Electrocardiogram (ECG or EKG)

Holter monitors record heart activity for up to two days. Electrodes on your chest connect to a small device that collects information throughout the testing period. The device can be worn around your neck or on a belt or shoulder strap. You’ll also be asked to take note of any symptoms while you wear it.

At the end of your test period, your doctor will review the EKG recordings and discuss the next steps.

Event monitors are also portable devices, and there are many different types. Some record your EKG continuously, while others require you to activate the device manually.

A symptom event monitor, for example, allows you to record an EKG when symptoms occur. When you feel a symptom, you hold the monitor to your chest, and it records and stores an EKG reading.

Another type of event monitor goes under the skin of your chest. Called implantable loop recorders, these tools can monitor your heart’s activity for years. These devices deliver wireless transmissions of recordings to a provider, who can alert you if your readings suggest you need immediate medical care.

Just before an EKG test at your provider’s office, you’ll lie on an exam table and a provider will attach electrodes to your chest. They may need to shave your chest to provide a smooth surface for the electrodes.

During an electrocardiogram, the electrodes are connected to an EKG machine, which measures electrical signals in your heart. You will lie still and breathe normally throughout the test. Your provider may ask you to hold your breath at certain points.

The test typically takes between five and 10 minutes.

Once complete, the provider will carefully remove the electrodes. Your reading will be sent to your referring provider. Unless you have an urgent heart condition requiring immediate attention, you can resume your normal daily activities.

Are there any side effects?

EKGs don’t involve electricity going into your body, so there’s no risk of electric shock. You might have some temporary skin irritation once the electrodes are removed. You shouldn’t experience pain or discomfort during the test but alert your provider if you do.

Some medical conditions and other factors, such as taking certain medications or being pregnant, may affect the results. Your doctor will advise you on what to do and not do before the test and inform you of alternative testing, if necessary.