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Learn the signs of atrial fibrillation

Atrial fibrillation (AF) is the most common kind of arrhythmia, or irregular heartbeat. It can lead to serious complications without treatment.

AF doesn't always cause symptoms, but if you have even one of these five common signs, let your doctor know.

1. Fatigue

AF can cause you to feel very tired and out of energy, even after you've slept. You might feel exhausted at any given time or more often during exercise.

2. A racing heartbeat or heart palpitations

Some people say AF feels like their heart is racing, fluttering, pounding, quivering, flopping or skipping beats in their chest. Some people notice these sensations more often when they are physically active.

3. Shortness of breath

AF can cause you to feel short of breath. You might also feel anxious, worried, frightened or nervous when you are out of breath.

4. Dizziness

With AF, you may feel dizzy or weak sometimes.

5. Faintness or confusion

You might feel confused, faint or like you're going to pass out (what doctors call syncope).

AF increases stroke risk

Learn about other stroke risk factors and assess your risk by taking our assessment.

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