Phone: 301-552-1200
Fax: 301-552-1202

What is it?

The heart contracts 60-100 times a minute to transmit blood throughout the body. Each time the heart pumps blood, it must get an electrical signal to do so. This comes from a network of "electrical wires", the heart's conduction system. During a Cardiac Electrophysiology Study, your doctor can map out the conduction system by recording simultaneous electrical activity in different locations of your heart much like an electrician checks wiring using a multimeter. In some people, the signal starts elsewhere in the heart and/or follows an abnormal electrical pathway. These abnormalities can cause the heart to beat very slowly or very fast resulting in decreased blood supply to the brain and other vital organs and cause the symptoms described earlier.

Why is it important?

Since many arrhythmias occur sporadically, the goal of an electrophysiology study is to duplicate and then evaluate the arrhythmias in a controlled setting. Your doctor can check several different aspects of conduction at one time and decide upon appropriate treatment or need for further testing with you.

Before the procedure
  • If you are taking heart rhythm medications (antiarrhythmic therapy), you may be instructed to stop them about 48 to 72 hours before the test.
  • You will be asked not to eat or drink anything for six hours before the test. You may take sips of water with your medications.
  • If there is a possibility that you are pregnant, be sure to let the doctor know.
  • You will be admitted to the hospital the morning of your test.
  • You may have blood tests, x-rays and an EKG
  • An intravenous (IV) line will be started in a vein in your arm.
  • You'll be taken to the EP lab about 30 minutes before your scheduled test time.
During the Test
  • You will either be awake or mildly sedated and under constant monitoring (blood pressure and heart rate/rhythm).
  • In the EP lab, the areas where the catheters are to be inserted will be shaved and scrubbed with an antiseptic solution.
  • The doctor will numb these areas with a local anesthetic.
  • Catheters may be inserted into veins in your arm or groin and positioned in your heart. You may feel some pressure or slight discomfort as the catheters are inserted, but it should not be painful.
  • Using these catheters, the doctors will try to stimulate any abnormal heart rhythm.
  • If an abnormal rhythm is noted that does not stop by itself, the doctors will try to restore the regular rhythm with medication or by "pacing" the heart.
  • If medication and pacing are unable to stop a very fast rhythm it may be necessary to deliver an electrical shock using patches placed on the chest.
  • It is necessary that you lie as still as possible during the study because the recording equipment is sensitive to any motion.
  • Tell the doctor or nurse right away if you feel palpitations, dizziness, shortness of breath, pain or any symptoms similar to your initial presenting complaints.
  • A typical electrophysiology study takes about sixty to ninety minutes to complete.
After the test
  • Upon completion of the study, the catheters will be removed and pressure applied to the arm or groin to prevent bleeding. The pressure dressing may be left on for several hours.
  • You will return to your room and your blood pressure, heart rate and dressing will be checked regularly by the nurse.
  • Tell the nurse right away if you feel any numbness or tingling in your arm or legs, bleeding from the catheter insertion sites, or other symptoms such as chills or fever.
  • You will lie in bed for four to six hours.
  • It is important to keep your leg and arm straight to prevent bleeding. The nurses or your family can help you with meals during this time.
  • Once the dressing is removed, tell your nurse if you notice any bleeding, swelling, or pain at the catheter insertion site. It is common to have some tenderness and bruising at the insertion site.
  • Your doctor will discuss with you the results of the study and future diagnostic and/or treatment options.
  • Depending on whether an abnormal heart rhythm is found or not, you may go home later the same day or be admitted for further care.
  • Due to the possible need for sedation during the procedure, you should arrange to have somebody else drive you home after the procedure.