Medical lead termination sleeve for implantable medical devices
View Patent ↗A wire and electrode combination suitable for use with implanted medical devices, and a method for coupling the wire and electrode to achieve a robust electrical connection suitable for use with such medical devices are disclosed. The apparatus employs a wire that is optimized for strength, an electrode optimized for biocompatibility, and a termination sleeve with a closed distal end for coupling the wire to the electrode, while eliminating the potential for galvanic corrosion, enhancing weld quality, and facilitating manufacture of the apparatus. The method involves compressing the sleeve to engage the wire at two locations, where contact between the sleeve and wire at the first location seals the interior of the sleeve, and contact between the sleeve and wire at the second location electrically couples the wire to the sleeve. The sleeve, which is easier to manipulate than the wire, is then spot welded to the electrode.
1. A medical device lead, comprising:
a lead wire having a lead wire end supporting a conductor and a cover; and
a sleeve having an axial sleeve length and an internal hollow portion communicating with a sleeve opening through which the lead wire end extends to dispose the conductor and the cover within the internal hollow portion, the sleeve having a first portion and a second portion each disposed along the axial sleeve length of the sleeve and a third portion disposed between the first portion and the second portion, the third portion defining a third portion sleeve outer dimension about a sleeve axis, the sleeve at the first portion being deformed to sealingly engage the cover and the sleeve at the second portion being deformed to engage the conductor,
wherein at least one of the first portion and the second portion defines a deformed sleeve outer dimension of the sleeve about the sleeve axis, the deformed sleeve outer dimension being less than the third portion sleeve outer dimension.
2. The medical device lead of claim 1 , wherein the conductor includes at least one wire, the sleeve at the second portion being mechanically deformed to engage the at least one wire.
3. The medical device lead of claim 1 , wherein the conductor includes a plurality of wires, the sleeve at the second portion being mechanically deformed to engage at least one wire of the plurality of wires.
4. The medical device lead of claim 1 , wherein the hollow portion defines an inner volume, the deformed sleeve at the first portion providing a seal between the inner volume and the sleeve opening.
5. The medical device lead of claim 1 , wherein the conductor comprises a nickel cobalt alloy.
6. The medical device lead of claim 1 , wherein the sleeve comprises a platinum iridium alloy.
7. The medical device lead of claim 1 , wherein the conductor is a drawn filled tube composite.
8. The medical device lead of claim 1 , wherein the conductor is a drawn filled tube (DFT) wire.
9. The medical device lead of claim 1 , wherein the deformed sleeve at the first portion is a crimped first portion and the deformed sleeve at the second portion is a crimped second portion.
10. The medical device lead of claim 1 , wherein an engagement provided between the lead wire and the sleeve is devoid of welds.
11. The medical device lead of claim 1 , wherein a conductive engagement provided within the deformed sleeve at the second portion of the sleeve is contained within a sealed portion of the internal hollow portion.
12. An electrode assembly, comprising:
an electrode;
a lead wire having a lead wire end supporting a conductor and a cover; and
a sleeve coupling the electrode to the lead wire, the sleeve having an axial sleeve length and an internal hollow portion communicating with a sleeve opening through which the lead wire end extends to dispose the conductor and the cover within the internal hollow portion, the sleeve having a first portion and a second portion each disposed along the axial sleeve length of the sleeve and a third portion disposed between the first portion and the second portion, the third portion defining a third portion sleeve outer dimension about the sleeve axis, the sleeve at the first portion being deformed to sealingly engage the cover and the sleeve at the second portion being deformed to engage the conductor,
wherein at least one of the first portion and the second portion defines a deformed sleeve outer dimension of the sleeve about the sleeve axis, the deformed sleeve outer dimension being less than the third portion sleeve outer dimension.
13. The electrode assembly of claim 12 , wherein the conductor is a drawn filled tube composite.
14. The electrode assembly of claim 12 , wherein the conductor is a drawn filled tube (DFT) wire.
15. The electrode assembly of claim 12 , wherein the deformed sleeve at the first portion is a crimped first portion and the deformed sleeve at the second portion is a crimped second portion.
16. The electrode assembly of claim 12 , wherein the electrode and the sleeve comprise a same material.
17. The electrode assembly of claim 13 , wherein an engagement provided between the lead wire and the sleeve is devoid of welds.
18. The electrode assembly of claim 13 , wherein a conductive engagement provided within the deformed sleeve at the second portion of the sleeve is contained within a sealed portion of the internal hollow portion.
19. A medical device lead comprising:
a lead wire having a lead end supporting a conductor and a cover, the cover defining a cover outer diameter and the conductor defining a conductor outer diameter, the cover outer diameter being greater than the conductor outer diameter; and
a sleeve having an axial sleeve length and an internal hollow portion communicating with a sleeve opening through which the lead wire end extends to dispose the conductor and the cover within the internal hollow portion, the sleeve having a first portion and a second portion each disposed along the axial sleeve length of the sleeve with the first portion aligned with the cover and the second portion aligned with the conductor,
wherein the internal hollow portion has a pre-deformation state and a post-deformation state such that the internal hollow portion in the pre-deformation state has a uniform pre-deformation inner diameter extending along the axial sleeve length from the first portion to the second portion and the internal hollow portion in the post-deformation state has a plurality of post-deformation inner diameters extending along the axial sleeve length from the first portion to the second portion, and
wherein at least a portion of the sleeve in the post-deformation state is in contact with the conductor.
20. The medical device lead of claim 19 , wherein the conductor comprises at least one of a nickel cobalt alloy, a drawn filled tube composite, and a drawn filled tube (DFT) wire.
21. The medical device lead of claim 19 , wherein the sleeve comprises a platinum iridium alloy.