Diagnostic Tests

To help determine the function of your child’s heart, the following tests may be ordered:

  • Blood Count
    The blood count is a test to determine the type and number of blood cells present. Certain heart problems may cause the blood count to be abnormal. The test is done by drawing blood from a vein or by pricking your child’s finger or heel. You may remain with your child while blood is being drawn. Some children need to have additional tests.
  • Cardiac Event Recorder (CardiobeeperTM)
    The CardiobeeperTM is a small device used to record problems with the heart’s rate or rhythm (arrhythmia), which occur only occasionally. It is the size of a cigarette pack and is placed on the chest for 30 seconds whenever the child feels his heart is beating unusually. The device records the EKG pattern. The graph pattern is sent to the doctor from the monitor by telephone. The CardiobeeperTM is used at home for one month.
  • Chest X-ray
    A chest X-ray is a picture that shows the size and the shape of the heart, lungs and major blood vessels. If the child is old enough to cooperate, he will be asked to hold his breath and be still for two to three seconds while the picture is taken. The amount of radiation used for a chest X-ray is very small and is not dangerous. Usually parents are asked to wait in a nearby room while the X-ray is being taken. A technologist will remain with your child and provide any special help he needs.
  • Dobutamine Stress Echocardiogram (DSE)
    The DSE is useful in diagnosing coronary artery disease (blockages in arteries supplying blood to the heart muscle). An echocardiogram is performed while the child is resting and again while dobutamine is slowly injected into a vein. Dobutamine is a potent medicine causing the heart to pump faster and harder. Normally, all areas of the heart muscle pump more vigorously while this medicine is being given. If this vigorous pumping is not seen on the echocardiogram, it may indicate a blocked or narrow coronary artery.
  • Electrocardiogram (EKG or ECG)
    The heart has a special electrical system that enables it to beat. An EKG records the work of this system on graph paper. It gives information about the rhythm of the heartbeat, the size of the chambers of the heart and the amount of blood going to the heart muscle itself.

    An EKG is a painless test and takes only a few minutes to complete. It is performed by placing small sensors (electrodes) on your child’s wrists, ankles and chest. The most accurate EKG is obtained while your child is lying quietly on the examination table. If your child is anxious, you may help comfort him by holding his hand or talking with him.
  • Echocardiogram (ECHO)
    An ECHO creates a moving picture of your child’s heart by using high frequency (ultrasound) sound waves. Three small stick-on patches (electrodes) are placed on your child’s chest. Then, a small microphone-like instrument (transducer) covered with a jelly substance is moved slowly over the chest. The ECHO produces the picture of the beating heart on a TV screen. The equipment also can show the direction of the blood flow through the heart. Portions of the test are recorded on paper and videotape.

    The ECHO is painless except for the feeling of slight pressure as the transducer is moved over the chest. The transducer may make noises when it is moved in different positions. Your child needs to lie quietly on the examination table during the test. Young children who are restless may need to be given sedation by mouth. To improve the quality of the picture on the screen, the ECHO is done in a dimly lit room.

    The length of time needed to complete the ECHO varies greatly. It may last from 30-60 minutes. The technologist will try to complete the ECHO as quickly as possible. Parents may remain with their child during the test. Also, there are video tapes your child can watch.

    The ECHO enables the cardiologist to obtain valuable information about the heart’s structure and function. In some cases, the ECHO can provide enough accurate information that a cardiac catheterization is not necessary.
  • Exercise (Stress) Test
    Exercise testing determines how the heart works and adjusts to different levels of activity. It is done in a special room equipped with EKG and blood pressure monitoring equipment. A doctor and technologist monitor your child while he walks/runs on a treadmill. To prepare for the stress test, your child should eat a light meal two hours before coming to the hospital and wear comfortable clothing and shoes. He will be encouraged to stay on the treadmill as long as possible. After the test, he may feel tired. The doctor and technologist will continue to monitor your child for several minutes after the test. Most children feel rested after this brief period. When the test is over, your child can eat, drink and resume normal activities, including returning to school.
  • Fetal Echocardiogram
    An echocardiogram performed to look at the heart function of a baby before birth. The fetal echocardiogram is performed by moving the transducer slowly over the expectant mother’s abdomen. This test can be done anytime after the 18th week of pregnancy.
  • Heart Catheterization (Heart Cath)
    A cardiac or heart catheterization or “heart cath” is a minimally invasive procedure which uses thin, flexible tubes called “catheters” to look at and get information about the heart from the inside. To get inside the heart, the catheters are inserted into the big blood vessels in the groin, called the femoral (FEM-or-ul) artery and vein, in the same way an intravenous (IV) line is placed. Sometimes other blood vessels in the neck or arm also are used. The catheters are gently pushed through the blood vessels and into the heart using a type of x-ray called fluoroscopy (floor-OS-co-pee) to guide the placement of the catheters. Once the catheters are in position inside the heart, they can be used to gather different types of information depending on what the doctor needs to know.
  • Holter Monitor
    This portable monitor enables an EKG to be recorded for 24 hours. It is worn by your child at home or school and during sleep. The purpose of the monitor is to determine the heart’s rate and rhythm during normal activities. To attach the monitor, several small stick-on patches are placed on the chest. The recording device, approximately the size of a small transistor radio, is worn on a belt or shoulder strap.

    You also will be given a diary. While your child is wearing the monitor, it is important for you to record any symptoms, change of activity or other unusual events in the diary. This information, along with the EKG pattern, will be studied by the cardiologist to determine how the heart functions during your child’s daily routine.
  • MUGA Scan
    The purpose of this test is to measure the amount of blood pumped out of the heart to the body with each beat. The amount is called an ejection fraction and is described as a percentage. For the test, your child will be given two doses of medicines. The medicines are injected into a vein. Your child will feel a pinching sensation when these injections are given. The remainder of the scan is not painful. Your child will need to lie still on the examination table while a special machine (scanner) makes the necessary measurements. The scanner resembles a large X-ray camera. Smaller children may need sedation to remain still during the test. Occasionally, an exercise MUGA is performed. During this test, the same measurement is made while the child is exercising with special equipment. Parents may remain with their child during a MUGA scan.
  • NMR or MRI
    Nuclear Magnetic Resonance Imaging (NMR or MRI) is a way of producing pictures (scans) of the inside of the body without using X-rays. NMR uses magnetic waves and a computer to create the picture. NMR scans can be used to learn more about the heart structure. The scan is performed in a room with a large doughnut-shaped machine. Your child will be placed on a flat bed that is then moved to the center of the machine. The test is not painful, but there will be noises while the machine is working. Your child will need to lie still during the scan. Young children may need to be sedated. The scan lasts approximately 30-60 minutes. Parents are usually asked to wait in a nearby room. A technologist or nurse will be with your child to explain the procedure and offer comfort.
  • Transesophageal Echocardiogram (TEE)
    This type of echocardiogram is done in a sedated patient by passing a small transducer into the mouth and down the esophagus (the long tube-like structure connecting the mouth to the stomach). The TEE shows the heart and surrounding vessels in greater detail than the traditional ECHO.
  • Ventilation/Quantitative Perfusion Scan (V/Q Scan)
    This test is performed in two parts. First, the child breathes a special gas. The scan determines which areas of the lungs fill with the gas. Second, a substance is injected into the vein that is traced as it goes to the small vessels of the lungs. This defines areas of the lungs receiving blood.