Efficiently delivering acoustic stimulation energy to tissue

• US 9,014,803 B2
• Filed: 12/20/2013
• Issued: 04/21/2015
• Est. Priority Date: 08/01/2005
• Status: Active Grant

• Current Assignee: EBR Systems, Inc.
• Original Assignee: EBR Systems, Inc.
• Inventors: Cowan, Mark A.
• Primary Examiner(s): Bertram, Eric D.
• Application Number:
  US14/136,321
• Publication Number:
  US 20140107725A1
• Time in Patent Office: 487 Days
• Field of Search: 607/33, 607/60, 607/2
• US Class Current: 607/2
• CPC Class Codes: A61N 1/362 Heart stimulators heart defibrillators A61N1/39
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

A system for delivering an electrical stimulation pulse to tissue comprises a controller-transmitter and a receiver-stimulator. The controller-transmitter includes circuitry having an energy storage capacitor. The capacitance of the energy storage capacitor is adjusted to improve the efficiency of energy delivered from the receiver-stimulator to tissue by modifying the geometry of an acoustic drive burst from the controller-transmitter.

Claims

1. A method for driving an implanted acoustically powered receiver-stimulator having at least one tissue-engaging electrode with a tissue-electrode impedance, said method comprising:

directing an acoustic transmission towards the implanted receiver-stimulator, said transmission having an envelope selected to compensate for the tissue-electrode impedance; and

wherein directing the acoustic transmission is generated by supplying voltage to an acoustic transmitter amplifier and controlling the supplied voltage to produce an acoustic transmission having a pre-selected envelope, and wherein the supplied voltage is controlled by selecting the capacitance of an energy storage capacitor in a transmitter voltage power supply circuit.

2. A method as in claim 1, wherein said transmission has a decreasing amplitude.

3. A method as in claim 2, wherein said transmission has an exponentially decreasing amplitude.

4. A method as in claim 2, wherein the amplitude has an initial and final value and the final amplitude of the transmission is from 40% to 60% of the initial amplitude.

5. A method as in claim 1, wherein said envelope is configured with a pre-selected shape.

6. A method as in claim 1, wherein the acoustic transmission is generated by an implanted controller-transmitter.

7. A method as in claim 1, wherein the acoustic transmission is generated by an external controller-transmitter.

9. A method as in claim 1, wherein said envelope is configured with a pre-selected shape.

8. A method for driving an implanted acoustically powered receiver-stimulator having at least one tissue-engaging electrode with a tissue-electrode impedance, said method comprising:

directing an acoustic transmission towards the implanted receiver-stimulator, said transmission having an envelope selected to compensate for the tissue-electrode impedance; and

wherein said transmission has an exponentially decreasing amplitude, wherein the amplitude has an initial and final value and wherein the final amplitude of the transmission is from 40% to 60% of the initial amplitude.

10. A method as in any of claims 8, wherein directing the acoustic transmission is generated by supplying voltage to an acoustic transmitter amplifier and controlling the supplied voltage to produce an acoustic transmission having a pre-selected envelope.

11. A method as in claim 10, wherein the supplied voltage is controlled by selecting the capacitance of an energy storage capacitor in a transmitter voltage power supply circuit.

12. A method as in claim 8, wherein the acoustic transmission is generated by an implanted controller-transmitter.

13. A method as in claim 8, wherein the acoustic transmission is generated by an external controller-transmitter.