Background: For selected patients with atrial fibrillation (AF)-related bradycardia-tachycardia syndrome, ablation of the atrial tachyarrhythmia, primarily AF, has been advocated as an alternative to pacing and maintaining medications. However, data on this approach is sparse. The current study investigated the efficacy of implantable loop recorder (ILR) implantation and catheter ablation of AF related bradycardia-tachycardia syndrome without pacemaker (PM) implantation.

Methods: We retrospectively analyzed a cohort of 8 patients (median age: 77 years; 50% male) with symptomatic AF (paroxysmal: 25%; persistent: 75%) and suspected or documented sinus arrest episodes due to preautomaticity (minimal: 2,6 sec.; maximal: 3,7 sec.). Patients presented with syncope (50%), presyncope (25%), and palpitations (25%) on admission. Pulmonary vein isolation (PVI) was performed in all patients, using cryoballon ablation (5/8; 62,5% patients), radiofrequency ablation (2/8, 25%) and pulsed field ablation (1/8). After successful PVI a subcutaneous ILR was implanted for further rhythm monitoring.

Results:  During a median follow up period of 27 (3, 45) months one patient (12%) needed a  PM. In this patient, PM implantation was necessary due to new onset of third-degree atrioventricular block. Recurrent tachyarrhythmia could be detected in 6 (75 %) patients while bradyarrhythmia occurred in 2 (25%) patients. A total of 7 (88%) patients remained free from syncope and presyncope and without further episodes of preautomaticity after PVI. 

Conclusion: In patients with AF-related bradycardia or symptomatic pre-automaticity pause after AF conversion, PM implantation can be avoided in the majority of patients by a strategy of PVI plus event recorder implantation.