What is the doctor looking for?
With this test, the doctor is studying the electrical function of your heart. Arrhythmias can be very dangerous and, sometimes, life threatening. While most arrhythmias are treatable, the treatment will be based on the cause. That is why your doctors have decided that you need an electrophysiology study of your heart.
What is the test?
“Electrophysiology” is composed of two words: The first part of the word, electro, means electrical, and the second part of the word, physiology, means function. When the electrical conduction system in the heart is changed, an abnormal heart rhythm - called arrhythmias - can develop. Often the aging process or a previous heart attack is the cause, but arrhythmias can also occur in young, healthy people. You will lie on your back on a table. Every effort will be made to see that you are comfortable. EKG patches will be placed on your chest to monitor your heart rhythm. You will be covered with a sheet. A large X-ray camera will be positioned over your chest and will be used to help position the catheters during the procedure.
Your skin will be scrubbed and your hair shaved from potential catheter insertion sites. The scrub provides a clean insertion site and reduces the chance for infection. The most commonly used catheter insertion site is the groin, although the arm is occasionally used.
Inserting the catheters
Catheters are long, thin flexible wires that can be threaded through a blood vessel leading to your heart. Two catheters usually are used, but, depending on the type of study to be performed, as many as four can be used. Before the catheters are inserted, the insertion site will be scrubbed with an antiseptic solution. The staff will wear gowns, masks and gloves when working with the catheters. These precautions are taken to protect you from infection. Placement of the catheters should not cause any significant pain. Before inserting the catheters, the area will be numbed with a medication. You will feel a needle stick, but after that you should feel only pressure while the catheters are being positioned. After the catheters are in place you will probably not be aware that they are there.
Recording and pacing
During the EP study, the catheters are moved to different locations in the heart and electrical activity is recorded. The catheters are also used to control how fast your heart beats and to add extra beats. This is called “pacing” our heart. You may be unaware of this pacing or you may feel your heart speed up, slow down or skip a beat. If an arrhythmia starts, you may feel some of the same symptoms that caused you to seek medical attention. Please tell the EP staff what you feel. Let them know if you have shortness of breath, dizziness, light-headedness or chest discomfort. You may be given some medications during the procedure. Some drugs are given to imitate the response of your body to stress and activity. Some drugs are given to prevent arrhythmias from occurring. If the arrhythmia causes severe symptoms, it will be stopped immediately. If the arrhythmia does not stop on its own, it may be stopped by the same pacing impulse that started it. Occasionally, the arrhythmia must be stopped by an electrical shock applied to the chest. This is called a cardioversion. After the test, the catheters will be removed. Firm pressure will be applied over the insertion site for about 15 minutes to prevent any bleeding from the insertion site. You will then be taken back to your room.
You will need to rest flat in bed for 2-8 hours after the study. During that time it is important to keep the arm or leg used in the procedure straight to prevent bleeding from the insertion site. After the specified amount of bed rest, you will be able to resume your previous activity level.
Your nurse will be in your room frequently during the first hour after the study to take your blood pressure, heart rate and check your insertion site for signs of bleeding. The pulses and temperature of your feet will also be checked. You will be instructed to apply pressure firmly to the insertion site if you cough or sneeze and while using the bedpan or urinal. If you should notice any bleeding at the site, notify your nurse immediately. If your back becomes uncomfortable, do not hesitate to ask the nurse for pain medication.
Eating and drinking
You will be able to resume your previous diet and your nurse will help you, if necessary, eat while you are flat in bed.
Where are the tests done?
The EP study is done in a special procedure room. This room is similar to an operating room and contains electronic equipment to be used during the EP study.
May I eat or drink?
You will be asked not to eat or drink anything for 8 hours prior to the test. If your test is not scheduled until later in the day, you may have a liquid breakfast after which you must not eat or drink.
What about medications?
Check with your physician about your current medications. You may be asked to stop taking some of your medications for a few days before your test.
Will I have an IV?
A small intravenous (IV) catheter will be placed in a vein in your hand or arm. This may be used to continuously administer fluids or it may be capped with a heparin lock for intermittent use. Special monitors will be used to provide a continuous reading of your heart rhythm.
Do I need special clothing?
What should I bring to the test?
Be sure to bring all your medications with you. You should wear the hospital gown provided to you without bottoms. Use the bathroom just before going to the lab because it will be several hours before you return to your room.
How long does the test take?
An initial EP study usually takes 1 -1 /2 hours. Your family members can wait in your room or in the visitors lounge. They will be notified when you return to your room.
When will the results be ready?
The results will be available immediately, but a typed report will be prepared within 24 hours.
Tell your doctor/nurse if you have …
Any allergies or if you are taking Coumadin. Also, be sure to tell your doctor if you are pregnant as this will affect the procedure.
Will the test make me sick or sleepy?
You will not receive anything to put you to sleep before the EP study. It will be important for you to describe any sensations you may have during the test to the doctors in the EP laboratory.
Will I receive any radiation during the procedure?
What if I am pregnant or breast-feeding?
Inform your doctor as this may alter the procedure.