Pressure-sensitive flexible polymer bipolar electrode

• US 9,949,792 B2
• Filed: 07/23/2012
• Issued: 04/24/2018
• Est. Priority Date: 12/29/2006
• Status: Active Grant

• Current Assignee: St. Jude Medical (Abbott Laboratories Incorporated)
• Original Assignee: St. Jude Medical (Abbott Laboratories Incorporated)
• Inventors: Paul, Saurav, Puryear, Harry A., Thao, Riki, Cao, Hong
• Primary Examiner(s): Della, Jaymi
• Assistant Examiner(s): KIM, EUN HWA
• Application Number:
  US13/555,929
• Publication Number:
  US 20130190754A1
• Time in Patent Office: 2,101 Days
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/00023 closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00875 Resistance or impedance

Abstract

The present invention is directed to bipolar ablation systems. A bipolar electrode system for ablation therapy is disclosed, including a pressure-sensitive conducting composite layer and a pair of electrodes in electrical conductive contact or communication with the pressure-sensitive conducting composite layer. Energy (e.g., ablation energy) is delivered via the pressure-sensitive conductive composition when sufficient pressure is applied to transform the pressure-sensitive conductive composite to an electrical conductor. An electrically insulative flexible layer, which may include a passageway for a fill material is also disclosed. In some embodiments, the systems can also be used for targeted delivery of compounds, such as drugs, using a bipolar electrode.

Claims

1. A catheter, comprising:

a catheter shaft comprising a distal portion and a proximal portion; and

an electrode assembly coupled to the distal portion,

the electrode assembly comprising

an exterior configured to engage target tissue and configured to bend and conform to a compliant tissue wall of the target tissue;

first and second electrodes on the exterior;

first and second pressure-sensitive conductive composite layers; and

a pair of electrical wires in electrical contact with the first and second pressure-sensitive conductive composite layers;

wherein the first pressure-sensitive conductive composite layer is disposed radially inward of and in electrical communication with said first electrode and the second pressure-sensitive conductive composite layer is disposed radially inward of and in electrical communication with said second electrode;

wherein the electrode assembly is configured to channel ablative energy to a first portion of the exterior of the electrode assembly while not channeling ablative energy to a second portion of the exterior of the electrode assembly when the first portion—

is in contact with the target tissue and the second portion is not in contact with the target tissue.

2. The catheter of claim 1, wherein the electrode assembly comprises a porous material such that a fluid may pass therethrough.

3. The catheter of claim 1, wherein the electrode assembly is further configured to allow a fluid to exit from the electrode assembly between the first and second electrode.

4. The catheter of claim 1, wherein the electrode assembly is further configured to allow a fluid to exit from the electrode assembly adjacent the first and second electrode.

5. The catheter of claim 1, wherein the ablative energy from an ablative energy source coupled to said pair of electrical wires is channeled to the first portion of the exterior via corresponding first portion of said first and second pressure-sensitive conductive composite layers when sufficient pressure is applied thereto and thereby transform said corresponding first portion of said first and second pressure-sensitive conductive composite layers into electrical conductors.

6. The catheter of claim 5 wherein said second portion of the exterior is associated with a corresponding second portion of said pressure-sensitive conductive composite layer.

7. The catheter of claim 5 further comprising:

an electrically insulative flexible layer adjacent the first and second pressure-sensitive conductive composite layers.

8. The catheter of claim 7 further comprising:

a sensor configured to monitor a temperature and is located in said electrically insulative flexible layer.

9. The catheter of claim 7 further comprising:

a heat sink thermally coupled to one of said first and second pressure-sensitive conductive composite layers and said electrically insulative flexible layer.

10. The catheter of claim 5 wherein said first and second pressure-sensitive conductive composite layers comprises a quantum tunneling composite member.

11. The catheter of claim 5 wherein said first electrode comprises a circumferentially-extending ring of electrically-conductive material wherein said outside surface of said first electrode is a first outside surface, said second electrode comprises a circumferentially-extending ring of electrically-conductive material having a second outside surface, said exterior of said electrode assembly including said first and second outside surfaces.

12. The catheter of claim 11 wherein said first and second pressure-sensitive conductive composite layers comprises at least a first annular portion radially-inwardly of said first electrode and a second annular portion radially-inwardly of said second electrode, said first electrode being longitudinally offset from said second electrode.

13. The catheter of claim 12 further comprising a tip electrode at a distal end of said catheter shaft and located distal of said first and second electrodes, said catheter further comprising a further electrical conducting element coupled to said tip electrode.

14. A catheter, comprising:

a catheter shaft comprising a distal portion and a proximal portion; and

an electrode assembly coupled to the distal portion including;

first and second electrodes whose outside surfaces are configured to engage target tissue;

first and second pressure-sensitive conductive composite layers disposed radially inward of said first and second electrodes, respectively, and configured as electrical insulators in an absence of a predetermined applied pressure and further configured as electrical conductors in a presence of the predetermined applied pressure; and

pair of electrical conducting wires in contact with the first and second pressure-sensitive conductive composite layers and coupled to an ablative energy source;

said electrode assembly includes (i) a conductive zone corresponding to a portion of said outside surfaces of said first and second electrodes that are subject to said predetermined applied pressure when in contact with said target tissue and in which ablative energy is delivered and (ii) a complementary insulative zone where none of the ablative energy is delivered when said complementary insulative zone is not subject to said predetermined applied pressure when it is not in contact with said target tissue;

wherein the ablative energy from the ablative energy source is channeled to the conductive zone via a corresponding first portion of said first and second pressure-sensitive conductive composite layers when the predetermined pressure is applied thereto to transform the corresponding first portion of said first and second pressure-sensitive conductive composite layers into electrical conductors.

15. The catheter of claim 14, further comprising a tip electrode coupled with a further electrical conducting element.

16. The catheter of claim 14, wherein said first and second pressure-sensitive conductive composite layers comprises a quantum tunneling composite member.

17. A catheter, comprising:

a catheter shaft comprising a distal portion and a proximal portion; and

an electrode assembly coupled to the distal portion including;

first and second electrodes having respective outside surfaces configured to engage target tissue;

first and second pressure-sensitive conductive composite layers being arranged relative to said first and second electrodes, respectively; and

first and second electrical conducting wires extending to a proximal end of said catheter and are configured for connection to an electrical apparatus, wherein the first and second electrical wires are in contact with the first and second pressure-sensitive conductive composite layers, respectively;

said first pressure-sensitive conductive composite layer being configured to selectively couple said first electrical conducting wire to said first electrode when said outside surface of said first electrode experiences a predetermined pressure applied thereto and configured to not selectively couple said first electrical conducting wire to said first electrode when said outside surface of said first electrode does not experience said predetermined pressure applied thereto,

said second pressure-sensitive conductive composite layer being configured to selectively couple said second electrical conducting wire to said second electrode when said outside surface of said second electrode experiences said predetermined pressure applied thereto and configured to not selectively couple said second electrical conducting wire to said second electrode when said outside surface of said second electrode does not experience said predetermined pressure applied thereto.

18. The catheter of claim 17, wherein said first and second pressure-sensitive conductive composite layers are configured as electrical insulators in absence of the predetermined applied pressures and electrical conductors in presence of the predetermined applied pressure.