Toward a novel semi‐invasive activation mapping tool for the diagnosis of supraventricular arrhythmias from the esophagus

Supraventricular arrhythmia diagnosis using the surface electrocardiogram (sECG) is often cumbersome due to limited atrial signal quality. In some instances, use of esophageal electrocardiography (eECG) may facilitate the diagnosis. Here, we present a novel approach to reconstruct cardiac activation maps from eECG recordings. Methods: eECGs and sECGs were recorded from 19 individuals using standard acquisition tools. From the recordings, algorithms were developed to estimate the esophageal ECG catheter's position and to reconstruct high‐resolution mappings of the cardiac electric activity projected in the esophagus over time. Results: Esophageal two‐dimensional activation maps were created for five healthy individuals and 14 patients suffering from different arrhythmias. The maps are displayed as time‐dependent contour plots, which not only show voltage over time as conventional ECGs, but also the location, direction, and projected propagation speed of the cardiac depolarization wavefront in the esophagus. Representative examples of sinus rhythm, atrial flutter, and ventricular pre‐excitation are shown. Conclusion: The methodology presented in this report provides a high‐resolution view of the cardiac electric field in the esophagus. It is the first step toward a threedimensional mapping system, which shall be able to reconstruct a three‐dimensional view of the cardiac activation from recordings within the esophagus.