An electrocardiogram (ECG / EKG) is an electrical recording of the heart and is used in the investigation of heart disease. It is a graphic display of the electrical activity of the heart. An ECG may be done as part of a routine physical exam. It may be repeated any time there are questions about the working of your heart. You will be brought to the ECG department in the centre. The technician will ask you to take off your clothing from the waist up, put on a gown, and lie down on a small bed. The technician will place a small electrode (a small self-sticking plastic patch) on each of your arms and legs and across six areas on your chest. You need to lie still for the minute or two that it takes the machine to make a record.