Atrial Flutter

Overview

Atrial flutter is a heart rhythm disorder in which the upper chambers of the heart (atria) beat very rapidly and regularly. Normally, the atria contract regularly 60-100 times per minute. In atrial flutter, however, the atria beat 250-350 times per minute, sometimes even accelerating to 400.

In atrial flutter, electrical signals in the upper chambers of the heart continuously circulate in a loop. This loop usually occurs in the right atrium, in the area between the superior and inferior vena cava. The electrical signal continues to rotate very rapidly in this loop and forces the atria to contract excessively fast.

When the atria beat this rapidly, they cannot pump blood effectively. Fortunately, the heart's natural protective mechanism kicks in. The AV node (the gateway between the atria and ventricles) does not let every electrical signal through. It usually lets through one out of every two or four beats. This allows the lower chambers to beat at a manageable rate (usually 75 to 150 times per minute), which helps maintain stable circulation and prevents the heart from reaching dangerously high rates. This situation, however, still makes it difficult to pump enough blood to the body.

Atrial flutter is closely related to atrial fibrillation. The two are often seen together and transitions from one to the other can occur. Atrial flutter has a regular rhythm, while atrial fibrillation has an irregular rhythm. You can distinguish the irregularity by checking your pulse.

Atrial flutter is a treatable condition. Medication, electrical cardioversion, and especially catheter ablation are effective treatment options.

Symptoms

The symptoms of atrial flutter vary from person to person. In some people there are no symptoms and the condition is discovered by chance. In others, the symptoms are noticeable and bothersome.

The most common symptoms are:

• Heart palpitations. Feeling the heart beating rapidly and regularly in the chest is the most common symptom. Palpitations are usually continuous and can last for hours or days.
• Dizziness and lightheadedness. When the heart does not pump effectively, the brain may not receive enough blood. This creates dizziness.
• Shortness of breath. Breathing can become difficult, especially during exercise or when lying down.
• Chest discomfort. A feeling of discomfort, pressure, or tightness in the chest may be felt.
• Fatigue and weakness. When the body does not receive enough blood, a constant feeling of tiredness develops.
• Reduced exercise capacity. Activities that were previously done easily become difficult.
• Fainting. Rarely seen but fainting can occur when blood flow to the brain is severely reduced.
• Anxiety. Rapid heartbeat can create feelings of worry and concern.

Symptoms may be continuous or intermittent. In some people, atrial flutter comes and goes in episodes (paroxysmal atrial flutter). In others it continues constantly (persistent atrial flutter).

When to See a Doctor

See a doctor in the following situations:

• If you regularly experience heart palpitations, see a cardiologist.
• If chest pain, severe shortness of breath, or fainting develops together with palpitations, call emergency services immediately.
• If fatigue and shortness of breath are gradually increasing, evaluation is important.
• If you have been previously diagnosed with atrial flutter and symptoms are worsening, notify your doctor.

Causes and Risk Factors

Atrial flutter is usually associated with heart disease or conditions that cause stress on the heart. Sometimes, however, it can also develop in a healthy heart.

The most important causes and risk factors are:

• Age. Risk increases with age. It is more common over the age of 60.
• Heart valve disease. Mitral valve diseases in particular increase the risk of atrial flutter. Those who have undergone valve surgery are also at risk.
• High blood pressure. Uncontrolled high blood pressure thickens the heart muscle and increases the risk of atrial flutter.
• Heart failure. When the heart pumps weakly, the atria stretch and the risk of flutter developing increases.
• Coronary artery disease. Narrowing or blockage in the heart vessels increases the risk of atrial flutter.
• Heart surgery. Atrial flutter is common especially in the first weeks and months after open heart surgery.
• Lung diseases. Chronic obstructive pulmonary disease (COPD), pulmonary embolism, and other lung problems create stress on the heart and increase the risk of flutter.
• Thyroid diseases. Overactive thyroid (hyperthyroidism) increases heart rate and sets the stage for rhythm disorders.
• Diabetes. Diabetes can lead to heart damage and rhythm disorders in the long term.
• Obesity. Excess weight puts extra load on the heart and increases the risk of atrial flutter.
• Sleep apnea. Breathing pauses during sleep create stress on the heart and increase the risk of rhythm disorders.
• Excessive alcohol use. Chronic alcohol consumption or binge drinking episodes can trigger atrial flutter.
• History of atrial fibrillation. People with atrial fibrillation have a high risk of developing atrial flutter. The two conditions are often seen together.

Complications

If left untreated, atrial flutter can lead to serious complications.

• Stroke. This is the most serious complication. When the atria do not pump effectively, blood stagnates and clots can form. A clot can break loose and block blood vessels in the brain. The risk of stroke in atrial flutter is slightly lower than in atrial fibrillation but is still significant.
• Heart failure. Long-lasting rapid heartbeat can weaken the heart muscle. If heart failure already exists, flutter can worsen the condition further.
• Cardiomyopathy. If continuous rapid heartbeat continues for years, the heart muscle can enlarge and weaken. This is called tachycardia-induced cardiomyopathy.
• Transition to atrial fibrillation. Atrial flutter often converts to atrial fibrillation or the two are seen together.
• Decline in quality of life. Constant fatigue, shortness of breath, and palpitations negatively affect daily life, work performance, and social activities.

Diagnosis

Atrial flutter is diagnosed with an electrocardiogram (ECG).

The diagnostic process typically includes:

• Electrocardiogram (ECG). This is the most important diagnostic tool. In atrial flutter, typical sawtooth waves are seen on the ECG. These are called flutter waves. Heart rate is usually rapid, either regularly or irregularly. The ECG helps distinguish atrial flutter from atrial fibrillation.
• Holter monitor. This is a portable ECG device worn for twenty-four hours or longer. It is used to capture intermittent flutter episodes.
• Event recorder. This is a small device worn for weeks or months. You activate it when you feel palpitations and the rhythm at that moment is recorded.
• Echocardiography. This assesses the structure of the heart and its pumping strength. Valve diseases, atrial enlargement, and heart failure are detected. It also investigates whether atrial clots are present.
• Transesophageal echocardiography (TEE). An ultrasound probe is placed into the heart through the esophagus. It images the left atrium and its appendage in great detail. It is used to look for clots before cardioversion.
• Blood tests. Thyroid function, electrolyte levels, and kidney function are checked.
• Electrophysiology study. In rare cases, the exact location of the flutter circuit is mapped via cardiac catheterization. This is usually done during catheter ablation for treatment purposes.

Treatment

Atrial flutter treatment has two main goals: controlling heart rate and restoring normal rhythm. Blood thinner treatment is also needed to reduce stroke risk.

Treatment options include:

• Rate control medications. These slow rapid heartbeats but do not convert flutter to normal rhythm. Beta blockers (metoprolol, atenolol), calcium channel blockers (diltiazem, verapamil), or digoxin may be used. These medications reduce symptoms and protect the heart.
• Rhythm control medications. These aim to convert atrial flutter to normal rhythm. Antiarrhythmic medications (dofetilide, ibutilide, flecainide, propafenone, amiodarone, sotalol) may be used. These medications have side effects, however, and must be carefully monitored.
• Blood thinner treatment (anticoagulation). Blood thinners are used to reduce stroke risk. Warfarin or newer blood thinners (apixaban, rivaroxaban, edoxaban, dabigatran) may be used. The decision about blood thinners is made based on a risk assessment called the CHA2DS2-VASc score. Factors such as age, heart failure, high blood pressure, diabetes, and previous stroke increase risk. In high-risk patients, blood thinners are used lifelong.
• Electrical cardioversion. A controlled electrical shock is applied through the chest wall. This shock restores the heart to normal. The procedure is performed under brief anesthesia and is very effective. Atrial flutter usually returns to normal with a low-energy shock. It is preferred in emergency situations or when medication does not work.
• Catheter ablation. This is the most effective method for permanently treating atrial flutter. A thin catheter is advanced to the heart through a vessel in the groin. A small lesion is created with radiofrequency energy in the critical area where the flutter circuit passes (usually between the tricuspid valve and the inferior vena cava). This lesion breaks the circuit and stops the flutter. The procedure takes one to two hours and has a success rate of 90-95 percent. Most people recover completely after the procedure. An overnight stay in the hospital may be required or discharge can happen the same day. Catheter ablation is the first-choice treatment especially for recurrent flutter.
• Treatment of underlying causes. High blood pressure is brought under control. Thyroid disease is treated. Heart failure treatment is optimized. If sleep apnea is present, a CPAP device is used.

Living with Atrial Flutter

After catheter ablation, most people recover completely and flutter does not recur. If ablation has not been performed or if medication is being taken, certain points should be kept in mind.

If you have atrial flutter, pay attention to the following:

• Use your medications regularly. Use blood thinners, rate control, or rhythm control medications regularly as your doctor recommends. Medication interruption can lead to serious complications.
• Have regular follow-up. Do not miss your cardiology appointments. If you are using warfarin as a blood thinner, regular INR testing is needed.
• Watch for signs of bleeding. While using blood thinners, notify your doctor if gum bleeding, nosebleeds, blood in urine or stool, or unusual bruising develops.
• Adopt a healthy lifestyle. Lose weight, exercise regularly, reduce salt intake, limit or completely stop alcohol consumption.
• Control your high blood pressure. Use your blood pressure medications regularly and measure your blood pressure at home.
• Treat your sleep apnea. Do not skip using your CPAP device.
• Avoid triggers. Excessive caffeine, alcohol, and stress can trigger flutter.
• Inform before new medication or procedures. Before any medical procedure, dental treatment, or starting a new medication, be sure to mention that you are using blood thinners.
• Recognize signs of atrial fibrillation. Flutter can convert to atrial fibrillation. If you notice a rhythm change, notify your doctor.

Preparing for Your Appointment

What you can do:

• When did heart palpitations start and how often do they occur?
• Are palpitations continuous or intermittent?
• What symptoms are you experiencing?
• Did you notice any triggering factors?
• List all medications and supplements you are taking.
• Mention if there is a family history of heart disease or stroke.
• Write your questions down in advance.

Questions you can ask your doctor:

• Is the diagnosis of atrial flutter certain?
• What is the most appropriate treatment for me?
• How successful and risky is catheter ablation?
• Do I need to use blood thinners? For how long?
• What is my stroke risk?
• Can I exercise?
• What is my risk of converting to atrial fibrillation?

Your doctor may ask you:

• When did heart palpitations start?
• Are palpitations continuous or intermittent?
• What symptoms are you experiencing?
• Have you fainted?
• Have you had heart disease before?
• Do you have high blood pressure?
• Do you have sleep apnea?
• What medications are you taking?