methods and apparatus for treating a patient include an ablation device for ablating a target tissue of a patient . the device includes a housing having proximal and distal ends , and an energy source adjacent the distal end of the housing . the energy source comprises an active portion and an inactive portion surrounded by and extending continuously within the active portion . the active portion comprises a first solid material and is configured to emit ablation energy towards the target tissue when the energy source is energized to create a partial or complete zone of ablation in the target tissue . the inactive portion comprises a second solid material different from the first solid material and does not actively emit energy when the energy source is energized .