Tests

Electrophysiology Study (EP Study):

An EP study is an accurate method for studying the heart’s electrical system.  It allows doctors to find abnormal sites inside the heart that may be causing serious arrhythmias.  During an EP study, doctors insert special electrode catheters into the heart.  These catheters can sense electrical activity in different parts of the heart.  They can also be used to deliver tiny electrical impulses to pace the heart.

 

Why Do an EP Study?

If basic tests such as electrocardiograms and holter machines do not provide the doctor with sufficient information, you may be a candidate for an EP study.  The EP study provides the most detailed and accurate information about how your heart’s electrical system is working.

In general, the EP study is done for one or more of the following reasons:

• To diagnose the cause of your symptoms, such as lightheadedness, dizziness, palpitations, or fainting.
• To pinpoint the location of a known arrhythmia and decide the best treatment.
• To see how well certain medications are working.
• To see how severe an arrhythmia is and predict the risk of a future cardiac event.
• To decide whether you need an implantable device, such as a pacemaker or defibrillator, or a treatment procedure such as an ablation.

 

Pre-test Guidelines

You will be asked not to eat or drink anything for 6 to 8 hours before your study.  This helps prevent nausea.  You may take small sips of water to take your medications. 

Check with your doctor several days before your EP study.  Sometimes, you will be asked to stop some medications for 2 to 3 three days before the test. 

Make arrangements with a friend or family member to drive you to the hospital.  You will not be allowed to drive home after the procedure since you may be sedated.

Tell the doctor or nurses if you have had any reactions to medications or anesthesia in the past, or if you have a history of bleeding problems.

Because the EP study may take up to a few hours, please be sure to empty your bladder before the procedure.  In some cases a urinary catheter may be inserted to drain your bladder

What to Expect

Unless you are already in the hospital, you will be asked to arrive in the morning on the day of the EP study, or perhaps the night before.  You may have several routine tests before the procedure such as an ECG, x-rays, and blood tests (these may also be done a few days before the procedure). 

The doctor will talk with you about the test and its purpose, benefits, and risks.  This is a good time to ask questions and address any concerns you may have.  You will then be asked to sign a consent form implying that you have agreed to the risks and benefits. 

A nurse will shave and clean the area where the catheters will be inserted.  This is usually at the groin, in the fold between the thigh and the abdomen.  In some cases it may be at the arm, shoulder, or neck.  Shaving and cleansing makes it easier to insert the catheters and help prevent infections. 

An intravenous (IV) line will be inserted into a vein in your arm.  This line allows drugs to be injected directly into the vein, if they are needed.  To help you relax, you will be given a sedative.

The special electrode catheters used during the EP study are long, flexible wires that carry electrical impulses to and from the heart.  One or more catheters are inserted into the body and moved toward the heart, while the staff watches their progress on a television screen.  The catheters are then put in place inside the heart chambers. 

Electrode catheters sense electrical activity in areas of the heart and measure how fast those impulses travel.  Electrode catheters can also be used to deliver tiny electrical impulses to pace the heart.  By pacing the heart, doctors can induce certain arrhythmias so they can be watched in the EP lab.  An EP study can take anywhere for 1 to 4 hours.

The results of the EP study can help your doctor decide which treatment would be best for you. 

Holter Monitor:

A holter monitor is a device that is used to monitor the heart and records its rhythm.  A holter device is usually worn for 24 hours while the patient performs their usual daily activities.  The device uses 3 to 7 electrodes that attach to the patients chest.  Wires from the electrodes attach to the small battery-operated device that can be slipped onto the waist.

Patients keep a diary of their activities, such as sleeping or eating, so that physicians can associate any arrhythmia with a specific activity. During Holter monitor testing, patients should avoid taking showers or baths and limit the use of small electrical devices, such as electric toothbrushes or razors.

Electrocardiogram (ECG or EKG):

An electrocardiogram is a simple test that records the electrical activity of your heart.  The heart’s electrical impulses cause a needle to trace the heartbeat as a wavy line on a sheet of paper.  By examining the sequence of events on the tracing, doctors are able to diagnose arrhythmias. 

Echocardiogram:

This exam is used to examine the muscle motion and circulation of the heart.  This is done with an ultrasound, the ultrasound images will show the movement of the blood in each chamber and as it passes through the valve.  The heart walls and chambers are measured for size.  The approximate time for this examine is 30 minutes.  There is no preparation necessary for this exam. 

Stress Echocardiogram:

This exam compares resting and exercising ultrasound images of your heart (circulation) and simultaneous EKG recordings (electrical).  This exam takes about one hour.  This exam is essentially the same whether done on a bicycle or on a treadmill. 
           
During the test:

You will be asked to change into a gown and the technologist will hook you up to an EKG monitor, which will stay on during the entire test, and two resting EKG’s will be taken immediately

You will then have an ultrasound of your heart to examine the heart muscle, heart valves, and overall heart function.

You will then be asked to exercise on a treadmill for 6 to 10 minutes.  When your peak exercise is reached you will stop exercising and another ultrasound of the heart will be obtained.

Comparisons will be made of both heart images and the EKG to complete the exam.  Please wear tennis shoes or comfortable walking.  Exercise testing results are best done when you have not eaten for one hour before the exam.  Medications can be taken as usual. 

Tilt-Table Study:

Tilt table testing helps determine how the body responds to changes in body position.  It is used for patients who have had syncope (fainting spells).  Before doing the test the patient may be asked to fast the day of or day prior to the test.

The patient lies on a table that can be moved to a nearly upright position while the heart rate, blood pressure, and symptoms are monitored.  The patient is monitored using an electrocardiogram while lying down.  The patient is strapped down the table lying flat and then the table is tilted to an almost completely upright position.  The majority of the time, the patient is suspended sixty to eighty degrees.  The patient is instructed not to move.  Symptoms, blood pressure, pulse, electrocardiogram, and oxygen saturation are recorded.

The test ends when the patient faints or has other significant symptoms, or after a set period of time which usually ranges from 20-45 minutes.