Helical fixation elements for subcutaneous electrodes

• US 7,499,758 B2
• Filed: 12/18/2003
• Issued: 03/03/2009
• 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: Kelley, Pete, Shiroff, Jason Alan, Cates, Adam W., Heil, Ron, Lindstrom, Curtis Charles
• Primary Examiner(s): Manuel; George
• Application Number:
  US10/739,918
• Publication Number:
  US 20040230280A1
• Time in Patent Office: 1,902 Days
• Field of Search: 607/8, 607/5, 607/119, 607/4, 607/115, 607/116, 607/122, 607126-128, 607/131, 607/118, 607/134
• US Class Current: 607/126
• 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 leads that incorporate active fixation elements including, for example, helical coils, provide for fixation of cardiac lead components within a patient. An implantable lead includes a lead body with a supported electrode configured for subcutaneous non-intrathoracic placement within a patient. A fixation element is provided on the implantable lead and configured to actively secure one or both of the subcutaneous electrode and the lead body in tissue. A delivery apparatus comprising a sheath may be employed that is configured to introduce the lead to a desired subcutaneous non-intrathoracic location. Lead delivery typically involves introducing a sheath into a subcutaneous non-intrathoracic body location of a patient, providing a lead supporting an electrode, advancing the lead through the sheath, actively fixing the lead to tissue, and thereafter removing the sheath from the patient.

Claims

1. An implantable lead, comprising:

a lead body comprising a sheath, the sheath having a proximal end, a distal end, and a distal tip terminating the distal end, the distal tip having a body cross-sectional diameter;

a delivery sheath having a lumen, a distal end, and a distal tip terminating the distal end, the lead body configured to translate longitudinally within the lumen;

a cardiac electrode supported by the lead body, the cardiac electrode configured for subcutaneous non-intrathoracic placement within a patient; and

a fixation element provided on the distal tip of the sheath of the lead body, the fixation element comprising a helical coil configured to be deployed distal of the distal tip of the sheath of the lead body, the helical coil including a tissue penetrating tip, a portion of the helical coil configured to extend radially beyond the body cross-sectional diameter of the distal tip of the sheath of the lead body and actively secure the lead in subcutaneous non-intrathoracic tissue in a deployed configuration, the helical coil compressed by, and substantially contained within, the lumen of the delivery sheath in a non-deployed configuration, the implantable lead configured such that retraction of the distal tip of the delivery sheath past the distal tip of the sheath of the lead body to a location proximal of the distal tip of the sheath of the lead body transitions the helical coil from the non-deployed configuration to the deployed configuration.

2. The lead according to claim 1, wherein the fixation element has a fixation element cross-sectional diameter, and wherein the fixation element cross-sectional diameter is larger than the body cross-sectional diameter of the distal tip of the sheath of the lead body.

3. The lead according to claim 1, wherein the helical coil is coupled to the lead body to facilitate independent rotation of the helical coil relative to the lead body.

4. The lead according to claim 1, wherein a cross-sectional diameter of the helical coil is substantially equal to the body cross-sectional diameter of the distal tip of the sheath while in the non-deployed configuration.

5. The lead according to claim 1, wherein the distal tip of the sheath of the lead body has a longitudinal axis and the fixation element has a fixation element longitudinal axis, and wherein the longitudinal axis of the distal tip of the sheath is non-coincident with respect to the fixation element longitudinal axis in the deployed configuration.

6. The lead according to claim 1, wherein the helical coil is formed from a shape memory alloy.

7. The lead according to claim 1, wherein the fixation element is formed from a material having a spring memory.

8. The lead according to claim 1, wherein the fixation element is electrically insulated from the electrode.

9. The lead according to claim 1, wherein the fixation element is part of the electrode.

10. The lead according to claim 1, wherein:

the distal tip of the sheath of the lead body comprises a longitudinal axis; and

the fixation element comprises a longitudinal axis aligned in a non-coaxial parallel relationship with respect to the longitudinal axis of the distal tip of the sheath of the lead body in the deployed configuration.

11. The lead according to claim 1, wherein the helical coil has a non-uniform cross-sectional diameter along the helical coil.

12. An implantable lead system, comprising:

a lead body comprising a sheath, the sheath having a proximal end, a distal end, and a distal tip terminating the distal end, the distal tip of the sheath having a body cross-sectional diameter and a longitudinal axis;

a cardiac electrode supported by the lead body, the cardiac electrode configured for subcutaneous non-intrathoracic placement within a patient;

a fixation element provided on the distal tip of the sheath and extending distal of the distal tip of the sheath, the fixation element comprising a longitudinal axis non-coincident with the longitudinal axis of the distal tip of the sheath, and a helical coil including a tissue penetrating tip and configured to actively secure the lead body or electrode in subcutaneous non-intrathoracic tissue, a portion of the helical coil configured to radially extend beyond the body cross-sectional diameter of the distal tip of the sheath.

13. The lead system according to claim 12, further comprising a delivery apparatus comprising a delivery sheath, the delivery sheath having a proximal end of the delivery sheath, a distal end of the delivery sheath, a distal tip of the delivery sheath terminating the distal end of the delivery sheath, and a lumen extending between the proximal end of the delivery sheath and the distal tip of the delivery sheath, the delivery sheath configured to:

contain the lead body within the lumen of the delivery sheath, the helical coil compressed by the lumen of the delivery sheath;

introduce the lead to a desired subcutaneous non-intrathoracic location within the patient; and

separate from the lead body and leave the lead body in the desired subcutaneous non-intrathoracic location, wherein the implantable lead system is configured such that the helical coil radially springs beyond the body cross-sectional diameter of the distal tip of the sheath of the lead body upon retraction of the distal tip of the delivery sheath past the fixation element to a location proximal of the distal tip of the sheath of the lead body.

14. The lead system according to claim 12, wherein the helical coil is coupled to the lead body to facilitate independent rotation of the helical coil relative to the lead body.

15. The lead according to claim 12, wherein

the fixation element comprises a longitudinal axis aligned in a non-coaxial parallel relationship with respect to the longitudinal axis of the distal tip of the sheath of the lead body.

16. The lead system according to claim 12, wherein the fixation element has a fixation element cross-sectional diameter, and wherein the fixation element cross-sectional diameter is larger than the body cross-sectional diameter of the distal tip of the sheath of the lead body.

17. The lead system according to claim 12, wherein the helical coil is formed from a shape memory alloy.

18. The lead system according to claim 12, wherein the fixation element is formed from a material having a spring memory.

19. The lead system according to claim 12, wherein the fixation element is electrically insulated from the electrode.

20. The lead system according to claim 12, wherein the fixation element is part of the electrode.

21. The lead system according to claim 12, wherein the lumen of the delivery sheath is dimensioned to compress the fixation element while permitting axial displacement of the lead within the lumen.

22. An implantable lead, comprising:

a lead body comprising a sheath, the sheath having a proximal end, a distal end, and a distal tip terminating the distal end of the sheath and the lead body, the distal tip having a body cross-sectional diameter;

a delivery sheath having a lumen, a proximal end of the delivery sheath, a distal end of the delivery sheath, and a distal tip terminating the distal end of the delivery sheath, the lead body translatable within the lumen of the delivery sheath;

a cardiac electrode supported by the lead body, the cardiac electrode configured for subcutaneous non-intrathoracic placement in a patient; and

means for actively fixing the lead body within subcutaneous non-intrathoracic tissue, the active fixing means comprising helical fixing means disposed on the distal tip of the sheath of the lead body and extending distal of the distal tip of the sheath of the lead body, the helical fixing means configured to penetrate subcutaneous tissue and radially extend beyond the body cross-sectional diameter of the distal tip of the sheath of the lead body in a deployed configuration upon retraction of the distal tip of the delivery sheath to a location proximal of the distal tip of the sheath of the lead body, the helical coil compressed by, and contained within, the lumen of the delivery sheath in a non-deployed configuration.

23. The lead according to claim 22, wherein the active fixing means comprises means for rotatably fixing one or both of the lead body and the cardiac electrode within the subcutaneous non-intrathoracic tissue.

24. The lead according to claim 22, further comprising means for modifying a position or an orientation of the fixing means.

25. The lead according to claim 22, wherein the lumen of the delivery means is dimensioned to at least partially collapse the fixing means while permitting axial displacement of the lead body within the lumen.