Pediatric Cardiac Catheterization

Cardiac catheterization is a procedure to diagnose and treat certain heart problems. To do this, the health care provider puts a long, flexible tube (catheter) into a blood vessel. The provider then guides the catheter into the heart to find and treat any problems.

In children, cardiac catheterization is done by a pediatric cardiologist who diagnoses and treats heart problems in children. They have special training in cardiac catheterization.

A child might need a cardiac catheterization to diagnose a heart problem (diagnostic cardiac catheterization). Or a child might need a catheterization to fix a problem (interventional cardiac catheterization). The problem is often one that they were born with (congenital heart defect).

Diagnostic catheterization is used less often now. Other tests such as echocardiography, MRI and CT scans are used instead. A diagnostic catheterization may be done to:

• Get a better image of the heart or a heart defect.
• Check the flow of blood through the heart.
• Find pressures in different parts of the heart and lungs.
• Check the heart valves to see if they are working correctly.
• Measure oxygen levels in different parts of the heart, lungs and blood vessels.
• Measure electrical activity in the heart.
• Check for problems after surgery.
• Take tissue samples to be looked at in a lab (biopsy). Biopsies can be used for genetic testing, to check for myocarditis (a type of heart inflammation), or to look for transplant rejection.
• Check the heart before or after heart transplant.
• To decide whether surgery is needed when there is a discrepancy between signs, symptoms and test results.

Interventional catheterization has replaced surgery for some procedures. An interventional catheterization may be done to:

• Close an abnormal opening between the two sides of the heart. This includes percutaneous closure of congenital cardiac defects such as atrial septal defect (ASD), ventricular septal defect (VSD), and patent ductus arteriosus (PDA).
• Close abnormal blood vessels.
• Widen a narrow blood vessel or heart valve. This may include balloon dilation (angioplasty) or stent placement.
• Treat a heart beating too fast or too slow (abnormal heart rhythm).
• Treat arrhythmias by catheter ablation. This is a procedure to stop abnormal electrical signals from moving through your heart and causing an irregular heartbeat.

Cardiac catheterization is usually safe for children. But there are some risks, including:

• Risks from radiation.
• Risks from general anesthesia, if it is used.
• Serious drop in body temperature (hypothermia).
• Decreased oxygen levels (hypoxia).
• Irregular heart rhythm (arrhythmia)
• Injury to the heart, heart valves or blood vessels.
• Blood loss, which could require transfusions.
• Allergic reaction to contrast dye or medicines, including anesthesia.
• Kidney damage from contrast dye.
• Stroke.
• Collapsed lung (pneumothorax).
• Death.

How you get your child ready will depend on their age. If your child is old enough, explain what will happen in a way that they will understand. You might ask the provider, nurse, or a child-life specialist to explain the procedure to your child.

Before your child's catheterization, you should:

• Follow any directions your child is given for not eating or drinking before the procedure.
• Try to keep your child healthy to prevent postponing the catheterization. Keep your child away from people with fevers, colds or other viruses.
• Let the provider know if your child gets sick before the procedure.
• Your provider may tell you to either start or stop giving some medicines to your child.

Your child's provider will discuss the risks and benefits of the procedure with you. You will also need to give written permission (informed consent) to do the procedure.

The procedure is done in a cardiac catheterization lab in a hospital. Your child's provider and a specially trained staff of nurses and technicians will be there during the procedure.

Your child may be given medicine to help them relax (sedation). Or your child will get general anesthesia so they are asleep during the procedure. Once in the cardiac catheterization lab, they will lie on a small table with equipment nearby. In general, here is what will happen:

• The health care team will give your child an injection of numbing medicine (local anesthetic) in the area where the catheter is going to be inserted. This is usually the groin. But other blood vessels may be used instead, such as the vessels in the neck or bellybutton.
• The provider will put a special tube (sheath) into the blood vessel. The provider puts the catheter through the sheath. Sometimes more than one catheter is used.
• The provider guides the catheter through the blood vessel to the heart. The provider uses moving X-rays (fluoroscopy) to help see where the catheter is.

For diagnostic catheterization, the provider may then:

• Take blood samples and measure oxygen levels in each of the four heart chambers and each blood vessel.
• Measure blood pressure in each chamber and each blood vessel.
• Inject contrast dye into the catheter and watch the path the dye takes through the heart (angiography).

If interventions are needed, the provider may:

• Use a balloon to open a heart valve or narrowed blood vessel.
• Put a small support (stent) in the blood vessel to keep it open.
• Use special catheter tips to fix the walls between the upper or lower heart chambers (atria or ventricles) or abnormal blood vessels.
• Use a special catheter tip to open a heart valve with heat.
• Use a special catheter to examine and treat abnormal electrical activity in the heart.

When the catheterization is done, the provider will remove the catheter. They will apply pressure to prevent bleeding. The health care team will put a bandage on the site where the catheter was put in.

Your child will be taken to a recovery room. The health care staff will watch your child closely for several hours. Some children stay in the hospital for a day or more. How long it takes your child to wake up after the procedure will depend on the medicines used. If blood vessels in the leg were used, your child will need to stay in bed and keep the leg straight for a few hours after the procedure. This makes the insertion site less likely to bleed. The site may be bruised and uncomfortable for a few days.

The provider will decide when your child is ready to go home. You will be given written instructions on:

• How to care for the insertion site.
• Signs of infection to watch for, including fever, redness, swelling, pain or drainage.
• Bathing.
• What your child may and may not do.
• Any new medicines.
• Taking your child for follow-up appointments.
• When you should call the provider.

Depending on the results of the cardiac catheterization, your child may need more tests or procedures.