lead axis and contactable against a surface on the driver.

7. The lead assembly of claim 6, comprising a bendable wall portion coupled to the driven member.

8. The lead assembly of claim 6, wherein the driven member includes an inwardly-extending protrusion including the driver engagement surface, the protrusion sealing the expandable passage.

9. The lead assembly of claim 1, wherein the lead assembly includes a vessel wall engagement surface engageable against an inner wall of a blood vessel, the vessel wall engagement surface outwardly displaceable by the driver.

10. The lead assembly of claim 9, wherein the lead body includes a cavity, the driver disposed in the cavity, the driven member integral with the lead body proximate the cavity and including the vessel wall engagement surface.

11. The lead assembly of claim 9, wherein the lead assembly further comprises at least one tooth engageable against an inner wall of a blood vessel.

12. The lead assembly of claim 11, wherein the lead body includes a compressible material proximate the tooth, the tooth disposed in the compressible material and at least partially retracted into the lead body when the compressible material is not compressed, and the tooth at least partially extended from the lead body when the compressible material is compressed.

13. The lead assembly of claim 1, further comprising helical internal threads coupled to the lead body, the driver including a helical member engageable on the threads and a pusher displaceable into the expandable passage.

14. The lead assembly of claim 1, further comprising threads coupled to the lead body, the driver rotateable and axially displaceable on the threads.

15. The lead assembly of claim 1, wherein the driver includes a structure engageable with a portion of the driven member, the driver fixateable in a particular position with respect to the driven member by engagement of the structure with the portion of the driven member.

16. The lead assembly of claim 1, comprising a plurality of driven members contactable by the driver and displaceable by away from the lead axis, each of the plurality of driven members including an engagement surface inclined toward the lead axis and slidable against the driver.

17. The lead assembly of claim 1, further comprising a conductor extending through a lumen in the lead body and an electrode electrically coupled to the conductor and situated proximate the driven member.

18. A lead assembly comprising:

a lead body extending longitudinally along a lead axis, the lead body having a proximal end and a distal end;

a fixation structure proximate the distal end of the lead body;

a displaceable member coupled to the lead body and displaceable away from the lead axis, the displaceable member having an outer surface contactable against a tissue surface proximate the fixation helix; and

a means for urging the displaceable member away from the lead axis.

19. The lead assembly of claim 18, wherein the lead assembly includes a stretchable tube, the displaceable member including a portion of the stretchable tube, the means for urging the displaceable member away from the lead axis configured to expand at least a portion of the stretchable tube away from the lead axis.

20. The lead assembly of claim 19, wherein the stretchable tube includes a portion having a first wall and a second wall that is thicker than the first wall, the displaceable member including at least a portion of the second wall.

21. The lead assembly of claim 18, wherein the displaceable member includes a protrusion that extends toward the lead axis, and the means for urging the displaceable member away from the lead axis is configured to push against the protrusion.

22. The lead assembly of claim 21, wherein the means for urging the displaceable member away from the lead axis further includes threads coupled to the lead body, a driver engageable on the threads, and a pusher coupled to the driver and contactable against the protrusion, wherein turning the driver on the threads moves the driver and pusher axially relative to the lead body to urge the pusher against the protrusion.

23. The lead assembly of claim 18, wherein the means for urging the displaceable member away from the lead axis includes threads connected to the lead body and a helical member engageable on the threads.

24. The lead assembly of claim 23, further comprising a tube coupled to the helical member, a portion of the tube extending from a distal end of the helical member and contacting the displaceable member.

25. The lead assembly of claim 23, wherein the helical member includes a first helical portion defining a gap between adjacent turns of the helical member, the means for urging the displaceable member away from the lead axis further comprising an interference member that extends through a portion of the gap between turns of the helical member and interferes with the threads.

26. The lead assembly of claim 23, wherein the helical member includes a first portion engageable on the threads and a second portion configured to interfere with the threads to urge the displaceable member away from the lead axis.

27. The lead assembly of claim 26, wherein the first portion has a first pitch and the second portion has a second pitch smaller than the first pitch.

28. The lead assembly of claim 18, wherein the displaceable member includes a flexible sleeve proximate the fixation helix and the means for urging the displaceable member away from the lead axis includes a means for folding the sleeve outwardly away from the lead axis, an outer surface of the sleeve contactable against the tissue wall to prevent perforation of the wall by the lead assembly.

29. The lead assembly of claim 28, wherein the sleeve includes a first end abutted against the lead body and a second end abuttable against the tissue wall.

30. A method comprising:

disposing a first member having a first cross-section in a lead assembly having a lead axis, an expandable passage, and a displaceable member proximate the expandable passage, the first member having at least one cross-sectional dimension larger than at least one corresponding cross-sectional dimension of the expandable passage;

urging the first member into the expandable passage in the lead assembly; and

urging the displaceable member away from the lead axis to expand the expandable passage.

31. The method of claim 30, wherein the lead assembly includes a plurality of displaceable members and urging the first member into the expandable passage in the lead assembly includes urging the first member against the plurality of displaceable members, wherein the plurality of displaceable members are displaced radially away from the lead axis.

32. The method of claim 31, further comprising engaging an outer surface of the lead assembly proximate the displaceable member against an inner wall of a blood vessel.

33. The method of claim 32, further comprising engaging a tooth on the outer surface of the lead assembly on an inner wall of a blood vessel.

34. The method of claim 30, wherein a fixation helix is coupled to the first member, the method further comprising engaging the fixation helix into a tissue wall and contacting the first member and displaceable member against the tissue wall.

35. The method of claim 34, wherein the fixation helix has a pitch and the lead assembly includes an internal helical protrusion having approximately the same pitch as the fixation helix, the at least one corresponding cross-sectional dimension of the expandable passage including an inner diameter of the internal helical protrusion, the fixation helix disposable in a gap defined by the internal helical protrusion, and the urging the displaceable member away from the lead axis including urging the first member against the internal helical protrusion.

36. The method claim 30, wherein the at least one cross-sectional dimension of the first member is a diameter of the first member, the at least one corresponding cross-sectional dimension of the expandable passage is a diameter of the passage, and urging the displaceable member away from the lead axis includes expanding the diameter of the passage.

37. The method of claim 30, wherein the lead assembly includes internal threads and a portion of the first member includes external threads, wherein the urging the first member into the expandable passage includes advancing the first member on the internal threads.

38. The method of claim 30, wherein a tooth is at least partially embedded in an outer surface of the lead assembly, and the urging the displaceable member away from the lead axis pushes a portion of the tooth out of the lead assembly.