Cardiac Electrophysiology

An electrophysiology (EP) study — also called invasive cardiac electrophysiology — is a series of tests that examine your heart’s electrical activity.

The heart’s electrical system produces signals (impulses) that control the timing of your heartbeats. During an EP study, doctors can create a very detailed map of how these signals move between each heartbeat.

An EP study can help determine the cause of heart rhythm problems (arrhythmias). Sometimes it’s done to predict the risk of sudden cardiac death.

An EP study is performed in a hospital by heart doctors (cardiologists) with special training in heart rhythm disorders (electrophysiologists).

Why it’s done

An EP study gives your doctor a very detailed look at how electrical signals move through your heart. Your doctor may recommend an EP study if:

You have an abnormal heart rhythm (arrhythmia). If you’ve been diagnosed with an irregular or fast heartbeat — such as supraventricular tachycardia (SVT) or any other type of tachycardia — your doctor may do an EP study to determine the best treatment.

You fainted. If you had a sudden loss of consciousness (fainting, or syncope), an EP study can help understand the cause.

You’re at risk of sudden cardiac death. If you have certain heart conditions, your doctor may recommend an EP study to better understand your risk of sudden cardiac death.

You need cardiac ablation. Cardiac ablation uses heat or cold energy to correct heart rhythm problems. An EP study is always done before cardiac ablation to pinpoint the area of the abnormal heart rhythm. If you’re having heart surgery, you may have cardiac ablation and an EP study on the same day.