Comparing Atrial Flutter vs. Atrial Fibrillation

Atrial flutter and atrial fibrillation (A-fib) are both heart arrhythmias. These conditions cause problems with the way your heart beats. They affect the electrical signals that help your heart beat at a normal rate and rhythm.

Atrial flutter and A-fib force your atria (the upper chambers of your heart) to contract and push blood into the bottom chambers (ventricles) faster. In atrial flutter, the atria beat at a faster but normal rate. In A-fib, the atria beat at a faster but chaotic rate.

Both problems increase your risk of stroke. While they have common symptoms, atrial flutter is less common than A-fib.

This article describes how atrial flutter and A-fib differ and how they are the same. It includes symptoms, causes, treatment, and long-term outlook.

Atrial Flutter vs. Atrial Fibrillation: Arrhythmia Differences

Atrial flutter vs. A-fib arrhythmia differences involve the way they impact your normal heart rhythm, as follows:

• Atrial flutter produces a fast, usually regular rhythm. This involves a “short-circuiting” of the normal electrical impulse in a loop that revolves around the upper chambers of your heart. This interferes with your heart’s ability to maintain a normal resting heart rate of 60–100 beats per minute. It makes the atria beat quickly, up to as many as 300 times per minute, and flutter rather than fully squeezing to empty blood into the lower chambers. This new, fast rhythm can also cause your ventricles to beat too fast, reaching up to 100–200 beats per minute in a reaction called atrial flutter with RVR (rapid ventricular response).
• A-fib produces a fast though very irregular heart rhythm. A-fib does not follow a set loop because its rhythm is more disorganized and irregular. Instead of contracting, the upper chambers fibrillate, or quiver and shake. Your heart may also switch from beating too fast to beating slowly or even skipping beats.

Your healthcare team can identify the arrhythmia differences between atrial flutter and A-fib in an electrocardiogram (ECG or EKG). This noninvasive medical test is used to evaluate your heart’s electrical system:

Atrial flutter must be identified using an ECG because it is the only diagnostic tool that can pick up atrial flutter’s regular “flutter waves.” These waves produce a sawtooth pattern showing atrial activation. In typical cases of atrial flutter, the atrial rate is around 300 beats per minute, with a ventricular rate of about 150 beats per minute.

With A-fib, an ECG shows no “P” waves, which precede atrial contraction and irregular or random QRS complexes (which indicate normal heart rhythm). Instead of P waves, the ECG shows several small waves of differing sizes called “f” waves, or fibrillatory waves. These f waves represent up to 600 stimuli per minute that occur in the atria during an episode of A-fib.

Asymptomatic Clues and Symptoms

Asymptomatic atrial flutter can occur even if you have an abnormal heart rate. People with no symptoms or only minor symptoms of atrial flutter often have a controlled heart rate that seems to be working as it should.

Asymptomatic A-fib is common in about 33% of people with this condition. There are no symptoms in these cases, and the problem may only be detected during a physical examination or testing for another condition.

Research indicates that asymptomatic A-fib is associated with the following characteristics:

• Male gender
• Older age
• Previous myocardial infarction (heart attack)
• Limited physical activity
• Comorbidities (co-occurring conditions), including chronic kidney disease and chronic heart failure
• Previous stroke

Symptoms of atrial flutter are often similar to those experienced in A-fib. When they occur, these symptoms include the following:

Causes

Identifying the cause of atrial flutter or A-fib is not always possible. In some cases, it is the result of damage to your heart’s electrical system from the following conditions:

In some cases, damage to your heart tissue can contribute to changes in your heart’s electrical system. These changes can include the following:

• Aging
• Infection
• Fibrosis (thickening or scarring of tissue)
• Inflammation
• Stretching, thinning, or thickening of your heart walls
• A buildup of protein, cells, or minerals in your heart tissue
• Reduced blood flow to your heart

Atrial Flutter Leading to Atrial Fibrillation

When comparing atrial flutter vs. A-fib, atrial flutter is considered a less severe heart condition than A-fib. However, without treatment, people with atrial flutter can develop A-fib as their heart weakens from the stress of beating too fast for too long. Research indicates A-fib rarely develops without being preceded by atrial flutter.

In some people, atrial flutter coexists with A-fib (alternating from one to the other). In a study of adult patients in Finland with atrial flutter and atrial fibrillation, the following was reported:

• 80% of those diagnosed with atrial flutter also had A-fib
• 20% of those diagnosed with A-fib patients also had atrial flutter

Treatment Differences Between Atrial Flutter vs. Fibrillation

While there are some treatment differences between atrial flutter vs. fibrillation, the goals of treating these conditions include the following:

• Controlling your heart rate
• Restoring the normal rhythm of your heart rate
• Preventing blood clots to reduce your risk of stroke

Factors such as your age, your level of fitness, and other medical conditions are used to create a personalized plan of treatment. This can be achieved through the use of medication, devices, and/or surgery.

Medications

Medication can be used to prevent blood clots, slow your heart rate, or restore your heart’s normal rhythm. The following drugs are commonly used:

Beta-blockers: These medications slow the rate at which your lower heart chambers pump blood through your body:

• Coreg (carvedilol)
• Inderal LA (propranolol)
• Tenormin (atenolol)
• Toprol XL (metoprolol)
• Zebeta or Ziac (bisoprolol)

Anticoagulants: These drugs, also known as blood thinners, prevent blood clot formation or treat an existing blood clot. Drugs in this category include the following:

• Eliquis (apixaban)
• Pradaxa (dabigatran)
• Savaysa (edoxaban)
• Xarelto (rivaroxaban)
• Durlaza (aspirin)

Calcium channel blockers: These drugs can slow your heart rate and reduce the strength of your heart muscle contractions:

• Cardizem (diltiazem)
• Verelan (verapamil)

Antiarrhythmics: These medications work to restore and maintain normal heart rhythm by slowing down the electrical signal that causes atrial flutter or A-fib:

• Betapace (sotalol)
• Cordarone (amiodarone)
• Multaq (dronedarone)
• Rythmol (propafenone)
• Tikosyn (dofetilide)
• Tambocor (flecainide)

Catheter ablation: Catheter ablation, also known as radiofrequency ablation, is effective in curing more than 90% of typical atrial flutter and up to 70% of people with A-fib.

This minimally invasive procedure uses thin electrodes that are threaded up the large veins in your groin. The electrodes deliver radiofrequency, cryotherapy, or laser energy to stimulate your heart so your medical team can locate the source of abnormal electrical tissue causing your arrhythmias.

When the defective area of heart tissue is found, the electrodes deliver radiofrequency energy to make a controlled “burn” inside your heart. This destroys the heart muscle cells at the source of the problem and restores normal heart rhythm.

External cardioversion: External cardioversion is the delivery of high-energy shocks through defibrillator pads attached to your chest. For some people, this effect can also be achieved using medication.

Internal cardioversion: Internal cardioversion is infrequently used. It is the delivery of a low-energy electrical shock internally in your heart. It is administered using two catheters inserted in a vein in your groin to your heart and a small electrode pad applied to your chest. Internal cardioversion is typically used when external cardioversion and medications have failed to return your heart rhythm to normal.

Long-Term Management and Outlook

Your experience with atrial flutter or A-fib is affected by the severity of your condition, whether it occurs as an intermittent or constant problem, and characteristics such as your age and other health conditions.

Lifestyle changes can support the long-term management of these conditions and promote heart health. Lifestyle modifications include the following:

• Establish and maintain a healthy weight.
• Quit smoking if you smoke.
• Manage blood pressure and cholesterol levels.
• Take all medications as directed.
• Stay active by exercising 150 minutes weekly, according to recommendations from the American Heart Association, with approval from your healthcare provider.
• Limit or avoid alcohol or other stimulants.
• Practice active relaxation techniques and manage stress.
• Update your diet to include fewer processed foods, limited amounts of salt, and more fresh fruits and vegetables.
• Control blood glucose if you have diabetes.
• Control sleep apnea (if applicable).

Early diagnosis and treatment can help control your heart rate and rhythm, prevent blood clots, reduce your risk of complications, and help you lead a normal life.

Generally, the following outcomes are typical for these conditions:

Atrial Flutter

Atrial flutter is typically less severe and not life-threatening in its early stages. It also poses a lower stroke risk than A-fib.

However, atrial flutter should not be ignored. Over time, atrial flutter can weaken your heart muscle, leading to the following problems:

• Stroke
• Heart failure (a condition in which your heart can’t produce enough blood for your body’s needs)
• Chronic fatigue
• Other heart rhythm problems like A-fib
• Inconsistent blood supply

For most people with atrial flutter, catheter ablation can be curative. If the condition is not cured, medications can often manage your condition.

Atrial Fibrillation

Without treatment, disease progression can make the problem more serious. People with A-fib generally have a 4 times increased risk of mortality (death) compared to people in the general population.

However, most people do not die from A-fib but instead succumb to complications of the condition. The problems that contribute to the highest mortality rates include stroke, heart disease, and heart failure.

Summary

Atrial flutter and A-fib are conditions that cause problems with the way your heart beats. They trigger messages that prevent your heart from having a normal heart rate. While atrial flutter can be cured, A-fib remains a lifelong issue.

These problems are linked because atrial flutter often precedes A-fib. Some people have both problems at the same time. As a result, they involve many of the same symptoms and treatments.

Early diagnosis and treatment are the best ways to prevent long-term problems and disease progress. Since both problems can occur without symptoms, talk to your healthcare provider about your risk of having atrial flutter or A-fib and whether testing is advised.