Clinical testing of a dual chamber atrial tachyarrhythmia detection algorithm

Currently available implantable cardioverter-defibrillators (ICDs) treat ventricular tachyarrhythmias and bradyarrhythmias (VVI), and do not intentionally treat atrial tachyarrhythmias. The Medtronic AMD 7250 dual chamber ICD combines detection and therapy for atrial and ventricular tachyarrhythmias. The dual chamber sensing/pacing circuits and tachyarrhythmia detection algorithms in an external prototype of the AMD 7250 have been studied during human cardiac electrophysiologic (EP) studies and ICD implants at Mayo Clinic. No adverse interactions between sensing, pacing and tachyarrhythmia detection were observed. Atrial tachyarrhythmia detection was appropriate in 12/12 episodes of induced atrial fibrillation, 19/20 episodes of induced atrial flutter; and 6/9 episodes of induced atrial tachycardia. Overall detection performance for non-1:1 atrial tachyarrhythmias was 97% (37/38 episodes).