Diagnostic cardiac catheterization is a procedure that can be used to evaluate heart problems. During the procedure, a thin, flexible tube (catheter) is inserted through the skin into a blood vessel. It’s then guided into the heart with the help of live X-rays. Cardiac catheterization is done by a pediatric cardiologist. This is a doctor who diagnoses and treats heart problems in children. He or she has special training in cardiac catheterization.

Your child may need this procedure if a heart problem is suspected or to follow a known heart problem. It may also be needed if your child is being prepared for heart surgery and information on the heart is required before treatment.

The procedure allows the cardiologist to:

• Check the structure of the heart and health of the coronary blood vessels

• Check the function of the heart's ability to pump

• Check the electrical activity of the heart

• Check that the valves are working properly

• Measure oxygen levels and blood pressure in the heart and blood vessels

• Don’t give your child anything to eat or drink for 4 to 6 hours before the procedure.

• Follow all other instructions given by the doctor.

Tell your healthcare provider if your child:

• Recently had a cough, fever, runny nose, groin infection, or diaper rash

• Has any allergies, such as contrast dye

• Is taking any medicines

The procedure takes place in a catheterization lab. It usually lasts about 2 to 4 hours. You’ll stay in the waiting room during the procedure:

• Your child lies on an X-ray table.

• Your child is given a pain reliever and a medicine that makes your child relax or sleep (sedative). This is done by mouth or an intravenous (IV) line. He or she may also be given medicine that makes your child sleep and not feel pain (anesthesia). This is done through a facemask or IV. A trained nurse or doctor (anesthesiologist) is in charge of this process.

• A breathing tube may be placed in your child’s windpipe (trachea). Special equipment monitors your child’s heart rate, oxygen levels, and blood pressure.

• A local medicine so your child won’t feel pain (anesthetic) is injected at the catheter insertion site. This can be in the groin, shoulder, or neck.

• Then a catheter is passed through a blood vessel and is guided into the heart. The movement of the catheter can be seen with live X-rays.

• Contrast dye is injected through the catheter. The dye tracks the movement of blood through the heart and allows the structures and blood vessels in the heart to be seen more clearly. Pictures are taken of the heart and blood vessels using X-rays. Any abnormalities will be seen during X-rays.

• Blood samples are drawn from the chambers and blood vessels in the heart. Oxygen levels and blood pressure are measured.

• The catheter is removed once the procedure is complete.

Possible complications include: 

• Reaction to sedative or anesthesia

• Reaction to contrast dye

• Abnormal heart rhythm

• Infection

• Bleeding

• Injury to the heart or a blood vessel (rare)

• Palpitations

• If no immediate treatment for a heart problem is needed, your child will be taken to a recovery room. You can stay with your child during this time.

• It may take 1 to 2 hours for the medicines to wear off.

• Pressure and a dressing may be applied to the catheter insertion site to limit bleeding. The doctor or nurse will tell you how long your child needs to lie down and keep the insertion site still.

• Your child may be given only clear liquids for a few hours. This to prevent reaction to any anesthesia if it was given.

• Any contrast dye your child is given should pass through the body in about 24 hours.

• An overnight hospital stay may be required. You’ll be given instructions for your child’s home care before he or she leaves the hospital.

Call the healthcare provider right away if your child has any of the following:

• Pain, swelling, redness, bleeding, or drainage at the catheter insertion site

• Severe pain, coldness, or a bluish color in the area that held the catheter

• Chest pain

• Shortness of breath

• Irregular heartbeat

• A seizure caused by fever

• Palpitations

Unless advised otherwise by your child’s healthcare provider, call the provider right away if:

• Your child is of any age and has repeated fevers above 104°F (40°C).

• Your child is younger than 2 years of age and a fever of 100.4°F (38°C) continues for more than 1 day.

• Your child is 2 years old or older and a fever of 100.4°F (38°C) continues for more than 3 days.