Common Tests to Diagnose Arrhythmias

Your doctor may perform tests to check for heart disease or other problems that may cause arrhythmias.

  • ECG: Records your heart’s electrical activity using electrodes placed on your skin. An ECG measures the timing and duration of each electrical phase in the heartbeat.
  • Echocardiogram: An echocardiogram is a noninvasive (the skin is not pierced) procedure used to assess the heart's function and structures. During the procedure, a transducer sends out sound waves at a frequency too high to be heard. When the transducer is placed on the chest at certain locations and angles, the sound waves move through the skin and other body tissues to the heart tissues, where the waves bounce or "echo" off of the heart structures. These sound waves are sent to a computer that can create moving images of the heart walls and valves. This can help diagnose structural problems that can cause arrhythmias.
  • Holter Monitor: A portable device that records a continuous record of the electrical activity of your heart for 24-48 hours; this records rhythm abnormalities that occur that may be undetected on the office ECG. Arrhythmias may last only a very short time and not be seen on during the shorter recording time of a regular ECG. While wearing a Holter monitor, you can go about your daily activities.
    For suspected arrhythmias that occur infrequently or pass quickly, your doctor might suggest that you wear an event recorder.
  • Event Monitoring: Various kinds of event monitors attach with bracelets, finger clips or patches worn under the arms for a month or two. The data about your heart’s electrical system are recorded and stored. You can then transmit the results to your doctor to be analyzed.
  • Implantable loop recording (ILR): A small device that’s surgically implanted under the skin on your chest. It allows your doctor to monitor your heart function remotely, for up to two years.

If a physician doesn't find an arrhythmia during the above tests, they may try to trigger the arrhythmia with other tests, including:

  • Tilt Table: This test evaluates the potential reasons for fainting, or syncope. Heart rhythm and blood pressure are carefully monitored while a patient rests on the table.
    Stress Test: Some arrhythmias are triggered or worsened by exercise. During a stress test, the heart's activity is monitored while you ride on a stationary bicycle or walk on a treadmill. If you have difficulty exercising, a drug may be given to stimulate the heart in a way that's similar to exercise.
  • Electrophysiology Study (EP Study): A doctor threads thin, flexible tubes (catheters) tipped with electrodes through the blood vessels to different areas within the heart. Once in place, the electrodes can map the spread of electrical impulses through the heart. Doing this helps the doctor determine the location of the arrhythmia, its possible causes and the best treatment options. This test may also be done to determine if a person with certain health conditions is at risk of developing heart arrhythmias.