Atrial fibrillation ablation in adults with congenital heart disease on uninterrupted oral anticoagulation is safe and efficient

Background: The prevalence of atrial fibrillation (AF) is significantly higher in adults with congenital heart disease (ACHD) compared to patients without congenital heart disease (CHD). As AF in ACHD patients might have significant hemodynamic consequences, rhythm control is particularly desirable but rarely achieved by antiarrhythmic drugs. The aim of this study was to investigate safety and long-term outcome of AF ablation in ACHD patients.

Methods: All ACHD patients (n = 46) that underwent AF ablation at our centre from 2013 to 2017 were included in the study. CHD was classified as simple (46%), moderate (41%) or complex (13%). The majority of patients (61%) suffered from persistent AF (paroxysmal AF 39%). Persistent AF was present in 57% of patients with simple, in 58% of patients with moderate and 83% of patients with complex CHD. All patients underwent radiofrequency (RF) ablation on uninterrupted oral anticoagulation. Pulmonary vein isolation (PVI) was performed in patients with paroxysmal AF, whereas patients with persistent AF underwent PVI and ablation of complex fractionated atrial electrograms (CFAE).

Results: No major complications occurred. Single-procedure success after 18 months off antiarrhythmic drugs was 61% for paroxysmal AF and 29% for persistent AF (p = 0.003). Multiple procedures (mean 2.1 ± 1.4) increased long-term success to 82% for paroxysmal AF and 48% for persistent AF (p = 0.05). Long-term ablation success was 64% for simple, 62% for moderate and 50% for complex CHD patients.

Conclusions: AF ablation in ACHD patients is feasible and safe regardless of CHD complexity. Success rates in patients with paroxysmal AF are high and comparable to patients without CHD. In ACHD patients with persistent AF, success rates of ablation are markedly reduced which might be due to a different and/or more extensive (bi-)atrial substrate. In the cohort of complex ACHD patients with persistent AF as the dominant AF type, long-term success of AF ablation is limited.