IMPLANTABLE MEDICAL DEVICES WITH PIEZOELECTRIC ANCHORING MEMBER

• US 20100317929A1
• Filed: 05/06/2010
• Published: 12/16/2010
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation), Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Juffer, Lance E., Piaget, Thomas W., Chavan, Abhijeet V., Maile, Keith R., Mi, Bin
• Granted Patent: US 8,506,495 B2
• Time in Patent Office: Days
• US Class Current: 600/300
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61N 1/36564 controlled by blood pressure
• CPC Class Codes: A61N 1/37205 Microstimulators, e.g. implantable through a cannula
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37288 Communication to several implantable medical devices within one patient
• CPC Class Codes: A61N 1/375 Constructional arrangements, e.g. casings
• CPC Class Codes: A61N 1/37512 Pacemakers
• CPC Class Codes: A61N 1/37516 Intravascular implants
• CPC Class Codes: A61N 1/37518 Anchoring of the implants, e.g. fixation

Abstract

Methods, systems, and apparatus for powering and/or recharging medical devices implanted within the body are described. An illustrative implantable medical device includes a housing having an internal cavity and a flexible anchor assembly that is coupled to the housing. The flexible anchor assembly includes a first electrical conductor, a second electrical conductor, and a piezoelectric layer that is disposed between the first and second electrical conductors and that is configured to displace in response to a physiologic force applied to the flexible anchor assembly and generate a voltage differential between the first and second electrical conductors. The implantable medical device includes power circuitry that converts the voltage differential between the first and second electrical conductors into an operating current for powering one or more components within the implantable medical device and/or for recharging a rechargeable power supply within the device.

Claims

1. An implantable medical device, comprising:

a housing including an internal cavity;

a flexible anchor assembly coupled to the housing, the flexible anchor assembly including a first electrical conductor, a second electrical conductor, and a piezoelectric layer disposed between the first and second electrical conductors, the piezoelectric layer configured to displace in response to a physiologic force applied to the flexible anchor assembly and generate a voltage differential between the first and second electrical conductors; and

power circuitry configured to convert the voltage differential between the first and second electrical conductors into an operating current for powering one or more components of the implantable medical device.

2. The implantable medical device of claim 1, further comprising a sensor module disposed within the interior cavity of the housing, the sensor module configured to sense one or more physiologic parameters within a body lumen.

3. The implantable medical device of claim 2, wherein the flexible anchor assembly is configured to secure the implantable medical device within the body lumen.

4. The implantable medical device of claim 2, wherein at least a portion of the flexible anchor assembly is configured to displace in response to periodic pressure pulses within the body lumen.

5. The implantable medical device of claim 1, wherein the flexible anchor assembly is configured to be helically wound within a blood vessel such that at least a portion of the flexible anchor assembly displaces in response to periodic vessel diameter fluctuations.

6. The implantable medical device of claim 1, wherein the flexible anchor assembly further comprises a tissue attachment structure disposed at an end of the flexible anchor assembly opposite an end coupled to the housing, the tissue attachment structure configured for attachment to a structure within a patient.

7. The implantable medical device of claim 6, wherein displacement of the housing in response to physiologic forces cause the piezoelectric layer to displace and generate a voltage differential between the first and second electrical conductors.

8. The implantable medical device of claim 1, further comprising a wireless communication module disposed within the internal cavity.

9. The implantable medical device of claim 1, further comprising a rechargeable power supply disposed within the internal cavity.

10. The implantable medical device of claim 1, wherein the flexible anchor assembly comprises a helical structure including:

a helical piezoelectric ribbon having a first surface and an opposing second surface;

the first electrical conductor disposed in contact with the first surface of the helical piezoelectric ribbon; and

the second electrical conductor disposed in contact with the second surface of the helical piezoelectric ribbon.

11. An implantable sensor for sensing one or more physiologic parameters within a body lumen, comprising:

a housing including an exterior housing wall having an inner surface and an outer surface, the exterior housing wall defining an internal cavity;

a sensor module disposed within the interior cavity of the housing, the sensor module configured to sense one or more physiologic parameters within the body lumen;

a flexible anchor assembly coupled to the housing, the flexible anchor assembly including a first electrical conductor, a second electrical conductor, and a piezoelectric layer disposed between the first and second electrical conductors, the piezoelectric layer configured to displace in response to periodic pressure pulses within the body lumen and generate a voltage differential between the first and second electrical conductors; and

power circuitry configured to convert the voltage differential between the first and second conductors into an operating current for powering one or more components of the implantable sensor.

12. The implantable sensor of claim 11, wherein the one or more components includes a rechargeable power supply.

13. The implantable sensor of claim 11, wherein the flexible anchor assembly contacts an inner surface of the body lumen to anchor the implantable sensor within the body lumen.

14. A method of generating electrical power within the body of a patient, the method comprising:

inserting an implantable medical device into the body, the implantable medical device including;

a housing including an exterior housing wall having an inner surface and an outer surface, the exterior housing wall defining an internal cavity;

a flexible anchor assembly coupled to the housing, the flexible anchor assembly including a first electrical conductor, a second electrical conductor, and a piezoelectric layer disposed between the first and second electrical conductors, the piezoelectric layer configured to displace in response to a bodily force applied to the implantable medical device and generate a voltage differential between the first and second electrical conductors; and

power circuitry configured to convert the voltage differential between the first and second conductors into an operating current for powering one or more components of the implantable medical device;

operating the implantable medical device within the body at a location that subjects the piezoelectric layer to a bodily force, causing a voltage differential between the first and second electrical conductors; and

converting the voltage differential into an operating current for powering one or more components of the implantable medical device.

15. The method of claim 14, wherein inserting the implantable medical device within a patient comprises inserting the implantable medical device into a body lumen such that the implantable medical device will be exposed to periodic pressure pulses within the body lumen.

16. The method of claim 15, wherein at least a portion of the flexible anchor assembly is configured to contact an interior portion of the body lumen to anchor the implantable medical device within the body lumen.

17. The method of claim 14, wherein the one or more components includes a rechargeable power source, the method further comprising charging the rechargeable power source with the operating current.

18. The method of claim 14, wherein the one or more components includes sensing circuitry, the method further comprising using the operating current to power the sensing circuitry.

19. The method of claim 14, wherein the one or more components includes wireless communication circuitry, the method further comprising using the operating current to power the wireless communication circuitry.

20. The method of claim 14, wherein the flexible anchor assembly further comprises a tissue attachment structure disposed at an end of the flexible anchor assembly opposite an end coupled to the housing, and the method further comprises attaching the tissue attachment structure to a structure within a patient.

21. The method of claim 14, wherein the flexible anchor assembly comprises a helical structure wherein:

the piezoelectric layer includes a piezoelectric ribbon having a first surface and an opposing second surface;

the first electrical conductor contacts the first surface of the piezoelectric ribbon; and

the second electrical conductor contacts the second surface of the piezoelectric ribbon.