摘要 |
<p>A heart rate detector apparatus, particularly for use in an implantable defibrillator. The heart rate detector apparatus includes two distinct detector circuits (4, 6) each responsive to ECG waveforms (2) of different characteristics. One of the detector circuits (4) is responsive to ECG waves having slew rates above a predetermined threshold. The other detector circuit (6) is responsive to ECG waves of more sinusoidal shape. A coupling circuit (10) automatically couples one of the two detector circuits (4, 6) to an output circuit, (12) such as a heart rate comparator (86). In a specific embodiment, the heart rate comparator determines the heart rate, compares the heart rate with a predetermined rate (90), and, if the heart rate exceeds the predetermined rate for a predetermined time period (93), provides an output signal (100). The output signal may be used to enable a defibrillating circuit to deliver a defibrillating shock to the patient.</p> |