Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a catheter shaft with a plurality of electrodes coupled thereto and a processor coupled to the catheter shaft. The processor may be capable of collecting a set of signals from the plurality of electrodes and generating a data set from at least one of the set of signals. The data set may include at least one known data point and one or more unknown data points. The processor may also be capable of interpolating at least one of the unknown data points by conditioning the data set, assigning an interpolated value to at least one of the unknown data points, and assigning a confidence level to the interpolated value.