The impact of basic atrial rhythm during catheter ablation of atrial fibrillation on clinical outcomes: Lessons from the German Ablation Registry

BACKGROUND: The impact of basic atrial rhythm (sinus rhythm [SR] vs. atrial fibrillation [AF]) during AF ablation on efficacy and safety is unknown.

METHODS: About 3375 patients from the German Ablation Registry undergoing first-time AF ablation were divided according to the type of AF and the basic atrial rhythm during the ablation procedure: paroxysmal AF (PAF) and SR [group Ia], PAF and AF [group Ib]), persistent AF and SR (IIa), and persistent AF and AF (IIb).

RESULTS: Patients in SR (n = 2312 [67%]) underwent cryoballoon ablation more often (Ia vs. Ib p = .002 and IIa vs. IIb p = .010, whereas in patients in AF (n = 1063 [33%]) radiofrequency (RF)-based ablation (Ia vs. Ib p = .006 and IIa vs. IIb p = .014) including left and/or right atrial substrate modification was more frequently performed. Depending on the basic rhythm there was no difference regarding arrhythmia recurrence during long-term follow-up. For patients suffering from persistent AF acute procedure-related complications were more often documented when ablated in AF (9.1% vs. 4.6%, p = .012). which was mainly driven by the higher occurrence of pericardial effusion/tamponade. For patients suffering from persistent AF, favorable results were found regarding 366-day Kaplan-Meier estimates of the incidence of MACCE (death, myocardial infarction, and stroke; p = .011) and the composite endpoint of death, myocardial infarction, stroke, and major bleeding (p = .006), when ablated in SR.

CONCLUSION: Basic atrial rhythm at the time of AF ablation did not affect long-term rhythm outcome. For patients suffering from persistent AF a more favorable acute and long-term safety profile was observed when ablated in SR.