Heart Disease and Electrophysiology (EP) Testing
An electrophysiology (EP) study is a test that records the electrical activity and the electrical pathways of your heart. This test is used to help determine the cause of your heart rhythm disturbance and the best treatment for you. During the EP study, your doctor will safely reproduce your abnormal heart rhythm and then may give you different medications to see which controls it best or to determine the best procedure or device to treat your heart rhythm.
Why Do I Need an EP Study?
You may need an EP study:
- To determine the cause of an abnormal heart rhythm
- To locate the site of origin of an abnormal heart rhythm
- To decide the best treatment for an abnormal heart rhythm
Sometimes, an EP study is conducted before implantable cardioverter/defibrillator (ICD) placement to determine which device is best, and then afterward to monitor treatment success.
How Should I Prepare for the EP Study?
- Ask your doctor what medications you are allowed to take during the EP study. Your doctor may ask you to stop certain medications 1 to 5 days beforehand. If you have diabetes, ask your doctor how you should adjust your diabetes medications.
- Do not eat or drink anything after midnight the evening before the EP study. If you must take medications, take them only with a small sip of water.
- When you come to the hospital, wear comfortable clothes. You will change into a hospital gown for the procedure. Leave all jewelry or valuables at home.
- Your doctor will tell you if you can go home or must stay in the hospital after the procedure. If you are able to go home, bring a companion to drive you home.
What Can I Expect During the EP Study?
- At the start of an EP study, you will lie on a bed and the nurse will start an intravenous (IV) line into your arm or hand. This is so you can receive drugs and fluids during the procedure. You will be given a drug through your IV to relax you and make you drowsy, but it may not put you in a total sleep.
- The nurse will connect you to several monitors.
- Your groin will be shaved and cleansed with an antiseptic solution. Sterile drapes are used to cover you, from your neck to your feet. A soft strap will be placed across your waist and arms to prevent your hands from coming in contact with the sterile field.
An electrophysiologist (a doctor who specializes in the diagnosis and treatment of abnormal heart rhythms) will numb the skin in your groin (a few inches to the side of your genitalia) with medication and then insert several catheters, or tubes, into the vein beneath the skin. Guided by the fluoroscopy machine, the catheters are threaded to your heart. The catheters sense the electrical activity in your heart and are used to evaluate your heart's conduction system. The doctor will use a pacemaker to deliver the electrical impulses through one of the catheters to increase your heart rate.