This disclosure provides design, material, manufacturing method, and use alternatives for medical devices. An example medical device includes an elongate shaft having a proximal portion and a distal portion and an expandable member disposed along the distal portion of the elongate shaft. The expandable member includes one or more electrodes disposed thereon. The medical device further includes an ablation electrode disposed adjacent the expandable member and one or more mini-electrodes adjacent the ablation electrode. Additionally, the ablation electrode, the one or more electrodes and the one or more mini-electrodes are electrically isolated from each other.