Body implantable lead with improved tip electrode assembly

• US 6,766,203 B2
• Filed: 04/05/2001
• Issued: 07/20/2004
• Est. Priority Date: 04/05/2001
• Status: Expired due to Fees

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Chitre, Yougandh, Doan, Phong D., Helland, John R.
• Primary Examiner(s): Jastrzab, Jeffrey R.
• Assistant Examiner(s): Oropeza, Frances P.
• Application Number:
  US09/828,353
• Publication Number:
  US 20020147488A1
• Time in Patent Office: 1,202 Days
• Field of Search: 600/372-374, 600/377, 600/393, 607/116, 607/119, 607/120, 607/122
• US Class Current: 607/122
• CPC Class Codes: A61N 1/0565 Electrode heads
• CPC Class Codes: A61N 2001/0578 having means for removal or extraction

Abstract

A body implantable lead assembly adapted to transmit electrical tissue stimulating signals between a proximal end portion of the lead assembly and a distal end portion of the lead assembly includes an electrical conductor extending between the proximal and distal end portions of the lead assembly for transmitting the electrical signals. The conductor has an enlarged, preferably ball shaped distal extremity comprising a termination element. The lead assembly includes a tip electrode having a proximal portion, a proximal extremity, a distal portion and a distal extremity, the distal extremity comprising an active electrode surface. At least the proximal portion of the tip electrode comprises a tubular structure, the tubular proximal portion having an inside diameter slightly smaller than the termination element on the distal extremity of the conductor. The tubular proximal portion of the tip electrode has formed within the wall thereof at least one longitudinally oriented, keyhole-shaped opening. The opening comprises an aperture and a longitudinal slot connecting the aperture and the proximal extremity of the tip electrode, the aperture being smaller than the termination element. The termination element is seated in the aperture of the at least one opening and one or welds may be added between the periphery of the aperture and the termination element to enhance the electrical and mechanical integrity of the connection therebetween.

Claims

1. A body implantable lead adapted to transmit electrical signals between a proximal end portion of the lead and a distal end portion of the lead and to thereby stimulate selected body tissue and/or sense electrical signals therefrom, the lead extending in a longitudinal direction and comprising:

an elongated electrical conductor extending between said proximal and distal end portions of the lead assembly for transmitting the electrical signals, the conductor having an enlarged distal extremity; and

an electrically conductive tip electrode having a distal portion including a distal extremity defining an active exterior electrode surface, the tip electrode further having a proximal portion and a proximal extremity, at least the proximal portion of the tip electrode comprising a longitudinally extending, generally tubular structure having an interior bounded by a wall, the wall defining at least one through-aperture, the at least one aperture being smaller than the enlarged distal extremity of the conductor, a longitudinal slot extending from the at least one aperture to the proximal extremity of the tip electrode, the enlarged distal extremity of the conductor being disposed within the interior of the tube and seated within the at least one aperture.

2. The body implantable lead, as defined in claim 1, in which:

the at least one through-aperture has a periphery; and

the enlarged distal extremity of the conductor is welded to the tube along the periphery of the at least one through-aperture.

3. The body implantable lead, as defined in claim 1, in which:

the wall defines two through-apertures, the apertures being substantially diametrically opposed, a longitudinal slot extending from each of the apertures to the proximal extremity of the tip electrode.

4. The body implantable lead, as defined in claim 3, in which:

each of the two through-apertures has a periphery; and

the enlarged distal extremity of the conductor is welded to the tube along the periphery of at least one of two through-apertures.

5. The body implantable lead, as defined in claim 1, in which:

the enlarged distal extremity is ball shaped.

6. The body implantable lead, as defined in claim 5, in which:

a diameter of the enlarged distal extremity is greater than an inner diameter of the generally tubular structure.

11. The body implantable lead, as defined in claim 6, in which:

a diameter of the ball shaped termination element is greater than an inner diameter of the interior bounded by the wall.

7. A body implantable lead adapted to transmit electrical signals between a proximal end portion of the lead and a distal end portion of the lead and to thereby stimulate selected body tissue and/or sense electrical signals therefrom, the lead extending in a longitudinal direction and comprising:

an elongated electrical conductor extending between said proximal and distal end portions of the lead assembly for transmitting the electrical signals, the conductor having a diameter and a distal extremity;

a generally ball shaped termination element carried by the distal extremity of the conductor, the ball shaped termination element having a diameter larger than the diameter of the conductor, and

an electrically conductive tip electrode having a distal end portion including a distal extremity defining a tissue stimulating exterior electrode surface, the tip electrode further having a proximal end portion and a proximal extremity, at least the proximal portion of the tip electrode comprising a longitudinally extending tube having an interior bounded by a wall, the wall defining at least one through-aperture defined by a rim having a diameter smaller than the diameter of the ball shaped termination element, a longitudinal slot extending from the at least one aperture to the proximal extremity of the tip electrode, the termination element carried by the distal extremity of the conductor being disposed within the proximal portion of the tip electrode in engagement with the rim of the at least one aperture.

8. The body implantable lead, as defined in claim 7, in which:

the at least one through-aperture has a periphery; and

the enlarged distal extremity of the conductor is welded to the tube along the periphery of the at least one through-aperture.

9. The body implantable lead, as defined in claim 7, in which:

the wall defines two though-apertures, the apertures being diametrically opposed, a longitudinal slot extending from each of the apertures to the proximal extremity of the tip electrode.

10. The body implantable lead, as defined in claim 9, in which:

each of the two through-apertures has a periphery; and

the enlarged distal extremity of the conductor is welded to the tube along the periphery of at least one of two through-apertures.

12. A passive fixation body implantable lead assembly adapted to transmit electrical signals between a proximal end portion of the lead assembly and a distal end portion of the lead assembly and to thereby stimulate selected body tissue and/or sense electrical signals therefrom, the lead assembly having a longitudinal axis and comprising:

an electrical conductor extending between said proximal and distal end portions of the lead assembly for transmitting the electrical signals, the conductor having an enlarged distal end;

a sheath of insulative, biocompatible material enclosing the electrical conductor for electrically insulating the conductor from body tissue and body fluids, the insulative sheath having a distal extremity;

a tip electrode having a proximal portion, a proximal extremity, a distal portion and a distal extremity, the distal extremity comprising an active electrode surface, the tip electrode comprising a generally tubular structure having a wall with at least one longitudinally oriented keyhole-shaped opening therein, the opening comprising an aperture in the proximal portion of the tip electrode and a slot connecting the aperture and the proximal extremity of the tip electrode, the aperture being smaller than the enlarged distal end of the conductor, the enlarged distal end of the conductor being seated in the aperture; and

a drug dispensing member disposed with the distal portion of the tubular tip electrode.

13. The body implantable lead assembly, as defined in claim 12, in which:

the at least one through-aperture has a periphery; and

the enlarged distal extremity of the conductor is welded to the tube along the periphery of the at least one through-aperture.

14. The body implantable lead assembly, as defined in claim 12, in which:

the wall defines two through-apertures, the apertures being diametrically opposed, a longitudinal slot extending from each of the apertures to the proximal extremity of the tip electrode.

15. The body implantable lead assembly, as defined in claim 14 which:

each of the two through-apertures has a periphery; and

the enlarged distal extremity of the conductor is welded to the tube along the periphery of at least one of two through-apertures.

16. The body implantable lead, as defined in claim 12, in which:

the enlarged distal extremity is ball shaped.

17. The body implantable lead, as defined in claim 16, in which:

a diameter of the bell shaped termination element is greater than an inner diameter of the tubular structure.