Atrial Flutter
What Is Atrial Flutter?
Atrial flutter is a heart rhythm disorder originating in the upper chambers of the heart, called the atria. It typically causes a rapid and often regular heartbeat.
Unlike atrial fibrillation, atrial flutter usually involves a more organized electrical circuit within the atria.
The atria may contract at rates of approximately 250–350 beats per minute, while the ventricular rate is generally lower. With 2:1 atrioventricular conduction, the heart rate is often approximately 150 beats per minute.
Atrial flutter may occur independently or coexist with atrial fibrillation.
One of its most important complications is ischemic stroke, which may result from blood clot formation inside the heart.
What Are the Symptoms of Atrial Flutter?
Symptoms vary between patients. Common symptoms include:
- Rapid, often regular palpitations
- Sudden episodes of increased heart rate
- Shortness of breath
- Fatigue and weakness
- Dizziness or lightheadedness
- Chest discomfort or pressure
- Reduced exercise tolerance
- Occasionally, fainting
Some patients may have no noticeable symptoms.
A persistently elevated heart rate may eventually impair the pumping function of the heart.
What Causes Atrial Flutter?
Atrial flutter occurs when electrical impulses circulate continuously through a specific pathway within the atria.
Common associated conditions include:
- Hypertension
- Advanced age
- Coronary artery disease
- Heart failure
- Heart valve disease
- Previous cardiac surgery or cardiac interventions
- Congenital heart disease
- Chronic lung disease
- Obesity and sleep apnea
- Hyperthyroidism
- Excessive alcohol consumption
Atrial flutter may also occur in patients without known structural heart disease.
How Is Atrial Flutter Diagnosed?
1. Electrocardiogram (ECG)
An ECG is the primary diagnostic test.
Typical atrial flutter often produces characteristic sawtooth-shaped flutter waves on the ECG.
2. Holter Monitoring
Continuous ECG monitoring for 24–48 hours or longer may be necessary when episodes occur intermittently.
3. Echocardiography
Echocardiography evaluates cardiac function, atrial size, heart valves, and possible underlying structural abnormalities.
4. Blood Tests
Thyroid function, electrolyte levels, kidney function, and other relevant laboratory parameters may be assessed.
5. Electrophysiological Study (EPS)
In selected patients, an electrophysiological study may be performed to identify the mechanism of the arrhythmia and guide catheter ablation.
How Is Atrial Flutter Treated?
Treatment aims to restore normal sinus rhythm, control the heart rate, prevent recurrence, and reduce the risk of stroke.
1. Heart Rate Control Medications
Beta blockers or certain calcium channel blockers may be used to control a rapid ventricular rate in appropriate patients.
However, controlling heart rate with medication can sometimes be challenging in atrial flutter.
2. Anticoagulant Therapy
Atrial flutter is associated with an increased risk of thromboembolism and stroke.
The need for anticoagulation is generally assessed using the same stroke risk principles applied to atrial fibrillation.
Restoration of normal sinus rhythm does not automatically eliminate the need for anticoagulant treatment.
3. Electrical Cardioversion
Electrical cardioversion is performed under short-term anesthesia or sedation.
A controlled electrical shock is delivered to restore normal sinus rhythm.
Atrial flutter generally responds well to electrical cardioversion.
The duration of the arrhythmia, anticoagulation status, and thromboembolic risk must be evaluated before the procedure.
4. Antiarrhythmic Medications
Antiarrhythmic medications may be used in selected patients to restore sinus rhythm or reduce recurrent episodes.
However, catheter ablation is often an effective alternative to long-term antiarrhythmic drug therapy, particularly in recurrent typical atrial flutter.
5. Catheter Ablation
Catheter ablation is a highly effective treatment for typical atrial flutter, with high procedural success rates.
The procedure is usually performed through catheters introduced into veins in the groin.
In typical atrial flutter, the target is the cavotricuspid isthmus (CTI), a critical part of the electrical circuit responsible for the arrhythmia.
Radiofrequency energy is applied to interrupt this circuit and prevent recurrence.
In experienced centers, the acute procedural success rate of typical atrial flutter ablation generally exceeds 90–95%.
The risk of recurrent typical flutter after successful ablation is relatively low. However, atrial fibrillation may develop later in some patients.
Atypical atrial flutter, particularly after previous cardiac surgery or catheter ablation, may require more advanced electrical mapping and individualized ablation strategies.
What Is the Difference Between Atrial Flutter and Atrial Fibrillation?
Both conditions originate in the atria, but their electrical mechanisms differ.
Atrial fibrillation involves disorganized atrial electrical activity and usually causes an irregular heartbeat.
Atrial flutter involves a more organized electrical circuit and often produces a rapid, regular heartbeat. However, the ventricular rhythm may become irregular when atrioventricular conduction varies.
Catheter ablation for typical atrial flutter generally has a higher procedural success rate than ablation for atrial fibrillation.
Is Atrial Flutter Dangerous?
Potential complications include:
- Ischemic stroke and systemic embolism
- Impaired cardiac function due to prolonged rapid heart rates
- Heart failure
- Reduced exercise tolerance
- Recurrent arrhythmia episodes
Appropriate treatment and regular follow-up can reduce these risks.
Can Atrial Flutter Be Cured?
In patients with typical atrial flutter, catheter ablation can permanently eliminate the flutter circuit in most cases.
However, successful ablation does not prevent the possible development of atrial fibrillation later in life.
Therefore, continued rhythm monitoring and individualized stroke risk assessment remain important after treatment.
When Should You Consult a Cardiologist?
Patients with recurrent rapid palpitations, unexplained fatigue, shortness of breath, dizziness, or reduced exercise tolerance should seek a cardiology evaluation.
Severe chest pain, fainting, significant breathing difficulty, or symptoms suggesting stroke require immediate emergency medical attention.
Assoc. Prof. Sezen Bağlan Uzunget, MD
Cardiologist
This content is provided for general educational purposes. Diagnosis and treatment should be individualized according to the patient's clinical condition.
Türkçe: Atriyal Flutter