Patent ID: 8192428

Claim:
A method for delivering energy to endoluminal tissue, comprising the steps of: providing a catheter configured for endoluminal navigation, a catheter working end comprising a tubular member defining an internal lumen and having an electrosurgical surface including a positive temperature coefficient of resistance (PTCR) material carried in the surface; expanding the tubular member from a first, non-expanded, configuration in which the tubular member is generally straight and the internal lumen extends along a longitudinal axis of the catheter to a second, expanded, configuration in which the tubular member forms a helix such that the internal lumen does not extend along the longitudinal axis but is instead coiled around it; engaging endoluminal tissue with the electrosurgical surface of the expanded tubular member; and delivering Rf current to the endoluminal tissue wherein said Rf current is limited by changes in temperature in at least portions of the PTCR material to prevent arcing, wherein the at least one Rf energy delivery surface comprises at least one helical winding around the tubular member.