What is an Electrophysiologist? What They Do, When to See One, and What to Expect

Written by WebMD Editorial Contributors

• What Does an Electrophysiologist Do?
• Education and Training
• Reasons to See an Electrophysiologist
• What to Expect at the Electrophysiologist

In the United States, heart disease is the leading cause of death for most racial and ethnic groups, contributing to about a fourth of US deaths every year. Every 40 seconds, someone in the US has a heart attack. 

While a cardiologist is equipped to deal with most cardiovascular disease, sometimes the input of a cardiovascular subspecialist is required. Electrophysiology is one such subspecialty.

An electrophysiologist, also known as a cardiac electrophysiologist or cardiac EP, is a cardiologist who focuses on testing for and treating problems involving irregular heart rhythms, also known as arrhythmias. They examine your heart’s electrical system, which sends an electrical signal through your cells in order to regulate heart rate and rhythm.

Electrophysiologists generally work at a larger cardiac practice or hospital where they test for, diagnose, and treat abnormal heart rhythms. They are trained in the use of highly specialized tests, devices, and procedures in order to do so. They also may prescribe medication or make lifestyle recommendations. 

An electrophysiologist may diagnose and treat conditions such as:

• Bradycardia. A heartbeat that is too slow.
• Tachycardia. A heartbeat that is too fast. There are three main types, according to where the problem originates in the heart.
• Atrial Fibrillation. A quivery, fluttery heartbeat.
• Cardiac Arrest. The sudden stop of your heartbeat.
• Other arrhythmias and heart disorders.

Electrophysiologists are cardiologists who have further training in the specialty of electrophysiology. After getting their bachelor’s degree, they go through a process that involves completing:

• An average of four years in medical school
• A three-year residency in internal medicine
• Three to five years additional training in cardiovascular disease fellowship(s)
• An exam to become certified as a cardiologist by the American Board of Internal Medicine or the Advisory Board for Osteopathic Specialists of the American Osteopathic Association
• Two years additional training in electrophysiology 
• An exam to become certified as an electrophysiologist by the American Board of Internal Medicine

Your primary care doctor or another cardiologist may refer you to an electrophysiologist if you:

• Have an abnormal heart rhythm
• Are undergoing or being considered for cardiac ablation, a procedure that creates scar tissue in order to block erratic signals
• Experience syncope, i. e., a sudden loss of consciousness
• Have a risk of sudden cardiac death
• Are undergoing heart surgery
• Might benefit from a pacemaker or implantable cardiac defibrillator (ICD)

Electrophysiologists are generally seen by referral and not through direct appointment.

Electrophysiology studies (EPS) test the electrical activity of your heart in order to locate sources of arrhythmia. The doctor will insert a thin tube called an electrode catheter into a blood vessel that leads to your heart. This insertion is usually in the groin but may be in the arm or neck. They will then send electrical signals to your heart and record its activity.

Electrophysiology studies usually take place in a specialized laboratory within a clinic or hospital. This room may be called the electrophysiology laboratory (or EP lab) or the catheterization laboratory (or cath lab). The test should last about 1-4 hours.

Before undergoing EPS, you should:

• Not eat or drink anything for 6-8 hours before
• Tell your doctor about any supplements or medications you take and follow their instructions
• Have someone drive you to your appointment and take you home

The doctor will then review your test results and make recommendations for your course of treatment.  

What They Treat, Training, and More

An electrocardiologist, also known as a cardiac electrophysiologist, is a cardiologist who specializes in the electrical system of the heart.

These doctors receive the same education and training as a cardiologist, as well as additional training to diagnose and treat heart arrhythmias and cardiac rhythm disorders.

An abnormal heart rhythm, also known as an arrhythmia, occurs when there’s a problem with the electrical impulses that coordinate heartbeats.

Some heart arrhythmias don’t cause symptoms, so it’s possible to have one and not realize it until a routine physical examination. An electrocardiologist can determine what type of arrhythmia you have, and then recommend a treatment based on the diagnosis.

Common causes of an irregular heartbeat include:

1. Atrial fibrillation

Also known as AFib, this is when the upper chambers in the heart beat out of coordination with the lower chambers. This is a common cause of an irregular heartbeat, according to the American Heart Association. AFib can cause:

• heart palpitations
• fatigue
• dizziness
• shortness of breath
• chest pain

If left untreated, there’s the risk of blood clots and stroke. This condition can also weaken the heart and lead to heart failure.

2. Bradycardia

This is when the heart beats too slowly, fewer than 60 beats per minutes (bpm). Symptoms can include:

• fainting
• dizziness
• fatigue
• shortness of breath
• chest pain

3. Tachycardia

This is when the heart beats too fast, at a resting heart rate of more than 100 bpm. Supraventricular tachycardia originates in the top chambers of the heart, whereas ventricular tachycardia originates in the lower chambers of the heart.

Ventricular fibrillation is another type of tachycardia, which is rapid fluttering of the heart muscles. This prevents blood from properly pumping to the body. If left untreated, an extremely fast heart rate could cause heart failure, stroke, or cardiac arrest.

4. Sudden cardiac arrest

This is when the heart unexpectedly stops beating due to a change in heart rhythm. This can occur in people with or without heart disease.

5. Long QT syndrome

This refers to a fast, chaotic heart rate that can cause fainting, seizures, and sudden death. With this condition, an abnormality in the electrical system of your heart means it takes longer for your heart muscles to recharge between beats.

6. Wolff-Parkinson-White syndrome

Wolff-Parkinson-White syndrome is a rare congenital heart disorder where extra electrical pathways in your heart trigger an abnormal heartbeat. Symptoms include heart palpitations, breathing difficulty, lightheadedness, and chest pain.

Some heart arrhythmias and heart rhythm disorders aren’t caused by an underlying medical problem. Irregular heartbeats can also occur during pregnancy, or as a side effect of a medication, which your electrocardiologist can determine.

Since an electrocardiologist is also a cardiologist, these doctors have the same education requirements — about 10 years of training after completion of an undergraduate degree.

This includes four years of medical school, three years of general internal medicine education, also called a residency, and three years of specialized training in cardiovascular diseases.

A cardiologist can continue their education to become an electrocardiologist. If so, they’ll complete an extra two years of training to become board-certified in clinical cardiac electrophysiology.

The main difference between an electrocardiologist and a cardiologist is the level of training each doctor receives, and their main areas of expertise.

Electrocardiologists sub-specialize in electrophysiology. This medical specialty delves into the study and treatment of heart rhythm disorders. This is their primary area of expertise.

Cardiologists also receive some education and training in electrophysiology, but only about a year.

Your primary care doctor may detect an irregular heartbeat on a physical exam. You’ll likely receive a referral to an electrocardiologist for testing.

Some heart arrhythmias don’t cause symptoms. When symptoms do occur, they include:

• dizziness
• fluttering in the heart
• chest pain
• lightheadedness
• sweating
• fainting
• fatigue

See a doctor if you experience any of these symptoms, especially if you have risk factors for arrhythmia, such as:

• high blood pressure
• diabetes
• sleep apnea
• heart disease
• thyroid disease

Understanding the underlying cause of a heart arrhythmia involves undergoing one or more tests. Your electrocardiologist will ask about your medical history, family history, and symptoms. Tests to diagnose the cause of an abnormal heart rhythm include:

• Electrocardiogram (ECG or EKG). This test records the electrical activity of your heart at rest.
• Echocardiogram. This test uses sound waves to create images of the heart. It can assess your heart’s:
  • shape
  • size
  • function
  • structure
• Holt monitor. You’ll wear a portable ECG for a couple of days. It records your heart rhythm as you complete everyday tasks.
• Event monitor. Some people have arrhythmias that come and go. With this test, you’ll have a portable device attached to your body for about a month. You’ll activate this device whenever you experience symptoms of an irregular heartbeat.
• Stress test. You’ll ride a stationary bike or run on a treadmill while your doctor monitors the electrical activity of your heart. This can help determine whether exercise induces arrhythmias.
• Tilt table test. You’ll lie on a table that moves at different angles. This test helps diagnose the underlying cause of fainting spells. Your doctor monitors your heart rate and blood pressure as the table tilts in various directions.

Heart arrhythmias can be dangerous and life-threatening if left untreated. An electrocardiologist, however, has the training and expertise to diagnose an irregular heart rhythm and recommend treatment.

See a doctor if you experience any symptoms of a heart arrhythmia. These symptoms include chest pain, lightheadedness, or heart palpitations. Electrocardiologists specialize in diagnosing these conditions.

You may receive a referral to an electrocardiologist from your healthcare provider or you can use an online search tool to find an electrocardiologist in your area.

Read this article in Spanish.

Hereditary diseases of the cardiovascular system in questions and answers

What are the symptoms of hereditary heart disease?

Some people with hereditary heart disease have no symptoms, while others experience symptoms such as:

• dizziness
• palpitations
• fainting
• irregular breathing

For many families, the first sign that something is wrong is when a family member dies suddenly for no apparent reason.

What are the different types of hereditary heart disease?

The most common hereditary heart diseases are cardiomyopathies and channelopathies, as well as disorders of cholesterol metabolism.

Hereditary cardiomyopathies can cause malfunction of the heart muscle:

• hypertrophic cardiomyopathy – local or widespread thickening of the wall predominantly of the left ventricle of the heart;
• dilated cardiomyopathy – thinning of the muscular wall of the heart and an increase in the size of the chambers of the heart;
• arrhythmogenic cardiomyopathy of the right ventricle – a change in the wall of the right ventricle, which can lead to the development of life-threatening cardiac arrhythmias.

Channelopathies can cause heart rhythm disturbances:

• long QT syndrome, short QT syndrome and Brugada syndrome – changes in the work of channels in the cells of the heart, which lead to changes in the ECG and life-threatening cardiac arrhythmias;
• catecholaminergic polymorphic ventricular tachycardia – the occurrence of ventricular tachycardia as a result of physical exertion or severe emotional stress;
• progressive conduction disorder – slowing or cessation of the conduction of an electrical signal in the muscle of the heart, which may require the implantation of a pacemaker.

Hereditary conditions that increase the risk of cardiovascular disease include familial hypercholesterolemia – a very high level of cholesterol, which leads to the early development of atherosclerosis of the heart vessels and, as a result, myocardial infarction.

What causes hereditary heart disease?

Genes influence how we look and how our bodies work. Genes act like recipes for making certain things in the body, and each recipe is unique based on the order of the units it is made up of. If there is an error in one of these genes (confusion in the order of these units), it can cause a disease. This error is known as a “breakage” of the gene or a mutation.

As a general rule, if one of your parents has a “breakdown” in the gene, then the chance that you will also have such a “breakdown” is 50%, but there are other scenarios that your doctor will tell you about. It is important to remember that we cannot control which genes we pass on to our children.

Sometimes a person has a “breakdown” in a gene, and any signs or symptoms of the disease itself may never appear. It is important to remember that in this case, a person can still pass on the “breakage” of the gene to their child, and it will be impossible to know how this can affect him.

Most inherited heart diseases show significant variation in symptoms among family members. For example, one person in a family may have a severe illness while another in the same family may only have very mild symptoms.

How to find a mutation (“breakdown”) in a gene?

DNA “breakdowns” that cause health problems are often referred to as mutations.

“Breakdowns” in the structure of genes are detected using genetic testing. Genetic testing allows us to examine your DNA to look for any differences that may predispose you to developing certain health problems.

Genetic testing is available for most hereditary heart conditions. Its goal is to find the “breakage” in a person’s DNA that caused heart disease.

Sometimes, even after a cardiac examination has been performed, it is not clear whether a person has risks related to the heart and what condition the heart is in (because there may be hidden problems that are not visible with conventional examination methods). In some cases, the doctor still has doubts and he refers the patient for genetic testing. These doubts may be dictated by family history, indications in the patient’s history (for example, sensations of palpitations during exercise), minor deviations, or threshold values ​​​​in relation to the norm of a number of indicators. If there are several such thresholds and they are specific for the risk of developing certain diseases or syndromes, this may alert the specialist. There are other reasons as well. In these cases, genetic testing can help answer the specialist’s questions and guide the clinician in the clinical search for the correct diagnosis. Examining a patient to look for genetic causes of hereditary heart disease can provide the doctor with several types of information. In many cases, the results of a genetic test do not change a patient’s diagnosis or treatment, but in some cases, genetic testing can help determine the correct diagnosis and treatment. Also, genetic testing helps to find out which members of your family may be at risk of developing the same heart problem, as well as provide a basis for medical genetic counseling of the family when planning the birth of other children.

What genetic tests can be offered to a patient with hereditary heart disease?

Currently, the most optimal genetic test for patients with hereditary heart disease is DNA sequencing (from Latin sequentum – sequence, determination of the sequence of structural units of the DNA molecule – nucleotides): sequencing of a set of individual human genes or all of its genes (exome sequencing). In some cases, the most comprehensive test is needed – genome sequencing, which includes not only genes, but also intergenic DNA regions. Your doctor will help you decide which test to take. Some families may be offered “trio” sequencing of exomes or genomes (genetic testing of the patient and both parents) or rarer genetic tests: chromosomal microarray analysis, MLPA, etc. In this case, the doctor will explain why there is a need for extended or non-standard genetic testing.

There are three options for the results of genetic testing:

The probability of this or that result is different for different hereditary heart diseases. Ask your doctor what result he expects to get as a result of genetic testing.

The obtained “raw” data of such testing (the so-called FASTQ files) should preferably be taken from the laboratory immediately after receiving the results and stored on electronic media for life. The genetic information contained in this file is very valuable and you and your child may need more during their lifetime.

What to do when a family member is diagnosed with a hereditary heart disease?

If you are a relative of a person who has been diagnosed with a hereditary heart disease, it is recommended that you contact a specialized center. Your doctor, having received this information, will advise you to conduct such studies as are required to confirm or rule out such pathological conditions in you. For example, you may be asked to undergo an electrocardiographic examination, an echocardiogram, a stress test, and help determine which family members are recommended for testing, including genetic testing.

What genetic tests can be offered to relatives of a patient with hereditary heart disease?

As a rule, the relatives of the patient are offered to perform Sanger sequencing of the “breakage” of the gene (mutation) identified in the patient. This is a relatively cheap, simple and quick study of a short DNA segment, which confirms the presence or absence of a gene “breakage” in the first patient (or proband) in the patient’s (or proband’s) family.

In this case, two options for the results of a genetic test are possible:

• Fault found. The relative should be followed up by a specialist.