Welcome to the Dorothy and Larry Dallas Heart Center at SSM Cardinal Glennon Children's Medical Center.
Your doctor has recommended cardiac catheterization to find out how your child’s heart is working. You probably have questions and concerns about the procedure. This information can help answer many of your questions.
At the time of cardiac catheterization, your child is sedated or given general anesthesia so that he/she does not feel any pain. Then, under sterile conditions, a thin flexible tube (catheter) is placed into the blood vessels in your child’s groin or neck and guided by x-ray (fluoroscopy) toward the heart. Doctors are now able to study how well your child’s heart is pumping and to examine the heart chambers, valves and vessels that take blood into and away from the heart.
After all information is obtained, the cardiologist can then perform an interventional procedure if needed. This is done to improve or cure the heart condition. This includes opening an obstructed valve/vessel or closing an abnormal “hole” in the heart.
Once the procedure is completed, all catheters are removed from the heart. Other terms used to describe cardiac catheterization include angiogram, cardiac cath and heart cath.
Why is catheterization important?
Cardiac catheterization provides more accurate and detailed information about the structure of the heart and how a heart works. It helps doctors diagnose the problem accurately, and lets them choose the best treatment option for your child.
How the heart works
Before discussing cardiac catheterization, it helps to understand how the heart works.
The heart is a hollow organ that constantly pumps blood throughout the body. It is made of strong muscle tissue, called heart muscle (myocardium).
The heart has four chambers: two chambers on the left side and two on the right. The upper chamber on each side, called an atrium, receives and collects blood and then pumps the blood to the lower chambers. The lower chamber on each side, called a ventricle, pumps blood out of the heart.
The left ventricle is the main pumping chamber of the heart. It pumps blood to all parts of the body except the lungs. The right ventricle pumps blood to the lungs.
Four heart valves direct the flow of blood within the heart. The valves act like one-way doors, allowing blood to move forward and preventing it from backing up into the chamber from which it came.
As it beats, the heart pumps blood through a system of blood vessels. These are elastic-like tubes that carry blood to every part of the body. Blood leaves the heart in arteries and returns to it in veins.
The heart pumps blood into the arteries with enough force to keep the blood flowing. Blood pressure is the amount of tension (force) that blood exerts on the walls of the arteries as the heart beats.
How blood circulates
The four heart chambers work together to contract (squeeze) and pump blood. As it circulates, blood delivers oxygen and nutrients throughout the body.
Blood that returns from the body is low in oxygen. This low oxygen blood collects in the right atrium and then flows into the right ventricle. The blood is then pumped into the lungs, where it is enriched with oxygen.
This high-oxygen blood re-enters the heart at the left atrium, then flows into the left ventricle, the heart’s main pumping chamber. Next, the blood is pumped back to the body into the arteries that carry it to all parts of the body.
Preparing for cardiac catheterization
Unless your child is already in the hospital, you will most likely be asked to arrive in the early morning on the day of the procedure.
Your doctor may order several routine tests, such as an ECG, x-ray, or blood tests. Also, prior to the procedure, the house pediatricians at Cardinal Glennon will complete a physical examination on your child to check for any signs of illness.
The cardiologist will speak with you about the procedure, its purpose, benefits and risks. This is a good time to ask any questions and, most importantly, to share any concerns you might have. You will then be asked to sign a consent form.
For your child’s comfort and safety, all cardiac catheterizations at Cardinal Glennon are done under general anesthesia. Therefore, you will be asked to not allow your child to eat or drink anything for 6-8 hours before the procedure. A nurse will contact you several days before the procedure to discuss this. You may be asked to stop some of your child’s medications prior to the procedure, such as digoxin or coumadin.
It is recommended that you bring a list of the names and dosages of all medications your child is taking with you to the hospital.
Tell the doctor or nurse if your child has had an allergic reaction to medications or x-ray dye, or if your child has a history of bleeding problems. It is also important to inform them if your child is sick with a cold, cough or fever. If the child develops an illness before the cath, the procedure will be rescheduled for a different date.
During cardiac catheterization
Cardiac catheterization is performed in a specially equipped x-ray room called a cardiac catheterization laboratory, or simply, cath lab.
Your child will be taken to the cath lab on a stretcher, or movable bed. He/she will be helped onto an x-ray table. The table has 2 large x-ray cameras that can be positioned above and to the side of your child in order to visualize the heart from different angles.
There are also heart monitors and other instruments near by.
The cath lab team generally includes a cardiologist, nurses and technologists. It is here that an anesthesiologist will administer general anesthesia to your child.
The site where the catheters will be inserted is usually in the groin. Sometimes it is in the neck as well. The site is cleansed thoroughly. A local anesthetic is injected into the skin with a thin needle to numb the area.
A needle is used to puncture the blood vessels in the groin. Then, a guide wire (a soft and flexible wire) is threaded into the vein and artery. A short plastic tube, called a sheath, is then slipped over the guide wire and into the vessel. The guide wire is then removed.
Once the sheath is in place, doctors can insert and remove several different catheters without having to use a needle each time.
A catheter is inserted into both the artery and vein, and then guided toward the heart while the staff watches its progress on a television screen. The catheter may be removed and replaced several times. This is done to reach each of the heart chambers or vessels of the heart.
Once the catheter is inside the heart, the doctors can measure the pressures in the different chambers and vessels.
They can also measure oxygen levels in these areas and finally take moving pictures of the blood flowing in and out of the heart.
The procedure generally is not painful and a person cannot feel the catheters as they move through the blood vessels and into the heart. For many, the most difficult part of the procedure is to lie still for a long time on a hard table. Therefore, all children are given general anesthesia to help them with this.
A complete cardiac catheterization procedure usually takes two hours, but can take longer if a cardiac intervention is scheduled. Ballooning of valves or placements of devices to close a “hole” in the heart are examples of interventional procedures. If this is planned, your cardiologist will discuss this prior to the cath and permits will be obtained.
Is catheterization safe?
Because one or more catheters are inserted into the body, catheterization does have some risk. The risk is small, however, and the test is generally safe. Diagnostic procedures carry less than a 1% chance of complication, and interventional procedures carry less than a 3% chance of complication.
Most patients who have catheterization do not have serious complications. However, you should be aware of the risk involved. If you have any questions about your child’s particular risk, ask your doctor.
Benefits of catheterization
Cardiac catheterization provides more accurate and detailed information about how your child’s heart is working. This information helps doctors diagnose the problem accurately and allows them to choose the most effective treatment.
After the catheterization
After the catheters are removed, the doctor or nurse applies firm pressure to the insertion site for 20 minutes, to keep the site from bleeding. Stitches are not required and a large pressure dressing is applied.
Your child will then be awakened from the general anesthesia, and transported to a recovery room for observation.
Because catheters were inserted into the groin, your child will be encouraged to lie flat on his/her back for a period of 6 hours in order to allow the cath site to begin healing properly.
The bedside nurse will check your child’s pulse and blood pressure often, and will also check the insertion site for bleeding. If your child feels sudden pain at the site or if you notice bleeding, let the nurse know right away.
The doctor who performed the procedure will give you some preliminary results soon after the test is over. However, a thorough, detailed analysis of all of the findings will take more time.
At home after the procedure
Limit your child’s activity during the first couple days at home. They can move about, but encourage them not to participate in activity that can cause strain or to lift heavy objects. Also, please have your child avoid frequently going up and down long staircases. After 2-3 days, most children can return to normal activity.
The pressure dressing on the groin remains on until the day after the procedure, unless it should become wet or soiled. The nurse will tell you how to take it off and when it is ok to take a shower or tub bath. A small band aid can be applied for several more days until the puncture site appears healed or scabbed over.
A bruise or small lump under the skin at the catheter insertion site is quite common. It should disappear within a few weeks.
Call your doctor if the insertion site begins to bleed, the bruising or swelling increases, or the leg where the catheters were inserted feels cold or numb. Also call your doctor if the insertion site becomes painful or warm to the touch, of if your child should develop a temperature over 101 degrees F.
Ask your doctor when your child can return to normal activities, such as school or sports, and whether there are things they should not do such as going to the dentist.
Be sure to check with your doctor or nurse about any medication changes.
Your Cardiac Catheterization: Our Guide to Understanding an Important Diagnostic Procedure. Published by: American Heart Association
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