A medical device utilizing temperature sensing to identify or assess anatomical bodies or structures includes an elongate tubular member, at least one electrode, a thermal sensor, and a temperature response assessment system or component. The at least one electrode may be connected to the distal portion of the elongate tubular member, and the one or more electrode can be configured to provide energy or heat to a portion of an anatomical body or structure. The thermal sensor may be configured to measure the thermal response of the portion of an anatomical body or structure, e.g., tissue or blood pools. The temperature response assessment system or component can be coupled to the thermal sensor. In embodiments, the device may include a lumen and port opening, which may accommodate a tool, such as a needle. Methods for using temperature sensing to identify an anatomical body or structure are also disclosed.