<International Circulation>:  In your opinion therefore experience is perhaps the most important factor when considering if or if not to go ahead with catheter ablation procedures to treat atrial fibrillation?  
    Dr Riccardo Cappato: Experience is important in every interventional procedure but I would like to emphasize this further when considering catheter ablation for the treatment of atrial fibrillation; this not only for its technical difficulty but also for its logistical considerations whereby you have to select， prepare and oversee appropriate discontinuation of anti-coagulation therapy for suitable patients. Leaving patients heavily anti coagulated during the procedure may add on top of the natural risk of the procedure; bleeding， late bleeding and the risk of haemorrhagic