Complex sentence: An "esophogeal lead" may be used in certain advanced electrophysiology procedures; the esophageal lead uses an electrode placed inside the esophagus, which allows for high quality measurements of the electrical activity of the left atrium.
Split into simpler sentences: An "esophogeal lead" may be used in certain advanced electropysiology procedures. The esophogeal lead uses an electrode placed inside the esophagus, which allows for high quality measurements of the electrical activity of the left atrium.