Orthogonal atrial appendage sensing

The characteristics of electrograms derived from a solid platinum-iridium pacing catheter tip in contact with the right atrial appendage are compared to those derived from a Target-tip electrode. Both are then compared to electrograms from two noncontacting orthogonal electrodes positioned more proximally within the atrial appendage. Wave form morphology and spectral energy distribution were determined for the three sets of electrograms. It is concluded that orthogonal electrodes placed within the atrial appendage may offer enhanced atrial sensing required by more sophisticated pacemakers.