This trial is an operator-blinded, acute, single-visit observational trial in humans. Enrollment will include 25 patients undergoing a radiofrequency ablation procedure in which ablation of the cavotricuspid isthmus is planned. Electrogram characteristics of the small, imbedded pin electrodes will be compared to standard bipolar EGMs utilizing the ablation tip electrode and ring. Absolute voltage, voltage reduction, and frequency spectra will be examined before, during, and after ablation. EGM characteristics of standard and "ultra-local" recordings will be compared in their ability to accurately identify an effective RF lesion as defined below.
