An electrophysiology study (EPS) is a procedure used to evaluate and record the electrical activity of your heart. It is not a surgical procedure. It is a diagnostic test that provides a considerable amount of information about your heart rhythm (the speed and pattern of your heartbeat).
There are many reasons for performing an EPS, including:
- To learn the origin and/or nature of your heart rhythm disturbance
- To find a possible cause of dizzy spells or blackouts
- To evaluate how well your medications are controlling your arrhythmia or
- To find out the best treatment modality for your arrhythmia
What happens during the EP study?
An EPS involves the use of insulated wires inserted in the heart to record the normal and abnormal electrical pathways in the heart.
Upon admission to the EP area, electrodes will be placed on your back, shoulders and chest area to monitor your heart rhythm at all times. A blood pressure cuff will be placed around your arm so that your blood pressure may be monitored as well. You will have an intravenous line to give you fluids and medication if necessary.
Your groin and any other site where a wire will need to be placed (possibly arm, neck or shoulder area) will be shaved and cleansed. You will be covered with sterile sheets. The electrophysiologist will give you medication to numb the catheter insertion area(s). The numbing medicine will cause you to feel stinging for a short while but you won’t feel any pain. When the electrophysiologist uses a special needle to find the vein, you will feel some pressure. Let the doctor know if you feel pain at that point. If you do, you will receive more medication. Large tubes (similar to the intravenous) will be passed into the vein(s).
Part of the X-ray machine that guides the electrophysiologist will be placed directly over your body. Special thin, long, flexible insulated wires (electrode catheters) are inside insulated catheters that have been placed and passed into the heart. There is no internal sensation, so this is painless. Sometimes the physicians will insert one of the wires in a vein in the arm or on the side of your neck or in a vein it he area just below your collarbone.
The catheter’s movements are monitored by X-ray pictures on a video screen. These catheters are placed at different sites in the heart and are used to locate the circuit of the abnormal rhythm. Electrical signals will be sent through the catheters to stimulate (pace) your heart in various patterns. The electrophysiologist will try to reproduce the rhythm disturbances, which you might have had before the study. You may feel your heartbeat changing or your heart racing from time to time. Some of the rhythms produced can be very fast and cause some people faint during the test. If this fast rhythm occurs, the electrophysiologist often can pace the rhythm back to normal, or he/she may deliver an electrical impulse to change your heart rhythm back to normal. This will not be felt by the patient.
When the procedure is complete, the catheters will be removed from your groin and pressure will be applied to the area for 5 to 10 minutes to prevent bleeding. Then a dressing will be applied to the area.
How long does the procedure take?
An EPS usually takes 2-4 hours.
What happens after the procedure?
After the procedure, your blood pressure, heart rate and maybe catheter insertions sites will be checked at regular intervals.
You will rest for about 4 hours. You must keep your legs straight without bending the knees. You are allowed to roll back and forth on the bed. You may move your feet and wiggle your toes to relieve stiffness. You will be able to eat as soon as the study is finished.
Your doctor will review your test results and discuss them with you. He/she will explain your treatment options. If no serious arrhythmia was initiated, you will be able to go home on the day of the procedure. You will leave with a dressing on the catheter insertion site(s). Otherwise you will be admitted for monitoring and further treatment will be planned.
What preparations should I make before the EPS?
Consult your physician about your current medication well in advance. You may be told to stop taking certain medications 2-3 days before the procedure. Particular medicines to be reviewed, if you are taking them, are Coumadin, any medicines you are taking for the rhythm issue and any medicines taken for diabetes.
Do not eat or drink anything after 12 midnight on the day before the procedure. You may take approved medications with a small sip of water.
You will have blood tests taken a few days prior and sometimes on the day of the procedure.
You should leave all valuables and money at home or with a relative. Do not wear any jewelry to the hospital. You may wear dentures or dental bridges. Empty your bladder prior to the test. You may receive a mild sedative to help you relax.
Arrange for someone to drive you home after the procedure.
What are the treatment options?
If arrhythmias have been found, the treatment may include: medication, ablation, an pacemaker or an automatic Implantable cardioverter defibrillator.
Medicine: The electrophysiologist may test the effectiveness of certain medications during the EPS and will choose the best one for you.
Catheter Ablation: This technique selectively destroys tissue involved in the short circuit using radio frequency current. This approach eliminates the site of origin of tachycardia or interrupts the pathway through which the arrhythmia travels.
Automatic Implantable Cardioverter Defibrillator (AICD): This device selectively and automatically delivers either pacing or an electrical shock to interrupt ventricular arrhythmias.
What should I do at home?
When you are at home, contact your doctor if you notice any bleeding or swelling, at the insertion site, shortness of breath, coldness or numbness or increasing pain of your arm or leg, a fever or if you feel chest pain.
Avoid heavy lifting for a few days. You will probably be able to resume your normal activities in a day or two. You may shower or clean the site by the next day.