Mercy Medical Center North Iowa

Electrophysiology Study

What is an Electrophysiology Study?

An Electrophysiology Study (EPS) is a test to check the electrical activity in your heart. Your heart beats because of electricity that moves along a path in your heart. A large catheter (long, thin, bendable tube) is put into an artery or vein. The artery or vein may be in your arm, in your neck, or in your groin. The groin is the area between your abdomen (belly) and the top of your leg.
Using a TV screen and x-rays, the catheter is gently guided into your heart. Smaller pacemaker wires are put through the large catheter and guided to different areas inside your heart. Your caregiver will send electrical signals through the pacemaker catheters to check for problems. Some problems can be treated during the test.
Why do I need an Electrophysiology Study?
The following are some reasons your doctor feels you may need an EPS:
  • Fainting.
  • Irregular heartbeat.
  • Very fast or very slow heartbeat.
  • To check your heart after a heart attack or cardiac arrest (heart stops).
  • To check to see how medicines for irregular heartbeats are working.
  • To check your heart before and after you get a pacemaker
  • To check your heart before and after you get a defibrillator.
Care Agreement:
You have the right to help plan your care. To help with this plan, you must learn about your health condition and how it may be treated. You can then discuss treatment options with your caregivers. Work with them to decide what care may be used to treat you. You always have the right to refuse treatment.
Most people do not have problems with electrophysiologic studies. However, like with any procedure, there are risks. But the risks involved in not receiving an EPS could result in problems not be detected.

If you don't have an electrophysiologic study your health condition could get worse. You may have irregular heartbeats that cause you to faint. You may have irregular heartbeats that cause your heart to stop. Call your caregiver if you are worried or have questions about your medicine or care.
Getting Ready:
  • You may need to have blood drawn.
  • Do not eat or drink anything (not even water) after:
  • Be at the hospital at:
  • The day of your procedure. Bring with you any papers your caregiver has given you to sign.
  • Your procedure will be around:
  • Ask your caregiver before taking any medicine on the day of your procedure. These medicines include insulin, diabetic pills, high blood pressure pills, or heart pills. Bring a list of your medicines or the pill bottles with you to the hospital.
  • Do not wear contact lenses the day of your procedure. You may wear your glasses.
  • If you are staying in the hospital after your procedure, bring your personal belongings with you. These include your bathrobe, toothbrush, denture cup (if needed), hairbrush, and slippers. Do not wear jewelry or bring money to the hospital.
Informed Consent
You have the right to understand your health condition in words that you know. You may be asked to sign a consent form that gives caregivers permission to do certain tests, treatments, or procedures. If you are unable to give your consent, someone who has permission can sign this form for you. Before giving your consent, make sure all your questions have been answered so that you understand what may happen.
When to Call the Doctor or Seek Medical Care:
You need to call your doctor or seek immediate medical care if:
  • You have signs of a heart attack
  • Chest pain or discomfort that spreads to your arms, jaw, or back.
  • Nausea (sick to your stomach).
  • Trouble breathing.
  • Sweating.
  • This is an emergency. Call 911 for an ambulance to take you to the nearest hospital or clinic. Do not drive yourself!

If you have any questions, ask your health care provider or call the Mercy Imaging Services: 
or 1-800-433-3883, ext. 7200.