What is an electrophysiological study?
An electrophysiological study (EP study) is a procedure used to evaluate abnormal heartbeats.
Natural electrical impulses coordinate contractions of the different parts of the heart. This helps keep blood flowing the way it should. This movement of the heart creates the heartbeat, or heart rhythm.
During an EP study, small, thin wire electrodes are put into a vein in the groin (or neck, in some cases). The wire electrodes are threaded through the vein and into the heart, using a special type of X-ray “movie,” called fluoroscopy. Once in the heart, the heart’s electrical signals are picked up by the electrodes and measured. Electrical signals are also sent through the electrodes to stimulate the heart tissue to try to cause the abnormal heart rhythm so that it can be evaluated and its cause can be found, or to help evaluate how well a drug is working.
During the EP study, doctors may also map the spread of the heart’s electrical impulses during each beat. This may be done to help locate the source of an abnormal heart beat. If a location is found, the tissue can be destroyed.
The results of the EP study may also help the doctor decide whether more treatment is needed and which treatment would be best. You may need a pacemaker or implantable defibrillator, adding or changing medications, doing more ablation procedures, or providing other treatments.
What are the risks of an electrophysiological study?
Possible risks of an electrophysiological study (EP study) include:
- Severe rhythm problems
- Bleeding and bruising at the site where the catheter(s) 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 of the catheter site(s)
- Rarely, perforation (a hole) of the heart
You may want to ask your doctor about the amount of radiation used during fluoroscopy and the risks related to your situation. It is a good idea to keep a record of your radiation exposure, such as previous scans and other types of X-rays, so that you can inform your doctor. Risks associated with radiation exposure may be related to the cumulative number of X-rays and/or treatments over time.
For some people, having to lie still on the procedure table for the length of the study may be uncomfortable or painful.
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.
What happens after an electrophysiological study?
In the hospital
After the procedure, you may be taken to the recovery room for observation or returned to your hospital room. You will stay flat in bed for several hours after the procedure. A nurse will monitor your vital signs, the insertion site, and circulation/sensation in the affected leg or arm.
You should let your nurse know right away if you feel any chest pain or tightness, or any other pain, as well as any feelings of warmth, bleeding, or pain at the insertion site.
Bed rest may vary from 2 to 6 hours depending on your specific condition.
In some cases, the sheath or introducer may be left in the insertion site. If so, you will be on bed rest until the sheath is removed. After the sheath is removed, you may be given a light meal.
After the specified period of bed rest, you may get out of bed. The nurse will help you the first time you get up, and may check your blood pressure while you are lying in bed, sitting, and standing. You should move slowly when getting up from the bed to avoid any dizziness from the long period of bed rest.
You may be given pain medication for pain or discomfort related to the insertion site or having to lie flat and still for a prolonged period.
You may go back to your usual diet after the procedure, unless your doctor tells you otherwise.
When you have recovered, you may be discharged to your home unless your doctor decides otherwise. If this procedure was done on an outpatient basis, you must have another person drive you home.
Once at home, you should check the insertion site for bleeding, unusual pain, swelling, and abnormal discoloration or temperature change. A small bruise is normal. If you notice a constant or large amount of blood at the site that can’t be contained with a small dressing and stopped by putting pressure over the area, contact your doctor right away.
It will be important to keep the insertion site clean and dry. Your doctor will give you specific bathing instructions.
You may be advised not to participate in any strenuous activities for a few days after the procedure. Your doctor will tell you when you can return to work and go back to your normal activities.
Contact your doctor if you have any of the following:
- Fever and/or chills
- Increased pain, redness, swelling, or bleeding or other drainage where the catheter was inserted
- Coolness, numbness and/or tingling, or other changes in the affected leg
- Chest pain/pressure, nausea and/or vomiting, profuse sweating, dizziness, and/or fainting
Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.