摘要 |
An automatic fibrillator for inclusion in an implantable defibrillator. Fibrillation induction takes place while the patient's heart is beating at a known rate, and the fibrillation inducing pulse is delivered at a time based on the expected or measured natural refractory period of the patient's heart, at the heart rate in effect during fibrillation induction. In its preferred embodiment, fibrillation induction takes place during overdrive pacing, and the timing of the pulse takes place using an overdrive pacing pulse as a time reference. The period between the pacing pulse and the fibrillation inducing pulse may be determined as a function of actual measurement of the patient's refractory period, either directory, or by means of measurement of the Q-T interval of the patient's heart. |