Medical device with sensor cooperating with expandable member

• US 20030176816A1
• Filed: 01/31/2003
• Published: 09/18/2003
• Est. Priority Date: 07/08/1997
• Status: Active Grant

• Current Assignee: Alan K. Schaer, Edward L. Carcamo, Guillermo P. Picazo, Kevin J. Taylor, Mark A. Maguire, Michael D. Lesh, Oʼsullivan, Martin F.
• Original Assignee: Alan K. Schaer, Edward L. Carcamo, Guillermo P. Picazo, Kevin J. Taylor, Mark A. Maguire, Michael D. Lesh, Oʼsullivan, Martin F.
• Inventors: OʼSullivan, Martin F., Lesh, Michael D., Schaer, Alan K., Maguire, Mark A., Carcamo, Edward L., Taylor, Kevin J., Picazo, Guillermo P.
• Granted Patent: US 6,953,460 B2
• Time in Patent Office: Days
• US Class Current: 601/2
• CPC Class Codes: A61B 18/00 Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body eye surgery A61F9/007; ear surgery A61F11/00
• 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 2017/00243 cardiac
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00148 with metal
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61M 2210/125 Heart
• CPC Class Codes: A61M 25/1002 characterised by balloon shape A61M25/1006, A61M25/1009 take precedence
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: A61N 7/022 intracavitary

Abstract

A tissue ablation catheter for forming a lesion along a substantially circumferential region of tissue is described. The catheter includes one or more sensors for monitoring the temperature of the tissue being ablated. The temperature sensors are mounted on the interior or exterior of an expandable member that is affixed to a shaft of the catheter.

Claims

1. A tissue ablation apparatus for ablating a circumferential region of tissue, comprising:

a guidewire;

an elongate body with a proximal end portion and a distal end portion, the elongate body having a guidewire lumen adapted for slideably receiving the guidewire;

an expandable member coupled to the distal end portion of the elongate body, the expandable member being adjustable from a collapsed position to an expanded position, wherein in the expanded position the expandable member is adapted to engage a substantial portion of the circumferenital region of tissue;

an ultrasound transducer disposed within an interior of the expandable member, the ultrasonic transducer being adapted to emit ultrasound energy for ablating at least a portion of the circumferential region of tissue;

a sensor coupled to the expandable member at a location; and

a conductor coupled to a coupler at the proximal end portion of the elongated body and to the sensor in a manner that does not substantially affect the adjustment of the expandable member from the collapsed position to the expanded position.

2. The apparatus of claim 1, wherein the expandable member comprises an inflatable balloon.

3. The apparatus of claim 1, wherein the sensor is coupled to the expandable member by an adhesive.

4. The apparatus of claim 3, wherein the adhesive encapsulates the sensor.

5. The apparatus of claim 1, wherein the conductor is shaped so as to reduce tension at the location when the expandable member is adjusted between the collapsed position and the expanded position.

6. The apparatus of claim 5, wherein the conductor forms a loop that reduces tension on the location at which the sensor is coupled to the expandable member.

7. The apparatus of claim 5, wherein the conductor forms a helix that reduces tension on the location at which the sensor is coupled to the expandable member.

8. The apparatus of claim 1, wherein the expandable member has an outer surface that is adapted to contact at least the substantial portion of the circumferential region of tissue along an ablative path when the expandable member is adjusted to the expanded position.

9. The apparatus of claim 8, wherein said location is provided along the outer surface.

10. The apparatus of claim 8, wherein the sensor comprises a temperature sensor.

11. The apparatus of claim 10, wherein the location, at which the temperature sensor is coupled to the expandable member, is fixed along the ablative path.

12. The apparatus of claim 8, wherein the sensor comprises an electrode.

13. The apparatus of claim 1, wherein the expandable member has an inner surface and an outer surface, the outer surface being adapted to contact the substantial portion of the circumferenital region of tissue, wherein the location is provided along the inner surface.

14. The apparatus of claim 1, wherein the expandable member further comprises an outer layer and an inner layer, the outer layer comprising an outer surface that is adapted to contact the substantial portion of the circumferential region of tissue, and wherein the sensor is disposed between the outer and inner layers.

15. The apparatus of claim 14, further comprising a passageway between the outer layer and the inner layer, wherein the sensor is slideably engaged within said passageway.

16. The apparatus of claim 15, wherein said passageway is filled with a fluid.

17. The apparatus of claim 1, wherein the location on the expandable member further comprises a reinforcement disposed on an inner surface of the expandable member.

18. The apparatus of claim 1, wherein the location on the expandable member further comprises a reinforcement disposed on an outer surface of the expandable member.

19. The apparatus of claim 1, wherein the conductor further comprises means for reducing tension on said location when the expandable member is adjusted from the collapsed position to the expanded position.

20. The apparatus of claim 1, wherein the expandable member further comprises a passageway and wherein the sensor and the conductor are slideably engaged within the passageway.

21. The apparatus of claim 20, wherein the expandable member has an interior space that is in fluid communication with the passageway.

22. The apparatus of claim 21, wherein the passageway further comprises a stenting member.

23. The apparatus of claim 1, wherein the expandable member comprises a spline.

24. The apparatus of claim 1, wherein the expandable member comprises an inflatable balloon and a spline and wherein the location, at which the sensor is coupled to the inflatable balloon when expanded, is located along the spline.

25. The apparatus of claim 1, wherein the location at which the sensor is coupled to the expandable member is disposed relative to the ultrasound transducer so as to sense a predetermined parameter during ablation.

26. The apparatus of claim 1, wherein the sensor comprises a temperature sensor.

27. The apparatus of claim 1, wherein the sensor comprises an electrode.

28. A method of monitoring the ablation of a selected region of tissue comprising:

providing an ablation member including an ultrasonic transducer disposed within an interior of an expandable member;

positioning the ablation member along the select region of tissue;

emitting ultrasound energy from the ultrasonic transducer to ablate the selected region of tissue;

monitoring a temperature along the selected region of tissue; and

deactivating the ablation element when the temperature along said selected region of tissue has reached either a first predetermined value or a second predetermined valve for a predetermined period of time.

29. The method of claim 28, wherein adjusting the expandable member from the collapsed position to the expanded position further comprises placing a sensor, which is coupled to the expandable member, sufficiently close to the selected region of tissue to allow the sensor to monitor the temperature of the selected region of tissue.