The Nature of the RS-T Segment Displacement as Studied with Esophageal Leads

Abstract

The electrocardiographic changes, with particular reference to the RS-T segment and T wave, in surface leads and in esophageal leads reflecting left ventricular cavity potentials, are studied in 7 persons with and without heart disease, before and after the administration of digitoxin. After the administration of digitoxin, the RS-T segment depression in precordial leads and in esophageal leads reflecting the potentials of the posterior surface of the left ventricle, are regularly associated with RS-T segment elevation in esophageal leads reflecting left ventricular cavity potentials. The possible roles played by myocardial involvement due to digitalis, modification of the monophasic curves, and the reduction of the human ventricular gradient are discussed.