Patent ID: 6928320

Claim:
A system for producing a desired effect by therapeutically activating tissue at a first predetermined site within a patient's body and for reducing a corresponding undesired side effect by blocking activation of tissue or conduction of action potentials at a second predetermined site within the patient's body, the system comprising: a first signal generator for producing low frequency stimulation; a second signal generator for producing high frequency and/or direct current pulse stimulation; at least one implantable load including a first electrode coupled to the first signal generator, the first electrode being adapted to therapeutically activate tissue at the first predetermined site by applying low frequency stimulation, the at least one implantable lead including a second electrode coupled to the second signal generator, the second electrode being adapted to block activation of electrically excitable tissue at the second site by applying high frequency stimulation or one or more direct current pulses or both high frequency stimulation and one or more direct current pulses at or near the second site; wherein the desired effect is selected from the group consisting of: defibrillation of the patient's atria or defibrillation of the patient's ventricles, and the undesired side effect is pain; and wherein the high frequency stimulation or the direct current pulses or both the high frequency stimulation and the direct current pulses begin before and continue during the therapeutic activation, begin with a relatively low amplitude that is gradually increased, and are terminated by gradually reducing the amplitude of the high frequency stimulation or the direct current pulses or both the high frequency stimulation and the direct current pulses.