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Intracardiac electrophysiology study (EPS)

Electrophysiology study - intracardiac; EPS - intracardiac; Abnormal heart rhythms - EPS; Bradycardia - EPS; Tachycardia - EPS; Fibrillation - EPS; Arrhythmia - EPS; Heart block - EPS

Intracardiac electrophysiology study (EPS) is a test to look at how well the heart's electrical signals are working. It is used to evaluate abnormal heartbeats or heart rhythms.

Images

Heart - front view
Conduction system of the heart

Animation

Cardiac conduction system

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How the Test is Performed

Wire electrodes are placed in the heart to do this test. These electrodes measure electrical activity in the heart.

The procedure is done in a hospital laboratory. The staff will include a cardiologist, technicians, and nurses.

To have this study:

Other procedures that may also be done during the test:

How to Prepare for the Test

You will be told not to eat or drink for 6 to 8 hours before the test.

You will wear a hospital gown. You must sign a consent form for the procedure.

Your health care provider will tell you ahead of time if you need to make changes to the medicines you regularly take. Do not stop taking or change any medicines without first talking to your provider.

In most cases, you will be given medicine to help you feel calm before the procedure. The study can last from 1 hour up to several hours. You may not be able to drive home afterward, so you should plan for someone to drive you.

How the Test will Feel

You will be awake during the test. You may feel some discomfort when the IV is placed into your arm. You may also feel some pressure at the site when the catheter is inserted. You may feel your heart skipping beats or racing at times.

Why the Test is Performed

Your provider may order this test if you have signs of an abnormal heart rhythm (arrhythmia).

You may need to have other tests before this study is done.

An EPS may be done to:

What Abnormal Results Mean

Abnormal results may be due to abnormal heart rhythms that are too slow or too fast. These may include:

There may be other causes that are not on this list.

The provider must find the location and type of heart rhythm problem in order to determine the proper treatment.

Risks

The procedure is very safe in most cases. Possible risks include:

Related Information

Arrhythmias
Holter monitor (24h)
Sick sinus syndrome
Wolff-Parkinson-White syndrome (WPW)
Ventricular tachycardia
Cardiac ablation procedures

References

Ferreira SW, Mehdirad AA. The electrophysiology laboratory and electrophysiologic procedures. In: Sorajja P, Lim MJ, Kern MJ, eds. Kern's Cardiac Catheterization Handbook. 7th ed. Philadelphia, PA: Elsevier; 2020:chap 7.

Nattel S, Tomaselli GF. Mechanisms of cardiac arrhythmias. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12th ed. Philadelphia, PA: Elsevier; 2022:chap 62.

Olgin JE. Approach to the patient with suspected arrhythmia. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 56.

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Review Date: 5/8/2022  

Reviewed By: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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