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Electrophysiology Studies

What are electrophysiology studies?

Electrophysiology studies (EPS) are tests that help doctors understand the nature of abnormal heart rhythms (arrhythmias).

What to know:

  • Electrophysiology studies test the electrical activity of your heart to find where an arrhythmia (abnormal heartbeat) is coming from.
  • Your results can help you and your doctor decide whether you need medicine, a pacemaker, an implantable cardioverter-defibrillator (ICD), cardiac ablation or surgery.
  • EP studies take place in a special room called an electrophysiology (EP) lab or cardiac catheterization (cath) lab while you are mildly sedated.
  • During an EP study, about 3 to 5 electrically sensitive catheters are placed inside the heart to record electrical activity.

Why do people have electrophysiology studies?

When someone’s heart doesn’t beat normally, doctors use EPS to find out why. Electrical signals usually travel through the heart in a regular, predictable pattern. Heart attacks, aging and high blood pressure may cause scarring of the heart. The scaring can interfere with the electrical pulses and may cause the heart to beat in an irregular (uneven) pattern. Extra abnormal electrical pathways found in certain congenital heart defects can also cause arrhythmias.

Doctors use EPS to see:

  • Where an arrhythmia is coming from.
  • How well certain medicines work to treat your arrhythmia.
  • If they should treat a problem by destroying the place inside your heart that is causing the abnormal electrical signal, called catheter ablation.
  • If a pacemaker or implantable cardioverter-defibrillator (ICD) might help you.
  • If you are at risk for heart problems such as fainting or heart attack causing sudden cardiac death.