 Since no data exist on the time course of the deployed ablation lines. Do patients with recurrences of AF always have PV reconduction ? Vice versa, it also remains unclear if all patients with stable sinus rhythm do experience this effect based on longterm PV isolation. To assess the significance of the time course of PV isolation, the proposed study protocol consists therefore of an invasive re-evaluation of all primarily ablated pts scheduled after 3 months of follow-up regardless of arrhythmia recurrence to investigate PV conduction properties. 