What is an electrophysiology study?
An electrophysiology study (EP study) gives your doctor detailed information about your heart’s electrical activity. Cardiac catheters (long, thin tubes) and computers are used to create electrocardiogram (EKG) tracings and electrical measurements from inside your heart.
The procedure is performed in an electrophysiology laboratory under controlled clinical circumstances. The procedure is performed by cardiologists and nurses who specialize in electrophysiology.
Your doctor uses this test to:
- Find out what is causing your abnormal heart rhythm (also called arrhythmia or dysrhythmia).
- Find out where in your heart the abnormal heart rhythm begins.
- Decide which treatment is best for your abnormal heart rhythm. Your doctor may safely recreate your abnormal heart rhythm during the test to see which medication controls it the best.
Why do I need this test?
Your doctor may recommend an EP study when other tests, such as a standard EKG, Holter monitor, event recorder, stress test, echo or angiogram do not provide enough information about your abnormal heart rhythm.
What are the risks?
An EP study is generally a very safe procedure. However, there are risks with all invasive procedures. We take special precautions to decrease these risks. Please talk to your doctor about any questions or concerns you have about the procedure or its benefits and risks.
Before the Procedure
Should I take my medications?
Ask your doctor which medications you should take. You may need to stop taking certain medications 1 to 5 days before your test. Do not stop taking any medication unless your doctor tells you to.
If you are diabetic, check with your doctor about how to adjust your diabetes medication(s).
Can I eat?
Eat a normal meal the evening before your procedure. DO NOT eat, drink or chew anything after 12 midnight before your procedure. This includes gum, mints, water, etc. If you must take medications, take them with small sips of water. Do not swallow water when you brush your teeth.
What should I wear?
- Wear comfortable clothes.
- Do not wear makeup or nail polish.
- Leave all jewelry (including wedding rings), watches and valuables at home.
What should I bring?
Bring a one-day supply of your prescription medications. Do not take these medications without first talking with the doctor or nurse.
You may bring guided imagery tapes or music and the appropriate player.
Will I be awake?
You’ll get medication through an IV (intravenous line) to help you relax and feel drowsy, but you will not be asleep during the test.
Preparing for the procedure
You will lie in a bed and your nurse will start an IV in a vein in your arm or hand. Medications and fluids are sent through the IV during the procedure.
Your groin area (where the catheters will be inserted) will be prepped and you will be covered with sterile paper sheets (drapes). A soft strap will be placed across your waist and arms to keep your hands from touching the sterile area.
During the Procedure
What happens during the procedure?
The doctor will numb your groin and then insert several catheters into the vein in your groin. The doctor uses the fluoroscopy machine to guide the catheters to your heart.
The catheters sense the electrical activity in your heart and are used to evaluate your heart’s conduction system. The doctor uses a pacemaker to send electrical impulses through one of the catheters to increase your heart rate. You may feel your heart beating faster or stronger. Please tell your nurses and doctor about any symptoms you feel during the procedure.
If your arrhythmia happens during the study, your doctor may give you medications through your IV to see how well they control your heart rhythm. If needed, a small amount of energy will be sent through the patches on your chest to bring your heart back into a normal rhythm.
How long does the procedure last?
The EP study takes 2 to 4 hours.
After the Procedure
How do I care for the incision?
After the procedure, your doctor will remove the catheters and apply pressure to the site to prevent bleeding. You will need to stay in bed and keep your leg as still as possible for 1 to 2 hours.
You will not need stitches. The incision will be covered with a small sterile dressing that can be removed the next day. Keep the area clean and dry.
Contact your doctor if you have any redness, swelling or drainage near your incision.
Will I need to stay in the hospital?
Depending on the results of your test, you may go home or stay in the hospital after the procedure.
Your doctor will talk to you about getting back to your normal activities.
Monitors used during the procedure
- (1) Fluoroscopy: A large X-ray machine positioned above you to help your doctor see the catheters during the procedure.
- (2) Defibrillator/pacemaker/cardioverter: Attached to one sticky patch placed on the center of your back and one on your chest. This allows the doctor and nurse to slow down or speed up your heart rate.
- (3) Electrocardiogram (EKG): Attached to several sticky electrode patches on your chest, as well as inside your heart. Creates a picture on the monitors of the electrical impulses traveling through the heart.
- (4) Blood pressure monitor: Connected to a blood pressure cuff on your arm. Checks your blood pressure throughout the procedure.
- (5) Oximeter monitor: Attached to a small clip placed on your finger. Checks the oxygen level of your blood.
Action Checklist
BEFORE
- Check with your doctor about which medications, if any, you should stop taking before the procedure.
- Do not eat or drink anything after midnight before your test.
- Wear comfortable clothes.
- Do not bring valuables.
- Bring a one-day supply of your medications.
- Talk to your doctor or nurse if you have any questions or concerns about the procedure.
DURING
- You will be closely monitored during the procedure.
- Tell your doctor or nurse about any symptoms you have during the procedure.
AFTER
- You may need to stay in the hospital, depending on the preliminary test results.
- Stay in bed for 1 to 2 hours after the procedure and keep your leg still.
- Keep the incision area clean and dry.
- Call your doctor if you have redness, swelling or drainage at the incision site.
