Patent 4066086 Issued on January 3, 1978. Estimated Expiration Date: January 3, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A body implantable device for providing electrical stimulation to living animal tissue. The device includes a pulse generator having at least one alterable output parameter and circuitry responsive to first externally generated signals for altering the alterable output parameter in predetermined correspondence with the number of said first signals. The output parameter altering circuitry is enabled only during the occurrence of second signals having characteristics discriminable from the characteristics of the first signals. In a preferred embodiment, the first signals are pulses of radio frequency energy and the second signals are magnetic. The invention may be embodied in a cardiac pacemaker of either the asynchronous or demand type and the second signals may be employed to cause a demand cardiac pacemaker to revert to an asynchronous operation.