This page describes a non-surgical procedure known as an electrophysiology study. You will also read the term catheter ablation, a procedure that may be performed depending on the results of the test electrophysiology study. If you or a family member have additional questions, please feel free to ask your doctor or nurse at any time.

The purpose of an electrophysiology study

Your doctor has recommended that you have an electrophysiology (EP) study because you have cardiac arrhythmia. The purpose of the test is to cause your heart to produce the arrhythmia in the controlled environment of the Electrophysiology Lab so that your cardiologist can locate and diagnose the cause of your arrhythmia.

Once the test has been completed and a diagnosis has been made, your doctor may recommend specific treatment options: medication, surgery, an implantable cardioverter defibrillator (ICD), and a pacemaker or catheter ablation.

Pre-testing instructions:

Do not eat or drink after midnight the day of the procedure and until the procedure is completed.

Take all medications as prescribed with a small sip of water unless directed otherwise by your doctor. Be sure to tell your doctor if:

• You have an allergy to seafood, x-ray dye or iodine.
• You know or suspect that you are pregnant.
• You are taking blood thinners.
• You have a history of bleeding problems.
• You are diabetic.

The electrophysiology procedure

You will be awake during the entire EP study, you should try to remain quiet and still throughout the procedure. You will wear a hospital gown, and you may wear your glasses, hearing aid and dentures. This is a sterile procedure. To limit the chance of infection and to maintain a sterile field, you will be covered with sterile cloths from neck to feet. To limit movement and to be sure your hands do not enter the sterile field, your wrists may be strapped to the examination table.

At the start of the procedure, a nurse will give you a sedative to help you relax. If you don't already have an intravenous needle (IV), one will be started. A bladder catheter may also be started. Your blood pressure and electrocardiogram (ECG) will be monitored throughout the procedure.

The procedure begins by administration of an anesthetic in the groin area. You may feel a slight "stinging" sensation during the injection. During the procedure, the doctor will insert two plastic tubes, called sheaths, into a vein and an artery in the groin. Then, a thin, flexible tube (catheter) is carefully guided into your heart. The doctor will follow the progress of the catheter through the veins while watching the procedure on an x-ray. Since blood vessels do not have nerves, you should experience no pain while the catheter is threaded into your heart.

Once the catheters are in place, the doctor will use them to artificially stimulate or start your arrhythmia. You may be kept in this state for a length of time. The doctor may also start and stop the arrhythmia by using drugs to control it. Because the doctor will start your arrhythmia, you will experience the same feelings you do when the arrhythmia occurs naturally. Your doctor can stop the arrhythmia immediately if necessary. If it is necessary to stop the arrhythmia by applying a shock to the heart, you will receive medication to make you comfortable. You will be unable to feel the shock that is administered.

How long does the EP study take?

The procedure usually takes 1-3 hours. It is unusual to experience any pain during the procedure. Report any pain or discomfort to your doctor immediately.

If catheter ablation is recommended, the procedure will probably be performed immediately while you are in the EP lab. Catheter ablation uses high-frequency sound waves to eliminate the tissue that is responsible for causing the abnormal heart rhythm. Following the ablation, these cells will cease to function, thus eliminating the cause for the abnormal heart rhythm. The catheter ablation procedure may be applied a number of times during the same procedure. Catheter ablation takes 2-6 hours.

After the procedure, catheters will be withdrawn and pressure will be applied to the catheter insertion sites.

Complications

Complications following catheter ablations are rare, but complications do occur and may include: injury to or bleeding in a blood vessel, blood clots developing inside the heart or blood vessels that hold the catheters, stroke, bleeding in the sack surrounding the heart or implanting of a permanent pacemaker. To reduce the risk of blood clots or stroke, blood-thinning medication may be given during the procedure. The doctors and nursing staff are highly skilled and are prepared to act immediately in the event of any complication.

What to expect following the EP study

After the EP study, you will be transferred to the recovery room or to the Coronary Care Unit where you will be closely monitored by the nursing staff. The catheters will be removed from your groin. There will be no stitches. A sterile dressing will be placed on the wound. This can be removed the next day. It is important to keep your leg as still as possible to help the catheter insertion site heal. Your doctor will decide when you will be able to eat and drink after the test. You will remain in bed for 4-6 hours, with the head of the bed either flat or slightly raised to allow the insertion site to heal.

Your blood pressure, heart rate, breathing and catheter insertion site will be closely monitored by your nurse. The IV will remain in place for 2-3 hours and the nurse may place a small weight on the catheter insertion site to apply pressure to prevent bleeding. It is not uncommon to have swelling, bruising and a small lump at the catheter insertion site. The nurse will help you use the bedpan or urinal if you need it. Please tell your nurse if you experience any pain or discomfort including warmth, wetness, and numbness or tingling.

If you have had a catheter ablation, you will spend the night in the hospital so that your heart rhythm can be monitored. Your doctor will determine what medications you will receive and when you will be able to drink liquids and eat solid food.

Homegoing instructions

• Avoid heavy activity for 7 days, including pushing or pulling heavy objects or lifting more than 10 pounds.
• Stop exercising before you become tired or short of breath. If you experience chest pain during exercise, stop immediately.
• Call your doctor and follow all instructions given. If you cannot reach your doctor and are still in pain, call 911.
• Keep all follow-up appointments with your doctor.
• You may return to your normal sexual activity after your groin heals.
• Don't smoke.
• Plan a diet that is healthy, tastes good and is low in fat and cholesterol. Too much weight is hard on your heart and blood vessels. If you need to lose weight, ask your doctor for help.
• Learn to manage stress. Discuss any emotional problems you may have with your doctor or nurse.
• Avoid rubbing the lump where the catheter was inserted.
• When you can return to work depends on the kind of work you do. Your doctor will discuss with you when you can return to work and when you can start driving again.

Call your doctor if:

• Your arm or leg becomes numb or painful, or if there is redness or a yellow discharge.
• You have pain or numbness below the catheter insertion site (leg, toes, arm, and fingers).
• The catheter insertion site swells or bleeds. If this happens, lie down immediately on a firm surface and have someone apply pressure to the catheter insertion site for 10 minutes by pressing the heels of both hands over the lump and pushing down. If the swelling and/or bleeding does not stop, call your doctor or go to the emergency room while continuing to hold pressure on the site.

Medications