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Heart Catheterization: Getting Ready for the Procedure

Your child needs to have a heart catheterization test (say: CATH-uh-ter-ize-A-shun). You may also hear this called a cardiac catheterization test. This test gives your child's cardiologist (heart doctor) information about how your child's heart is working.

This page explains what happens before, during, and after the test. It will answer some of your questions about your child's test.

Reasons for a heart catheterization test

A heart catheterization test gives your child's cardiologist this information about your child's heart:

  • The structure of your child's heart and its valves. The valves are the folds of tissue that prevent the blood from flowing backwards. The valves are between the parts of the heart called chambers and the blood vessels of the heart.
  • The pressure in the chambers of the heart and its blood vessels.
  • The amount of oxygen in the chambers of the heart and its blood vessels.
  • The amount of blood your child's heart pumps to the rest of the body.
  • The rhythm of the heart.

Talk to your child about the test

Talk to your child using words that he or she can understand. It is important to be honest. Your child will feel less anxious and scared when he or she knows what to expect.

Do not tell your child that there will be no pain or needles. Comfort your child. Tell your child that you will be with him or her as much as you can.

Tell your child that he or she needs the test and that the doctors and nurses are there to help.

Getting ready for the test

Usually, you will visit the pre-catheterization clinic a few days before the heart catheterization test. This will help you and your child get ready for the procedure.

Write the date and time of the clinic visit here:


At the clinic, you will meet with a nurse, who will explain:

  • what your child can eat and drink before the test
  • any medication changes needed before the test
  • what to expect on the day of the test

At the same visit, your child will have one or more of these tests:

  • An electrocardiogram (ECG). This is a recording of the electrical activity of the heart.
  • Blood tests.
  • A chest X-ray. This is a special picture of the inside of your child's chest.
  • An echocardiogram. This is a recording of the positions and movement of the walls of the heart, or the parts inside the heart, such as the valves.

You and your child will also meet with the cardiologist, who will explain the risks of the procedure in a detailed way before you give your consent. "Giving consent" means that you understand the procedure and agree to allow the doctors to perform it.

Eating and drinking before the procedure

Before the heart catheterization test, your child must stop eating and drinking. Please follow these instructions when feeding your child before the test:

Time before procedure

What you need to know

Midnight before the procedure

No more solid food. This also means no gum or candy and Jello.

Your child can still drink liquids such as milk, orange juice, and clear liquids. Clear liquids are anything you can see through, such as apple juice, ginger ale, or water.

6 hours

No more milk, formula, or liquids you cannot see through, such as milk, orange juice, and cola.

4 hours

Stop breastfeeding your baby.

2 hours

No more clear liquids. This means no more apple juice, water, or ginger ale.

Your child's medications

If a change in your child's medications is needed before the procedure, the nurse will discuss this with you at the pre-catheterization clinic visit. Please bring all of your child's medications with you for all visits to the hospital.

Write the instructions here:



The heart catheterization test is done in a special laboratory

Your child will be taken to a special treatment room for the test. This room looks like a small operating room. It is called a catheterization laboratory and it is part of a Cardiac Diagnostic Interventional Unit (CDIU).On the day of the test, your child will need an intravenous line, also called an IV. An IV is a small tube put in a vein of an arm or leg to give your child liquids and medicines.

The health care team will take care of your child

There are usually two doctors, two nurses, and an anesthetist on the heart catheterization team. The anesthetist is a specially trained doctor who gives sleep medicine to your child. This medicine, called a general anesthetic, keeps your child asleep during the test so that he or she feels no pain. The anesthetist will speak to you about these medicines before the test.

Older children may have sedation instead of a general anesthetic. Sedation is medicine given through the IV to calm your child so he or she can keep still for the test.

What happens during the test

The cardiologist carefully puts a long, thin tube called a catheter into a vein or artery in your child's neck or groin. The groin is the area at the top of the leg. Then, the catheter is threaded through the vein or artery to your child's heart.

The cardiologist uses X-rays on a monitor to watch the catheter as it enters the heart. Your child's heart will keep working normally during this test.

The doctor puts a liquid called "contrast" into the chambers of the heart through the catheter. The contrast is a kind of dye that lets the doctor better see the blood flowing. He or she then takes X-ray pictures of the flow of the dye through your child's heart. Your child will get rid of this dye in his or her urine (pee), a few hours after the test.

After the test is finished, the cardiologist takes the catheter(s) out. He or she covers the small wound in your child's groin with a heavy bandage. Your child will not need stitches.

Heart catheterization is sometimes used to treat heart problems

Sometimes the cardiologist uses heart catheterization to treat your child's heart problem. Heart catheterization can be used to close a hole in the heart or blood vessel. It can also be used to stretch a valve or a blood vessel. This treatment is called interventional catheterization. Your child's doctor will explain this treatment if your child needs it.

You can wait for your child during the heart catheterization test

The health care team will tell you where to wait during your child's test. This may be either the CDIU waiting room or your child's in-patient room. If you are not told where to wait, ask the nurse.

How long does the heart catheterization test take?

The cardiologist will tell you how long he or she thinks your child's test will take. The amount of time needed depends on two things:

  • the time it takes to insert the catheter
  • what procedures need to be done during the catheterization

Your child will take a few hours to recover

If your child has a general anesthetic, he or she will wake up in the recovery room. Your child will stay there until he or she is ready for discharge. If your child needs to stay overnight, he or she will be transferred to the in-patient unit.

After you talk to the cardiologist about your child's test, you can ask to see your child in the recovery room.

The nurse will check your child's heart rate, blood pressure, and breathing for about the next 4 hours. He or she will also check the bandage over the place where the catheter was put in and the pulse in the foot of that leg.

Your child will be quite sleepy and may have to stay in bed for a while after the test. When your child is awake, he or she will be able to drink liquids. Soon after that, your child will slowly begin to eat normally again.

The nurse will explain when your child can go back to taking his or her regular medications and if there are any changes. If you have not received information about your child's medications, please ask your child's nurse.

Write any changes here:


Leaving the hospital and going home

When your child goes home depends on how well your child is feeling after the test and the type of procedure your child received. Some children are able to go home on the evening of the test. Others may have to stay in the hospital overnight and go home the next day.

For more information, please see "Heart Catheterization: Caring For Your Child After the Procedure."

What to expect after the heart catheterization test

Your child may have some bruising in the area around the groin. It may be sore for a day or two.

Your child may have an upset stomach for the first day (24 hours) after the test. This is more likely to happen if your child had a general anesthetic.

Your child should only do quiet activities for the first 5 days after the test.

There are risks of complications from the procedure

Generally, heart catheterization is a fairly low-risk procedure. But it is not risk free. Some of the risks of heart catheterization are:

  • clots in the blood vessels
  • bleeding
  • infection
  • problems related to the anesthetic
  • the need for emergency surgery

Getting the results of your child's heart catheterization test

The cardiologist will talk to you about some of the results of your child's test before your child goes home from the hospital. You will get the final results of the test and the plans for your child's treatment after a few days. Your child's cardiologist will call you with these results if there is any additional information.

Key points

  • Heart catheterization is a test that gives your child's doctor information about how your child's heart is working.
  • Your child will need to have some other tests before the heart catheterization test.
  • Before the test, you will be given special instructions on when to stop feeding your child, and any medication changes.
  • Your child will probably have sleep medicine for the test. Your child may need to stay in hospital overnight after the test.
  • Your child's doctor will talk to you about problems that could happen because of the test.

Jackie Hubbert, BScN
Lee Benson, MD, FRCP(C), FACC, FSCAI
Carrie Heffernan, RN, MN
Jennifer Kilburn, RN, MN