RS-T Segment Displacement in Induced Coronary Insufficiency as Studied with Esophageal Leads

Abstract
Esophageal electrocardiograms are utilized as a means of studying the left ventricular cavity potentials in induced coronary insufficiency in patients with angina pectoris. Depressions of the RS-T segment recorded in precordial leads after exercise were consistently associated with simultaneously recorded RS-T elevations at the atrial level. These RS-T deviations are interpreted as indicating that in coronary insufficiency there are widespread changes involving the subendocardial aspect of the left ventricle. A circuit is described to enable the recording of better technical esophageal records despite interference due to extraneous low frequency potentials.