摘要 |
A biphasic cardiac pacer is provided having a novel system for detecting the evoked response from the heart after a stimulating pulse is applied. A relatively short, high absolute amplitude stimulating pulse is applied to the heart. Thereafter, a compensating pulse having an absolute amplitude that is smaller than the absolute amplitude of the stimulating pulse, and having a duration that is longer than the duration of the stimulating pulse, is provided. The stimulating pulse and compensating pulse together comprise a biphasic waveform that provides rapid electrode charge neutralization and enhances subsequent capture detection. The biphasic waveform is automatically and dynamically balanced so that the electrical charge of the stimulating pulse portion is equal to the electrical charge of the compensating pulse portion. After the compensating pulse is provided, the evoked response is detected using the same electrodes that are used for providing the stimulating and compensating pulses.
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