Atrial fibrillation (AFib) and atrial flutter are common types of arrhythmias — abnormal heart rhythms. The two conditions share many similarities, and it may be difficult to tell them apart. Both can cause fatigue, heart palpitations, and a risk of stroke. Despite these similarities, they differ in significant ways. While there are overlapping symptoms, causes, diagnoses, and treatments, these can also vary between the two.

What Are Atrial Fibrillation and Atrial Flutter?

Atrial fibrillation and atrial flutter are both abnormally fast heart rhythms. Heart rhythm is driven by electrical impulses of the heart, which affect the heart’s contractions and the movement of blood. In normal heart rate and rhythm, the heart’s chambers beat in a coordinated fashion at a rate of 60 to 100 beats per minute.

The most common type of arrhythmia is atrial fibrillation. AFib can make the top chambers of the heart, the atria, beat up to 350 times per minute. This activity forces the lower chambers of the heart, the ventricles, to beat around 150 beats per minute. In AFib, the heart has trouble pumping blood out of the atria. Instead of beating regularly as they should, the atria quiver or fibrillate (shake), which causes a fast and irregular heartbeat.

Atrial flutter, on the other hand, is an abnormal heart rhythm characterized by a rapid but regular heartbeat. The heart beats with a steady rhythm but at a faster rate than what is considered normal. It usually causes an atrial heartbeat between 250 and 350 beats per minute, and it can still push the ventricles up to 150 beats per minute.

Symptoms of Atrial Flutter and Atrial Fibrillation

Atrial fibrillation and atrial flutter may not have any noticeable symptoms. When they do, the most common symptoms of both include:

• Lightheadedness
• Fainting
• Heart palpitations or fluttering
• Fatigue
• Shortness of breath
• Chest pain

Causes of Atrial Flutter and Atrial Fibrillation

The underlying causes of atrial fibrillation and atrial flutter are similar. Both are usually caused by weakness in or changes to the heart’s cells and tissue. These weaknesses may come from:

• High blood pressure
• Coronary heart disease
• An overactive thyroid gland (hyperthyroidism)
• Heart problems present at birth (congenital heart disorders)
• Heart valve disorders

Aging, genetics, or infections can also damage the heart in a way that triggers AFib.

Risk Factors for Atrial Flutter and Atrial Fibrillation

Risk factors for developing atrial fibrillation and atrial flutter are generally very similar. They include:

• Diabetes
• Thyroid conditions
• High blood pressure
• Other heart conditions
• Lung disease
• Sleep apnea
• Alcohol consumption
• Illicit drug use

Other lifestyle habits, such as smoking tobacco, may also increase the chance of developing AFib or atrial flutter.

One difference between the two conditions is that lung disease is associated with a greater risk of atrial flutter, while chronic (long-term) kidney disease is more often associated with AFib.

Although physical activity usually helps lower the chances of developing AFib, too much intense exercise might raise your risk for this condition. Additionally, stressful situations and emotional strain can contribute to the onset of this disorder. Both AFib and atrial flutter can also be triggered during heart surgery.

Diagnosing Atrial Flutter and Atrial Fibrillation

The diagnosis of both atrial fibrillation and atrial flutter typically involves the use of an electrocardiogram (which you may see abbreviated as either ECG or EKG). An ECG, a common procedure to measure the heart’s electrical activity, can show differences between AFib and atrial flutter.

In atrial flutter, although the heart’s rhythm isn’t at a normal speed, it beats at regular intervals. An ECG for atrial fibrillation would show irregularly spaced heartbeats.

Assessing atrial fibrillation and atrial flutter may also involve a physical examination, a review of your family’s medical history, and any other health conditions you have. Your doctor may also conduct blood tests to check levels of certain electrolytes or thyroid hormones.

Further assessment of AFib and atrial flutter may also involve MRI and echocardiography to get more information about the heart. MRI uses a large magnet to provide information about the heart’s structure, while echocardiography uses sound waves to produce a detailed picture of the heart. This comparison helps doctors understand how well the heart is pumping and check for any blockages or enlarged areas — a sign of damage.

If your doctor suspects atrial flutter, a lung function test might also help confirm the diagnosis.

Treating Atrial Flutter and Atrial Fibrillation

Treatment options for atrial fibrillation and atrial flutter are similar. They may include medical procedures or medications. Your cardiologist or another doctor will help you understand which options might be best for you.

Procedures

Common procedures for both atrial fibrillation and atrial flutter include:

• Electrical cardioversion — Low-energy shocks are delivered to the heart to restart a normal heart rhythm.
• Catheter ablation — This minimally invasive procedure removes any tissue causing the persistent arrhythmia.

Less commonly, your cardiologist may recommend a pacemaker or implantable cardioverter defibrillator. When other irregular heartbeats are happening alongside AFib and atrial flutter, these devices can help bring the heart rate and rhythm back to normal.

Medications

Many of the same types of medications are used to treat atrial flutter and AFib:

• Beta-blockers help slow heart rate.
• Calcium channel blockers also help control heart rate and may be an option for those who cannot take beta-blockers.
• Anticoagulants, or blood thinners, are used to reduce the risk of blood clots. These medications are particularly important for reducing stroke risk in AFib and atrial flutter.
• Antiarrhythmic drugs are used to control heart rhythm.

The particular drugs your doctor prescribes will be determined by your health condition, symptoms, and other factors.

Lifestyle Changes

Lifestyle changes are usually recommended along with treatments for atrial fibrillation and atrial flutter. Your doctor may recommend that you:

• Manage stress.
• Stay physically active.
• Avoid alcohol, stimulants, and smoking.
• Eat a heart-healthy diet.

These lifestyle changes, when combined with appropriate medications and procedures, can help with better management of atrial fibrillation and atrial flutter.

Can You Have Both Atrial Fibrillation and Atrial Flutter?

It’s not unusual to have both atrial fibrillation and atrial flutter, although they don’t typically occur at the same time. However, your heart is not always in a state of atrial fibrillation or atrial flutter, and while you may experience both, they would not happen at the same time.

An episode of atrial flutter can trigger atrial fibrillation, which can happen during heart surgery and also at other times. Additionally, some antiarrhythmic medications commonly used for AFib management can trigger atrial flutter. These medications help control abnormal heart rhythms. They work to keep the heart's rhythm steady and regular, preventing it from beating too fast or irregularly.

Talk With Others Who Understand

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