electrocardiograph (ECG) /-kär″dē·əgraf′/ , a device used for recording the electrical activity of the myocardium to detect transmission of the cardiac impulse through the conductive tissues of the muscle. Electrocardiography allows diagnosis of specific cardiac abnormalities. Leads are affixed to certain anatomical points on the patient’s chest, usually with an adhesive gel that promotes transmission of the electric impulse to the recording device. −electrocardiographic, adj.