Atrial flutter is a heart disorder in which the heart beats very much faster than normal.
The condition is same as that to atrial fibrillation — which is the most common type of arrhythmia (abnormal heartbeat) — and it can cause similar symptoms and complications.
Atrial flutter is very less common than atrial fibrillation, and people with atrial flutter can also have episodes of atrial fibrillation.
Causes of Atrial Flutter
Generally, your heartbeat begins with an electrical signal that is given out by the sinus node, a cluster of cells located in the upper right heart chamber (right atrium).
This signal goes from the right atrium to the left atrium and tells both of these chambers to pump blood into the lower heart chambers (right and left ventricles).
The signal then goes to the atrioventricular node, near the center of the heart, where it is slowed down briefly to allow the ventricles to fill with blood.
The signal then passes through the ventricles, causing those chambers to pump blood to the rest of the body.
A normal resting heart rate is about 60 to 100 beats per minute.
In people suffering with atrial flutter, the heart's electrical signal gets stuck repeating in the right atrium, causing the atria to contract rapidly (about 300 times per minute).
The atrioventricular node can't conduct impulses this quickly, but about half of the signals from the atria still make it to the ventricles, causing the lower heart chambers to pump at about 150 beats per minute.
Atrial flutter causes the heart to beat in a fast but regular pattern unlike atrial fibrillation, which causes a fast and irregular pattern.
Atrial flutter makes a distinctive "sawtooth" pattern on an electrocardiogram (EKG or ECG), a test that is used to monitor the heart and diagnose heart rhythm disorders.
Like atrial fibrillation, atrial flutter develops from health conditions that affect the heart's internal electrical system.
Symptoms & Complications of Atrial Flutter
Aside from a rapid heart rate, symptoms of atrial flutter include:
- Palpitations (racing, pounding, or fluttering of the heart)
- Chest pain or tightness
- Shortness of breath
- Lightheadedness, dizziness, or fainting
- Low blood pressure
Some people don't experience any symptoms from atrial flutter.
Blood regulates more slowly through the heart and can stagnate, allowing small blood clots to form. These clots can move to the brain and block an artery, causing a stroke or a cold arm or leg, for example, the clots travel to a major artery in your limbs.
Also, in people suffering with atrial flutter, the ventricles do not completely fill with blood and may not pump enough blood to meet the body's needs, resulting in heart failure.
Diagnosis & Treatment of Atrial Flutter
Atrial flutter is diagnosed depending on your medical and family history, a physical exam, and an EKG.
If an EKG shows that you are having atrial flutter, your doctor can also conduct an ultrasound of your heart (echocardiogram) to evaluate your heart and spot any blood clots.
Many classes of medication can help in slowing your heart rate, including beta blockers, calcium channel blockers, and digoxin. Blood thinners (anticoagulants) or aspirin can help reduce your risk of blood clots.
A procedure known as electrical cardioversion — in which you're given a brief, low-power electrical shock through your chest— is often used to restore a normal sinus heart rhythm.
However, this treatment is effective people often experience a return of arrhythmia at some point in the future.
Anti-arrhythmic medication, such as sodium-channel or potassium-channel blockers, can help in restoring a normal rhythm or maintain normal rhythm after electrical cardioversion.
Else, your doctor can advise radio frequency ablation to convert an atrial flutter to normal sinus rhythm.
In this procedure, a surgeon will thread a catheter to your heart and will use radio wave energy to create scar tissue that blocks the abnormal electrical pathways involved in atrial flutter.