Electrophysiology Study (EPS)

An Electrophysiology Study looks at how well your hearts “electrical circuits” work.

It is a test performed to assess your heart’s electrical system or activity and is used to diagnose abnormal heartbeats or arrhythmia. The test is performed using catheters and wire electrodes, which measure electrical activity through the heart chambers.

The procedure can be performed here at Ascot Angiography by a Cardiac Electrophysiologist, assisted by anaesthetists, nurses and technicians.

An EP Study may be recommended by your Cardiologist as a diagnostic tool to help them:

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

You may also need an EP Study if you have had an abnormality detected on another test, such as an ECG or Holter Monitor test.

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

• Having a pre-operative blood test
• Having a pre-operative CT scan, (depending on your procedure type)
• Not eating or drinking (fasting) for 6 hours before the test
• Checking with your doctor about taking your usual medications – especially if you take medications for Diabetes, because you will be fasting.
• Bringing a list of all medications you are currently taking
• Arranging for a friend or family member to drive you to and from the hospital
• Telling your doctor or nurse about any allergic reactions you have experienced from medications, including contrast media (dye) used in x-rays.

The EP Study is performed by a Cardiac Electrophysiologist assisted by specialised anaesthetists, nurses, and technicians in the angiography suite here at Ascot Hospital.  The team will do their best to make  you as comfortable as possible as you lie on the procedure table.  You will notice there are television screens, heart monitors and various pieces of equipment close by that are used by the doctor and nurses during the EP Study.

Before the procedure starts, a small needle will be inserted into a vein in your arm.  This allows for medications to be injected directly into the vein if necessary.

A nurse will shave and clean the groin and possibly neck area where the catheters will be inserted.  A local anaesthetic will be administered with a tiny needle to numb this area.

Electrodes will be placed on your chest and back to connect you to the monitoring equipment. A blood pressure cuff will be placed on your upper arm to monitor your blood pressure.

One or more catheters will be inserted into a large vein in your groin and guided to your heart.  Our staff will be following the progress of these the entire time on the monitor.

There are two parts to the EP Study:

• Recording the hearts electrical signals
• Pacing the heart to bring on certain abnormal rhythms

Medications are sometimes used to stimulate your arrhythmia.  When this happens, you may feel your heart racing or pounding but you needn’t be alarmed.  In the controlled environment of the EP laboratory, induced arrhythmias are handled by well trained personnel with state-of-the-art equipment.  This is an important tool that allows your doctor to gain information about your arrhythmia that will help them treat it.

Whilst the procedure is not usually painful, you may feel some pressure when the catheters are inserted.

Depending on the study you undergo, you may be given medications intravenously, administered in your arm, to sedate or make you sleepy (called conscious sedation). These medications help to reduce any anxiety and relieve discomfort. You may have a general anaesthetic. Your Cardiologist will let you know which form of sedation is going to be used.

An EP Study can take between one and four hours. Which tests you undergo during an EP Study will depend on your condition and the reason for your test.

You are welcome to have a support person with you until you enter the Angiography Theatre.

You will need to ask a friend/relative to drive you home and you should not be alone on the night following your procedure.

Following your EP Study, you will be moved to a recovery area to rest quietly for four to six hours.  Your heartbeat and blood pressure will be monitored continuously during this time.  Most people go home the same day, although your Cardiologist may require you to stay overnight.  It is normal to feel some soreness for a few days where the catheter was inserted.

Your Cardiologist will share the results of your EP Study with you after the test – most often in a follow-up appointment.  He or she may also make recommendations for treatment based on the results.  A letter will be sent to your GP giving the results of you EP Study.