An electrophysiology study thoroughly assesses the electrical conduction system of the heart and any abnormal heartbeats. Electrophysiology studies can measure:

• How fast the electrical signals in the heart travel
• How well the electrical impulses are pacing your heart rhythm, and
• Can artificially cause abnormal heart rhythms to learn what triggers them or how they respond to particular drugs.
  

Such tests may be done to check how a pacemaker working, what causes abnormal heart rhythms to start, how effective certain drugs are, where a pacemaker should be implanted or whether more studies are needed.

You will be asked to lie on an X-ray table with a large X-ray camera above it and TV monitors nearby. Heart monitors and other instruments may be nearby. The staff will be wearing sterile gowns with gloves and possibly masks.

You will have cardiac catheterization so that wires can be positioned in the chambers of your heart. You may feel pressure when the catheters are inserted but you should not feel pain. It may become tiring and uncomfortable to lie in the same position so long.

Once the wires are in place, electrical signals from your heart are monitored and recorded. Your doctor may artificially increase your heart rate to cause any abnormal rhythm disturbances. Drugs may be given to you through a needle and tube inserted in your arm. The entire study takes up to three hours.

At Cedars-Sinai's Electrophysiology Laboratory, specially trained doctors conduct these tests. Electrophysiology experts read and interpret the recording of the heart's action and provide a full report to the patient's doctor. The heart specialist can then use this information in planning the best treatment plan.

The For Patients section has instructions for preparing for cardiac catheterization, angiography and electrophysiology studies.