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Heart Disease Health Center

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Electrophysiology Study

How It Feels

You will feel a sharp sting when the local anesthetic is injected to numb your skin at the catheter insertion site.

When the catheter is inserted, you may feel a brief, sharp pain. The movement of the catheter through your blood vessel may cause a feeling of pressure, but it is not usually considered painful. You may feel your heart skip when the catheter touches the walls of your heart. This is normal.

The temperature in the catheterization lab is kept cool so that the equipment does not overheat. For many people, the hardest part of the test is having to lie still for an hour or longer on the hard table. You may feel some stiffness or cramping.

Don't be afraid to speak up if you're worried about anything during the test. The doctors, nurses, and technicians want to know exactly how you're feeling.

It's especially important to tell the doctor if you have any of these symptoms during or after the test:

You may have some soreness and bruising at the insertion site. It is normal for the site to feel tender for about a week. But call your doctor if:

  • Your arm or leg becomes pale, cold, painful, or numb.
  • You have redness, swelling, or discharge from the catheter insertion site.
  • You have a fever.


An electrophysiology study is considered safe. The risks of this test are small.

The more common complications are not serious. They include bleeding or bruising where the catheters were put in.

Serious complications are rare. But they include extra bleeding after the test, puncture of the heart, and damage to the electrical system of the heart that requires a pacemaker.

Very serious complications, such as heart attack or stroke, are very rare.

This test is not usually done during pregnancy, because it involves X-rays. Radiation could damage the developing fetus.

Anytime you are exposed to radiation, including the low levels of X-ray used for this test, there is a chance of damage to cells or tissue. But the risk of this damage is usually very low compared to the possible benefits of the test.

WebMD Medical Reference from Healthwise

Last Updated: March 12, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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