LEADLESS INTRA-CARDIAC MEDICAL DEVICE WITH INTEGRATED L-C RESONANT CIRCUIT PRESSURE SENSOR

• US 20140100627A1
• Filed: 10/08/2012
• Published: 04/10/2014
• Est. Priority Date: 10/08/2012
• Status: Abandoned Application

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Min, Xiaoyi
• Application Number:
  US13/647,300
• Publication Number:
  US 20140100627A1
• Time in Patent Office: Days
• US Class Current: 607/32
• CPC Class Codes: A61B 5/02158 provided with two or more sensor elements
• 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 1/3727 characterised by the modulation technique
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

A leadless intra-cardiac medical device comprises an integrated L-C resonant circuit pressure sensor. In some embodiments, the pressure sensor comprises a passive sensor that measures pressure in response to an externally generated excitation signal. In some embodiments, the pressure sensor comprises an active sensor that measures pressure in response to an internally generated excitation signal.

Claims

1. A leadless intra-cardiac medical device, comprising:

a housing comprising an exterior surface and defining an interior space;

an inductor-capacitor resonant circuit located within the interior space defined by the housing, wherein the inductor-capacitor circuit comprises an inductive circuit and a flexible capacitive circuit electrically coupled in parallel;

a flexible material located adjacent the exterior surface of the housing and engaged with the flexible capacitive circuit to couple pressure waves to the flexible capacitive circuit;

at least one electrode located adjacent the exterior surface of the housing; and

a circuit located within the interior space defined by the housing and electrically coupled to the inductor-capacitor resonant circuit and to the at least one electrode, wherein the circuit is configured to;

process signals received from the inductor-capacitor resonant circuit to generate data representative of the pressure waves,

generate cardiac stimulation pulses for application via the at least one electrode based on control information, and

communicate via radiofrequency signaling with an external device to send the data to the external device and to receive the control information from the external device.

2. The device of claim 1, wherein the processing of the signals received from the inductor-capacitor resonant circuit to generate the data comprises:

processing the received signals to determine at least one frequency of the signals; and

determining at least one pressure value based on the determined at least one frequency, wherein the generated data comprises the determined at least one pressure value.

3. The device of claim 1, wherein the circuit is further configured to:

receive a message via radiofrequency signaling; and

commence the generation of the data as a result of the receipt of the message.

4. The device of claim 3, wherein:

the device further comprises a battery circuit;

the inductor-capacitor resonant circuit further comprises an excitation circuit electrically coupled to receive power from the battery circuit and configured to excite the inductor-capacitor resonant circuit by generating an excitation signal; and

the circuit is further configured to trigger excitation of the inductor-capacitor resonant circuit by the excitation circuit as a result of the receipt of the message.

5. The device of claim 4, wherein the circuit is further configured to receive damping signals from the inductor-capacitor resonant circuit as a result of the receipt of the message.

6. The device of claim 4, wherein the excitation circuit comprises an oscillator circuit coupled to receive power from the battery circuit.

7. The device of claim 4, wherein the excitation signal comprises at least one pulse signal or the excitation signal comprises a modulated oscillating signal having a center frequency approximately equal to a resonant frequency of the inductor-capacitor resonant circuit.

8. The device of claim 1, wherein the flexible material comprises an insulating material.

9. The device of claim 1, wherein the circuit is further configured to:

receive a signal via radiofrequency signaling; and

commence the generation of the data as a result of the receipt of the signal via radiofrequency signaling.

11. The device of claim 1, wherein:

the processing of the signals received from the inductor-capacitor resonant circuit to generate the data comprises;

processing the received signals to determine at least one frequency of the signals, and determining at least one pressure value based on the determined at least one frequency, wherein the generated data comprises the determined at least one pressure value;

the circuit is further configured to receive a message via radiofrequency signaling and commence the generation of the data as a result of the receipt of the message;

the device further comprises a battery circuit;

the inductor-capacitor resonant circuit comprises an excitation circuit electrically coupled to receive power from the battery circuit and configured to excite the inductor-capacitor resonant circuit by generating an excitation signal; and

the circuit is further configured to trigger excitation of the inductor-capacitor resonant circuit by the excitation circuit as a result of the receipt of the message.

12. The device of claim 11, wherein the excitation circuit comprises an oscillator circuit coupled to receive power from the battery circuit.

13. The device of claim 1, wherein:

the processing of the signals received from the inductor-capacitor resonant circuit to generate the data comprises;

processing the received signals to determine at least one frequency of the signals, and determining at least one pressure value based on the determined at least one frequency, wherein the generated data comprises the determined at least one pressure value; and

the circuit is further configured to receive a signal via radiofrequency signaling and commence the generation of the data as a result of the receipt of the signal via radiofrequency signaling.

14. The device of claim 1, wherein:

the device further comprises a battery located within the interior space defined by the housing; and

wherein the flexible capacitive circuit includes a cylindrical plate and wherein at least a portion of the cylindrical plate of the flexible capacitive circuit circumscribes at least a portion of the battery.

15. The device of claim 14, wherein the housing is hermetically sealed.

16. The device of claim 1, wherein a resonant frequency of the inductor-capacitor resonant circuit is less than 10 MHz.

17. The device of claim 1, wherein the flexible capacitive circuit includes a cylindrical plate and wherein a diameter of the cylindrical plate of the flexible capacitive circuit is greater than 7 french.

18. The device of claim 1, wherein the inductive circuit includes a coil and wherein a diameter of a coil of the inductive circuit is greater than 7 french.

10. (canceled)

19. A pressure sensing method, comprising:

triggering an excitation circuit of a leadless intra-cardiac medical device to excite an inductor-capacitor resonant circuit of the leadless intra-cardiac medical device, wherein a flexible material located adjacent an exterior surface of a housing is engaged with a capacitive circuit of the inductor-capacitor resonant circuit to couple pressure waves to the capacitive circuit;

processing signals produced by the excited inductor-capacitor resonant circuit to determine at least one frequency of the signals;

generating data representative of pressure external to the leadless intra-cardiac medical device based on the determined at least one frequency; and

transmitting the generated data via radiofrequency signaling to an external device.

20. The method of claim 19, further comprising:

receiving a message via radiofrequency signaling; and

commencing the generation of the data as a result of the receipt of the message.

21. The method of claim 20, wherein the triggering of the excitation circuit is based on the receipt of the message.