Abstract: The present invention outlines structures and methods for delivering a controllable amount of energy to a patient by automatically compensating for the load impedance detected by an implantable-cardioverter defibrillator (ICD). The invention employs high speed, switching power converter technology for the efficient generation of high energy, arbitrarywaveforms. Unlike a linear amplifier, switching power converters deliver high-energy waveforms with an efficiency that is independent of the size and amplitude of the desired waveform. An ICD that uses a switching power converter to deliver the desired energy to the patient stores the energy to be delivered in a storage capacitor. The converter then transforms this energy into an arbitrarily shaped output voltage-controlled or current-controlled waveform by switching the storage capacitor in and out of the output circuit at a high rate of speed. Preferably, the waveform comprises a ramp-type waveform.

Abstract: The present invention outlines structures and methods for delivering a controllable amount of energy to a patient by automatically compensating for the load impedance detected by an implantable-cardioverter defibrillator (ICD). The invention employs high speed, switching power converter technology for the efficient generation of high energy, arbitrary waveforms. Unlike a linear amplifier, switching power converters deliver high-energy waveforms with an efficiency that is independent of the size and amplitude of the desired waveform. An ICD that uses a switching power converter to deliver the desired energy to the patient stores the energy to be delivered in a storage capacitor. The converter then transforms this energy into an arbitrarily shaped output voltage-controlled or current-controlled waveform by switching the storage capacitor in and out of the output circuit at a high rate of speed. Preferably, the waveform comprises a ramp-type waveform.

Abstract: Primarily, the invention relates to a safe delivery of atrial cardioversion pulses in complex cardiac therapy environments wherein cardiac events suggest, for example, rapid ventricular rates that would prevent a safe atrial cardioversion. The invention generally utilizes an algorithmic system in which a resultant R-R interval encountered subsequent to the delivery of a ventricular pacing pulse is decrementally scanned until an R-R interval is found that will yield a reliable sustained R-R interval. The sustenance of the R-R interval prolongation enables ventricular deceleration. Strategically selected timing windows are used to trigger a device response that is proper and tailored to the ventricular event detected during and within the timing windows. Further, the invention enables an atrial cardioversion synchronization method that allows for the safe delivery of atrial cardioversion pulses in the presence of very rapid ventricular rates.

Abstract: The present invention outlines structures and methods for delivering a controllable amount of energy to a patient by automatically compensating for the load impedance detected by an implantable-cardioverter defibrillator (ICD). The invention employs high speed, switching power converter technology for the efficient generation of high energy, arbitrary waveforms. Unlike a linear amplifier, switching power converters deliver high-energy waveforms with an efficiency that is independent of the size and amplitude of the desired waveform. An ICD that uses a switching power converter to deliver the desired energy to the patient stores the energy to be delivered in a storage capacitor. The converter then transforms this energy into an arbitrarily shaped output voltage-controlled or current-controlled waveform by switching the storage capacitor in and out of the output circuit at a high rate of speed. Preferably, the waveform comprises a ramp-type waveform.