An electrophysiology study is a test that evaluates the electrical system of the heart. It is done to find out why someone's heart may beat too slowly or too quickly, or why it does not beat in a regular pattern.

A cardiac electrophysiologist (doctor who specializes in abnormalities of the heart rhythm) performs the test. During the electrophysiology study, the doctor inserts flexible catheters (small wires) into an IV and through the veins and guides them into the heart. Using these catheters, the doctor can look at and record the electrical activity of the heart.  Small electrical impulses can be sent through the catheters to stimulate (pace) the heart.

Sometimes an ablation is done to treat an electrical problem found during an electrophysiology study. An ablation occurs when high-frequency energy is sent through the catheter or a special catheter is used to freeze a small area of the heart to destroy heart cells that are causing the abnormal heartbeat.