초록 ▼

A pacemaker of the inhibited demand type which is equipped with a battery and pacemaker efficiency evaluator. A magnetically initialized test circuit synchronizes the timing of test stimulating pulses with the natural R-wave or, the end of a basic pacemaker escape interval, thereby to enhance patien

A pacemaker of the inhibited demand type which is equipped with a battery and pacemaker efficiency evaluator. A magnetically initialized test circuit synchronizes the timing of test stimulating pulses with the natural R-wave or, the end of a basic pacemaker escape interval, thereby to enhance patient safety by avoiding competition during testing. The synchronized test circuit produces an alternating sequence of sensing and pacing periods which are maintained during the test. Upon actuation of the test, the first R-wave, or the end of the basic pacer interval, is sensed and a number of stimulating pulses is applied at the end of successive test intervals, which intervals are located between pacemaker output pulses, the duration of which indicates the battery status. This sequence of sensing, synchronization, an application of test pulses is repeated during the duration of the magnet test.

대표청구항 ▼

A method for evaluating the battery status and stimulating effectiveness of an inhibited type cardiac pacemaker system which issues periodic stimulating pulses between basic pacemaker intervals, said pacemaker system including magnet test means for performing said evaluating in a number of magnetic

A method for evaluating the battery status and stimulating effectiveness of an inhibited type cardiac pacemaker system which issues periodic stimulating pulses between basic pacemaker intervals, said pacemaker system including magnet test means for performing said evaluating in a number of magnetic test intervals, means for activating said magnet test means, a synchronizer for coordinating the timing and sensing circuits of the pacemaker system, said system being capable of sensing periodic R-waves of a heart, which method comprises the step of: (a) applying magnetic means to actuate said magnetic test means; (b) sensing one of a first natural R-wave and the end of a first basic pacemaker interval; (c) applying a predetermined number of consecutive asynchronous stimulation pulses, said asynchronous pulses being applied after a magnetic test interval which is shorter in duration than the basic pacemaker interval; (d) sensing one of the next R-waves and end of a basic interval; (e) applying again a sequence of a predetermined number of consecutive asynchronous stimulating pulses during the magnetic test intervals; and (f) repeating steps (a) through (e) for the duration of the magnet test, whereby the length of the magnet interval and the heart response to the stimulating pulses being indicative of battery status and stimulation effectiveness, respectively.