Original Article

Catheter ablation of atrial fibrillation (AF) is an effective therapy for the reduction of AF burden, improvement of symptoms, and quality of life.1,2 Major complications occur between 3.9 % and 5.1 % and can include thromboembolic complications in 1%.3–6 Although the thromboembolic risk seems to be increased after ablation, there is the suggestion of a reduction in thromboembolic event (TE) rates during long-term follow-up.7 Observational and registry studies have demonstrated low annual rates of TE (strokes and systemic embolism) during midterm follow-up after AF catheter abla-tion ranging between 0.58 and 1.7%,9 thus reaching event rates that are broadly comparable with patients without AF.7,9 Clinical Perspective on p 874 There are only limited data on risk prediction scores for TE after AF ablation. Although previous studies suggest that both the CHADS2 and CHA2DS2-VASc scores, as well as renal dys-function, are useful predictors for thromboembolic complica-tions after ablation, they are hampered by small sample sizes, inclusion of few high-risk patients, incomplete follow-up, and an unknown number of patients on anticoagulation with pos-sible underuse.4,10,11 Renal dysfunction was incorporated in the R2CHADS2 risk score by adding 2 additional points for estimated glomerula