ANODAL EXCITATION OF TISSUE

• US 20100331906A1
• Filed: 06/30/2009
• Published: 12/30/2010
• Est. Priority Date: 06/30/2009
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Williamson, Richard
• Granted Patent: US 8,126,546 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence

Abstract

A cardiac stimulation device has a plurality of electrodes that deliver therapeutic electrical stimulation to the heart. At least one electrode is designated a cathode that cathodically induces depolarization of the surrounding heart tissue. At least one electrode is designated an anode. The device is configured, through one or more of electrode size, electrode configuration, electrode arrangement, cathode/anode number and pulse delivery circuitry, to induce depolarization of the heart tissue in the area of the at least one anode electrode, thereby resulting in greater depolarization of the heart tissue with reduced power consumption.

Claims

1. An implantable cardiac stimulation device comprising:

at least one lead adapted to be implanted adjacent the tissue of a heart, wherein the at least one lead defines a plurality of electrodes wherein at least one of the plurality of electrodes is designated a cathode and at least one of the plurality of electrodes is designated an anode; and

a controller that receives signals indicative of the heart function, wherein the controller induces the delivery of electrical stimulus to the heart via the cathode so as to induce depolarization of the heart tissue adjacent the cathode and to induce depolarization of the heart tissue adjacent the anode in response to the cathodically induced depolarization of heart tissue.

2. The device of claim 1, wherein the anode induces depolarization of the heart tissue as a result of make break effects, an electrically balancing repolarization signal applied to the anode electrode or some combination thereof.

3. The device of claim 1, wherein the at least one lead comprises a plurality of leads that are adapted to provide pacing stimulus to the heart.

4. The device of claim 3, wherein the plurality of leads includes a right ventricular lead and a left ventricular lead each having a tip electrode and wherein the right ventricular tip electrode comprises the cathode and the left ventricular tip electrode comprises the anode.

5. The device of claim 3, wherein the plurality of leads includes a right ventricular lead and at least one left ventricular lead, wherein the left ventricular lead includes a plurality of spaced electrodes and wherein one of the plurality of spaced ring electrodes comprises the anode.

6. The device of claim 5, wherein an electrode on the right ventricular lead and at least one electrode on the left ventricular lead comprises the cathode and wherein another one of the electrodes on the left ventricular lead comprises the anode.

7. The device of claim 1 wherein at least one additional electrode is designated a cathode such that the number of cathode electrodes is greater than the number of anode electrodes.

8. The device of claim 1, wherein the controller actively induces repolarization of the heart tissue at the cathode so as to induce higher current density at the anode to thereby induce anodal stimulation of the heart tissue adjacent the anode.

9. The device of claim 8, wherein the controller provides a pacing pulse of approximately 0.5 ms in duration to induce depolarization of the heart tissue adjacent the cathode and wherein the controller provides a repolarization signal of a duration of approximately 0.5 ms to induce repolarization at the cathode and to induce depolarization at the anode.

10. The device of claim 8, wherein the device includes a plurality of controlled switches allowing the controller to deliver a cathodal pulse for a desired time frame and further allowing the controller to deliver an anodal pulse for a desired time frame.

11. The device of claim 10, wherein the device includes a measurement device for determining the amount of energy that has been delivered via the anode to thereby allow the controller to control the amount of energy being delivered via the anode.

12. The device of claim 11, wherein the measurement device includes either a capacitor or a resistor that is sampled by a voltage controlled oscillator (VCO) and a counter.

13. An implantable cardiac stimulation device comprising:

a plurality of leads that are adapted to be positioned within the chambers of a patient'"'"'s heart so as to deliver therapeutic electrical stimuli thereto, wherein each of the plurality of leads includes a plurality of electrodes adapted to deliver the electrical stimuli so as to induce depolarization of heart tissue adjacent the plurality of electrodes; and

a controller that induces the delivery of therapeutic electrical stimuli via at least one of the electrodes on the plurality of leads that is designated a cathode so as to cathodically induce depolarization of heart tissue adjacent the at least one electrode designated the cathode and wherein the delivery of therapeutic electrical stimuli via the at least one electrode results in anodally induced depolarization of heart tissue adjacent at least one electrode designated by the controller as an anode.

14. The device of claim 13, wherein the anode induces depolarization of the heart tissue as a result of one or both of make break effects, and an electrically balancing repolarization signal applied to the anode electrode.

15. A method of delivering therapeutic electrical stimuli to the heart of a patient, the method comprising:

implanting at least one lead having a plurality of electrodes adjacent the heart of the patient;

designating at least one of the plurality of electrodes to be the cathode and at least one of the plurality of electrodes to be the anode; and

delivering therapeutic electrical stimulation from the cathode so as to induce depolarization of the heart tissue adjacent the cathode and wherein the delivery of electrical stimulation from the cathode results in depolarization of the heart tissue adjacent the anode.

16. The method of claim 15, wherein the depolarization of the heart tissue adjacent the anode is the result of make break effects, the electrically balancing repolarization signal of the anode or some combination thereof.

17. The method of claim 15, wherein designating at least one of the plurality of electrodes to be the cathode comprises designating a plurality of electrodes to be the cathode and wherein designating at least one electrode to be the anode comprises designating a single electrode to be the anode to thereby receive enhanced current density as a result of receiving signals from each of the plurality of cathodes.

18. The method of claim 15, wherein implanting at least one lead comprises implanting a plurality of pacing leads within both the right ventricle and the left ventricle of the heart and wherein delivering therapeutic electrical stimulation to the heart comprises delivering pacing pulses to the heart to thereby provide cardiac resynchronization therapy.

19. The method of claim 15, further inducing repolarization of the heart tissue at the cathode so as to induce higher current density at the anode to thereby induce anodal stimulation of the heart tissue adjacent the anode.

20. The method of claim 19, wherein repolarization of the heart tissue at the cathode so as to induce higher current density at the anode comprises delivering a repolarization signal to the cathode of opposite polarity as the electrical stimuli following delivery of the electrical stimuli.