Back DefinitionReasons for TestPossible Complications What to ExpectCall Your Doctorrevision Definition An electrocardiogram (ECG or EKG) measures the electrical activity of your heart. The heart generates an electrical signal, which flows out from your heart through your body. Small electrical sensors, called electrodes, are put on your skin to sense the electricity that began in your heart. The electrical activity is then turned into a graph. This can give doctors an idea of whether your heart is beating normally. ECG/EKG Waves Copyright © Nucleus Medical Media, Inc. Reasons for Test An ECG is used to: Diagnose heart attacks and rhythm problems Offer clues about other heart conditions and conditions not primarily related to the heart Detect conditions that alter the body’s balance of electrolytes, such as potassium and magnesium Detect other problems, such as overdoses of certain drugs Symptoms that may prompt an ECG include: Chest discomfort or pain Shortness of breath Palpitations Anxiety Weakness Nausea or the feeling that you have to vomit History of fainting An ECG may also be obtained if you: Are about to have surgery with general anesthesia Are in occupations that stress the heart or where public safety is a concern Are an older adult or have diabetes Already have heart disease Have had a heart-related procedure, such as getting a pacemaker Possible Complications There are no major complications associated with this test. What to Expect Prior to Test You may: Have a physical exam Be asked about your medical history Have your chest shaved if needed Description of Test You will be asked to lie quietly on your back with your shirt off. Six small, sticky pads with attached wires will be placed across your chest. Others will be placed on your arms and legs. The wires will connect to the ECG machine. You will not feel anything during the test. After Test You may resume activities as recommended by your doctor. How Long Will It Take? 3-4 minutes Will It Hurt? No Results Your doctor will interpret the ECG. Based on the results and your other health information, you may need more tests or a treatment plan. Call Your Doctor Call your doctor if you have heart-related symptoms, such as chest pain or trouble breathing. If you think you have an emergency, call for medical help right away. Revision Information Reviewer: Michael J. Fucci, DO; Brian Randall, MD Review Date: 05/2013 - Update Date: 05/20/2013 -