What You Can Expect During the Study
You will be awake during the procedure; although medication may be given to help you relax (it's not uncommon to doze off during the procedure). The staff will be monitoring your progress constantly.
The EP study usually is not painful, although you may feel some pressure at the insertion site(s) during the insertion of the electrode catheters. There also may be some discomfort from lying still for a long time. You will not feel the catheters moving through the blood vessels and into your heart.
During the procedure, doctors may stimulate your heart with tiny electrical impulses. You will not feel these impulses, but they may induce the arrhythmia that has caused your symptoms in the past. Let the staff know if you feel lightheadedness, palpitations, chest pain or shortness of breath.
An arrhythmia induced in the EP lab will often stop by itself. If an arrhythmia persists, especially if it is very rapid, it may cause you to faint for a moment. If this occurs, the staff may deliver an electric shock to your heart to restore a normal rhythm.
Outside of the EP lab, such arrhythmias could be dangerous and even life-threatening. In the EP lab, however, well-trained personnel have the equipment and medications to handle these arrhythmias.
The procedure can be quite lengthy. Depending on the particular arrhythmia you have and the findings, a complete study can last from two to six hours.
Is the EP Study Safe?
An EP study is an "invasive" procedure that requires the insertion of catheters into the body. It therefore involves some risk. The risk is small, however, and the EP study is considered relatively safe.
Some patients may develop bleeding at the insertion site. Blood collects under the skin, resulting in local swelling and/or a "bruise" in the groin or arm.
Less frequently, EP studies may be associated with more serious complications. These include damage to the heart or blood vessels, formation of blood clots, and infection. Deaths are very rare.
Although most patients who undergo EP studies do not experience complications, you should be aware of the risk. To learn about your particular risk, you should discuss the matter with the doctor.
The EP study and catheter ablation are very similar procedures. In fact, your doctor may decide to do both procedures, one after the other, while you are in the EP lab. This possibility will be discussed with you prior to the study.
Catheter ablation is a non-surgical technique that destroys parts of the abnormal electrical pathway that is causing your rapid heart rhythm.
During catheter ablation, doctors insert a special electrode catheter into the heart. They position the catheter so that it lies close to the abnormal electrical pathway and then pass radiofrequency (heat) energy through it. The tip of the catheter heats up and destroys (ablates) the small area of the heart tissue that contains the abnormal pathway.
After the EP Study
After the procedure is completed and the catheters are removed, the doctor (or nurse) will apply firm pressure to the insertion site(s) for about 20 minutes. This is done to prevent bleeding. If the insertion site was in the arm, the doctor may close the incision with a few stitches.
You will be transported to your room or the recovery area. Whether you are allowed to eat or drink soon after the study depends on your condition.
Back in your room, you will lie flat in bed for two to four hours (occasionally longer), to allow a small seal to form over the puncture in the blood vessel. During that time, do not bend or lift the leg where the catheters were inserted. To relieve stiffness, you may move your foot or wiggle your toes.
The nurse will check your pulse and blood pressure frequently and will also keep checking the site(s) where the catheters were inserted. If you feel sudden pain at the site or if you notice bleeding, notify the nurse immediately.
The doctor who performed the study may be able to discuss some of the test findings with you soon after the procedure. A complete, detailed analysis of all of the measurements will take more time.
Depending upon the results of the study, you may be sent home after several hours of observation, or the next day. When it's time to go home, have a friend or family member drive you.
At Home, After Your EP Study
Limit your activity during the first 24 hours after you return home. You can move about but do not strain or lift heavy objects.
If you notice new blood on the dressing, place your fingers over the site and press firmly for about 20 minutes. If bleeding continues, call your doctor or go to the nearest emergency room while continuing to apply pressure.
Leave the dressing on the insertion site(s) until the day after the procedure. The nurse will tell you how to take it off and when it is okay to take a shower.
A bruise or a small lump under the skin at the insertion site is common. They generally disappear within three to four weeks.
Call your doctor or nurse if the insertion site becomes painful or warm to touch, the bruising or swelling increases, or you develop a fever over 100F.
Call your doctor if you have recurrence of your rapid heart rhythm, or if you experience dizziness, chest pain or shortness of breath.
Be sure to check with your doctor or nurse about medications - which ones to continue, and which ones to stop.
What Happens Next?
The decision about what to do next will depend on the type of arrhythmia you have, the severity of your symptoms and the results of the various diagnostic tests, including the EP study.
Your doctor will decide if your arrhythmia requires treatment and if so, which option is best for you.
Antiarrhythmic drugs work by changing the electrical signals within the heart. By doing so, they help prevent abnormal sites in the heart from starting rapid or irregular heart rhythms.
If you need medication for the arrhythmia, it is important to make sure the medication is working properly. Therefore, after two or more days with the medication in the hospital, you may be brought back to the EP lab for a follow-up study. The goal is to find the medication that works best for your particular arrhythmia.
An artificial pacemaker is a device that's implanted inside the body, ready to pace the heart. It is used for treating markedly slow heart rhythms.
The pacemaker is usually implanted beneath the skin, just below the collarbone. It senses the person's heartbeat and responds accordingly. If it senses that the heart beats too slowly or pauses for too long, the pacemaker sends tiny electrical signals which stimulate the heart to contract and pump blood.
An implantable cardioverter-defibrillator (ICD) is a device that is implanted inside the body, ready to deliver an electrical shock to the heart. ICD's are most often used in people who have had life-threatening rapid heart rhythms.
ICDs are larger than pacemakers and are generally implanted beneath the skin and muscle of the abdomen or chest. The device continuously monitors the heart rhythm. If it senses a serious rapid heart rhythm, it delivers one or more electric shocks to the heart and restores a normal rhythm.
Catheter ablation, as we've seen, is a non-surgical technique that destroys parts of the abnormal pathway that's causing the arrhythmia. It is used for treating rapid heart rhythms.