Extractable implantable medical lead

• US 6,801,809 B2
• Filed: 05/14/2001
• Issued: 10/05/2004
• Est. Priority Date: 02/22/2000
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Waldhauser, Steven L., Keeney, Kenneth W., Taylor, Catherine E., Laske, Timothy G., Stewart, Mark T.
• Primary Examiner(s): EVANISKO, GEORGE ROBERT
• Application Number:
  US09/854,999
• Publication Number:
  US 20010044646A1
• Time in Patent Office: 1,240 Days
• Field of Search: 607/116, 607/119, 607/122, 607/128, 607/123, 607/126
• US Class Current: 607/126
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 2001/0578 having means for removal or extraction

Abstract

A medical electrical lead with a tip-ring assembly optimized to resist damage during extraction. The lead includes an elongated plastic tube and at least two elongated conductors mounted in the plastic tube. A tip-ring assembly is mounted to the distal end of the tube, the tip-ring assembly including a ring electrode coupled to one of the conductors, a tip electrode located distal to the ring electrode and coupled to another of the conductors and two molded plastic components separately fabricated of a plastic harder than the plastic tube, adhered to one another and together defining a circumferential groove in which the ring electrode is located and mechanically coupled to the tip electrode. The tip electrode may be provided with a proximally extending electrode shank covered by a tine sleeve which is fabricated of a plastic softer than the molded plastic components and is adhered to more distally located molded plastic component. The more distally located molded plastic component preferably overlaps the electrode shank to provide a stronger structure.

Claims

1. A medical electrical lead comprising:

a first elongated plastic tube having proximal and distal ends and a cylindrical outer surface;

a first elongated conductor, a second elongated conductor and a third elongated conductor mounted in said first plastic tube;

a first coil electrode having en outer diameter, mounted exterior to and around the cylindrical outer surface of the first tube and coupled to the first conductor;

a second elongated plastic tube having an outer diameter approximately equal to the outer diameter of the first coil electrode, mounted exterior to and around the cylindrical outer surface of the first tube adjacent the first coil electrode and extending proximally therefrom and not overlapping any portion of the first coil electrode exterior to the first tube; and

a tip-ring assembly mounted to the distal end of the first tube, the tip-ring assembly comprising;

a ring electrode coupled to the second conductor;

a tip electrode located distal to the ring electrode and coupled to the third conductor; and

two molded plastic components separately fabricated of a plastic harder than the first tube, adhered to one another and together defining a circumferential groove in which the ring electrode is located, a more distally located one of the molded plastic components mechanically coupled to the tip electrode.

2. A lead according to claim 1, further comprising:

a second coil electrode having an outer diameter approximately equal to the outer diameter of the first coil electrode, mounted exterior to and around the cylindrical outer surface of the first tube proximal to the first coil electrode; and

wherein the second elongated plastic tube extends to a point adjacent the second coil electrode and does not overlap any portion of the second coil electrode exterior to the first tube.

3. A lead according to claim 2 further comprising:

a third elongated plastic tube having an outer diameter approximately equal to the outer diameter of the second coil electrode, mounted exterior to and around the cylindrical outer surface of the first tube adjacent the second coil electrode and extending proximally therefrom and not overlapping any portion of the second coil electrode exterior to the first tube.

4. A lead according to claim 1 or claim 2 or claim 3 wherein the first tube is an extruded multi-lumen tube.

5. A lead according to claim 1 wherein the tip electrode comprises a proximally extending electrode shank and further comprising a tine sleeve fabricated of a plastic softer than the molded plastic components and mounted around said electrode shank.

6. A lead according to claim 5 wherein the more distally located one of the molded plastic components is adhered to the tine sleeve.

7. A lead according to claim 6 wherein the more distally located molded plastic component overlaps the electrode shank.

8. An implantable pacing and defibrillation lead, comprising:

a multi-lumen lead body Including a proximal end and a distal end;

two or more connector assemblies;

a sleeve coupling the proximal end of the lead body to the two or more connector assemblies;

a cable conductor extending through a lumen of the multilumen lead body;

a coiled defibrillation electrode surrounding an outer periphery of the lead body, and coupled to the cable conductor; and

an overlay tubing surrounding the outer periphery of the lead body and extending proximally from the coiled defibrillation electrode to terminate at a position in proximity to a distal end of the sleeve;

wherein the coiled defibrillation electrode has an outer diameter which is approximately equal to an outer diameter of the overlay tubing.

9. The lead of claim 8, wherein the multilumen lead body is formed of silicone rubber.

10. The lead of claim 8, wherein the multilumen lead body is formed of polyurethane.

11. The lead of claim 8, wherein the overlay tubing is formed of silicone rubber.

12. The lead of claim 8, wherein the overlay tubing is formed of polyurethane.

13. The lead of claim 8, wherein the two or more connector assemblies include an IS-1 connector assembly.

14. The lead of claim 8, further comprising:

a second cable conductor extending though another lumen of the lead body;

a second coiled defibrillation electrode surrounding an outer periphery of the lead body, positioned distal to the coiled defibrillation electrode and coupled to the second cable conductor; and

a second overlay tubing surrounding the outer periphery of the lead body and extending distally from the coiled defibrillation electrode to terminate at a position in proximity to a proximal end of the second coiled defibrillation electrode;

wherein the second overlay tubing has an outer diameter approximately equal to an outer diameter of the second coiled defibrillation electrode.

15. The lead of claim 8, wherein the position at which the overlay tubing terminates is located beneath the sleeve, proximal to the distal end of the sleeve.

16. An implantable pacing and defibrillation lead, comprising:

a lead body including a proximal end and a distal end;

one or more connector assemblies;

a sleeve coupling the proximal end of the lead body to the one or more connector assemblies;

a conductor extending through a lumen of the lead body;

a coiled defibrillation electrode surrounding an outer periphery of the lead body and coupled to the conductor; and

an overlay tubing surrounding the outer periphery of the lead body and including a first end and a second end;

wherein the first end of the overlay tubing is positioned in proximity to the coiled defibrillation electrode and the second end of the overlay tubing is positioned in proximity to the sleeve; and

the coiled defibrillation electrode has an outer diameter which is approximately equal to an outer diameter of the overlay tubing.

17. The lead of claim 16, wherein the overlay tubing is formed of silicone rubber.

18. The lead of claim 16, wherein the overlay tubing is formed of polyurethane.

19. The lead of claim 16, wherein the second end of the overlay tubing is further positioned beneath the sleeve.

20. The lead of claim 16, further comprising:

a second conductor extending though another lumen of the lead body;

a second coiled defibrillation electrode surrounding an outer periphery of the lead body, positioned distal to the coiled defibrillation electrode and coupled to the second conductor; and

a second overlay tubing surrounding the outer periphery of the lead body and including a first end and a second end;

wherein the first end of the second overlay tubing is positioned in proximity to the second coiled defibrillation electrode and the second end of the overlay tubing is positioned in proximity to the coiled defibrillation electrode;

and the first end of the second overlay tubing has an outer diameter approximately equal to the outer diameter of the second coiled defibrillation electrode.