
Key Takeaways
Atrial fibrillation (Afib) is a condition that disrupts your heartbeat. A glitch in the heart’s electrical system makes its upper chambers (the atria) beat so fast that they quiver or fibrillate. This causes the lower chambers (the ventricles) to beat out of sync. Afib, or A-fib, can be dangerous because it raises your risk of stroke and heart failure. Usually, the atria and ventricles work together, so the heart pumps blood in a steady rhythm. But in Afib, they don't. The irregular beats can cause a fast, fluttering heart rate (100-175 beats per minute) instead of the normal (60-100 beats per minute).
Atrial fibrillation used to be classified as either chronic or acute. But in 2014, new guidelines from the American College of Cardiology and American Heart Association changed the classification of atrial fibrillation from two types to four:
- Occasional (paroxysmal atrial fibrillation). Afib symptoms come and go, usually lasting for a few minutes to hours. Sometimes symptoms occur for as long as a week, and episodes can happen repeatedly. Symptoms might go away on their own. Some people with occasional Afib need treatment.
- Persistent. With this type of atrial fibrillation, the heart rhythm doesn't go back to normal on its own. If a person has Afib symptoms, cardioversion or treatment with medications may be used to restore and maintain a normal heart rhythm.
- Long-standing persistent. This type of atrial fibrillation is continuous and lasts longer than 12 months.
- Permanent. The irregular heart rhythm can't be restored in this type of atrial fibrillation. Medications are needed to control the heart rate and prevent blood clots.
How to Spot Atrial Fibrillation on Your Watch ECG
The following ECG characteristics can identify Atrial Fibrillation:
- Irregularly irregular rhythm.
- No distinct P-waves and replaced with “fibrillatory waves” or “f” waves.
- Narrow QRS complexes.
Smartwatches like Apple Watch, Samsung, and Fitbit Sense can pick up these readings. You can have these interpreted by a medical professional for more information that can help guide treatment and help you better monitor your condition.
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Common Symptoms of Atrial Fibrillation
The basic cause of Afib is disorganized signals that make your heart's two upper chambers (the atria) squeeze very fast and out of sync. They contract so quickly that the heart walls quiver or fibrillate. Some people with atrial fibrillation have no symptoms and are completely unaware that their heart rate is irregular. The following are the common symptoms:
- Sensations of a fast, fluttering, or pounding heartbeat (palpitations)
- Chest pain
- Dizziness
- Fatigue
- Lightheadedness
- Reduced ability to exercise
- Shortness of breath
- Weakness
Any Cause for Concern?
Afib is a serious diagnosis. While this condition isn't fatal in itself, it can lead to potentially life-threatening complications. Two of the most common complications of Afib are stroke and heart failure, both of which can be fatal if not managed quickly and effectively. As always, if you show signs of a potential Afib, contact your healthcare provider as soon as possible to rule out the presence of harmful underlying conditions.
Still Not Sure How to Spot Atrial Fibrillation (Afib) on Your Watch ECG?
Your smartwatch can also be your partner in looking after your heart. If you’re concerned about atrial fibrillation, get your smartwatch ECGs analyzed by experts within minutes on the QALY app: iOS and Android.
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