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A cardioverter/defibrillator of the type having at least one high voltage (HV) output capacitor having valve metal anode and cathode electrodes with an oxide formed over a majority of said anode and a wet electrolyte in fluid communication with the electrodes that is charged from a battery through a

A cardioverter/defibrillator of the type having at least one high voltage (HV) output capacitor having valve metal anode and cathode electrodes with an oxide formed over a majority of said anode and a wet electrolyte in fluid communication with the electrodes that is charged from a battery through a charging circuit including a HV step-up transformer and is adapted to be discharged through cardioversion/defibrillation (C/D) electrodes is disclosed. The HV output capacitor(s) periodically charge in a reform charge cycle to substantially a maximum or full charge at a reform charge rate slower than a C/D therapy charge rate, which also charges said HV output capacitor(s) to the maximum or full charge, to thereby reform deformed portions of the oxide.

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What is claimed is: 1. A method of operating a cardioverter/defibrillator of the type having at least one high voltage (HV) output capacitor that comprises a cathode, a valve metal anode with a formed oxide that deforms during periods of electrical inactivity and an electrolyte and that is charged

What is claimed is: 1. A method of operating a cardioverter/defibrillator of the type having at least one high voltage (HV) output capacitor that comprises a cathode, a valve metal anode with a formed oxide that deforms during periods of electrical inactivity and an electrolyte and that is charged from a battery through a charging circuit and is adapted to be discharged through cardioversion/defibrillation (C/D) electrodes comprising: in response to a detected arrthymia, charging at least one HV output capacitor at a therapeutic charging rate substantially to a preprogrammed or maximum charge and either: discharging at least a portion of the charge of said at least one HV output capacitor; or allowing at least a portion of the charge of said at least one HV output capacitor to discharge through a non-therapeutic load; and periodically charging the at least one HV output capacitor at a reform charging rate that is slower than the therapeutic charging rate substantially to the preprogrammed or maximum charge to thereby reform at least a portion of a deformed oxide of said HV output capacitor. 2. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging step of charging and periodically charging both further comprise: delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate. 3. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and wherein the charging and the periodically charging step both further comprise: delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time over the entire reform charge or at least a portion of the reform charge. 4. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging and periodically charging step both further comprise: delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 5. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging and the periodically charging step both further comprise: delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time and the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 6. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging and periodic charging steps both further comprise: delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate. 7. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging and the periodically charging step both further comprise: delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time over the entire reform charge or at least a portion of the reform charge. 8. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging and periodic charging steps further comprise delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 9. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging and periodically charging step further comprise delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time and the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 10. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging steps further comprise delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate. 11. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging steps further comprise delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time over the entire reform charge or at least a portion of the reform charge. 12. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging steps further comprise delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 13. A method according to claim 1, wherein the charging circuit includes a HV step-up transformer and the charging steps further comprise delivering battery energy to a primary winding of the HV step-up transformer during an "on" time to induce a charging current in a secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor, and further comprising: establishing a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and establishing a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time and the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 14. A cardioverter/defibrillator adapted to deliver an electrical cardioversion/defibrillation (C/D) therapy through C/D electrodes in response to a malignant tachyarrhythmia of a heart comprising: a battery; a high voltage (HV) step-up transformer having a primary winding and at least one secondary winding at least one HV output capacitor coupled to the secondary winding, the HV output capacitor comprising a cathode, a valve metal anode having an oxide layer formed on a majority of exposed surfaces of the anode, and a working electrolyte; charging means coupled to the battery and the primary winding and adapted to be operated to charge the HV output capacitor coupled to the secondary winding to a predetermined C/D therapy voltage; first means for establishing a C/D therapy charge rate that determines a C/D therapy charge time; C/D therapy delivery means for operating the charging means at the C/D therapy charge rate to charge the HV output capacitor to the predetermined C/D therapy voltage and for discharging a C/D therapy HV output capacitor through the C/D electrodes; second means for establishing a reform charge rate slower than the C/D therapy charge rate; and capacitor reforming means for operating the charging means at the reform charge rate to charge the HV output capacitor to substantially the predetermined C/D therapy voltage to thereby reform the oxide layer. 15. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; and wherein the first means establishes a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and wherein the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate. 16. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time over the entire reform charge or at least a portion of the reform charge. 17. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 18. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time and a C/D therapy charge "off" time that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time and the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 19. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate. 20. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time over the entire reform charge or at least a portion of the reform charge. 21. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 22. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the charging current induced in the secondary winding that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time and the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 23. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate. 24. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time over the entire reform charge or at least a portion of the reform charge. 25. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 26. A cardioverter/defibrillator according to claim 14, wherein: the charging means further comprises means for applying battery energy to the primary winding of the HV step-up transformer during an "on" time to induce a charging current in the secondary winding coupled with the HV output capacitor during an "off" time that incrementally charges the HV output capacitor; the first means establishes a C/D therapy charge "on" time as a function of battery voltage and a C/D therapy charge "off" time as a function of the HV output capacitor voltage that determines the C/D therapy charge rate; and the second means establishes a reform charge "on" time and a reform charge "off" time that determines the reform charge rate, wherein the reform charge "on" time is shorter than the C/D therapy charge "on" time and the reform charge "off" time is longer than the C/D therapy charge "off" time over the entire reform charge or at least a portion of the reform charge. 27. A cardioverter/defibrillator adapted to deliver a cardioversion/defibrillation (C/D) shock to a patient's heart through C/D electrodes in response to a malignant tachyarrhythmia of the heart comprising: a battery; at least one HV output capacitor comprising a cathode, a valve metal anode having a formed metal oxide dielectric, and an electrolyte; charging means coupled to the battery and the HV output capacitor and adapted to be operated to charge the HV output capacitor to one of a C/D therapy voltage or a capacitor reform voltage to reform the metal oxide dielectric; first means for establishing a C/D therapy charge rate that determines a C/D therapy charge time; C/D therapy delivery means for operating the charging means at the C/D therapy charge rate to charge the HV output capacitor to the C/D therapy voltage and for discharging a C/D therapy HV output capacitor through the C/D electrodes to deliver the C/D shock to the patient's heart; second means for establishing a reform charge rate slower than the C/D therapy charge rate; and capacitor reforming means for operating the charging means at the reform charge rate to charge the HV output capacitor to the reform voltage to reform the metal oxide dielectric. 28. A computer readable medium containing instructions for performing a method of operating a cardioverter/defibrillator of the type having at least one high voltage (HV) output capacitor that comprises a cathode, a valve metal anode with a formed oxide layer that progressively deforms during periods of electrical inactivity and an electrolyte and that is charged from a battery through a charging circuit and is adapted to be discharged through cardioversion/defibrillation (C/D) electrodes comprising: instructions to, in response to a detected arrthymia, charge at least one HV output capacitor at a therapeutic charging rate to a preprogrammed or maximum charge and either discharging at least a portion of the charge of said at least one HV output capacitor or allowing at least a portion of the charge of said at least one HV output capacitor to discharge through a non-therapeutic load; and instructions for periodically charging the at least one HV output capacitor to the preprogrammed or maximum charge at a reform charging rate that is slower than the therapeutic charging rate to thereby reform at least a part of a deformed oxide portion of an oxide layer. 29. A computer readable medium according to claim 28, wherein said instructions for periodically charging the at least one HV output capacitor further comprise: instructions for inhibiting said periodically charging if the instructions to, in response to a detected arrthymia, charge at least one HV output capacitor at a therapeutic charging rate to a preprogrammed or maximum charge were previously performed during a predetermined period of time. 30. A computer readable medium according to claim 29, wherein said predetermined period of time comprises at least a one of: a number of seconds, a number of minutes, a number of hours, a number of weeks, a number of months, a fraction of any of the foregoing. 31. A computer readable medium according to claim 28, wherein said reform charging rate comprises a rate approximately one-half to approximately one-twentieth the therapeutic charging rate. 32. A computer readable medium according to claim 29, wherein said predetermined period of time is either preprogrammed or stored in a computer readable memory storage structure. 33. A computer readable medium according to claim 32, wherein said computer readable memory storage structure comprises a look up table.