Electrophysiology study 

What is an electrophysiology study (EPS)?

An electrophysiology study is a procedure to examine the electrical system of the heart. It analyses the mechanism of abnormal heart rhythms and evaluates the effect of drug therapy.

Your doctor will inject local anaesthetic into the skin in the groin area (and occasionally in the arm). Once the skin has been anaesthetised, small tubes are placed in the vein. Electrode catheters are then inserted with minimal discomfort and positioned at specific locations in the heart.

The electrical system of the right heart is stimulated (paced), recorded and the information is then analysed.

This information will enable your cardiologist to diagnose any abnormality and choose the appropriate treatment.

Why do I need an electrophysiology study (EPS)?

In order for the heart to beat and pump blood to the lungs and the body, the heart is dependent on precise electrical signals that originate from specific areas in the heart. These electrical signals originate from the Sino-Atrial (SA) node (the heart’s ‘pacemaker’) and stimulate the atria to contract and empty blood into the ventricles.

This impulse travels along a pathway to the Atrio-Ventricular node where they spread down specialised conduction fibres in the ventricles. These electrical impulses cause the ventricles to contract, pumping blood to the lungs and body.

When there is a disturbance in the heart’s ability to transmit electrical impulses or these impulses are blocked, this may result in the heart beating too slowly, too fast or irregularly.

The effect of these heart rhythm disturbances can cause dizziness, fainting spells or palpitations.

How long does the procedure take?

An electrophysiology study normally takes about one hour.

How long will I be at the clinic for?

Most day stay patients (those not staying overnight) are normally at the clinic for at least six to eight hours from the time of admission to the time of discharge.

How do I prepare for an electrophysiology study?

Provide informed consent

Your doctor will explain your procedure to you and answer any questions you may have. You will then be asked to sign a consent form. 

You will find a copy of the consent form below. Please download and read this document in advance of your visit. Your doctor will discuss this with you on your arrival, if they have not already done so.

Consent for Electrophysiology Study (EPS)

Download Form

If you have any questions or concerns, or require any additional information about your procedure in advance of your visit, please let your doctor know.

If you have access to a printer, then print your consent form and bring it with you on the day of your procedure. Otherwise we will provide you with a copy on the day to sign with your doctor.

If you have already signed the consent in your doctor’s rooms, then please disregard this instruction.

Contact us the day before your procedure

Please ring us between 11am and 1pm on the day before your procedure [tel: 02 9382 0700] to confirm your time of arrival, fasting and medication instructions. Please ring on a Friday if your procedure is on a Monday.

If you have special needs (these are outlined in the Before my visit patient guide) please let us know one week in advance of your visit.


All patients attending Sutherland Heart Clinic are fasted prior to their procedure. Please follow the fasting instructions that are given to you when you ring us the day prior to your procedure. 


  • All patients must cease solid food six hours before their admission time
  • All patients must cease clear fluids two hours before their admission time (note: clear fluids are NOT cloudy or milky drinks)
  • From two hours before your admission – nil by mouth

For example, if your admission time is 7:00 am (please tailor this to your admission time)

  •   You can eat food up until 1:00 am
  •   You can have clear fluids (water, black tea/coffee, clear juice etc) up until 5:00 am

We will confirm the time of your procedure and when you need to start fasting when you call the clinic the day before your procedure (please refer to our detailed instructions in the Before my visit patient guide).


Patients prescribed Warfarin

If you take the medication Warfarin you will need to consult with your referring cardiologist who will advise you if you need to stop taking your Warfarin three days before your procedure. Your cardiologist may also advise that you need to take a substitute anticoagulant (blood thinner). It is very important that you do not stop taking your Warfarin until you have discussed this with your cardiologist.

Patients prescribed Lasix

On the day of your procedure:

If your procedure is scheduled for before 12:00 pm: Withhold your Lasix and bring in your tablets so staff can give them to you after your procedure

If your procedure is scheduled for after 12:00 pm: you may take your Lasix

Patients with diabetes        

If you are prescribed insulin we suggest you take half your regular insulin dose on the day of your procedure. Remind the booking staff that you are on insulin and we will attempt to schedule your procedure as early as possible.

Insulin dependent (IDDM):  You should take half (½) of your regular insulin dose (please bring in insulin)

Non-insulin dependent (NIDDM) – tablet controlled: You should continue your medication as normal

Non-insulin dependent (NIDDM) – diet controlled: Fast as per the instructions above

Other medications

Oral Sodium Glucose Inhibitors

If you take any of the following medication – Forxiga, Xigduo, Qtern, Jardiance, Jardiamet, Glyxambi, Steglatro, Segluromet, Steglujan – please contact Sutherland Heart Clinic for instructions prior to your procedure.

Aspirin, Plavix, Prasugrel, Ticagrelor, Pradaxa, Apixaban, Rivaroxaban

Your cardiologist will provide advice regarding if and when to stop other medication. All other medications include Aspirin, Plavix, Prasugrel, Ticagrelor, Pradaxa, Apixaban, Rivaroxaban. 

We will discuss your medications with you when you call the clinic the day before your procedure (please refer to our detailed instructions in the Before my visit patient guide).

Skin and nails

There are no special requirements before your procedure in terms of skin care, so just shower or bath as usual. However, do not wear nail polish to your appointment.

What to bring

Please bring your current medications as well as any blood results. Please read our patient guide Before my visit for other items to bring with you on the day, and for how to prepare for your procedure.

Can I drive (or fly) afterwards?

You are advised not to drive or fly for 24 hours after your procedure. Please arrange for someone to drive you home if travelling by car, or to accompany you if you are travelling by taxi or Uber.

Please note that some airlines place restrictions on patients flying after certain procedures. Our staff will be able to provide you with guidance and advice.

What do I need to do after discharge?

​Please make arrangements to have someone at home with you (overnight) on the day of your discharge in the rare event that you need assistance or support.

You can read more about your discharge care in our patient guides: Day of my procedure and After my visit.

What if I have questions or concerns?

If you have any questions about your forthcoming procedure, please contact your referring cardiologist or Sutherland Heart Clinic on tel: 02 9540 8555.

What will happen before, during and after my procedure?

For a detailed overview of how to prepare for your procedure and what to expect before, during and after your visit to Sutherland Heart Clinic, please read the following patient guides:


Before my visit


Day of my procedure


After my visit