Atrial Flutter


Article Author:
Mary Rodriguez Ziccardi


Article Editor:
Christopher Maani


Editors In Chief:
Ron Feller
Grant Goold
Kyle Cohen


Managing Editors:
Orawan Chaigasame
Carrie Smith
Abdul Waheed
Frank Smeeks
Kristina Soman-Faulkner
Benjamin Eovaldi
Radia Jamil
Sobhan Daneshfar
Saad Nazir
William Gossman
Pritesh Sheth
Hassam Zulfiqar
Navid Mahabadi
Steve Bhimji
John Shell
Matthew Varacallo
Ahmad Malik
Mark Pellegrini
James Hughes
Beata Beatty
Hajira Basit
Phillip Hynes


Updated:
4/20/2019 8:28:18 PM

Introduction

Supraventricular arrhythmias are a diverse group of atrial arrhythmias. Atrial fibrillation and atrial flutter are the most common of these atrial arrhythmias, and the other less common supraventricular arrhythmias are atrial tachycardias, atrioventricular reentrant tachycardia, atrioventricular nodal tachycardia, and others.

In this review will summarize the management of atrial flutter.

Atrial flutter is one of the most common arrhythmias and is characterized by an abnormal cardiac rhythm that is fast with an atrial rate of 300beats/min and a ventricular rate that can be fixed or be variable that can cause palpitations, fatigue, syncope, and embolic phenomenon.[1]

Atrial flutter is a macro-reentrant tachycardia and depending on the site of origin can be typical or atypical atrial flutter.[1] Electrocardiographic findings of atrial flutter are flutter waves without an isoelectric line in between QRS complex. Electrical axis of the flutter waves can help to determine the origin of the atrial flutter.

Typical or cavotricuspid isthmus (CTI) dependent is the most common type of atrial flutter; this rhythm originates in the right atrium at the level of the tricuspid valve annulus. Typical atrial flutter is seen in the electrocardiogram as continuous negative modulation in inferior leads (II, III, and AVF) and flat atrial deflections in leads I and aVL; this is due to the way of propagation and activation of the macro-reentrant circuit as will be described in the pathophysiology section. 

The atypical atrial flutter is independent of the CTI, and the origin of the arrhythmia can be in the right atrium or the left atrium.

Less commonly, atrial activation can be in a clockwise fashion, and thus electrocardiographic appearance is different, one is unable to differentiate it easily from not isthmus-dependent atrial flutter.

Etiology

The etiology behind atrial flutter is the presence of a re-entry mechanism for initiation of the tachycardia.

To have this electrical circuit, one must have the following elements[2]

1. Areas with fast and slow velocities of conduction

2. Different refractory periods

3. A functional core where the circuit exists

These elements are present in a typical atrial flutter in the CTI. The initiation of atrial flutter is due to an ectopic beat that depolarizes one segment of the pathway of the circuits that become refractory and starts the tachycardia from a no-refractory segment.[3]

Epidemiology

Atrial flutter is the second most common cardiac arrhythmia after atrial fibrillation.[4]

It is commonly associated with atrial fibrillation, but the incidence and the prevalence of the atrial flutter are less known when compared with atrial fibrillation.[4]

Atrial flutter in common in patients with underlying diseases such as chronic obstructive pulmonary disease, pulmonary hypertension, and heart failure.

Isolated atrial flutter in the absence of abnormal heart anatomy is rare and usually is present when atrial size abnormalities have developed.[5]

Atrial flutter is more frequent in males than in females. Aging is a significant risk factor as other associated disorders in patients with atrial fibrillation include systemic hypertension, diabetes mellitus, and history of alcohol abuse.

Older age is associated with an increased risk of atrial fibrillation and atrial flutter.

Pathophysiology

Typical Atrial Flutter

Typical atrial flutter is the most common type of atrial flutter and is a macroreentrant atrial tachycardia that uses the CTI as an essential part of the circuit. The Todaro tendon, crista terminalis, the inferior vena cava, the tricuspid valve annulus, and the coronary sinus os delineate the circuit. These structures are essential to provide the pathway length for the flutter system.

The CTI provides the slow conduction pathway, and it presents in the lateral aspect of the younger patient and the medial aspect in the older patients.  The mechanism of slow conduction is not well understood but might be related to anisotropic fiber orientation. With aging and atrial dilation, occurs fibrosis of the atrial tissue and produce non-uniform anisotropic conduction through the CTI. 

The crista terminalis is a functional barrier that induces a transverse conduction block, steep slope, and arborization that allows the circuit to exist.

The mechanism of arrhythmia is a macro-reentry activation of the right atrium from the interatrial septum and along the crista terminalis with passive activation of the left atrium via the coronary sinus muscular connection.[6][7]

As this cycle occurs in the atrium, conduction is determined by the atrioventricular node mechanism to conduct the atrial impulse.  Commonly the atrioventricular conduction will be 2 to 1 with an atrial rate of 300 beats per minute with a ventricular rate of 150 beats per minute, but this can be variable depending on the underlying parasympathetic stimulus or refractoriness of the atrioventricular node. 

The absence of an isoelectric line between P waves or QRS complexes is due to the constant cycling of the circuit or atrial activation.

The reason behind the existence of the circuit might relate to the nature of the anatomical structures that are circumscribing the circuit. The crista terminalis thickness might have the capacity to block conduction, as well as the low voltage of the CTI, can be signs of arrhythmogenesis and poor conduction in the right atrium.

 Atypical Atrial Flutter

Atypical atrial flutter or other macroreentrant atrial tachycardia has a circuit configuration different from the typical right atrial flutter circuit. Electrophysiologic studies and intracardiac mapping are the only means to determine the exact mechanism or area generating the atrial flutter. Different from typical atrial flutter, the presence of atypical atrial flutter is related to structural heart diseases as prior cardiac surgery or ablation procedures.[8]

When the atrial flutter is determined to come from the right atrium but not associated with the CTI system, the circuit can be in the superior vena cava and part of the terminal crest. When prior surgery or intervention occurred, the presence of scar can often become arrhythmogenic, and the center of the circuit and the onset of the arrhythmia mostly occur after several years of the procedure, likely secondary to remodeling.[9]

In patients without prior cardiac intervention, the atrial flutter circuit can be low voltage areas like the lateral right atrium,[10] this might be secondary to fibrosis due to chronic atrial high pressures, or cardiomyopathy that can produce fibrosis of the myocardium and creating low voltage areas that allow atrial flutter to occur.[10]

Left atrial flutter can be associated with surgical atriotomy scars or areas of prior ablations, combined with areas of low voltage.[11]

Electrophysiologic studies and mapping of the right and left atrium are necessary to determine the specific location and mechanism of the arrhythmia to guide the ablation. In the presence of an intra-atrial septal macro-reentrant system, the success rate is low when compared with the free wall atrial tachycardias.[12]

History and Physical

Patients with atrial flutter can be asymptomatic or present with symptoms as palpitations, lightheadedness, fatigue, and shortness of breath especially in the presence of rapid ventricular conduction.

Decreased exercise tolerance is another symptom that can be present during patient evaluation.

During the rapid ventricular rate, hypotension, syncope and near syncope can occur in susceptible patients with high ventricular rates.

Some patients remain asymptomatic until they develop acutely decompensated heart failure, tachycardia-induced cardiomyopathy, and embolic stroke.

The physical exam in patients with atrial flutter will show regular or irregularly regular peripheral pulse (due to variable conduction from the atrioventricular node), jugular venous distension, respiratory sounds with crackles in lung fields, tachycardia, abdominal distention, and lower extremities edema when congestion occurs. 

Evaluation

Initial evaluation of the underlying rhythm is necessary, and determination of possible etiology or trigger is crucial.

Electrocardiogram:

Electrocardiogram generally shows flutter waves with the absence of an isoelectric line between QRS complexes, with an atrial wave around 300 beats per minute with ventricular conduction that can be 2 to 1, 3 to 1 or 4 to 1 or with variable conduction due to Wenckebach phenomenon.

In inferior leads, typical flutter waves resemble a picket fence or sawtooth because the P waves are negative due to the direction of the vector.

Typical atrial flutter with counterclockwise activation will show inferior leads with negative flutter waves with low amplitude in lead I and upright flutter wave in aVL.[9]

Echocardiogram

Echocardiography for the evaluation of atrial flutter bases its value on the determination of underlying structural heart disease. Presence of dilated atrial chambers is a sign of chronicity and also fibrosis of the atrium that could make the circuit persist and more challenging to control.[13]

Assessment of left ventricular ejection fraction can be the cause or consequence of underlying atrial flutter because the persistence of tachycardia can generate tachycardia induced-cardiomyopathy or the cardiomyopathy and volume status can trigger the atrial flutter. 

Evaluation for atrial or ventricular thrombus is also important, especially when desiring cardioversion to sinus rhythm. A transesophageal echocardiogram is the modality of choice because it can visualize the atrial appendage where atrial thrombus is more frequently present.[14]

Laboratory evaluation

An initial determination of atrial flutter triggers is necessary. Laboratory evaluation of electrolytes disturbance, abnormal thyroid function, infection, anemia, hypoxia. Correction of these abnormalities can improve symptoms and decrease the threshold of development of atrial flutter and rapid ventricular response.

Pulmonary function test might be necessary for this set of patients; there is a correlation between lung disease and presence the atrial arrhythmias including atrial flutter. Management of the underlying lung condition can improve the control of the atrial flutter.

Treatment / Management

Treatment management should focus on the following aspects:

  1. Rhythm control
  2. Rate control
  3. Anticoagulation due to embolization risk

1Rhythm control

Maintenance of the sinus rhythm or conversion of the sinus rhythm is essential. 

Persistence of atrial flutter, can cause chronic remodeling of the atrium and make it more difficult to manage the rate and the conversion or maintenance of sinus rhythm.

There are different ways to achieve sinus rhythm: with electrical cardioversion, pharmacological cardioversion and ultimately with catheter ablation.

The rhythm strategy divides into acute and long term management.

In the acute setting, in patients with atrial flutter who are hemodynamically unstable, synchronized cardioversion is indicated for the conversion of sinus rhythm to stabilize the patient.[15]

In stable patients, pharmacological cardioversion is achievable with different antiarrhythmics.  Antiarrhythmic drugs like amiodarone, class IA (procainamide, quinidine, and disopyramide) and IC drugs (flecainide and propafenone), calcium channel blockers (verapamil, diltiazem), and beta-blockers (metoprolol, carvedilol, esmolol) are some of the choices for pharmacological cardioversion.[16]

Despite the multiple pharmacological options the control and conversion of atrial flutter to sinus rhythm is difficult. The mechanisms by which antiarrhythmic drugs maintain sinus rhythm is by prevention of premature beats that usually start the activation of the tachycardia circuit by a reentrant or an ectopic beat. 

In the presence of a new diagnosis of atrial flutter, one should start the patient on anticoagulation. In the absence of intracardiac thrombus, electrical cardioversion in stable patients can be considered, especially to prevent persistence of the arrhythmia and further fibrosis that will perpetuate the presence of atrial flutter and more difficult to control or to convert to sinus rhythm.[17]

In patients who have a contraindication to these drugs or do not tolerate them may consider catheter ablation of the atrial flutter circuit.[18]

Radiofrequency catheter ablation of the CTI is the standard treatment for typical atrial flutter with a success rate of 95% with few complications post-procedure.[19] The procedure consists placement of intracardiac catheters into the coronary sinus, the atrium, and an ablation catheter. The anatomical target for the CTI is found through a mapping and entrapment technique. After this, the linear lesion is made by the ablation catheter with the use of radiofrequency energy. At the end of the ablation when the line is complete, verification bidirectional conduction block and absence of atrial flutter is done to confirm ablation is complete.  In the rare cases of medication and ablation failure, atrioventricular nodal ablation with the placement of a pacemaker might be indicated to prevent atrial to ventricular conduction of rapid atrial flutter.

2Rate control

Rate control is achievable with the use of atrioventricular nodal agents as calcium channel blockers (first line) or beta blockers.[20] Digoxin is another option for rate control but needs to be used carefully due to its side effects and toxicity.

Combination of these agents is an option.

Adequate control of the atrial flutter through AV nodal agents is difficult because atrial flutter continuously fires at the same rate to the AV node. 

The heart rate goal should be below 110 beats per minute.[21] This was determined after the RACE II trial (Rate Control Efficacy in Permanent Atrial Fibrillation: a Comparison between Lenient versus Strict Rate Control II). This study compared strict heart rate control of <80 bpm versus <110bpm, this study showed that very stringed heart rate control is not necessary and more lenient control reduces polypharmacy and fewer side effects and less outpatient visits. This study was in patients with atrial flutter but can extrapolate to the rate control of atrial flutter.

In patients who are intolerant of medications or have significant bradycardia due to rate control measures, a catheter ablation is an option.

3Anticoagulation due to the risk of embolic events:

Patients with atrial flutter have a similar risk of strokes as those with atrial fibrillation.[22]

Use of a scoring system to determine the annual risk of stroke must be used such as the CHADS2-Vasc.[23] This scoring system helps to risk stratify the patient according to their risk of developing embolic strokes due to atrial flutter or atrial fibrillation. The presence of congestive heart failure, systemic hypertension, diabetes, female sex, age between 65 to 74 years and a history of the peripheral vascular disease score as one point for each comorbidity that is present. 

Age more than 75 years old and a history of stroke are two additional points each.

The presence of one point can give the patient an annual risk of 1.3% of embolic stroke per year when two points the risk is 2.2%. In patients with two or more points, the use of anticoagulation is a strong recommendation. In patients with one point, one may use either aspirin or full anticoagulation.

Differential Diagnosis

  • Atrial fibrillation: mostly irregular, no evidence of organized atrial activity in the electrocardiogram, absence of P waves
  • Multifocal atrial tachycardia: multiple P waves morphology due to the presence of several atrial pacers
  • Atrial tachycardia with variable conduction: the isoelectric line between QRS complexes

Prognosis

Prognosis of patients with typical atrial flutter undergoing catheter ablation is good with a recurrence rate of less than 5%.

Persistence of atrial flutter can generate tachycardia induce cardiomyopathy that is hard to control causing multiple hospitalizations due to decompensation.

Complications

The most common complication of atrial flutter is the increased risk of embolic stroke and disability related to this event.

Hemodynamically instability is also possible especially in patients with a rapid ventricular response.

Chronicity and poor control of atrial flutter can generate tachycardia induce cardiomyopathy and also can produce hard to control heart failure.

The complications secondary to the use of antiarrhythmic drugs are related to the type of drug and underlying mechanism of the drug. 

Atrial flutter ablation complications also depend on the side of the origin of the atrial flutter. Right-sided atrial flutter is related to fewer complication rates than left-sided atrial flutter ablation, and this is due to the need for creating a transeptal communication during the procedure to reach the left atrium foci of arrhythmia and perform the ablation. The transseptal puncture produces transient communication between the left and right chambers of the heart. There is also increasing the risk of embolic strokes with left-sided atrial flutter ablation when compared with right side procedures. 

Enhancing Healthcare Team Outcomes

The management of atrial flutter by a multidisciplinary team including physicians, specialists, and a cardiac specialty nurse is recommended. While the cardiologist may initiate the initial treatment, the majority of patients are followed by the primary provider or nurse practitioner. These patients need life-long follow up because there is a risk of an embolic stroke. If the disorder receives inadequate therapy, it leads to poor quality of life. Despite advances in treatment, recurrence and multiple admission to the hospital are very common.


  • Image 6481 Not availableImage 6481 Not available
    Contributed by Steve Bhmji, MS, MD, PhD
Attributed To: Contributed by Steve Bhmji, MS, MD, PhD

Interested in Participating?

We are looking for contributors to author, edit, and peer review our vast library of review articles and multiple choice questions. In as little as 2-3 hours you can make a significant contribution to your specialty. In return for a small amount of your time, you will receive free access to all content and you will be published as an author or editor in eBooks, apps, online CME/CE activities, and an online Learning Management System for students, teachers, and program directors that allows access to review materials in over 500 specialties.

Improve Content - Become an Author or Editor

This is an academic project designed to provide inexpensive peer-reviewed Apps, eBooks, and very soon an online CME/CE system to help students identify weaknesses and improve knowledge. We would like you to consider being an author or editor. Please click here to learn more. Thank you for you for your interest, the StatPearls Publishing Editorial Team.

Atrial Flutter - Questions

Take a quiz of the questions on this article.

Take Quiz
A 72-year-old man with a history of chronic obstructive pulmonary disease (COPD) and hypertension presents with palpitations and shortness of breath ongoing for three days. The patient was in his normal state of health before this time. Physical exam reveals a tachycardic, but regular heart rhythm, no murmurs, rubs or gallops; lungs demonstrate trace rales bilaterally. Labs demonstrate potassium of 3.8 mEq/dL, BUN of 18 mg/dL, and creatinine of 1.0 mg/dL. An EKG is performed which demonstrates a narrow complex, regular rhythm with sawtooth appearing atrial activity. The ventricular rate on the EKG is 150 beats per minute. Without further workup, which of the management options below is contraindicated?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
In a patient who has had atrial flutter for 1 month, what important study is required?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
In a patient with atrial flutter, what is the most important aspect of therapy?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
Which class of drugs can be used to control ventricular rate in an atrial flutter?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
What is the best treatment for a 70-year-old female with history of hypertension presenting with palpitations after the onset of an upper respiratory infection? She is tachycardic, has a BP of 115/72, and has atrial flutter with a 2:1 AV block.



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A 70-year-old female with chronic stable angina and hypertension is brought to the emergency department with two hours of chest discomfort, palpitations, lightheadedness, and shortness of breath. Blood pressure is 85/60 mmHg, heart rate is 150 bpm, respirations 28, and oxygen saturation on room air is 90 percent. The cardiac exam show tachycardia without extra heart sounds, there is jugular venous distention with flutter waves, and there are pulmonary rales. An ECG shows atrial flutter with 2 to 1 AV conduction. No ischemic changes are noted. Select the appropriate management.



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
An ECG reveals a regular, narrow complex tachycardia with atrial activity in a "saw tooth" pattern. The atrial rate appears to be around 300 bpm. Ventricular activity is at 150 BPM. What is the likely diagnosis?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
Which of the following should be done in the management of a patient with symptomatic recurrent atrial flutter?



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up
A patient has been admitted to the cardiology floor. After hooking him up the cardiac monitor, you note the rhythm in the image below. What is true about this condition? Select all that apply.

(Move Mouse on Image to Enlarge)
  • Image 6481 Not availableImage 6481 Not available
    Contributed by Steve Bhmji, MS, MD, PhD
Attributed To: Contributed by Steve Bhmji, MS, MD, PhD



Click Your Answer Below


Would you like to access teaching points and more information on this topic?

Improve Content - Become an Author or Editor and get free access to the entire database, free eBooks, as well as free CME/CE as it becomes available. If interested, please click on "Sign Up" to register.

Purchase- Want immediate access to questions, answers, and teaching points? They can be purchased above at Apps and eBooks.


Sign Up

Atrial Flutter - References

References

Bun SS,Latcu DG,Marchlinski F,Saoudi N, Atrial flutter: more than just one of a kind. European heart journal. 2015 Sep 14     [PubMed]
Pytkowski M,Jankowska A,Kraska A,Sterliński M,Kowalik I,Krzyzanowski W,Szwed H, [Pharmacological versus invasive treatment in patients with atrial fibrillation]. Polskie Archiwum Medycyny Wewnetrznej. 2004 Jun     [PubMed]
Cosío FG, Atrial Flutter, Typical and Atypical: A Review. Arrhythmia     [PubMed]
Matsuo K,Uno K,Khrestian CM,Waldo AL, Conduction left-to-right and right-to-left across the crista terminalis. American journal of physiology. Heart and circulatory physiology. 2001 Apr     [PubMed]
Watson RM,Josephson ME, Atrial flutter. I. Electrophysiologic substrates and modes of initiation and termination. The American journal of cardiology. 1980 Apr     [PubMed]
Granada J,Uribe W,Chyou PH,Maassen K,Vierkant R,Smith PN,Hayes J,Eaker E,Vidaillet H, Incidence and predictors of atrial flutter in the general population. Journal of the American College of Cardiology. 2000 Dec     [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]
    [PubMed]

Disclaimer

The intent of StatPearls is to provide practice questions and explanations to assist you in identifying and resolving knowledge deficits. These questions and explanations are not intended to be a source of the knowledge base of all of medicine, nor is it intended to be a board or certification review of EMS-Paramedic. The authors or editors do not warrant the information is complete or accurate. The reader is encouraged to verify each answer and explanation in several references. All drug indications and dosages should be verified before administration.

StatPearls offers the most comprehensive database of free multiple-choice questions with explanations and short review chapters ever developed. This system helps physicians, medical students, dentists, nurses, pharmacists, and allied health professionals identify education deficits and learn new concepts. StatPearls is not a board or certification review system for EMS-Paramedic, it is a learning system that you can use to help improve your knowledge base of medicine for life-long learning. StatPearls will help you identify your weaknesses so that when you are ready to study for a board or certification exam in EMS-Paramedic, you will already be prepared.

Our content is updated continuously through a multi-step peer review process that will help you be prepared and review for a thorough knowledge of EMS-Paramedic. When it is time for the EMS-Paramedic board and certification exam, you will already be ready. Besides online study quizzes, we also publish our peer-reviewed content in eBooks and mobile Apps. We also offer inexpensive CME/CE, so our content can be used to attain education credits while you study EMS-Paramedic.