International Circulation: Can you compare the segmental PV isolation with circumferential PV isolation? What is the advantage of either?

　　Roberto De Ponti: In both cases the endpoint of the procedure is to achieve complete isolation of the pulmonary vein as demonstrated by directional conduction block along the line of ablation. The segmental PV isolation is only aimed at the conducting tissue between the vein and the atrium so it is limited along the perimeter of the pulmonary vein walls whereas the circumferential lesion goes around the entire wall. Even very proximal， antral foci can be burned by circumferential PV isolation. So in my opinion circumferential approach is more useful to increase the procedure outcome and long-term follow-up without any antiarrhythmic drug therapy.