This is an across the chest interpretation of the electrical activity of the heart over a period of time, as detected by electrodes attached to the outer surface of the skin and recorded on a strip of paper for diagnostic interpretation. The tracing of electrical activity is used to measure the rate and regularity of heartbeats, as well as the size and position of the chambers of the heart and the presence of any damage to the heart. In addition to thoracic x-rays and echocardiography, specific heart conditions can be diagnosed appropriately and therapy can be instituted to alleviate clinical symptoms.