Implantable cardiac defibrillation system with defibrillation electrode entrapment prevention and method

• US 8,170,689 B2
• Filed: 07/17/2007
• Issued: 05/01/2012
• Est. Priority Date: 03/05/2004
• Status: Active Grant

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Inventors: Kroll, Mark W., Mouchawar, Gabriel A., Moulder, J. Christopher
• Primary Examiner(s): KAHELIN, MICHAEL WILLIAM
• Application Number:
  US11/779,158
• Publication Number:
  US 20080015646A1
• Time in Patent Office: 1,750 Days
• Field of Search: 607/121
• US Class Current: 607/121
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: A61N 1/39622 Pacing therapy
• CPC Class Codes: A61N 1/3975 Power supply A61N1/378 takes precedence

Abstract

An implantable cardiac defibrillation device diminishes fibrosis of a defibrillation electrode. The device includes an implantable lead having a defibrillation electrode adapted for implant in one of the superior vena cava and right ventricle of a heart, a pulse generator adapted to be coupled to the defibrillation electrode that provides defibrillation energy to the defibrillation electrode, and a power supply that maintains a negative voltage on the defibrillation electrode in the absence of defibrillating energy being provided to the defibrillation electrode.

Claims

1. An implantable cardiac defibrillation system comprising:

an implantable defibrillation lead having a defibrillation shock coil;

a pulse generator adapted to be coupled to the defibrillation shock coil for delivery of defibrillation shocks; and

a power supply that is electrically coupled to the shock coil for a first period of time to maintain a negative voltage on the defibrillation shock coil for the first period of time and is electrically decoupled from the shock coil for a second period of time wherein the first period of time is longer than the second period of time.

2. The device of claim 1, wherein the pulse generator includes an electronic switching device which, when closed, delivers defibrillating energy to the defibrillation shock coil and wherein the power supply includes a current path that conducts leakage current across the switch when the switch is open to maintain the negative voltage on the defibrillation shock coil.

3. The device of claim 2, wherein the power supply includes a diode coupled to the switch and a current source that back biases the diode to cause the leakage current.

4. The device of claim 3, wherein the current path comprises a resistor coupled across the switch.

5. The device of claim 3, wherein the current source comprises a current regulator.

6. The device of claim 1, wherein the negative voltage has an absolute value on the order of 125 mV or greater.

7. The device of claim 1, wherein the defibrillation electrode is configured for implant in the superior vena cava.

8. The device of claim 1, wherein the defibrillation electrode is configured for implant in the right atrium.

9. The device of claim 1 wherein the defibrillation electrode is configured for implant in the right ventricle.

10. An implantable cardiac defibrillation system comprising:

an implantable lead having a defibrillation shock coil adapted for implant in one of the superior vena cava and right ventricle of a heart;

a pulse generator adapted to be coupled to the defibrillation shock coil that provides defibrillation energy to the defibrillation electrode; and

a power supply that is electrically coupled to the shock coil for a first period of time to maintain a negative voltage on the defibrillation shock coil for the first period of time and wherein is electrically decoupled from the shock coil for a second period of time wherein the first period of time is longer than the second period of time.

11. The device of claim 10, wherein the pulse generator includes an electronic switching device which, when closed, provides the defibrillating energy to the defibrillation shock coil and wherein the power supply includes a current path that conducts leakage current across the switch when the switch is open to maintain the negative voltage on the defibrillation shock coil.

12. The device of claim 11, wherein the power supply includes a diode coupled to the switch and a current source that back biases the diode to cause the leakage current to be conducted.

13. The device of claim 12, wherein the current path comprises a resistor coupled across the switch.

14. The device of claim 12, wherein the current source comprises a current regulator.

15. The device of claim 10, wherein the negative voltage is on the order of 175 mV.

16. The device of claim 10, wherein the defibrillation electrode is configured for implant in the superior vena cava.

17. The device of claim 10, wherein the defibrillation electrode is configured for implant in the right ventricle.