Rate responsive dual chamber pacing.

We report about a new pacemaker, which simultaneously offers dual chamber pacing in DDD Mode and activity controlled rate response. The system also uses activity-sensing to differentiate true sinus tachycardia from ectopic atrial activity or atrial fibrillation and therefore prevents pacemaker mediated arrhythmias. The clinical experience proves appropriate functioning of all technical aspects of the device. Preliminary noninvasive hemodynamic assessments confirm improvement in cardiac function with AV synchronous pacing mode and demonstrate the ouporiority of rate-responsive dual chamber versus single ventricular pacing.