The invention generally relates to devices and methods for treating cardiac tissue, including percutaneous closure of cardiac openings such as a patent foramen ovale (PFO) and obliteration of the cardiac cul-de-sacs. The invention includes a device having at least one elongated member. The elongated member has a first material and a second material interwoven with at least a portion of the first material. The second material is capable of transferring energy to tissue in need of treatment.
