Background: Circumferential pulmonary vein isolation (CPVI) is increasingly performed for the treatment of symptomatic drug-refractory paroxysmal atrial fibrillation. Long-term data for >10 years after CPVI are sparse. We investigated the long-term clinical outcome and progression of paroxysmal atrial fibrillation after double-lasso and 3-dimensional electroanatomical mapping-guided CPVI. Methods and Results: From 2003 to 2004, 161 patients (mean age: 60±10 years) with symptomatic drug-refractory paroxysmal atrial fibrillation were prospectively enrolled and underwent electroanatomical mapping-guided CPVI. Right-sided and left-sided continuous circular lesions encircling the ipsilateral pulmonary veins were placed with irrigated radiofrequency energy. The procedural end point was the absence of pulmonary vein spikes 30 minutes after CPVI verified by 2 spiral catheters placed within the ipsilateral pulmonary veins (double-lasso technique). Major periprocedural complications occurred in 5 of 161 patients (3.1%). Follow-up was based on outpatient clinic visits, including Holter-ECGs and telephonic interviews. After a single procedure and median follow-up of 129.0 months (interquartile range, 124.7-133.1 months), stable sinus rhythm was present in 53 of 161 (32.9%) patients. Multiprocedural outcome after a mean of 1.73±0.9 procedures and a median follow-up of 123.4 months (interquartile range, 61.0-131.0 months) resulted in stable sinus rhythm in 101 of 161 patients (62.7%). Progression toward persistent atrial fibrillation was observed in 10 of 161 patients (6.2%). Conclusion: Ten-year single-procedural outcome of CPVI in patients with paroxysmal atrial fibrillation resulted in stable sinus rhythm in 32.9% and in 62.7% of patients after multiple procedures. The progression rate to persistent AF was remarkably low.