A medical device and method are provided for mapping and therapeutic treatment, which may include a source of cryogenic fluid, a balloon or other expandable member in fluid communication with the source of cryogenic fluid, and a plurality of electrodes on the expandable member. The medical device may include a catheter or elongate body, and the electrodes may take the form of longitudinal strips. The expandable member may take the form of an inner and outer balloon, and the electrodes may be on the outer balloon. The electrodes may be on a proximal or distal conical portion of the expandable member, or both. An electrical insulator may be provided covering a portion of the electrodes.