Abstract 3261: Characterization of Onset Scenarios of Paroxysmal Atrial Fibrillation in Patients without Pacemaker Indication
Atrial-based pacing has recently gained prominence as a new concept for prevention of paroxysmal atrial fibrillation (pAF) by suppressing atrial ectopy and eliminating bradycardia. Data on type and frequency of heart rate and rhythm changes preceding pAF are thus far only available from smaller studies investigating pAF onset from pacemaker memory. However, potential triggers for pAF have not yet been systematically characterized in a large patient population without pacemaker indication.
Methods and Results: From a total of 20.546 consecutive ambulatory 3-channel-24-hour-Holter-ECG-recordings, 715 episodes of pAF were identified in 350 patients [191 male, 159 female; 70.5± 11 (27–97) years]. The dominant portion of pAF onsets were preceded without rate or rhythm changes (sudden onset, n=276; 38.6%), followed by atrial premature beat-(APB) related episodes [multiple APB, n=134 (18.7%); short atrial runs; n=43 (6.0%); single APB, n=36 (5.0%); short-long-short sequence, n=17 (2.4%); blocked APB, n=2 (0.3%)]. Ventricular premature beats (VPB) were seen before pAF in 9.4% (n=67), heart rate related onset scenarios in 24.3% (n=140) [bradycardia, n=97 (13.6%); tachycardia, n=34 (4.8%); sudden rate drop, n=9 (1.3%)]. There were no gender related differences regarding onset scenarios before pAF (Fig. 1⇓.).
Connclusion: In this study providing detailed analysis of spontaneous pAF, the overall distribution of pAF onset scenarios is similar in male and female subjects. The majority of pAF onset scenarios is not preceded by triggering factors or heart rate changes, giving no potential target for pAF prevention by atrial-based pacing strategies in this patient population.