Basic Electrocardiography

Abstract

The intrinsic depolarization and repolarization of the cardiac musculature produces radiating electrical fields which are manifest on the surface of the body as minute changes in skin voltage or potential. An electrocardiograph is a machine designed to measure the differences in electric potential between two electrodes located on the skin, and to record these changes on paper. The machine consists of skin electrodes, a high-gain amplifier to amplify the electric charge received by the electrodes, a sensitive galvanometer to measure the differences in voltage between two electrodes, and a recording device for transcribing these differences on paper or some other recording medium.