Echocardiogram/EKG

Several drugs used to treat CNS tumors can damage the muscle of the heart, decreas-
ing its ability to contract effectively. Many protocols require a baseline echocardiogram
to measure the heart’s ability to pump before any chemotherapy drugs are given.
Echocardiograms are then given periodically during and after treatment to check for
heart muscle damage.
An echocardiogram uses ultrasound waves to measure the amount of blood that leaves
the heart each time it contracts. This percentage (blood ejected during a contraction
compared to blood in the heart when it is relaxed) is called the ejection fraction.
A technician, nurse, or doctor administers the echocardiogram. The child or teen lies
on a table and has conductive jelly applied to the chest. Then the technician puts a
transducer (which emits the ultrasound waves) on the jelly and moves the device
around on the chest to obtain different views of the heart. Pressure is applied on the
transducer and can sometimes cause discomfort. The test results are displayed on
videotape and photographed for later interpretation.
Meagan used to watch a video during the echocardiogram. Sometimes
she would eat a sucker or a Popsicle. She found it to be boring, not
painful.
An EKG (electrocardiogram) measures the electrical impulses that the heart gener-
ates during the cardiac cycle. Prior to placing the electrodes, the technician will clean
the area with alcohol and will apply a cool gel under the electrodes. The test is per-
formed at the bedside, in the cardiologist’s office or in the cardiac clinic or lab. Your
child must lie quietly during the test and you may remain with him throughout the
procedure, which generally takes less than ten minutes. Your child will feel nothing
during the procedure other than the gel on the electrodes.