Atrial arrhythmia burden on long-term monitoring in asymptomatic patients late after atrial fibrillation ablation

Am J Cardiol. 2012 Sep 15;110(6):840-4. doi: 10.1016/j.amjcard.2012.05.012. Epub 2012 Jun 1.


Patients appearing free of atrial fibrillation (AF) based on limited electrocardiographic monitoring/clinical history late after ablation may still have a large silent AF burden and thus have failed ablations and may be at risk of thromboembolism. We evaluated long-term monitoring (LTM; 7 days or 1 year) in 203 patients off antiarrhythmic drugs who were clinically free of AF >1 year after ablation. A 7-day monitor was done in 186 and 17 had pacemakers in whom the most recent year was analyzed. Arrhythmia recurrence was >30 seconds of AF, flutter, or tachycardia. LTM was done 3.1 ± 1.3 years (range 1.1 to 7.3) after the last ablation. AF recurred in only 8 of 186 (4.3%) on 7-day monitoring. One had persistent AF. For the other 7, AF burden was 0.0075% to 3.34% with 3 of 7 having an AF burden ≤0.037%. AF recurred in 4 of 17 patients (23.5%) with pacemakers. The 4 patients with pacemakers and AF had a 1-year AF burden of 0.0037% to 0.16%. Given the longer duration of monitoring, pacemakers detected more AF than 7-day monitors (p <0.011). AF duration before ablation was the only predictor of AF recurrence on LTM (p = 0.01). In patients with symptomatic AF who appeared free of AF on clinical grounds an average of 3 years after ablation, AF burden on LTM was low. In conclusion, monitoring by implanted devices detects more AF than 7-day monitors, most patients exceeding the failure definition of >30 seconds have a small AF burden, and when using LTM for follow-up the definition of "ablation failure" may be better described by an AF burden >0.5% rather than a single 30-second arrhythmia recurrence.

MeSH terms

  • Arrhythmias, Cardiac / diagnosis*
  • Arrhythmias, Cardiac / physiopathology
  • Atrial Fibrillation / diagnosis*
  • Atrial Fibrillation / physiopathology
  • Atrial Fibrillation / surgery
  • Catheter Ablation*
  • Electrocardiography
  • Female
  • Humans
  • Male
  • Monitoring, Physiologic
  • Recurrence