ELECTROCARDIOGRAM
An electrocardiogram (ECG, or EKG) is a safe and painless test that examines the heart’s
electrical activity. Special sensors are attached to the body and connected to an ECG
machine, which allows it to record the timing and strength of electrical signals as they
travel through the heart. ECG testing is used to evaluate many types of heart conditions,
including abnormal heart rhythms, heart attack, and changes to the structure of the heart,
such as an enlarged heart.
An abnormal heart rhythm may last only a few seconds, so it may not be recorded during
a normal ECG test. In these cases, an ambulatory cardiac monitor may be used to record
the heart’s electrical activity over 24 hours or longer, in the hope of recording the abnormal
heart rhythm when it occurs. An ambulatory cardiac monitor, such as a Holter monitor, is
a type of wearable, battery-powered ECG device used in these situations. In other cases,
when symptoms occur even less frequently and for even shorter periods, longer-term ECG
monitoring may be required. In these cases, monitors such as event recorders or mobile
cardiac outpatient telemetry (MCOT) devices may be used, depending on how often the
abnormal heart rhythm occurs.
Types of Tests and Monitoring Devices*:
• Electrocardiogram (ECG, or EKG)
• Ambulatory cardiac monitors
• Holter monitor (ambulatory ECG)
• Event monitor (event recorder)
• Mobile cardiac outpatient telemetry (MCOT)
*Not all services may be available at all locations.