AIMS: Early recurrences (ER) of atrial arrhythmias are common after catheter ablation of atrial fibrillation (AF). The significance of these ER is controversial.
Based on data of continuous cardiac monitoring, we sought to investigate the characteristics of ER and their impact on late recurrences (LR) during follow-up.
METHODS: One hundred twenty-six patients with paroxysmal (49%) or persistent (51%) AF underwent an AF ablation with subsequent implantation of implantable loop recorder. Follow up was 12 months using remote monitoring. All atrial arrhythmia (AF or atrial tachycardia-AT-) episodes >30 seconds. within the 3-month blanking period were considered and the AF burden evaluated every 3 months.
RESULTS: Within the 3-months blanking period, 72 patients (57%) experienced an AF/AT recurrence. Survival free from any arrhythmia recurrence during follow-up was 40% in patients with ER vs 69% in those without ER. AF burden during the blanking period and timing of ER correlated significantly with LR at 12 months (area under curve = 0.74, P < .0001 and .831, P < .0001). An AF burden ≥0.5% and ER after 74 days predicted LR (sensitivity 60%, specificity 84.4%; sensitivity 75.6%, specificity 90.3%). In cox regression analysis, AF burden ≥0.5% and ER after 74 days were independently associated with LR.
CONCLUSIONS: Continuous cardiac monitoring after AF ablation provides important information regarding early recurrence episodes and their prognostic impact. A cut-off of 74 days for the blanking period seems to better differentiate patients with a good or a poor long-term outcome. An AF burden ≥0.5% during the 3 months postablation is predictive for late arrhythmia recurrences.