An electrophysiology study (EPS) is a minimally invasive procedure that tests the electrical activity and the conduction system of your heart. This test is used to find out the cause of any rhythm disturbance to the heart and determine the best treatment.
Examples of when an EPS is useful include:
Once the electrical activity is recorded and the study is complete, your doctor may decide the optimal treatment for your rhythm disturbance is medication. If so, he will end the procedure and you will be taken back to the ward soon after. In other cases, he or she may decide that catheter ablation is best. If so, your doctor will most likely proceed directly to perform catheter ablation.
Usually you are admitted on the day of the procedure; occasionally, you will be admitted the day before.
The most common reason to be admitted the day before is to have a pre-procedure trans-oesophageal echocardiogram, which applies to patients who have atrial flutter or atrial fibrillation. This is to out rule the presence of a clot in the left atrial appendage. Your doctor will discuss with you if you would need to go for this procedure prior to the EPS/RFCA procedure.
Most patients can expect to be discharged the day after the procedure. In some cases, hospital stay may be longer, particularly if the patient was previously taking warfarin to thin blood. Therefore, the patient will often be asked to stay in hospital for a few days until their blood has sufficiently thinned out.
The doctor will instruct on what to do before the procedure. Please check before discontinuing any medications with your doctor.
In most cases, you will be told to eat a normal meal the evening before your procedure. However, do not eat, drink or chew anything after 12 midnight before your procedure. This includes gum, mints, water, etc. If you must take medications, only take them with small sips of water. When brushing your teeth, do not swallow any water.
When getting ready, please do not wear makeup and remove nail polish. Wear comfortable clothes when you come to the hospital. You will change into a hospital gown for the procedure. Please leave all jewellery (including wedding rings), watches and valuables at home.
A combination of local anaesthetic (to numb the groin) and sedation will be used so you do not experience pain or undue discomfort during the procedure. This procedure does not require general anaesthetic.
The time to perform the procedure varies greatly depending on the heart rhythm being treated, and your individual circumstances. Cases may be as short as an hour, or last many hours.
Patients with AVNRT or AVRT (including Wolff-Parkinson-White syndrome) can expect their case to take an hour or two. Patients with atrial fibrillation should expect their cases to take between two and six hours.
When it is time for your case, you will be taken to a special area called the Electrophysiology Laboratory. For both electrophysiology studies and radiofrequency ablation:
You will lie on a bed and the Electrophysiology Lab staff will connect monitoring equipment to your chest. They will also start an IV (intravenous) drop in a vein in your arm or hand. The IV is used to deliver any needed medication and fluids during the procedure.
The doctor will then clean the groin using a special soap, and cover you using sterile drapes from your neck to your feet. He or she will then inject local anaesthetic to the skin and give you sedation before starting the EPS or RFCA procedure. You should feel a little sleepy at this point.
He or she will then place a number of catheters (small, thin, flexible tubes) from the groin to the heart under X-ray guidance. You may feel your heart beating fast at certain points, either because of intravenous medication or because your doctor is using the catheters to stimulate your heart.
If your doctor is performing radiofrequency ablation, you may feel a warm (but not painful) sensation inside your chest and/or your face. If you find it uncomfortable, be sure to inform your doctor by speaking out loud; he or she can increase your sedation if needed.
During both EPS and catheter ablation, it is important that you keep as still as possible. Let your doctor know by speaking out loud clearly if you need to move. At the end of the procedure, your doctor will remove all the catheters, and put a tight pressure bandage over the groin site. Once he or she is satisfied bleeding has stopped, you will then be escorted back to the ward on a bed.