union of all the center point shapes in a fourth version of step s 400 the planning of an ablation path preferably includes defining tissue that is suitable for ablation via a user and automatically setting an ablation path that passes through the defined tissue via a processor preferably tissue is defined by the user highlighting an area of tissue on a tissue map the highlighted tissue preferably encircles the source of the atrial fibrillation and also approximates the desired ablation path the highlighted tissue is preferably tissue near where the user would prefer the ablation path to occur additionally the user may highlight tissue where ablation should not occur ablation tissue region or where ablation of the tissue should be excluded non ablation tissue region the processor automatically forms an ablation path by defining a shape that falls within the highlighted ablation tissue region and not within the highlighted non ablation tissue region alternatively signal processing of tissue data may be used to automatically define the ablation tissue regions and the non ablation tissue regions this alternative functions to provide an automatic way of defining the ablation path the tissue data may be able to use gap distance tissue thickness tissue motion tissue type tissue angle electrical signal and or any suitable tissue characteristic to aid in finding an optimum ablation path additionally the tissue data may.