| 摘要 |
An implantable dual-chamber pacemaker system has a means for automatic beat-to-beat adjustment of the maximum allowable variation (MAV) of the sensed atrial rate (AR) as a function of the sympatho-vagal balance, switching from an atrial tracking mode of operation (e.g., DDD or DDD(R)) to a non atrial tracking mode (e.g., VDI or VDI(R)) when either an arrhythmic tachycardic rate, exceeding the MAV, or a sinus tachycardic rate, exceeding the maximum tracking atrial rate (MTAR), is detected. The pacemaker provides logic means for continuously determining the atrial rate variation (DELTAAR) and the MAV. The MAV defines the upper limit for the DELTAAR above which tracking is not allowed, discriminating between physiological rate variations and arrhythmic variations. The pacemaker system can return to an atrial tracking mode of operation if the AR remains under a defined rate for a defined number of cycles.
|
