What Atrial Flutter Looks Like on Your Watch ECG

QALY Team
Atrial Flutter on smartwatch ECG (Apple Watch, Kardia, Fitbit, Samsung)

Key Takeaways

Atrial flutter is a common disorder that causes the heart to beat in irregular patterns. People with atrial flutter have a heart rhythm that's more organized and less chaotic than atrial fibrillation. Sometimes a person may have episodes of both atrial flutter and atrial fibrillation.

People with atrial flutter may not have symptoms. However, the disorder can increase the risk of stroke, heart failure, and other complications. There are effective treatments for atrial flutter, including medication or procedures designed to scar small areas of heart tissue (ablation).

Atrial flutter is classified as typical or atypical (non-typical) depending on the location of the short circuit. This pathway allows the electrical signal to move too fast around the heart. While the symptoms are similar, the treatments may differ.

  • Typical atrial flutter is localized to the right atrium. This type of atrial flutter can be cured with a short outpatient catheter ablation procedure.
  • Atypical atrial flutter refers to atrial flutter arising in the left atrium. Most types of atypical atrial flutter can also be treated with catheter ablation, but the procedure is longer and more involved.

How to Spot Atrial Flutter on Your Watch ECG

In atrial flutter, electrical impulses don't travel in a straight line from the top of your heart to the bottom. Instead, they move in a circle inside the upper chambers. As a result, your heart beats too fast but still in a steady rhythm.

The following ECG characteristics can help identify atrial flutter:

  • Typical atrial flutter is localized to the right atrium. This type of atrial flutter can be cured with a short outpatient catheter ablation procedure.
  • Rate: The heart rate in atrial flutter is usually fast. It may be normal or slow with drug therapy.
  • P wave: Flutter waves or “F” waves are present in a “sawtooth” appearance.
  • QRS complex: Usually narrow.
  • Rhythm: Regular (can be irregular).

The electrical current or rhythm has a characteristic sawtooth pattern. This atrial activity is called flutter (F) waves. F waves are often seen in a ratio of 2, 3, 4, and even 5 F waves to each QRS complex. This means that the atria (represented by the F waves) are depolarizing and contracting at a rate equal to the ratio of F waves to QRS complexes. When interpreting this rhythm, the ratio of F waves to QRS complexes is usually included; for example, atrial flutter 3:1.  

Example of Atrial Flutter with 2:1 ratio of F waves to QRS complex
Example of Atrial Flutter with 2:1 ratio of F waves to QRS complex

Example of Atrial Flutter with 2:1 ratio of F waves to QRS complex
Example of Atrial Flutter with 3:1 ratio of F waves to QRS complex

Example of Atrial Flutter with 4:1 ratio of F waves to QRS complex

Example of Atrial Flutter with variable ratio of F waves to QRS complex

Common Symptoms, Complications, and Treatment of Atrial Flutter

Atrial flutter is usually an age-related arrhythmia because it rarely occurs before age 50, but becomes more common after.

Symptoms include:

  • Stroke
  • Palpitations (a fluttering in the chest)
  • Dizziness or fainting
  • Shortness of breath
  • Fatigue

Any Cause for Concern?

Atrial flutter does raise your chance of having a stroke. But your outlook is generally quite good if you don’t have another heart disease. You may never have it again if it happens once without severe heart or lung disease. If you have other heart diseases, your atrial flutter may come back. As always, if you show signs of a potential atrial flutter, contact your healthcare provider as soon as possible to rule out the presence of harmful underlying conditions.

Complications of atrial flutter include:

  • Blood clot formation. If a blood clot travels from the heart into the bloodstream, it could become lodged in an artery and cause a stroke.
  • If the heart beats very quickly over a long period, it may lead to cardiomyopathy, weakening the heart muscle.

Sometimes, atrial flutter goes away by itself, and no further action is needed. If it persists, your doctor may pursue any of the following treatments:

  • Catheter ablation: procedure to destroy the errant electrical pathways; performed together with an electrophysiological study.
  • Cardioversion: small, controlled shock to the chest done under anesthesia to provide short-term correction of the heart rhythm.
  • Medications to control the heart rhythm, called antiarrhythmics, may be less effective than catheter ablation.
  • Medications to prevent blood clots.

An irregular heart rhythm can affect how well you can work, exercise, and do other activities. To manage it, follow the treatment plan your doctor prescribes. Medicines and other therapies can help control symptoms, like shortness of breath and palpitations, and lower your odds of having a stroke or heart failure. As always, if you show signs of a potential atrial flutter, contact your healthcare provider as soon as possible to rule out the presence of harmful underlying conditions.


Still Not Sure How to Spot Atrial Flutter on Your Watch ECG?

Your smartwatch can also be your partner in looking after your heart. If you’re concerned about atrial flutter, get your smartwatch ECGs analyzed by experts within minutes on the QALY app: iOS and Android.

Get second opinions of your ECGs on the QALY app!

Get second opinions of your ECGs on the QALY app!

Heart Feels Off? Get Your ECGs Analyzed by Experts on the QALY App.

Interpret My ECG Now

By using this website, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. View our Privacy Policy for more information.