Abnormal Heart Rhythm: Diagnosis

If you have an abnormal heart rhythm, you may see a heart rhythm specialist, called an electrophysiologist or EP doctor. The EP doctor may do the following tests to help diagnose your problem.

  • Medical, family and social history and physical exam
  • Blood tests
  • Electrocardiogram (12-lead ECG)
    An EKG measures your heart's electrical impulses and prints them on graph paper. To perform this painless test, we place small electrodes on the skin of your chest, arms and legs for a short time.
  • Echocardiogram
    The technologist places a small probe on your chest and uses sound waves to make an image of your heart.
  • Holter monitor
    Your abnormal rhythm may not happen during the EKG. A Holter monitor can record your heart activity for 24 hours or longer. You wear a small, portable recorder and electrodes on your chest. The electrodes record the electrical activity of your heart. Listen to a podcast about the holter monitor test.
  • Event recorder
    If your rhythm problem isn’t recorded on the Holter, you may need to use an event recorder for a month or longer. Event recorders come in various styles. One looks like a thick credit card that can be carried in a pocket or purse and placed on your chest when you have symptoms. You wear another, attached to your chest all the time. The recorders send information by computer to your doctor. If the rhythm recorded is serious, your doctor will get a call right away.
  • Implantable loop recorder, or ILR
    If you have fainting or syncope, you may need an implantable recorder. The doctor places it under the skin of your chest to record your heart for up to two years.
  • Electrophysiology study (EP study)
    The doctor inserts a catheter, or thin, flexible tube, into a blood vessel and guides it to your heart. It measures your heart’s electrical activity and helps the doctor see the abnormal pathway causing the arrhythmia.

Holter and event monitoring devices

Patient education – video links

Electrophysiology study

Implantable loop recorder

Patient education – narrative information

Cardiac tests to diagnose rhythm disorders