When your heart’s normal, steady rhythm is disrupted and starts beating abnormally fast, slow, or in an irregular pattern, doctors call this condition an arrhythmia.

There are several arrhythmia types. Some are temporary or relatively harmless. Others can lead to potentially severe complications if they’re not treated.

This article will look at the different types of arrhythmias, what causes them, and how they’re typically treated.

The rhythm of your heart is established by electrical impulses that follow the same route in and around your heart. These impulses begin in the sinoatrial (SA) node at the top of your heart. They then move through a network of fibers to all the chambers of your heart.

This electrical pattern allows your heart’s chambers to pump out blood and then relax and fill with blood in a controlled sequence. It keeps blood flowing steadily throughout your body.

Some heart rhythm changes are expected and even healthy, such as a faster heart rate during exercise. An arrhythmia, on the other hand, is any change to your heart’s electrical activity that causes an abnormal or unpredictable pattern of heartbeats.

You may notice a change in your heart rate when you have an arrhythmia, but in many cases, other symptoms are more obvious. While symptoms can vary from one type of arrhythmia to another, some common symptoms of a heart rhythm disturbance include:

  • palpitations
  • chest pain or a feeling of tightness in the chest
  • dizziness or lightheadedness, or almost fainting
  • fatigue
  • anxiety
  • shortness of breath or exercise intolerance

The three main types of arrhythmias include:

  • supraventricular arrhythmias
  • ventricular arrhythmias
  • bradyarrhythmias

Arrhythmias are classified by where they originate or how they affect the heart’s electrical system. Let’s look at these three main types in more detail.

Supraventricular arrhythmias

A supraventricular arrhythmia originates in the upper chambers of the heart, called the atria. Some examples include:

Atrial fibrillation

One of the most common types of arrhythmia, atrial fibrillation (AFib) occurs when the atria quiver rather than contract and relax in time with the ventricles. It affects regular circulation and significantly increases the risk of blood clots forming within the atria.

Atrial flutter

In the case of atrial flutter, the atria beat much faster than the ventricles. But unlike AFib, which has an irregular heartbeat, atrial flutter usually presents with a steady but abnormally rapid rhythm.

However, just as AFib can cause blood clots to form in the heart and potentially cause a stroke, atrial flutter can also interfere with blood flow and allow clots to develop in the heart’s upper chambers.

Paroxysmal supraventricular tachycardia (PSVT)

Most types of arrhythmia are more common in older adults and people with other heart issues. However, PSVT can occur in children and people with no heart health issues.

PSVT is characterized by a rapid heart rate from a disturbance with the electrical impulses that travel from the top of the heart to the ventricles. These arrhythmias can occur during vigorous exercise. They may last for just a few seconds or minutes.

Premature atrial contractions (PACs)

If your heart’s electrical system triggers an early beat, it can cause an extra heartbeat. When it originates in the upper chambers of your heart, it’s known as premature atrial contraction (PAC).

This type of arrhythmia is common among adults. It may feel as if your heart has skipped a beat. Treatment is usually not needed.

Ventricular arrhythmias

A ventricular arrhythmia originates in the heart’s lower chambers, called the ventricles. These are among the most serious heart rhythm disturbances. They include:

Ventricular tachycardia

When a very fast heartbeat starts in the ventricles, the condition is known as ventricular tachycardia (V-tach).

Symptoms of V-tach, such as a racing heart and chest pain, are sometimes more obvious than symptoms of other types of arrhythmia. It’s also among the most dangerous arrhythmias, especially for people with heart disease.

Ventricular fibrillation

Ventricular fibrillation refers to a condition in which the ventricles beat weakly and not in their usual steady manner.

Ventricular fibrillation is the most life threatening arrhythmia. The heart is not effectively beating and a person can go into cardiac arrest. Cardiac arrest is an often-fatal event in which the heart stops suddenly.

Premature ventricular contractions (PVCs)

A PVC is a much less serious type of arrhythmia than the two mentioned above. It’s caused by your heart’s electrical system that triggers an early or extra beat that originates in the ventricles.

This type of arrhythmia doesn’t usually need treatment unless it happens very frequently.

Bradyarrhythmias

Some types of arrhythmia can cause the heart to beat slower than normal. Two of the most common types of bradyarrhythmias are:

  • Heart block: a blockage or interference with the electrical impulses moving toward the ventricles
  • Sinus node dysfunction: a problem with the SA node

Even though the heart’s electrical system is usually durable enough to keep going day after day for many years, it’s still vulnerable to a variety of threats.

These threats include other heart-related problems and various medical conditions that seem unrelated to the heart, such as COVID-19.

Some of the most common triggers for an arrhythmia include:

Because feelings of stress and anxiety are often associated with a racing heart or a heart flutter, it’s natural to wonder whether those emotions can actually cause an arrhythmia.

Studies have produced conflicting results. A 2020 review of earlier research suggests that emotional issues, such as work stress or anxiety, do not affect atrial fibrillation risk.

However, a 2019 study suggests that anxiety may be a risk factor for atrial fibrillation.

What does seem clear is that even if stress doesn’t actually trigger the onset of an arrhythmia, it can lead to more frequent episodes and worsening symptoms. Stress can also cause behaviors (such as alcohol use) that are associated with arrhythmias.

To diagnose an arrhythmia, a doctor will review your symptoms and medical history. If a heart rhythm problem is suspected, a doctor may have you undergo one or more of the following tests:

  • Ambulatory monitor. An ambulatory arrhythmia monitor is a wearable device that measures and records your heart rate 24 hours a day.
  • Electrocardiogram (EKG). An EKG is often the primary test that’s used to diagnose arrhythmia. It involves a healthcare professional placing electrodes on your chest, arms, and legs to record your heart’s electrical activity. An EKG gives a snapshot of your heart at that moment in time.
  • Echocardiogram. An echocardiogram uses sound waves to create images of your heart. This can help diagnose heart-related issues, such as valve disease, that may be causing an arrhythmia.
  • Electrophysiologic study. With electrophysiologic study, a doctor guides a thin, flexible catheter from a blood vessel in your leg up to your heart to determine the heart’s electrical map.

An undiagnosed arrhythmia may increase your risk of serious complications, including a stroke, cardiac arrest, or heart failure. It may also lead to a reduced quality of life due to fatigue and other symptoms.

If you suspect you may have an arrhythmia, visit a doctor if you experience:

Arrhythmias are usually treatable conditions. Depending on the type and severity of your arrhythmia, a combination of treatments may be needed. Typical treatments include:

  • anti-arrhythmic drugs to help stabilize your heart rate
  • blood thinners to help prevent blood clot formation
  • catheter ablation, which uses a catheter to deliver a high frequency charge to destroy the small section of heart tissue suspected of causing the arrhythmia
  • electrical cardioversion, a procedure in which a doctor delivers an electrical impulse to the heart from outside the chest to try to reset the rhythm
  • implantable cardioverter defibrillator (ICD), a small battery-powered device surgically placed in the chest and wired to the heart with electrical leads that can transmit electrical energy when an arrhythmia is detected

Though often treatable, an arrhythmia may require a lifetime of care by a cardiologist. Talk with your healthcare team about what level of care is right for you and the type of arrhythmia you have.

Even if you’re getting treatment for an arrhythmia or have had a procedure to treat it, you will still need to adopt a heart-healthy lifestyle that includes:

  • Regular exercise. It’s important to exercise regularly under the supervision of your doctor, cardiologist, or cardiac rehabilitation specialist.
  • A heart-healthy diet. Follow an eating plan that supports your heart health, such as the Mediterranean diet.
  • Not smoking. If you smoke, talk with your doctor about how to quit and manage withdrawal symptoms and cravings.
  • Stress management. A 2016 study suggests that stress management may help reduce the frequency of ventricular and supraventricular arrhythmias while also boosting quality of life. Consider adopting healthy stress management techniques such as:

When electrical changes within your heart cause it to beat abnormally, it’s known as an arrhythmia. Certain types of arrhythmias result from events such as a heart attack or infection. Others develop without obvious origins.

A rapid heart rate that isn’t accompanied by stress or physical exertion, for example, is one type of arrhythmia. The same is true for an unusually slow heart rate. An arrhythmia may also take the form of a quivering heart rate or heartbeats that follow no set pattern.

Tests that record your heart’s electrical activity can help a doctor diagnose the type of arrhythmia you have and determine the best treatment option.

Once your doctor confirms the diagnosis and prescribes a treatment plan, adopting heart-healthy behaviors can help manage the condition and reduce the risk for complications down the road.