Properly quantifiying outcomes of AF Ablation - Is a 30-second
recurrence an evidence-based endpoint?
Background: Although atrial fibrillation (AF) ablation is a
well-established treatment, the classical definition of recurrence and
therefore success is not evidence-based. Additionally, the frequency of
asymptomatic patients whose episodes are not noticed on routine
electrocardiogram (ECG) may compromise the actual success rate.
Objectives: This study aimed to assess the characteristics of AF burden
after atrial fibrillation ablation and its influence on patients’
symptoms in the setting of continuous remote monitoring. It also sought
to investigate a relevant cutoff as a new definition for recurrence.
Methods: 141 consecutive patients with symptomatic paroxysmal or
persistent AF underwent an AF ablation and then were followed by
continuous rhythm monitoring. The AF/atrial tachycardia (AT) burden,
duration of episodes and symptoms where registered systematically.
Results: After the blanking period, freedom from AF/AT
>30sec. was 59%. Considering an AF-Burden <1%,
the success rate was 80%. The incidence of asymptomatic episodes in the
group of patients with conventional recurrence was 24% (14/58) and 20%
(8/41) when a cut-off of 1% of AF/AT burden was considered.
Asymptomatic patients had an AF burden of 1.87 ± 4.6% during follow-up,
compared to 4.0 ± 7.2% in symptomatic patients (p=0.02). There was no
statistical difference between AF type (paroxysmal vs. persistent) and
the frequency of asymptomatic episodes. Conclusions: Patients with
asymptomatic AF Episodes represent a significant proportion after AF
ablation. These patients could be easily overlooked without a proper
monitoring technique. A burden cutoff of 1% and freedom from symptom
should be considered as an ablation endpoint.