Diagnosis & Tests

When you see your healthcare provider regarding a concern about a cardiac arrhythmia, they will likely listen to your heart with a stethoscope, review your medications (including over-the-counter drugs and supplements), and may order blood and other tests as discussed below. It is important to discuss the timing of the symptoms, their relationship to any activity you were doing at the time of the symptoms, and how long and often the symptoms are occurring. These may offer clues to your healthcare provider about the cause of your symptoms.

Electrocardiogram (ECG or EKG) 

This test gives your healthcare provider a “picture” of the electrical activity of your heart. It involves placing wires called electrodes on your chest and other parts of your body and measuring the electrical activity. It is non-invasive (nothing is inserted into the body), does not require any preparation, and can usually be performed in your healthcare provider’s office. 

Echocardiogram (Echo)

An echocardiogram is an ultrasound (or sonogram) of the heart that examines the structural components of the heart, using the same technology as done in pregnant women for prenatal exams.  It uses sound waves (ultrasound) to create an image of the inside of your heart while it is beating.  This test is used to visualize the walls of the heart including the upper chambers (atria) and lower chambers (ventricles) and the valves between the chambers to make sure all structural components of the heart are working correctly.

Stress Test

A stress test lets your healthcare provider see how your heart responds when it has to work harder under stress.  There are different ways this test can be done. The “stress” might be exercising on a treadmill or bicycle. If you cannot exercise, you may be given a medication that makes your heart work harder to mimic the same kind of stress as exercise. Your healthcare provider will compare how your heart works at rest and with stress. To do this, they may use an ECG, an echocardiogram, or a special scan to look at the heart.  

Holter Monitor

To test your heart’s electrical activity over a longer period of time, your healthcare provider might give you a portable monitor to use at home. While you wear the monitor on your shoulder (like a shoulder bag), you can perform all your normal activities, except for showering. You usually wear the monitor for a day or two and then return it to your provider’s office for analysis.  

Event Monitor

Similar to a Holter monitor, an event monitor is used if you have occasional symptoms of irregular heartbeats or dizziness. With most event monitors, you push a button to start the monitor when you feel symptoms, such as fluttering in your chest or lightheadedness. Other event monitors record your heart activity automatically when they pick up irregular heartbeats. You will use the event monitor for several weeks, or until it records enough irregular heartbeats for your healthcare provider to make a diagnosis. This data is then analyzed and allows your provider to make a more accurate determination of whether your symptoms are associated with an irregular heart rhythm (arrhythmia).       

Electrophysiologic Testing

Your arrhythmia may not respond to standard treatment, or your healthcare provider may need more information to diagnose your problem. In this case, they may order this advanced test to monitor your heart’s electrical activity. A cardiologist will thread thin wires embedded with tiny electrodes through a vein in your arm or leg into your heart. Sometimes the cardiologist uses the electrodes to stimulate your heart muscle to help make a diagnosis and determine the best treatment for you.


Last Updated July 2020