Electrophysiology Study - "EPS"

An electrophysiology study, or EPS, identifies irregular heartbeats and looks at how well your heart's electrical system works.

What is an EPS study?
Why do I need an EPS study?
What are the risks of having an EPS study?
How do I prepare for an EPS study?
What happens during an EPS study?
What happens after an EPS study?

What is an EPS study?

An EPS (electrophysiology study) looks at how well your heart’s “electrical circuit” works. It can also identify irregular heartbeats (arrhythmias).

Why do I need an EPS study?

An EPS can help your doctor to:

• See how well your heart’s electrical system is working
• Find the source and type of abnormal heart rhythm
• Decide the best treatment for your arrhythmia
• Identify the cause heart palpitations, dizzy spells or blackouts
• Assess your risk of further heart rhythm problems
• Decide if you need additional treatments, such as medications, pacemaker surgery, an implantable cardioverter defibrillator (ICD), catheter ablation or bypass surgery

You may also need an EPS if you have had an abnormality detected on any of the following tests:

• ECG
• Holter Monitor
• Loop Recorder
• Stress Testing

What are the risks of having an EPS study?

While serious risks are unlikely, there are some risks associated with an EPS procedure. 

The most common risk for this procedure is bruising or swelling at the puncture site in the leg.

Less common complications are:

• Abnormal heart rhythms, called arrhythmias, needing restoration of heart rhythm with cardioversion
• Major bleeding or bruising at puncture site
• Blood clot in lung or legs
• Death from this procedure is very rare

Your doctor will have a more detailed discussion about risks before you agree to the surgery. Your doctor will ask you to sign a consent form to agree to the procedure.

How do I prepare for an EPS study?

There are a few simple steps you need to take to prepare for your EPS which usually include:

• Not eating or drinking (fasting) for 6 hours before the test
• Checking with your doctor about taking your usual medications - especially if you take medication for diabetes because you will be fasting. If you take SGLT2 medicine for diabetes, you will need to stop taking them at least 3 days before your surgery. Read our Patient Information Guide on SGLT2 inhibitors for diabetes.

What happens during an EPS study?

The EPS test takes place in the Electrophysiology Lab in the hospital. Before the test begins, you’ll be given sedation (Midazolam/Fentanyl) to help you relax. This is given through a cannula in your arm. During the procedure:

• Your groin (top of right or left thigh) area is shaved
• A local anaesthetic numbs the area
• Catheters are inserted into sheaths, gently passed through veins until they your heart
• An x-ray machine guides the catheters to your heart
• Your doctor uses electrical impulses to make your heart beat at different speeds
• You may need medication or a brief shock to control your heart beat  
• Your heart beats are recorded

The EPS test takes between one and two hours. Your heart might feel like it’s beating stronger or faster during the test.

What happens after an EPS study?

After your EPS is finished, your doctor will remove the catheters and apply pressure, followed by a dressing. You’ll be watched closely in a recovery area, and depending on how you feel, you might need to rest in bed for a while. Most people can return to their normal activities over the next few days. Your doctor will discuss the results of your test and determine the best treatment for you.