Implantable loop recorder for augmenting detection of new-onset atrial fibrillation after typical atrial flutter ablation

Heart Rhythm O2. 2021 Apr 28;2(3):255-261. doi: 10.1016/j.hroo.2021.04.003. eCollection 2021 Jun.

Abstract

Background: Patients with typical atrial flutter (AFL) undergoing successful cavotricuspid isthmus ablation remain at risk for future development of new-onset atrial fibrillation (AF). Conventional monitoring (CM) techniques have shown AF incidence rates of 18%-50% in these patients.

Objectives: To evaluate whether continuous monitoring using implantable loop recorders (ILRs) would enhance AF detection in this patient population.

Methods: Veteran patients undergoing AFL ablation between 2002 and 2019 who completed at least 6 months of follow-up after the ablation procedure were included. We compared new-onset AF detection between those who underwent CM and those who received ILRs immediately following AFL ablation.

Results: A total of 217 patients (age: 66 ± 9 years; all male) participated. CM was used in 172 (79%) and ILR in 45 (21%) patients. Median follow-up duration after ablation was 4.1 years. Seventy-nine patients (36%) developed new-onset AF, which was detected by CM in 51 and ILR in 28 (30% vs 62%, respectively, P < .001). AF detection occurred at 7.7 months (IQR: 4.7-17.5) after AFL ablation in the ILR group vs 41 months (IQR: 23-72) in the CM group (P < .001). Eleven patients (5%) experienced cerebrovascular events (all in the CM group) and only 4 of these patients (36%) were on long-term anticoagulation.

Conclusion: Patients undergoing AFL ablation remain at an increased risk of developing new-onset AF, which is detected sooner and more frequently by ILR than by CM. Improving AF detection may allow optimization of rhythm management strategies and anticoagulation in this patient population.

Keywords: Arrhythmia detection and monitoring; CTI-dependent atrial flutter; Implantable loop recorder; New-onset atrial fibrillation; Typical atrial flutter.