Preparing for an EP study
You will need to provide your doctor with your medical history including:
- Medications, vitamins and supplements you are currently taking, especially any medicines that affect blood clotting (you will need to stop taking these a few days before the procedure)
- Any conditions you may have, especially bleeding disorders
- Allergies to any medications or substances, if any
Depending on your existing health conditions, you may be asked to undergo some tests to confirm you are healthy enough to undergo the procedure. You will also need to fast, usually overnight, before the procedure.
During an EP study
Just before you begin, you may be given a sedative and a local anaesthetic to numb the pain of the catheter insertion. If it is being inserted through the vein in the groin, the area may need to be shaved.
You will also be connected to an electrocardiogram (ECG) monitor via small electrodes attached to your skin – this will help to monitor your heart’s activity during the EP study.
Next, the catheter will be inserted. Fluoroscopy, a form of X-ray, is used to help doctors guide the catheter to the right side of your heart. Once it is in position, your doctor will test different areas of the heart using small electrical impulses. During this time, you may feel your heart beat strong and faster than usual. If an abnormal heart rhythm is triggered, you may feel lightheaded and dizzy.
Depending on what the EP study reveals, the doctor may then provide medication or issue an electrical shock to stop the arrhythmia. In some cases, an ablation may be performed to remove the tissue that is causing the irregular heartbeat.
If you feel pain in your chest, neck, jaw, arm or back, or have difficulty breathing, tell your doctor immediately.
After an EP study
After the EP study is done, the catheter is removed and a bandage applied to stop the bleeding. Your condition and recovery will be observed and if the catheter was inserted via the groin, you won’t be able to move your leg for several hours.
You will be told when you can get out of bed. Be careful to move slowly at first to avoid dizziness. Your doctor will advise when you are ready to be discharged.
Take care to avoid strenuous activities for a few days, and follow your doctor’s advice on when you can resume normal activity.
Once at home, take note of any sign of bleeding, unusual pain, swelling, and abnormal colour or fever. A small bruise is normal but if there is a large amount of blood, especially if it won’t stop after applying pressure, contact your doctor immediately.
You should also call your doctor if you experience any of these:
- Fever with a temperature higher than 38°C
- Increased pain, redness, swelling, or bleeding or other drainage where the catheter was inserted
- Coolness, numbness or tingling, or other changes in the affected leg
- Chest pain or pressure, nausea or vomiting, profuse sweating, dizziness, or fainting
Risks of an EP study
Possible complications of an electrophysiological (EP) study include:
- Bleeding and bruising at the site where the catheter is put into a vein
- Damage to the vessel that the catheter is put into
- Formation of blood clots at the end of the catheter(s) that break off and travel into a blood vessel
Rarely, infection or damage to the heart or its electrical system may occur.
Any current health condition may also affect your risk, so be sure to discuss your medical history and any concerns beforehand.