Electrocardiogram

You will be asked to lie down. A technician will clean several areas on your arms, legs, and chest, and then will attach small patches called electrodes to those areas. It may be necessary to shave or clip some hair so the patches stick to the skin. The number of patches used may vary. The patches are connected by…

Make sure your provider knows about all the medicines you are taking. Some medicines can interfere with test results. Do not exercise or drink cold water immediately before an ECG because these actions may cause false results.

An ECG is painless. No electricity is sent through the body. The electrodes may feel cold when first applied. In rare cases, some people may develop a rash or irritation where the patches were placed.

An ECG is used to measure: Any damage to your heart How fast your heart is beating and whether it is beating normally The effects of medicines or devices used to control your heart (such as a pacemaker ) The size and position of your heart chambers An ECG is often the first test done to determine whether a person has…

Normal test results most often include: Heart rate: 60 to 100 beats per minute Heart rhythm: Consistent and even

Abnormal ECG results may be a sign of: Damage or changes to the heart muscle Changes in the amount of the electrolytes (such as potassium and calcium) in the blood Congenital heart defect Enlargement of the heart Fluid or swelling in the sac around the heart Inflammation of the heart (myocarditis) Past or current…

There are no risks.

The accuracy of the ECG depends on the condition being tested. A heart problem may not always show up on the ECG. Some heart conditions never produce any specific ECG changes.

Brady WJ, Harrigan RA, Chan TC. Basic electrocardiographic techniques. In: Roberts JR, Custalow CB, Thomsen TW, eds. Roberts and Hedges' Clinical Procedures in Emergency Medicine and Acute Care . 7th ed. Philadelphia, PA: Elsevier; 2019:chap 14. Ganz L, Link MS. Electrocardiography. In: Goldman L, Cooney KA, eds.…