A tissue lesion creating device (30) is structured and arranged to be insertedthrough the vascular system into a body vessel adjacent the heart and to besubsequently subjected to a change of shape in order to penetrate into theheart tissue. The tissue lesion creating device may thus be used for treatingdisorders to the heart rhythm regulation system. A kit of devices (30, 38, 54,68, 82, 100) provides a plurality of devices for creating a lesion pattern fortreating such disorders.