In an implanted pacemaker three basic pacing intervals are established: an A-V delay, a PVARP and an alert interval. These three intervals together define an atrial-to atrial interval which is preferably a function of a metabolic indicated rate. The PVARP and alert interval are adaptively adjusted to...http://www.google.de/patents/US5609610?utm_source=gb-gplus-sharePatent US5609610 - Dual chamber pacemaker with automatic adaptation for intrinsic atrial events
