| 摘要 |
In an apparatus for terminating atrial fibrillation using pulses having an energy content which is the same as the energy content of conventional pacing pulses, stimulation pulses are respectively emitted by a number of electrodes disposed at different sites in or on a heart experiencing atrial fibrillation. When atrial fibrillation is detected, waveforms are measured at each of the electrodes, and the electrode having the waveform exhibiting the shortest interval between successive identifiable, cyclical waveform characteristics, such as successive P-waves, is selected as a first electrode for beginning an atrial defibrillation attempt. Stimulation pulses are emitted from the first electrode at a stimulation rate which is slightly shorter than the aforementioned shortest interval and the other electrodes are stimulated at a rate which is slightly shorter than the rate for the first electrode. All of the stimulation pulses are delivered starting at the latest local detection point in time. Upon each of the other electrodes reaching a point at which emits a stimulation pulse which coincides with a stimulation pulse emitted by the first electrode, that other electrode is locked to the stimulation rate of the first electrode, until all of the electrodes are stimulating at a coincident rate. Detection is periodically undertaken to determine whether atrial fibrillation has been terminated, and if so the pacemaker resumes its normal pacing operation. If the atrial fibrillation has not been terminated, the procedure is continued (if not yet ended) or repeated. <IMAGE>
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