Esophageal recording
See brief interpretation of 12 lead EKG above
Atrial activity can be closer evaluated using an esophageal electrode. This is due to the close proximity of the atria and the esophagus. In this technique a reference electrode is placed on the chest and an esophageal electrode is swallowed by the patient or placed with a catheter about 40 cm from the teeth right behind the left atrium.
Esophageal EKG recordings may be used to differentiate between different supraventricular patterns. For instance when atrial flutter is suspected, but another tachycardia cannot be ruled out from the surface EKG.
In the esophageal EKG above the lead V4 represents the esophageal electrode. The EKG shows a regular tachycardia, rate 130. Also bifascicular block is seen. The rate of 130 and the impression of a saw-toothed baseline in lead II initially raised suspicion of atrial flutter. The esophageal lead V4 confirms atrial flutter with 2:1 conduction as two atrial signals per QRS complex are seen.
The sharp atrial signals stand out and the QRS complexes are fairly easy identified by comparing the esophageal lead with the other leads.
– Mathias
