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:

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:

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.