Atrial flutter

Atrial flutter explained

Your heartbeat is controlled by an electrical system. It makes the upper chambers (atria) and lower chambers (ventricles) of your heart work together to pump blood around the body.

If you have atrial flutter this electrical pathway is interrupted and a new, smaller faulty pathway forms in the atria instead.

Because the new pathway is so small, the impulses travel very quickly around your atria. This causes your atria to beat much faster than it should (around 300 beats per minute instead of the usual 60-100). This causes an abnormal heart rhythm (arrhythmia).

Your ventricles cannot pump as fast as the atria. This means your atria and your ventricles beat at different speeds, putting your heart under strain.

Symptoms of atrial flutter

Although people with atrial flutter often have no symptoms, symptoms can include:

• palpitations
• shortness of breath
• feeling very tired (fatigue)
• feeling light-headed
• fainting
• tightness in your chest.

If you're experiencing any of these symptoms, especially if you already have a heart condition, speak to your GP.

Causes of atrial flutter

People with atrial flutter often have an underlying cause, such as:

• previous cardiac surgery
• coronary heart disease
• heart valve disease
• congenital heart disease
• high blood pressure.

More rarely, atrial flutter can be caused by:

• cardiomyopathy
• inflammation of the heart (such as myocarditis)
• another condition, such as lung disease or overactive thyroid.

Sometimes atrial flutter can occur without any cause.

Some people with atrial flutter may also have atrial fibrillation and experience periods of atrial flutter followed by periods of atrial fibrillation.

The difference between atrial flutter and atrial fibrillation

Atrial fibrillation is when the upper chambers of the heart (atria) beat irregularly. This causes the atria to twitch (or fibrillate), leading to an abnormal heart rhythm.

Atrial flutter is when the atria beat regularly, but much faster than usual. The top part of the heart beats quicker than the bottom, causing an abnormal heart rhythm.

Diagnosis of atrial flutter

Your doctor should recommend you have an ECG or Holter monitor test to look at the electrical activity of your heart. You may need to have more than one ECG, as sometimes the atrial flutter does not show up.

You many also have an implantable loop recorder fitted under your skin to record the electrical activity of your heart for a longer period. 

Treatment of atrial flutter

Your doctor might recommend treatment with:

• medicines to control your heart rate such as beta blockers, calcium channel blockers and other anti-arrhythmic medicines
• cardioversion
• ablation.

Possible complications

Atrial flutter can change the way blood moves through your heart. This can lead to a blood clot forming in your heart. If the clot breaks off it could lead to a stroke.

To reduce this risk of having a stroke, you may need to take an anticoagulant medicine, such as warfarin or a NOAC.

If left untreated, atrial flutter can also weaken the heart over time and cause heart failure.

It is possible for atrial flutter to go away after treatment, but it may return. If it does return, you will need to follow-up with your doctor and may require further treatment.

Living with atrial flutter

With treatment, you should continue to do everything you enjoy after your diagnosis. However, it can take time to understand what triggers your atrial flutter and you may need to make some changes. 

Living with atrial flutter can also have an emotional impact on you and your family. You may be feeling more anxious or stressed than normal after your diagnosis. If this happens you may wish to speak to your loved ones and your GP for further support.

Heart Helpline and support

• Speak to our cardiac nurses by phone, callback, email or online chat on Heart Helpline (Monday to Friday, 9am to 5pm).
• Sign up to our Heart Matters magazine for online tips, support and recipes to look after your heart health.
• Join our online HealthUnlocked community to speak to other people going through the same experience.