Clinical utility of intraatrial pacemaker stored electrograms to diagnose atrial fibrillation and flutter

The purpose of this study was to determine if intraatrial electrograms (EGM s) are required to diagnose specific types of atrial tachyarrhythmias detec ted by pacemaker diagnostics. DDD pacemakers in 56 patients were programmed to store episodes of atrial tachyarrhythmias, Some episodes had a stored a trial EGM snapshot of the atrial tachyarrhythmia. The EGMs rt ere analyzed to confirm whether the stored episodes were true atrial tachyarrhythmias or other pacemaker-sensed events. EGM confirmation of atrial tachyarrhythmias correlated with increasing duration and rate of episodes. In particular, u sing EGMs, 8 (18%) of 44 episodes < 10 seconds in duration confirmed atrial tachyarrhythmias compared to 16 (89%) of 18 episodes > 5 minutes in durati on (P < 0.001). Only 10 (18%) of 56 detected atrial arrhythmia episodes at rates < 250 complexes per minute were confirmed by the atrial EGM as true a rrhythmias compared to 33 (57%) of 58 detected episodes at rates > 250/min (P < 0.001) Twenty-nine (91 %) of 32 EGM confirmed episodes of atrial fibri llation/flutter had an atrial rate > 250 complexes per minute and tr ere a minimum of 10 seconds in duration. Fifteen (88%) of 17 episodes meeting the combined stored data criteria of > 250 complexes per minute and duration > 5 minutes were confirmed as atrial fibrillation or flutter by stored EGMs. Atrial EGMs identified that 71 (62%) of 114 stored high atrial rate (HAR) episodes were events other than true atrial tachyarrhythmias. Pacemaker dia gnostic data with intraatrial EGMs can diagnose specific atrial tachyarrhyt hmias and identify other pacemaker-sensed events. Stored episodes > 250 com plexes per minute and > 5 minutes in duration had a high correlation with a trial fibrillation and flutter.