Atrial Flutter vs. Atrial Fibrillation: What Are the Differences (Symptoms, ECG, Causes)?

  • Medical Author:
    Charles Patrick Davis, MD, PhD

    Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

  • Medical Editor: William C. Shiel Jr., MD, FACP, FACR
    William C. Shiel Jr., MD, FACP, FACR

    William C. Shiel Jr., MD, FACP, FACR

    Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

Atrial Fibrillation Facts

What is atrial flutter, and what is atrial fibrillation (definitions)?

Atrial flutter is a type of atrial tachycardia that results in an arrhythmia (rhythm disorder or not a normal rhythm) where the atria of the heart beat too quickly in a fast, usually regular, rhythm.

Atrial fibrillation is another type of atrial tachycardia that is closely related to atrial flutter. However, the arrhythmia that occurs in AFib is much more chaotic and results in a fast and usually very irregular heart rhythm or a atypical and irregular ventricular rate that can effect heart health.

Are atrial flutter, atrial tachycardia, and atrial fibrillation the same thing?

Atrial flutter, atrial fibrillation (AFib), and atrial tachycardia are not the same things. However, all three terms have in common a rapid heart rate that can be felt when a person feels their pulse. Atrial tachycardia is a general term that indicates a cardiac condition where the rate of contraction of the heart's atria is fast and not normal, but does not describe the type of heart rhythm other than fast. Atrial tachycardia's are also termed supraventricular tachycardia's and are a type of cardiac arrhythmia that usually result in a fast heartbeat, even at rest.

In contrast, atrial flutter and AFib are two of the main types of atrial tachycardia. They are distinguished by the different patterns of abnormal electrical impulses generated in the atria; a regular pattern for atrial flutter and an irregular pattern for AFib. Both are considered an abnormal heart rhythm and not good for heart health, and both have the potential to decrease the overall health of the patient.

What are the differences in how atrial flutter and AFib affect the heart (ECG wave strip patterns)?

What does ECG and electrical conduction of a normal heart look like?

Normal Cross Section of the Heart and Electrical Conduction
Normal Cross Section of the Heart and Its Electrical Conduction
ECG of Normal Heart Rhythm
ECG strip of Normal Heart Rhythm

 Atrial flutter ECG

Atrial flutter is a health condition that causes the atria of the heart to have a conduction or electrical problem that result in a re-entry loop in a regular pattern the causes the atria to beat at a rapid rate of about 240-360 beats per minute (bpm). The atrial flutter waves are regular and on an electrocardiogram (ECG, EKG) are seen as P waves in a regular "saw tooth" pattern (small P waves in succession with short or no intervals between each wave). Often, the flutter waves are not completely transferred through the AV node to the ventricular heart chambers so occasionally electrical conduction blocks occur and produce a 2:1, 3:1 or 4:1 ventricular contraction rate that is mainly regular. The most common atrial flutter occurs when the atria beat at a rate of 300 bpm and ventricular contraction rate is 150 bpm (2:1 conduction). Infrequently, some patients with flutter waves may also have bradycardia because the heart's ventricles are not receiving most of the flutter P waves. Flutter waves may come and go spontaneously in some patients. Atrial flutter is the second most common tachyarrhythmia.

ECG sawtooth wave pattern of atrial flutter

ECG Sawtooth Wave Pattern of Atrial Flutter
ECG Strip: Sawtooth Wave Pattern of Atrial Flutter

AFib ECG

Atrial fibrillation is the most common tachyarrhythmia. The incidence is about 27-28 per 1000 person years. AFib is a heart disease that causes the atria of the heart to have a conduction or electrical problem that results in a chaotic, irregular production of irregular QRS waves with no P waves. In contrast to flutter waves, the abnormal conduction creates irregular, rapid occurring QRS waves, some of which are conducted to the heart ventricles through the AV node. This results in the heart having ventricular contractions that are irregular, variable in effective blood pumping and usually range from about 100-175 bpm.

What does ECG and abnormal electrical conduction of atrial fibrillation look like?

ECG of the heart's abnormal electrical problem in AFib

The Misconduction of the Hear'ts Electrical System in AFib

ECG of the Abnormal Conduction of the Hear'ts Electrical System in AFib 

ECG wave pattern of atrial fibrillation
ECG strip showing abnormal wave pattern of atrial fibrillation

Picture of the heart's abnormal electrical conduction in AFib

Picture of the Hear'ts Abnormal Electrical Conduction in AFib
Picture of the Heart's Abnormal Electrical Conduction in AFib

Which heart condition is more serious, atrial flutter or atrial fibrillation?

Both heart diseases have the potential of becoming serious. However, many doctors and other health care professionals consider atrial flutter to be less serious than atrial fibrillation because flutter symptoms tend to be less severe and flutter waves have a less risk of embolization (clot formation). In addition, flutter waves also tend to revert back to sinus rhythm spontaneously more often in some patients.

What's the difference between how these two heart conditions feel (symptoms); can you feel atrial flutter and/or atrial fibrillation?

The difference between atrial flutter and AFib in terms of feeling are very similar. However, if the person can have someone (or even themselves) feel a pulse, if the pulse is regular even though it's fast, the problem is probably atrial flutter. If the pulse is fast and irregular, then the person is more likely to have AFib.

Although some people have no symptoms and cannot feel the arrhythmias, common clinical symptoms of both arrhythmias are:

Serious symptoms may include the following:

Quick GuideAtrial Fibrillation: Heart Symptoms, Diagnosis, & Afib Treatment

Atrial Fibrillation: Heart Symptoms, Diagnosis, & Afib Treatment

What Are the Types of Arrhythmias?

An arrhythmia is an irregular heartbeat, and it can be caused by a variety of processes and problems with the heart, for example, heart disease, injury from a heart attack, or healing after heart surgery. Even people with healthy hearts can have irregular heart rhythms. There are a variety of types of arrhythmias (abnormal heart beat), for example:

  • Premature ventricular contractions or PVCs
  • Atrial fibrillation
  • Atrial flutter
  • Certain types of tachycardias
  • Ventricular fibrillation
  • Long QT syndrome
  • Bradyarrhythmias
  • Heart block

Do the causes and risk factors for atrial flutter and atrial fibrillation differ?

Any damage to the healthy electrical pacemaker in the heart's right atrium or left atrium may result in flutter or fibrillation QRS waves. No one knows for sure what triggers either atrial flutter or AFib. However, many doctors and other health care professionals suggest that the risk factors for these two arrhythmias are essentially the same and function as probable causes of the two heart problems. Unfortunately, there are many risk factors for flutter and fibrillation:

What is the difference between the treatments for atrial flutter and atrial fibrillation?

In general, because these two arrhythmias are similar in their potential causes, the American Heart Association suggests the same treatment guidelines for both AFib and atrial flutter. The goal of any of these treatments is to return the heart to a normal condition, removal of signals to generate the arrhythmias.

In some individuals, vagal maneuvers like bearing down to have a bowel movement or administration of an IV dose of adenosine may stop atrial flutter. They do not work well for treatment or conversion or stoppage of AFib. However, other medications and procedures are virtually identical (dosage may vary) for treatment of flutter and fibrillation according to the American Heart Association. Medications include antidysrhythmics and beta blockers. Anticoagulants are used prevent blood clots (thromboembolic problems).

Procedures include electrical cardioversion, ablation (radio wave ablation, laser ablation, freezing ablation techniques) of abnormal atrial tissue generating electrical impulses and other surgical techniques such as generation of scar formation (Maze procedure) to block or eliminate abnormal P wave or irregular QRS complex formation in some individuals that are refractory to more common treatments.

Can either of these conditions be prevented?

Unfortunately, these two problems are difficult to prevent because there are so many potential causes and risk factors associated with them. Some risk factors you cannot change; for example, age over 60, family members with one of the conditions, and being a white male. However, most organizations like the American Heart Association publish suggestions to reduce risk, which include:

What is the prognosis for someone with atrial fibrillation or atrial flutter?

The prognosis and life expectancy for patients with atrial flutter or atrial fibrillation depends on the patient's underlying condition. Individuals with complicated medical conditions and poor response to medications or procedures have a poorer prognosis. Patients with atrial flutter may have slightly better prognosis than patients with atrial fibrillation. However, patients with either arrhythmia that undergo ablation have an excellent prognosis with a very low recurrence rate. Ablation can allow a patient to have a normal rhythm with a normal ventricular rate (normal heart rate) and a return to normal heart health.

REFERENCES:

American Heart Association. "Prevention Strategies for Atrial Fibrillation (AFib or AF)." Updated: July 2016
<http://www.heart.org/HEARTORG/Conditions/Arrhythmia/AboutArrhythmia/Prevention-Strategies-for-Atrial-Fibrillation-AFib-or-AF_UCM_423784_Article.jsp#.WNLP4OSrOM9>

Last Editorial Review: 3/23/2017

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Reviewed on 3/23/2017
References
REFERENCES:

American Heart Association. "Prevention Strategies for Atrial Fibrillation (AFib or AF)." Updated: July 2016
<http://www.heart.org/HEARTORG/Conditions/Arrhythmia/AboutArrhythmia/Prevention-Strategies-for-Atrial-Fibrillation-AFib-or-AF_UCM_423784_Article.jsp#.WNLP4OSrOM9>

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