Electrophysiology study - intracardiac; EPS - intracardiac

You will be told not to eat or drink for 6 - 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 health care 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.

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.

Your doctor 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:

• Test the function of your heart's electrical system
• Pinpoint a known abnormal heart rhythm (arrhythmia) that is starting in the heart, and help decide the best therapy for it
• Determine whether you are at risk for future heart events, especially sudden cardiac death
• See if medicine is controlling an abnormal heart rhythm
• See whether you need a pacemaker or implantable cardioverter-defibrillator (ICD)

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

• Atrial fibrillation or flutter
• Heart block
• Sick sinus syndrome
• Supraventricular tachycardia (a collection of abnormal heart rhythms that start in the upper chambers of the heart)
• Ventricular fibrillation and ventricular tachycardia
• Wolff-Parkinson-White syndrome

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

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

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

• Arrhythmias
• Bleeding
• Blood clots that lead to embolism
• Cardiac tamponade
• Heart attack
• Infection
• Injury to the vein
• Low blood pressure
• Stroke

Miller JM, Zipes DP. Diagnosis of cardiac arrhythmias. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 36.

Olgin JE. Approach to the patient with suspected arrhythmia. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 62.