Mantle JA, Strand EM, Wixson SE. Med Instrum 1978;12(5):289-92 Routine monitoring of a bipolar atrial electrogram (AEG) simultaneously with the electrocardiogram is a useful and safe clinical technique for the diagnosis of complex cardiac dysrhythmias. The large-amplitude A waves of the AEG can be more reliably identified than the corresponding low-amplitude p waves of the electrocardiogram. Epicardial wires placed during cardiac surgery, catheter-mounted endocardial electrodes, and esophageal electrodes can all be used for routine AEG monitoring. A multipurpose pulmonary arterial catheter with a pair of electrodes, and esophageal electrodes can all be used for routine AEG monitoring. A multipurpose pulmonary arterial catheter with a pair of electrodes mounted on the proximal shaft can be used for combined AEG and hemodynamic monitoring. The equipment needed for AEG monitoring and recording consists of an additional bedside amplifier with 12- to 100-Hz band-pass filter, a dual-channel display scope, and a dual-channel strip chart recorder. Care must be used to keep the atrial electrodes electrically isolated for patient safety. In addition to enhancing the diagnosis and management of dysrhythmias, recording an AEG provides a signal that is suitable for automatic processing.