Regions of tissue having reduced electrical propagation are created in a bladder to affect its electrical or mechanical properties. To create these tissue regions, a tubular device is advanced through the urethra leading to the interior of the bladder, a distal expandable structure of the device is expanded to contact the inner wall of the bladder, and electrodes or other active energy delivery elements of the device are activated to deliver ablation energy. The electrodes or other active energy delivery elements are disposed over the expandable structure which is shaped to conform to the interior of the bladder. The inner wall of the organ is ablated in a predetermined pattern. The same or other electrodes disposed over the expandable structure can used to electrically map the bladder. This map of electrical activity can be used to create the predetermined pattern.