Expandable fixation elements for subcutaneous electrodes

• US 7,349,742 B2
• Filed: 12/23/2003
• Issued: 03/25/2008
• Est. Priority Date: 04/11/2003
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Wagner, Darrell Orvin, Cates, Adam W., Heil, Ron, Lindstrom, Curtis Charles
• Primary Examiner(s): Getzow; Scott M.
• Application Number:
  US10/745,341
• Publication Number:
  US 20040230281A1
• Time in Patent Office: 1,554 Days
• Field of Search: 607115-130, 606/41, 606/108, 604/104, 600116-126
• US Class Current: 607/116
• CPC Class Codes: A61B 17/3203 Fluid jet cutting instruments
• CPC Class Codes: A61B 17/3415 for introducing tubes or catheters, e.g. gastrostomy tubes, drain catheters A61B17/3417 takes precedence; body piercing catheter guide needles A61M25/06
• CPC Class Codes: A61B 17/3417 Details of tips or shafts, e.g. grooves, expandable, bendable; Multiple coaxial sliding cannulas, e.g. for dilating syringe needles A61M5/32; dilators A61M29/00
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2017/320044 Blunt dissectors blunt suture needles A61B2017/06085
• CPC Class Codes: A61B 2017/320084 Irrigation sleeves
• CPC Class Codes: A61B 2018/00392 Transmyocardial revascularisation
• CPC Class Codes: A61B 2090/3945 Active visible markers, e.g. light emitting diodes
• CPC Class Codes: A61B 2217/005 with suction drainage system
• CPC Class Codes: A61B 2217/007 with irrigation system
• CPC Class Codes: A61B 90/30 Devices for illuminating a surgical field, the devices having an interrelation with other surgical devices or with a surgical procedure
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0568 with drug delivery
• CPC Class Codes: A61N 1/0587 Epicardial electrode systems; Endocardial electrodes piercing the pericardium
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36585 controlled by two or more physical parameters
• CPC Class Codes: A61N 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

Subcutaneous systems and leads may be fixed in tissue after placement by use of one or more expanding fixation elements. An expanding fixation element is provided on an implantable lead and configured to secure one or both of a subcutaneous electrode and the lead body within subcutaneous non-intrathoracic tissue. A delivery apparatus comprising a sheath may be included that is configured to introduce the lead to a desired subcutaneous non-intrathoracic location within the patient. A method of lead delivery typically involves introducing a sheath into a subcutaneous non-intrathoracic body location of a patient, providing a lead comprising a lead body and an electrode, and advancing the lead through the sheath and to the subcutaneous non-intrathoracic body location. The method further involves fixing the lead to subcutaneous non-intrathoracic tissue using an expanding fixation element and thereafter removing the sheath from the patient.

Claims

1. An implantable lead configured for placement within a tunnel formed in subcutaneous non-intrathoracic tissue, comprising:

a lead body;

a cardiac electrode supported by the lead body, the cardiac electrode configured for one or both of sensing cardiac activity and delivering cardiac stimulation energy from a location within the tunnel; and

an expandable fixation element provided on the implantable lead and comprising a material that undergoes a volumetric change when placed in subcutaneous non-intrathoracic tissue, the expandable fixation element configured to expand by body fluid absorption and to chronically secure one or both of the cardiac electrode and the lead body within subcutaneous non-intrathoracic tissue defining the tunnel by tissue in-growth into pores of the expandable fixation element.

2. The lead according to claim 1, wherein the expandable fixation element is provided on the cardiac electrode.

3. The lead according to claim 1, wherein the expandable fixation element comprises a sponge.

4. The lead according to claim 1, wherein the expandable fixation element comprises a scleral sponge.

5. The lead according to claim 1, wherein the expandable fixation element comprises a plurality of sponges arranged in a spaced relationship.

6. The lead according to claim 1, wherein the expandable fixation element comprises an expandable portion of the lead body.

7. The lead according to claim 6, wherein the expandable portion of the lead body comprises an additive in a polymer.

8. The lead according to claim 7, wherein the additive comprises glycerol.

9. The lead according to claim 6, wherein the expandable portion of the lead body comprises an expandable polymer.

10. The lead according to claim 9, wherein the expandable polymer comprises hydrogel.

11. The lead according to claim 1, wherein the expandable fixation element comprises an expandable collar coupled to the lead body.

12. The lead according to claim 11, wherein the expandable collar comprises an additive in a polymer.

13. The lead according to claim 12, wherein the additive comprises glycerol.

14. An implantable lead system configured for placement within a tunnel formed in subcutaneous non-intrathoracic tissue, comprising:

a lead comprising a lead body and a cardiac electrode, the lead configured for placement within the tunnel, the cardiac electrode configured for one or both of sensing cardiac activity and delivering cardiac stimulation energy from a location within the tunnel;

an expandable fixation element provided on the lead and comprising a material that undergoes a volumetric change when placed in subcutaneous non-intrathoracic tissue, the expandable fixation element configured to expand by body fluid absorption and to chronically secure one or both of the cardiac electrode and the lead body within subcutaneous non-intrathoracic tissue defining the tunnel by tissue in-growth into pores of the expandable fixation element; and

a delivery apparatus configured to introduce the lead to a desired subcutaneous non-intrathoracic location within the tunnel.

15. The lead system according to claim 14, wherein the expandable fixation element comprises one or more sponges.

16. The lead system according to claim 14, wherein the expandable fixation element comprises one or more scleral sponges.

17. The lead system according to claim 14, wherein a lumen of the delivery apparatus is dimensioned to compress the expandable fixation element while permitting axial displacement of the lead within the lumen.

18. The lead system according to claim 14, wherein the delivery apparatus comprises a sheath having a longitudinal pre-stress line arrangement to facilitate sheath separation during retraction of the sheath from the patient.

19. The lead system according to claim 14, wherein the expandable fixation element is provided on the cardiac electrode.

20. The lead system according to claim 14, wherein the expandable fixation element comprises a plurality of sponges arranged in a spaced relationship.

21. The lead system according to claim 14, wherein the expandable fixation element comprises an expandable portion of the lead body.

22. The lead system according to claim 21, wherein the expandable portion of the lead body comprises an additive in a polymer.

23. The lead system according to claim 22, wherein the additive comprises glycerol.

24. The lead according to claim 21, wherein the expandable portion of the lead body comprises an expandable polymer.

25. The lead system according to claim 24, wherein the expandable polymer comprises a hydrogel.

26. The lead system according to claim 14, wherein the expandable fixation element comprises an expandable collar coupled to the lead body.

27. The lead system according to claim 26, wherein the expandable collar comprises an additive in a polymer.

28. The lead system according to claim 27, wherein the additive comprises glycerol.

29. The lead according to claim 26, wherein the expandable collar comprises an expandable polymer.

30. The lead system according to claim 29, wherein the expandable polymer comprises a hydrogel.

31. A method of lead stabilization, comprising:

creating a tunnel in subcutaneous non-intrathoracic tissue of a patient;

providing a lead comprising a lead body, a cardiac electrode, and an expandable fixation element comprising a material that undergoes a volumetric change when placed in subcutaneous non-intrathoracic tissue, the cardiac electrode configured for one or both of sensing cardiac activity and delivering cardiac stimulation energy from a location within the tunnel;

advancing the lead into the tunnel; and

volumetrically expandably securing one or both of the lead body and the cardiac electrode within subcutaneous non-intrathoracic tissue defining the tunnel at a fixation site using the expandable fixation element.

32. The method according to claim 31, wherein the expandable fixation element expands to an effective diameter larger than the diameter of the lead body to engage the subcutaneous non-intrathoracic tissue at the fixation site.

33. The method according to claim 31, wherein the expandable fixation element comprises one or more expandable fixation elements that expand to fixedly engage the subcutaneous non-intrathoracic tissue at one or more fixation sites.

34. The method according to claim 31, further comprising modifying the position or orientation of the expandable fixation element when the lead is advanced within the lumen.

35. The method according to claim 34, wherein modifying the position or orientation comprises resiliently displacing the expandable fixation element when the lead is advanced within the lumen.

36. A method of lead delivery, comprising:

creating a tunnel in subcutaneous non-intrathoracic tissue of a patient;

introducing a sheath into the tunnel;

providing a lead comprising a lead body and a cardiac electrode configured for one or both of sensing cardiac activity and delivering cardiac stimulation energy from a location within the tunnel, the lead comprising an expandable fixation element that undergoes a volumetric change when placed in subcutaneous non-intrathoracic tissue;

advancing the lead through the sheath and into the tunnel;

volumetrically expandably fixing the lead within subcutaneous non-intrathoracic tissue defining the tunnel by tissue in-growth into pores of the expandable fixation element; and

removing the sheath from the patient.

37. The method according to claim 36, wherein removing the sheath comprises longitudinally splitting the sheath when removing the sheath from the patient.

38. The method according to claim 36, wherein removing the sheath comprises enabling the fixation element for expandably fixing the lead within the subcutaneous non-intrathoracic tissue.

39. The method according to claim 36, wherein advancing the lead through the sheath comprises modifying a position or an orientation of the expandable fixation element provided on one or both of the lead body and cardiac electrode.

40. The method according to claim 36, wherein advancing the lead through the sheath comprises compressing the expandable fixation element provided on one or both of the lead body and cardiac electrode.

41. The method according to claim 36, wherein fixing the lead comprises expanding a portion of the lead to fix one or both of the lead body and the electrode within the subcutaneous non-intrathoracic tissue.

42. An implantable lead configured for placement within a tunnel formed in subcutaneous non-intrathoracic tissue, comprising:

a lead body;

a cardiac electrode supported by the lead body, the cardiac electrode configured for one or both of sensing cardiac activity and delivering cardiac stimulation energy from a location within the tunnel; and

a volumetrically expandable portion provided on the implantable lead, the expandable portion configured to expand by bodily fluid absorption and to provide pores that promote tissue in-growth for chronic fixation to subcutaneous non-intrathoracic tissue defining the tunnel.

43. The lead according to claim 42, wherein the expandable portion comprises an additive in a polymer.

44. The lead system according to claim 43, wherein the additive comprises glycerol.

45. The lead according to claim 42, wherein the expandable portion comprises an expandable polymer.

46. The lead system according to claim 45, wherein the expandable polymer comprises a hydrogel.

47. The lead system according to claim 42, wherein the expandable portion comprises one or more sponges.

48. The lead system according to claim 42, wherein the expandable portion comprises one or more scleral sponges.

49. The lead system according to claim 42, wherein the expandable portion comprises an expandable collar coupled to the implantable lead.

50. The lead according to claim 42, wherein the expandable portion comprises first and second additives, the first additive configured to provide expansion and the second additive configured to provide the pores.

51. The lead according to claim 42, wherein the expandable portion comprises a polymer having first and second additive concentrations, the first additive concentration configured to provide expansion and the second additive concentration configured to provide the pores.