If you have a problem with your heart rhythm (the speed and pattern of your heartbeat), your physician may suggest a procedure called an Electrophysiology Study.  This procedure can help diagnose what is causing your heart rhythm problem and how best to treat it.  Your physician is recommending an EP study because other tests may not have provided enough information about your heart rhythm problem.  EPs can help determine exactly what your heart rhythm problem is and what can be done to control it. A specially trained physician (Electrophysiologist) performs your EP study.

During an EP study, wires are inserted into the heart.  The cells causing your rhythm problem are found.  Electrical signals can be sent through the catheters to stimulate the heart.  If these signals bring on (induce) an arrhythmia, it is monitored.  If you're awake, you may feel your heartbeat changing or your heart racing from time to time.

If an arrhythmia is induced, medications may be given to you through your IV line to test how they affect your heart rhythm and whether they can stop the arrhythmia or keep it from happening.  Arrhythmias may be stopped by using the electrode catheters to regulate (pace) the heartbeat.  Sometimes the heart is given an electric shock (defibrillation) to stop an arrhythmia.
 
In some cases, a catheter ablation may be performed during the EP study to treat an arrhythmia.  The entire procedure takes from 1 to 4 hours.  Your physician or nurse can discuss the procedure with you and answer your questions.