The vital test that helps detect abnormal heart rhythms

When your heart isn’t ticking the way it should, you need to find out why. Normally, the heart beats at a steady rhythm, or between 60 and 100 times per minute when you’re at rest. If you have a heart arrhythmia, however, it could beat too quickly (tachycardia), too slowly (bradycardia) or in an irregular pattern.

Some abnormal heart rhythms need treatment because they can be dangerous, or in certain cases, deadly. An electrophysiology study (EPS) can determine if you have a heart rhythm disorder and what kind it is. This special arrhythmia test helps doctors decide the best way to reset your out-of-sync heart.

The basics of cardiac arrhythmias

Your heart’s electrical system controls the rate and rhythm of its four chambers: two upper atria and two lower ventricles. Electrical impulses normally start in the right atrium and flow through pathways in the heart. This creates coordinated, steady beats. Bad signaling anywhere along this route can cause an issue with your heart rhythm. Some problems trigger obvious arrhythmia symptoms, including a fluttering sensation or pounding in your chest, dizziness or shortness of breath, but other heart rhythm problems may go unnoticed.   

Before an EPS, doctors use tests, such as electrocardiograms and heart monitors, to look for a suspected arrhythmia. But sometimes those tests can’t pick up irregular heartbeats, as arrhythmias can be unpredictable; your heart may beat normally most of the time but then fall out of rhythm periodically. Sometimes an arrhythmia is detected, but doctors can’t tell exactly where the problem starts in your heart.

Who gets an EPS?

An EPS can rule out or confirm an arrhythmia and pinpoint the spot where your electrical system is going haywire. Your doctor may order one if you:

• Have a known arrhythmia: Your doctor may want to get a closer look at how electricity flows through your heart to make better treatment decisions.
• ​Are at increased risk of sudden cardiac death: Certain heart problems make it more likely that you could go into cardiac arrest. This is when your heart stops and is a situation that requires immediate emergency care.  An EPS can help doctors understand your personal risk for cardiac arrest and how to prevent it from happening.
• Lose consciousness: Sudden fainting spells (known as syncope) can be a big red flag for an arrhythmia.
• Are getting a cardiac catheter ablation: An EPS is done before this procedure, which uses heat or cold to destroy small areas of the heart to block bad electrical signals.

Your doctor may strongly suspect that you have a rhythm problem and order an EPS if you have stubborn symptoms that aren’t explained by other health problems. These include:

• Heart palpitations, which can feel like a flutter, a skipped beat or a racing heartbeat
• Dizziness or light-headedness
• Weakness or fatigue
• Pounding in the chest
• Shortness of breath

If you are concerned about heart symptoms, it’s important to get the care you need. Learn more about the heart care services we offer or find a doctor near you. 

How is an EPS done?

Electrophysiology studies are invasive, meaning they occur inside your body. The test is done in a high-tech hospital laboratory under the close supervision of electrophysiologists and a team of specialists.

You may be awake during the procedure but given medication to make you relax and feel comfortable. If your doctor plans to perform an ablation as well, you may be given general anesthesia.

During the test, several catheters (narrow, flexible tubes) are inserted into a vein usually in your groin. The catheters have electrodes on the tip and are carefully guided into various areas of your heart. The medical team sees continuous live images on a video screen.

The electrodes record your heart’s electrical activity. The electrophysiologist uses small electrical impulses to slow down or speed up heartbeats, hoping to trigger a suspected arrhythmia. This “pacing” technique can unmask what kind of arrhythmia you have and the exact tissue responsible.

An arrhythmia triggered during the procedure will either resolve on its own, or the electrophysiologist will use drugs, more pacing or other techniques to get your heart back into rhythm.

An EPS usually takes several hours. You’ll have to lie still in recovery for a few more hours as your small puncture wound starts to heal.

What happens next?

If you’re diagnosed with a heart rhythm disorder, your treatment will depend on what type you have, your symptoms or if you’re at risk for major complications. Types of heart rhythm disorders include: 

Ventricular arrhythmias — arrhythmias that begin in the heart’s ventricles — often described as a "skipped beat." These are usually harmless unless they're very frequent or you have heart disease. 

Treatments for ventricular arrhythmias may include all or some of the following:

• Medications that control the rate and rhythm of your heart
• Cardiac catheter ablation
• A device called an implantable cardioverter defibrillator, which can detect a fast or erratic heartbeat and shock the heart back into rhythm
• Healthy lifestyle adjustments, such as being more active, maintaining a healthy weight, easing stress and not smoking

Supraventricular arrhythmias — arrhythmias that begin in the atria, or the heart’s upper chambers — which can cause troubling symptoms like fatigue and shortness of breath. 

The most common arrhythmia, atrial fibrillation (A-Fib), is a fast and irregular heartbeat that occurs when the atria fibrillate (quiver) so blood can’t move as effectively into the ventricles. As a result, blood clots can form and move from the heart to the brain. 

Treatment is often one or more of the following:

• Blood thinners to prevent clots
• Medications that control the rate and rhythm of your heart
• Electrical cardioversion (low voltage electric shock) to restore a normal heartbeat
• ​Cardiac catheter ablation
• Surgery to disrupt abnormal electrical signals or to implant a pacemaker to restore the heart’s natural rate and rhythm

Your doctor may ask you about all the medicines you take because some can trigger arrhythmias. Your lifestyle matters too. Heart disease, high blood pressure, electrolyte imbalances, drinking too much caffeine or alcohol or using certain illegal drugs can also trigger an irregular heart rhythm.

Bottom line: If you have a suspected arrhythmia, your doctor may refer you to a specialist, called a cardiac electrophysiologist, who can map your heart’s electrical system and determine if you have an irregular heartbeat and how it should be managed.  

If you think you may have a heart arrhythmia, make an appointment with your physician to evaluate your symptoms and determine the best treatment option for you. Find a doctor near you. 

HCA Healthcare's collaboration with the American Heart Association

Knowledge and management of heart-related risk factors and conditions are critical to improving overall health and preventing disease. This is the focus of
the American Heart Association’s Getting to the Heart of Stroke™ initiative, developed in conjunction with HCA Healthcare and the HCA Healthcare Foundation. The initiative includes a new stroke self-management tool, along with an emphasis on greater engagement with patients diagnosed with atrial fibrillation (A-Fib) through the Association’s MyAFibExperience patient support network.