| 摘要 |
An apparatus comprises an electrical stimulation circuit, a ventricular sensing circuit, a ventricular sensing timer, and an atrial pacing timer. The ventricular sensing circuit detects an intrinsic ventricular tachyarrhythmia depolarization. The ventricular sensing timer initiates timing of a lowest tachy rate (LTR) zone interval and also a ventricular pace interval that is calculated using a lower rate limit (LRL). The atrial pacing timer calculates an atrial pace interval to follow the intrinsic ventricular depolarization using the ventricular pace interval less a paced atrioventricular (AV) delay interval, delays generation of the atrial pace until after expiration of the LTR zone interval by decreasing the paced AV delay interval when the calculated atrial pace interval is within the LTR zone interval, and disables decreasing of the paced AV delay interval when the LRL interval less the paced AV delay interval at the LRL is less than the LTR zone interval. |
