What should I expect before an electrocardiogram?

• An ECG is often performed in an office visit.
• Electrodes are placed on your skin.
• Electrodes transmit, but do not generate, impulses.
• The test will last about 30 minutes.
• You should be able to go home on your own.

You will be asked to undress from the waist up and put on a hospital smock that opens in the front. You’ll also need to take off your slacks, panty hose and any jewelry that might interfere with the test.

The technician will position you on a table or bed and will attach the electrodes to your chest and arms or legs and will hook up the lead wires. The technician may ask you for your name and other identifying information, which will be entered into the machine’s computer.

The actual ECG takes only a few minutes. You’ll be asked to lie still and stay silent once the technician turns the machine on. When the tracing is complete, the technician will turn off the machine and remove the electrodes.

Many medicines may change the results of this test. Be sure to tell your doctor about all the nonprescription and prescription medicines you take. If you take heart medicines, your doctor will tell you how to take your medicines before you have this test.

Remove all jewelry from your neck, arms and wrists. Men are usually bare-chested during the test. Women may often wear a bra, T-shirt or gown. You will be given a cloth or paper covering to use during the test.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done or what the results will mean.