| 摘要 |
<p>Apparatus for stimulating body tissue is disclosed as including a circuit responsive to the initiation of stimulation, failure, or pending failure of a component of the stimulating apparatus, to provide the patient with a perceivable stimulation to a second, different portion of body tissue. An impedance level detector senses the impedance between the outputs of the stimulation apparatus to provide a warning signal indicating that the output impedance falls outside a predetermined range. The impedance level detector output is sensed by a stimulation control logic to apply a first train of pulses at a first rate to an auxiliary electrode for stimulating the second portion of tissue. A voltage level detector senses when the power source voltage depletes below a predetermined level, to actuate the stimulation control logic to provide a second train of warning pulses to the auxiliary electrode, at a second, different rate than that of the first train. The patient is warned as to the pending failure or failure of a component of his pacemaker and is able to identify the failing component. Also provided is decoder logic comprising a switch actuatable by a magnet that may be manipulated exterior of the patient's body to turn off the warning stimulation and/or to reset or reinitialize the operation of the stimulation control logic, so that the stimulation control logic is conditioned to receive further warning signals from either the voltage level detector and/or the impedance level detector.</p> |
